FACULTY OF MEDICINE INSTITUTE OF BIOLOGY SYSTEMS AND GENETIC RESEARCH HELENE TONNER

Transcription

1 FACULTY OF MEDICINE INSTITUTE OF BIOLOGY SYSTEMS AND GENETIC RESEARCH HELENE TONNER THE MOST LIKELY INFECTION PATHWAYS OF TOXOCARA SPP. AND COMPARISON OF INFECTION RISK AMONG STUDENTS OF THE LITHUANIAN UNIVERSITY OF HEALTH SCIENCES PROGRAMME OF INTEGRATED STUDIES MEDICINE ASSOC. PROF. DR. LINA MICKIENĖ KAUNAS 2015/16 1

2 TABLE OF CONTENTS 1. TITLE PAGE ERROR! BOOKMARK NOT DEFINED. 2. TABLE OF CONTENTS 2 3. SUMMARY(IN LITHUANIAN AND IN ENGLISH) 3 4. ACKNOLEDGEMENTS 4 5. CONFLICTS OF INTEREST 4 6. CLEARANCE ISSUED BY THE ETHICS COMMITTEE 4 7. ABBREVIATIONS (IF APPLICABLE) SEPARATE PAGE 5 8. TERMS 6 9. INTRODUCTION AIM AND OBJECTIVES LITERATURE REVIEW PREVALENCE THE LIFECYCLE OF TOXOCARA SPP CLINICAL MANIFESTATION AND TYPES OF TOXOCARIASIS Visceral larva migrans (VLM) Ocular larva migrans (OLM) Neurotoxocariasis (NT) Covert or common toxocariasis (CT) DIAGNOSIS OF TOXOCARA SPP TRANSMISSION OF TOXOCARA SPP. TO HUMANS AND RISK OF INFECTION CONTROL STRATEGIES/ PREVENTION RESEARCH METHODOLOGY AND METHODS RESULTS, DISCUSSION OF THE RESULTS IDENTIFICATION OF PET OWNERS IN THE TWO GROUPS OF STUDENTS THE COMPARISON, BETWEEN THE TWO GROUPS, OF THE RISK OF THE ACCIDENTAL INGESTION OF EGGS PROPHYLACTIC MEASURES TAKEN TO REDUCE THE AMOUNT OF EGGS DISPERSED IN THE ENVIRONMENT, BY MEANS OF PICKING UP ANIMAL FAECES AND BY ADMINISTERING ANTIHELMINTHS COMPARISON OF THE HAND WASHING ROUTINE IN BOTH GROUPS THE CORRELATION BETWEEN SELF- INDICATED KNOWLEDGE OF POSSIBLE INFECTION PATHWAYS OF TOXOCARA SPP. AND THE RESULTS OF THEIR ACTUAL KNOWLEDGE CONCLUSIONS REFERENCES ANNEXES 29 2

3 3. SUMMARY(in Lithuanian and in English) Helene Tonner THE MOST LIKELY INFECTION PATHWAYS OF TOXOCARA SPP. AND COMPARISON OF INFECTION RISK AMONG STUDENTS OF LSMU Research aim: Comparing different student s populations with each other, in this case medical students with students of other study programmes of LSMU, I want to find out if there is a difference between those groups of students. I have been looking for student s attitudes towards pet ownership, how pets are kept at home,which habits and actions influence the reduction of the egg load in the environment and how well hygienic measures are used by pet owners as well by those students without any pets. The use of a questionnaire is the main tool to get an answer to these questions. Unfortunately it was not possible for me to investigate the seroprevalence in my observed sample of students, which would have made a substantial finding that could have been compared to other people s epidemiological research. Objectives: 1. to determine among observed students the amount of pet owners, specifically identifying dog and cat owners. 2. to find out if there is a difference, between the two observed groups of students, in the risk of accidentally ingesting the eggs of the parasite. 3. to compare the two observed student groups by indicating how well prophylactic measures are used to reduce the amount of Toxocara spp. eggs in the environment. 4. to analyze the difference of hand washing routine in both groups of students. 5. to test if the self estimation about the knowledge of possible toxocariasis infection pathways correlates to the actual knowledge of the students. Methods: A unique questionnaire was developed and handed out to students of LSMU including tailored questions, about their personal hygiene, measures of sanitation regarding animals as well as their attitudes towards pet ownership in their daily life. Study participants: The questionnaire was handed out to a total sample of 448 students. The sample was divided into two groups, group I (G1) with 232 medical students, and group II (G2) with 216 students including odontology faculty (48 students), pharmacy faculty (19 students), veterinary faculty (8 students), students of oral hygiene (23 students), food safety (12 students), medical veterinary genetics (74 students), animal science (11 students) and public health (21 students). The reason why these two groups are divided in this manner is to have to comparable groups of similar sample sizes. Research results: In G1 43% and in G2 53% keep a dog. In both groups 42% keep a cat. In G1 30% of the dogs were allowed to move freely inside the house, in G2 only 13%. G1 lets their cats move inside and outside with 40%, G2 with 16%. 56% of G1 let their animal touch personal belongings, in G2 3

4 38%. 58% in G1 and 67% in G2, let their animals sleep in their bed. Among all students, 7% in G1 and 13% in G2 admitted not always to wash fruit and vegetables after purchase. 50% in G1 and 45% in G2 claimed that they collect their pets faeces. G1 uses antihelminths according to reccomendations with 23% compared to G2 with 21%. Students wash hands before preparing a meal or eating 71% in G1 and 76% in G2, after working in the garden 61% in G1 and 71% in G2, 64% in G1 and 66% in G2 when they are dirty. Only 0,23% of all students answered the question about infection pathways corectly. Conclusions: The majority of all students keep a pet. More than half of the students in each study programme separately keep a pet, except for odontology students. All pet owners are most likely to be infected by eggs spread to bed sheets. The highest risk factor is that pet owners let their pets rummage trough personal belongings, the next is that the pets can spread dirt and hair within the house because they are allowed to move freely inside it. The least potential infection pathway is by ingesting infected fruit or vegetables. G1 is better at actively reducing the amount of eggs in the environment. The results also show that G2 uses prophylactic measures better, such as washing their hands after certain actions with a higher risk of transmission.the knowledege of infection pathways is very poor because only one person could answer the question about them correctly. 4. ACKNOLEDGEMENTS I am very grateful to Prof. Dr. L. MICKIENĖ, who has been of great importance for the conduction of this research. I also want to thank Jan Steck and Margarete Tonner for their great support and for always being there when I needed them. 5. CONFLICTS OF INTEREST The author reports no conflict of interest. 6. CLEARANCE ISSUED BY THE ETHICS COMMITTEE All permissions from the head of departments will be added after the Annexes, including the Faculty of Pharmacy, Medical Faculty, Veterinary faculty, Nursing faculty, Faculty of Odontology. 4

5 7. ABBREVIATIONS (if applicable) separate page CT- CT- Common toxocariasis Computed Tomography DNA- ELISA- Deoxyribonucleic acid Enzyme-linked immunosorbent assay ESCCAP- European Scientific Counsel Companion Animal Parasites G1- Group I G2- Group II LSMU- Lietuvos Sveikatos Mokslų Universitetas (Lithuanian University of Health Sciences) MRI- NT- OLM- PCR- T.canis- T.cati- TES- VLM- Magnetic Resonance Imaging Neurotoxocariasis Ocular larvae migrans Polymerase Chain Reaction Toxocara canis Toxocara cati Toxocara spp. Excretory-Secretory Antigen Visceral larvae migrans 5

6 8. TERMS Aberrant - straying from the right or normal way Antihelminths - drugs expelling or destroying parasitic worms especially of the intestine Definite host - the host in which the sexual reproduction of a parasite takes place Embryonate - to produce or differentiate into an embryo Host - a living animal or plant on or in which a parasite lives Prophylaxis - measures designed to preserve health and prevent the spread of disease Zoonosis - a disease communicable from animals to humans under natural conditions 9. INTRODUCTION Toxocariasis in humans is a disease caused by Toxocara spp., which mainly develops after the ingestion of embryonated eggs of the parasite. Toxocara spp. in colloquial language is called roundworm. Toxocara spp. is the most common zoonotic agent in urban public sites and in rural settlements. [1] Humans said to be an accidental host as Toxocara spp. cannot complete their life cycle after infecting humans. Embryonated eggs are found in contaminated soil, on unwashed hands, raw vegetables and fruit or directly on pets [2]. The contamination of the soil or vegetables occurs by the faeces of the infected definite host, such as dogs, foxes, Toxocara canis (T. canis), and cats, Toxocara cati (T. cati). Embryonation occurs after about four weeks after eggs of the parasite have been released into the environment. If has not occurred, the eggs are absolutely harmless. But rarely the parasite might be transmitted after ingestion of larvae found in organs or muscle tissue in undercooked meat of other aberant hosts such as swine or rabbits. After the ingestion of embryonated eggs, the larvae of the parasite move to various organs causing different types of toxocariasis. These types are visceral larva migrans (VLM), ocular larva migrans (OLM), neurotoxocariasis (NT) and covert or common toxocariasis (CT). But this field of zoonotic infection has still not been widely researched and not a lot of recent data exists from case studies or epidemiological research of toxocariasis as well as I could not find any study that relates only to the behaviour towards pet ownership or general behaviour regarding the prophylaxis of toxocariasis. In my opinion it is important to identify risks, prophylaxis and the knowledege about Toxocara spp. as it indicates the lack of information about this disease. 6

7 A questionaire was therefore exclusively designed, in which unique questions were posed, asking about the details in the student s every day life activities and tradititons at home. It includes specific questions relating to the aim of this thesis and covers the estimation of the risk of accidental egg ingestion, by evaluating where pets are kept paying close attention to those that are allowed to move freely inside the home and those that are allowed to touch personal belongings or sleep in one s bed as well as to find out the amount of people that do not wash fruit or vegetables before eating them. The next step includes the identification of students that actively reduce the amount of eggs in the environment, by picking up animal faeces. The questions about the administration of antihelminths to pets were designed to find out if the studetns follow the recommendations made by the European Scientific Counsel Companion Animal Parasites. This is important as it acts as prophylaxis for animals to become a host of Toxocara spp. posing a hazard to fellow animals or humans. Students were asked about their hand washing routine as hand washing serves as the main part of prevention. And finally the students were tested in their knoweldege of transmission,where the results should reflect how much patient education is actually needed for this zoonotic infection. In my research my goal is to find out what the main potential infection pathways in the students of LSMU are, how much knowledge about Toxocara spp. they have and how well the measures of prophylaxis of this infection are taken comparing medical students and other students of LSMU. 10. AIM AND OBJECTIVES The aim is to identify most likely infection pathways of toxocariasis in students of Lietuvos sveikatos mokslų universitetas (LSMU), how high the risk is to be infected, as well as the degree of the student s knowledge of the transmission of Toxocara spp.. Comparing different student s populations with each other, in this case medical students with students of other study programmes of LSMU, I want to find out if there is a difference between those groups of students. The reason why I divided the students into these two groups is to have similar sample sizes, which make it easier for comparison. I have been looking for student s attitudes towards pet ownership, how pets are kept at home, which habits and actions influence the reduction of the egg load in the environment and how well hygienic measures are used by pet owners as well by those students without any pets. The use of a questionnaire is the main tool to get an answer to these questions. Unfortunately it was not possible for me to investigate the seroprevalence in my observed sample of students, which would have made a substantial finding that could have been compared to other people s epidemiological research. 7

8 The objectives in this research are: 1. to determine among observed students the amount of pet owners, specifically identifying dog and cat owners. 2. to find out if there is a difference, between the two observed groups of students, in the risk of accidentally ingesting the eggs of the parasite. 3. to compare the two observed student groups by indicating how well prophylactic measures are used to reduce the amount of Toxocara spp. eggs in the environment. 4. to analyze the difference of hand washing routine in both groups of students. 5. to test if the self estimation about the knowledge of possible toxocariasis infection pathways correlates to the actual knowledge of the students. 11. LITERATURE REVIEW By writing this literature review I want to show the main aspects of toxocariasis. The general understanding of its prevalence, the life cycle of Toxocara spp., clinical manifestations, diagnosis, transmission and control strategies is of great importance to my research. The prevalence shows how apparent the disease is, together with the clinical manifestations it becomes clear why patient education is of such great importance as symptoms are serious but simultaneously very unspecific Prevalence of Toxocara spp. The prevalence throughout the world of the Toxocara spp. plays an important role for the tactics of prevention of infection of the definite hosts such as dogs, cats and foxes, which are the main source for accidental transmission to humans. Pups generally have higher infection rates than adult animals and are a major source of Toxocara spp. s eggs in the environment.[2] Reported infection rates of T. canis and T. cati in Western Europe vary from % for T. canis for dogs in different epidemiological environments and from 8-76% in T. cati in cats.[2] Consequently the risk to humans acquiring Toxocara spp. from infected animals is quite high. A recent study investigated the prevalence of helminths in dogs in Mampong, Ashanti, Ghana. The excrements of 154 dogs were collected and 18.8% were positive for T. canis, leading to the conclusion that dogs play an active role in the transmission of Toxocara spp..[3] Many studies dealt with the detection of seropositive humans for Toxocara spp. on a worldwide scale. Seropositivity in humans is the main tool for the diagnosis of Toxocariasis. Comparisons were made 8

9 between high industrial and developing countries. It is indicated that the seropositivity of T. canis is much less in industrialised countries compared to developing countries. An example is the prevalence of 2,4% in Denmark in comparison to the prevalence of 93% on Reunion Island.[4] In this study other developing countries prevalence ranged from 30-81%, which indicated that the infection of T.canis has a severe impact on worldwide human health, which nowadays still has not been recognized. Another example is from a study made in Poland, where random children were tested for toxocariasis. None of the children had any symptoms but the overall seroprevalence in these children was 4.2 % as determined by ELISA.[5] Even though they did not present with any symptoms the question still remains what does it mean to be infected with Toxocara spp. and what ist he impact oft he children s future health The lifecycle of Toxocara spp. The genus Toxocara spp. belongs to class Nematoda, order Ascaroidea, and Superfamily Ascaridoidea and comprises 21 species. To understand the importance of risk factors and prevention one must know how humans can be potentially infected. Therefore it is of great importance to know about the life cycle of Toxocara spp. The life cycle is best explained by the use of a diagram (Fig.1). Fig. 1. Life cycle of Toxocara spp. 9

10 The numbers after the sentences indicate the step of the life cycle of Toxocara spp. in Fig.1. The definite hosts of Toxocara spp. are dogs and cats. In case they are infected by these roundworms, the eggs of the parasite are passed in the faeces (1) and can be found in the environment. Once released into the environment, eggs are not immediately infectious. (6) The eggs embryonate in about five weeks (2), depending on the humidity and temperature of the soil. During this period, the eggs can be dispersed by other animals throughout the environment by other animals and can be later found in children s sandboxes, in the soil of public parks, on fruit and vegetables. The definite host (3), an intermediate host (7) or humans (9) can then accidentally ingest the infested soil or vegetables. Therefore humans, as accidental host, can be either directly infected by the ingestion of eggs or by the ingestion of larvae of the parasite found in meat (10). After the ingestion of embryonated eggs, the larvae of Toxocara spp. are released and can move to various organs (11) either of the intermediate or accidental host. Dogs or cats can be re-infected by eating infected animals, such as mice, rats and birds, in which larvae are present in various organs (8). Larvae of the roundworm develop into egglaying adult worms only in the small intestine of their definite host (4) and release eggs, which are then excreted in the faeces (1). In the case of T.canis trans-placental transmission can occur if the encysted state of the parasite becomes active in late pregnancy (5). In pups the adult worm develops in the intestine and eggs are passed in faeces (1) Clinical manifestation and types of toxocariasis The clinical manifestation of toxocariasis in humans varies due to many different factors such as the organs affected and the immune status of the host. Generally toxocariasis is a non-fatal disease in humans. According to the organs, in which the disease has spread, toxocariasis is divided into several types. Currently, human toxocariasis is clinically classified into four major types [3], which are visceral larva migrans (VLM), ocular larva migrans (OLM), neurotoxocariasis (NT) and covert or common toxocariasis (CT).[7] Some sources suggest that the amount of eggs ingested and genetic predisposition as well as the general immunity status of the host plays a vital role in the severity and which form of toxocariasis will develop Visceral larva migrans (VLM) This is the most common form of toxocariasis in humans and is mostly observed in preschool aged children between the ages 1-7 years old but also common in adults.[2] Symptoms are mainly general and unspecific, which makes the diagnosis very difficult. In most cases toxocariasis is not serious and many people, especially adults, may not notice any symptoms. But in case when the infection is more serious, potential symptoms and other clinical 10

11 findings include fever, hepatomegaly, abdominal pain, vomiting, diarrhoea, coughing/wheezing, asthma, inappetence, weight loss, fatigue and headache.[2] Children can present with severe infection and can suffer from seizures, myocarditis, and encephalitis. The immediate hypersensitivity response to the death of larvae is thought to be the main cause for symptoms of VLM. [7] The hypersensitivity response shows up as persistent leucocytosis in patients, mainly eosinophils are predominant in these cases but also specific immunoglobulins can be seen in blood samples Ocular larva migrans (OLM) After infection with Toxocara spp. the parasitic larvae can invade the retina, typically in pre- school children, which have a high-risk behaviour such as geophagia, dog ownership, poor personal hygiene or ingestion of raw or undercooked meats of an intermediate host. The findings of a recent study shows what the migration of the parasitic larva can cause in the eye, consequences can be peripheral granulomas, vasculitis, vitreoretinal tractions and chronic macular edema.[8] The formation of granulomas, from the invasion to the retina lead to several different symptoms such as visual impairment or by dragging the retina creating distortions, heterotopia or detachment of the macula leading to blindness. OLM can also cause infections of the internal layers of the eye or of the papilla. Again an eosinophilic immune response takes place, which leads to granuloma formation in the eye. Bilateral ocular involvement has been described but can be considered uncommon.(9) Neurotoxocariasis (NT) The number of reported cases of neurotoxocariasis is very small and varies between 29 and 50 cases [10] listed in literature reviews of case reports from the early 1950s until today. Therefore this type of toxocariasis is not very common or completely underdiagnosed due to its pretty unspecific signs and symptoms. A study revealed that he predominant clinical pictures were mostly myelitis then encephalitis and meningitis, fever was only present in one fourth of the patients infected with Toxocara spp.[11]. It has been reported that patients suffered from motor impairment such as ataxia, rigor, para- or tetraparesis and dysaesthesia as well as urinary retention and faecal incontinence Covert or common toxocariasis (CT) Covert toxocariasis is another form of toxocariasis that has been described in literature. Patients are diagnosed if they are seropositive and have symptoms, which will be listed below, that have no other possible cause and cannot be classified into OLM, VLM or NT. 11

12 Covert toxocariasis was characterized clinically in children by fever, anorexia, headache, abdominal pain, nausea, vomiting, lethargy, sleep and behavioural disorders, pharyngitis, pneumonia, cough, wheezing, limb pains, cervical lymphadenitis and hepatomegaly. Common toxocariasis in adults was characterized clinically by weakness, pruritus, rash, difficult breathing, and abdominal pain.[9] 11.4 Diagnosis of Toxocara spp. There are different approaches for the diagnosis of toxocariasis. Diagnostic tools include immunodiagnostic or molecular techniques, biopsies of the affected tissues, detection of the DNA of Toxocara spp. and various medical imaging techniques. The most commonly used diagnostic methods are serological techniques such as the enzyme-linked immunosorbent assay (ELISA) with Toxocara spp. excretory-secretory (TES) antigen or Western blotting. The Western blotting technique compared to ELISA gives a better specificity, with reactivity to bands of low molecular weight proven to be specific for T.canis infection. ELISA is in that way less specific because of its antigenic crossreactivity in polyparasitism. Especially in developing countries polyparasitism is not very uncommon and therefore ELISA is not specific in enough in those cases. Downsides of the Western blotting technique are that it is more expensive and more labour intensive. However, it is also possible to detect Toxocara spp. Deoxyribonucleic acid (DNA) from tissues in suspected clinical toxocariasis by polymerase chain reaction (PCR). The examination of a biopsy of the affected tissue, additionally using special staining techniques, can provide a definitive diagnosis but such biopsies are rarely available. Furthermore Toxocara spp. larvae can be detected using various medical imaging techniques, such as ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). For the examination of biopsies and evaluation from the different imaging modalities, the examiner needs to be skilled enough to recognize the infection signs made by the Toxocara spp.. This is often not the case because there are such few cases recognized in literature. Exclusively for VLM, blood counts always show the presence of a high grade eosinophilia. [12] In the common clinical practice toxocariasis is diagnosed using the serological results. It has been proposed that a seropositivity alone is of little clinical significance, only the combination of seropositivity and blood eosinophilia is indicative of active toxocariasis. In general, only patients with clinical signs of a toxocariasis are eligible for therapy Transmission of Toxocara spp. to humans and risk of infection The transmission of Toxocara spp. to humans is accidental; this makes humans aberrant hosts. They 12

13 are unfit for Toxocara spp. to complete its life cycle. The oral-faecal transmission cycle plays the main role in this disease and humans can be infected by ingestion of larvae in under-cooked infected organ or muscle tissues, infective eggs from contaminated soil (gardens, sandpits and play-grounds), from unwashed hands or raw vegetables or by direct contact with pets.[13] Children are particularly prone to infection with Toxocara spp. because they are exposed to the eggs in sandboxes in playgrounds, contaminated with dog and cat faeces. [14] In a study in Iran, 386 fresh raw vegetables were checked for parasitic egg infestation. Toxocara spp. was found on 1.68% of them, meaning that there is an actual risk of aquring toxocariasis by ingesting unwashed fruit and vegetables.[15] Especially in children the risk of being infected with Toxocara spp. is extremely high because of their risky behaviour such as geophagia, playing in public sandboxes, poor personal hygiene and general tendency to put things in their mouth, especially in pre-school children. A study showed that there is no difference in the zoonotic risk of infection between T.canis and T.cati [16]. These days more and more people keep cats and dogs as pets worldwide therefore it has become the main cause of human toxocariasis. [17] 11.6 Control strategies/ Prevention The two main control strategies are to prevent toxocariasis in humans by reducing the output of eggs from animal faeces into the environment and to prevent the infection by already dispersed eggs in the environment. Prophylactic measures must be taken in both cases. The main action to decrease the new output of eggs into the environment is to eliminate the infection in cats and dogs. Antihelminths are given to pets on a regular recommended basis. Recommendations exist from the ESCCAP in Europe. Annual or bi-annual treatments have no significant impact on preventing patent infection within a population.[18] The general recommendation is to give antihelmints every three months. In pets with a higher risk of acquiring and spreading the disease such as free- roaming animals with the contact to other animals, the antihelmintic therapy should be given at shorter intervals. A number of countries have implemented reproductive control programs in owned and stray dogs to reduce the number of young dogs in the population. These programs would positively impact upon T. canis transmission since the parasite is most fecund and prevalent in puppies.[19] 13

14 Not only the usage of such drugs in animals but also the prevention of defecation for pets in public places, especially playgrounds and other public recreation areas are an important approach to control the disease. Personal hygiene, such as hand washing, is one of the main steps in prevention of the disease because its transmission occurs by the faecal-oral route. Maybe the most important aspect of prevention is education of the public about Toxocara spp. s life cycle and routes of transmission. Veterinarians should encourage pet owners to immediately dispose of dog s and cat s faeces as well as they should advice pet owners to have their pets checked for parasitic infections and dewormed on a regular basis. [20] 12. RESEARCH METHODOLOGY AND METHODS A questionnaire was developed and handed out to students of LSMU including questions about their personal hygiene, measures of sanitation regarding animals as well as their attitudes towards pet ownership. The questionnaire covers questions to assess risk factors of pet owners and those without pets as well as questions about measures of prophylaxis regarding the transmission of Toxocara spp. These risk factors have been previously been described in literature. The questionnaire was handed out to a total sample of 448 students, including students of the medical faculty (232 students), odontology faculty (48 students), pharmacy faculty (19 students), veterinary faculty (8 students), students of oral hygiene (23 students), food safety (12 students), medical veterinary genetics (74 students), animal science (11 students) and public health (21 students). I The sample was then divided into two groups, G1 (medical faculty group) with a total number of 232 students and G2 (other group), consisting of 216 students, including all other mentioned courses, to have a similar number of participants in each group to make them comparable. The questionnaires were collected and the relevant data was encoded and assembled in a table using Microsoft Excel Version During the assessment it turned out that a part of the questions were not target- aimed, hence only specific ones were filtered out to answer to the aim and objectives of this thesis. 13. RESULTS, DISCUSSION OF THE RESULTS The two groups have about the same sample size, G1 with 232 students and G2 with 216 students. The average age of all students as well as in each group seperately is 20 years old. The similar sample size and the same average age make the two groups easily comparable. 14

15 13.1 Identification of pet owners in the two groups of students The majority of all students keep a pet, 66% keep a dog, a cat or both (Fig.2). Since the most likely infection pathways of Toxocara spp. is through dogs and cats it was important to identify the amount of students that keep dogs, cats or both. Interesting to see that in G2 more than half of the students, 53%, keep a dog and in G1 a total of 43%. In both groups an equal amount of 42% keep a cat. This huge number supports the statement that more and more people in urban areas keep pets and that the degree of exposure to zoonotic infections is becoming higher. The similar number of dog and cat owners make it easier to compare both groups with each other. In total 68% of G1 and 75% keep a dog, a cat or both. Taking all students into account that were given this unique questionaire, we observe that there are more students owing a pet compared to those not having one. My sample size is composed of 448 students from different programme studies,which are medicine (232 students), odontology faculty (48 students), pharmacy faculty (19 students), veterinary faculty (8 students), students of oral hygiene (23 students), food safety (12 students), medical veterinary genetics (74 students), animal science (11 students) and public health (21 students). More than half of the students of all study programmes, except odontology students, are a pet owner. In the programme of animal science all the students, that were given the questionnaire, own a pet (Fig.3). 5% 18% 24% 24% 29% No pet Cat and Dog Dog Cat Other Fig.2 Identification of pet owners in all students 15

16 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% % Students without pets % Pet owners Fig.3 Identification of pet owners within each study programme (%) 13.2 The comparison between the two observed groups of the risk of the accidental ingestion of eggs Accidental ingestion is increased by owning a pet and the way how it is handled. By examining the way pets are kept using only the number of participants that own a pet and by looking at all participants what routine they have for washing fruit and vegetables The questionaire that was handed out asked the participants specifically about the way they keep their dog or cat. To identify the increased risk for the transmission of Toxocara spp., the particiants were asked several questions about situations in which a dog or a cat can spread the eggs. Hereby I divided the pet owners from the ones without a pet. The first question was about where their pet is kept. If the dog is freely moving inside of the house it can scatter dirt or hair containing eggs througout all areas and therfore present a higher risk for the human to accidentally ingest dirt or hair. In G1 30% of the dogs were allowed to move freely inside the house whereas in G2 only 13% were allowed to do so (Fig.4). Therefore the risk to scatter dirt or hair inside the house is higher in G1, which means that the risk of accidentaly ingesting eggs is higher in G1. 16

17 35.00% 30.00% 25.00% 20.00% 15.00% 10.00% 5.00% 0.00% 1 2 Fig.4 Amount of dogs (%) that are allowed to move freely inside the house in G1 and G The highest probability for cats to transfer the eggs inside the house is, if they have no fixed area where they can stay and are allowed to move inside and outside of the house. In this case G1 lets their cats move inside as well as outside with 40%, G2 with 16% (Fig.5). The risk of Toxocara cati (T.cati) eggs to be dispersed throughout the house as well as the spreading of the eggs outside of the house is much higher in G1. If the cats are allowed to go outside and are able to defecate in gardens and sandboxes they are a potential source of the parasite and can spread it to other animals or directly to humans. It increases the risk of reinfection by increasing the egg load in the environment % 40.00% 35.00% 30.00% 25.00% 20.00% 15.00% 10.00% 5.00% 0.00% 1 2 Fig. 5 Amount of cats (%) allowed to move freely inside the house and outside in G1 and G A higher risk of accidental ingestion of eggs exists if pets are allowed to directly touch personal belongings. 56% of G1 let their animal rummage through personal belongings, in G2 38% (Fig.5). Therefore group I has a higher change of acidentally ingesting the eggs by toughing personal belongings that have been touched by their pets More than half in both groups let their animals sleep in their bed, 58% in G1 and 67% in G2 let their pet sleep in their bed (Fig.6). By being allowed to sleep on the bed, pets can unintentionally soil 17

18 the bedding and dispers the eggs. G2 has a higher possibility to involuntarily be infected with the parsite s eggs % 70.00% 60.00% 50.00% 40.00% 30.00% 20.00% 10.00% 0.00% pets allowed to rummage through personal belongings pets allowed to sleep on the bed G1 G2 Fig.6 Amount of pets (%) being allowed close contact with personal belongings and bed sheets Another way of transmission of Toxocara spp. eggs is by ingestion of unwashed fruit or vegetables. Taking the whole sample with pet owners and non pet owners, 7% in G1 and 13% in G2 admitted not always to wash them after purchase or after they were freshly picked. Therefore in G2 the probability of getting infected with Toxocara spp., by this way of transmission, is higher but much less than being infected by eggs being spread to personal belonging or beds. Comparing pet owners to those who do not have a pet the difference in washing fruit and berries is 9%, pet owners being more thorough in doing so (Fig.7). 100% 98% 96% 94% 92% 90% 88% 86% 84% non pet owners pet owners Fig.7 Amount of students (%) washing fruit and berries before eating them 18

19 13.3 Prophylactic measures taken to reduce the amount of eggs dispersed in the environment, by means of picking up animal faeces and by administering antihelminths The questions regarding prophylactic measures were aimed at dog and cat owners only An important aspect in the transmission of Toxocara spp. is the risk of the dog or cat to become a host. A main way of preventing the spreading of the disease is to pick up animal faeces as they might be potentially infected if no other means of prophylaxis are undertaken against the helminth infection. Only 50% in G1 and 45% in G2 claimed that they collect their pets faeces and put them into a designated bin. Most cat owners let their cats go outside of the house, G1 51% and G2 60% in these cases cat faeces are not picked up and present a potential hazard for other animals and humans to become infected (Fig.8). If faeces are left in the environment the eggs can embryonate and are found in sandboxes, soil and vegeatbles or fruit. By ingestion, the cycle of Toxocara spp. begins again by infection of the definite host or infection can occur of the accidental hosts, in which the larval stage occurs % of pet owners do pick up their pet s faeces every time they defecate outside. The high percentage of pet owners not picking up the faeces is truly worrying. In conclusion I can say that G2 is less careful in preventing the spreading of the parasite. 62% 60% 58% 56% 54% 52% 50% 48% 46% 44% dog faeces cat faeces G1 G2 Fig. 8 Cat and dog faeces not being picked up by pet owners (%) Another way of preventing the spreading of the disease, other than picking up faeces, is to regularly administer antihelmintics to pets. There are specific guidelines made by ESCCAP, which decribe in which intervals antihelminths should be given. The general recommendation to prevent infection is to give antihelminths at least every three months to adult dogs or cats. The participants, which have a dog or a cat, were asked if they are giving their pets antihelmintics and if yes how often the do so. In G1 61% and in G2 70 % give their pets these tablets. In G1, 9% give them less than once a year, 19

20 31% once a year, 36% more than once but less than 4 times a year and 23% every three months. In G2, 13% less than once a year, 23% once a year, 40% more than once a year but less than four times and 21% every three months. In literature it is described that giving these tablets to pets less than every three months does not help in the reduction of the amount of eggs present in the environment. To compare the two groups only the number of students that follow recommendations of the ESCCAP help in the prevention of the disease. Consequently I can say that in both groups this type of prophylaxis is used in a very similar way. Only about one fith in both groups follow the European recommendations, G1 uses this type of prophylaxis slightly better with 23% compared to G2 with 21% (Fig.9) % 40.00% 35.00% 30.00% 25.00% 20.00% 15.00% Group I Group II 10.00% 5.00% 0.00% <1 x year 1x year 2-3 x year 4x year Fig. 9 Antihelminths administration in dog and cat owners (%) 13.4 Comparison of the hand washing habits in observed students One of the most important question in my questionnaire was, if and when the students are washing their hands. Especially it is interesting to know how many people wash their hands before preparing food, before a meal and after working in the garden because the chances of aquiring Toxocara spp. eggs and accidentally ingesting it is the highest. Taking into account all participating students, 58% in G1 and 67% in G2 wash their hands in those cases. These actions are divided to compare the results between the two groups. Before preparing a meal or eating 71% in G1 and 76% in G2 wash their hands. After working in the garden 61% of all students in G1 and 71% of G2 wash their hands. 64% in G1 and 66% in G2 wash their hands only when they are visibly dirty. 20

21 In all these situations the percentage of people washing their hands is higher in G2 than in G1. Meaning that G1 has a higher chance of accidentally ingesting embryonated eggs, regardless of pet ownership (Fig.10). 80% 70% 60% 50% 40% 30% 20% 10% 0% Handwashing rountine before and after a meal working in the garden when tey are visibly dirty G1 G2 Fig.10 Handwashing routine in G1 and G2 (%) Identifying cat owners only, the question about washing hands after cleaning the cat s litter tray and after playing with your pet was asked. In this case 53% and 58% of the students do not wash their hands, respectively. Only taking dog owners 64% do not wash their hands after playing with their pet at home and 58% do not wash their hands after taking it outside for a walk. (Fig.11) This is an extremely large percentage, by not washing your hands after these activities the chances of unintentionally ingesting eggs, that could have been stuck in fur, in soil on the fur or after picking up the faeces during the walk, is much greater. 70% 60% 50% 40% 30% 20% 10% 0% do not wash hands after cleaning litter box/ walking the dog outside do not wash hands after playing with the pet cat owners dog owners Fig.11 Dog and cat owners behaviour after possible contact with pet faeces and hair (%) 21

22 Looking at the handwashing routines of all students, comparing those with a cat, dog or both and those without any pet, we can see a trend that cat owners are least careful in washing their hands in the following situations: handwashing after using the bathroom, before and after a meal, after working in the garden and when they are visibly dirty (Fig.12) % 90.00% 80.00% 70.00% 60.00% 50.00% 40.00% 30.00% 20.00% no pet cat and dog dog cat 10.00% 0.00% after using the bathroom before and after a meal working in the garden when they are dirty other Fig.12 Hand washing habits of observed students without pets and those with a cat, dog or both (%) 13.5 The correlation between self-indicated knowledge of possible infection pathways of Toxocara spp. and the results of their actual knowledge Another part of the questionaire was related to find out the students knowledge of toxocariasis. The answers to the question, if the term toxocariasis is known to the students is of special interest because there is a huge difference between the two groups, 88% of G1 said that they know it and only 31% in G2 (Fig.13). The same tendency is seen in the next question, in which 80% of the sudents in G1 claimed hat they know how one can get infected, in G2 it was only 23% (Fig.14) 100% 100% 80% 80% 60% 60% 40% 40% 20% 20% 0% G1 G2 0% G1 G2 Fig.13 Amount of students that have heard of the term "Toxocariasis" (%) pathways (%) Fig. 14 Self-indicated knowledge of observed students about infection 22

23 The next question was to test their selfestimation by posing the question about possible pathways for infection with Toxocara spp. parasites. Seven options were given of which only three answers were correct. The correct answers were washing fruit or vegetables, washing hands after working in the garden or playing in a sandbox and eating meat that has not been sufficiently thermally treated. The incorrect answers were, eating unwashed candy, cookies and cakes, not washing your hands after petting a diseased stray dog or cat, petting pet birds, such as canaries or parrots and not washing your hands before a meal after working with a computer or speaking on the phone. Only one person in G1 has answered this question corectly, chosing only those three options. That makes only 0,23% of all students who have been asked. The results of the other correcly answered questions, when each correct answer is taken separately from the other posible answers are as follows. Transmission occurs after eating unwashed vegetables or fruit, 22% in G1 and 23% in G2. Not washing hands after working in the garden or before a meal, G1 58% in G1 and 41% in G2. Eating undercooked meat, 9% in G1 and 21% in G2. Hence in G2 there is a slightly better knowledge on the transmission pathways of Toxocara spp., even though most of the students admitted never to have heard of the term (Fig.15). 70% 60% 50% 40% 30% 20% 10% 0% unwashed vegetables and fruit not washing hands after working in the garden eating undercooked meat G1 G2 Fig.15 Possible answers about infection pathways of G1 and G2 (%) 23

24 100% 90% 80% 70% 60% 50% no pet cat and dog dog cat 40% 30% 20% 10% 0% through eating unwashed fruit and berries through eating unwashed candy, cookies and cakes not washing hand after petting a stray dog or cat through petting pet birds through not washing your hands after working in the garden through not washing your hands before a meal after working on the computer through eating insufficiently thermally treated meat Fig.16 Possible answers about infection pathways for Toxocara spp. from observed students (%) The graph above shows what the students believe the possible trasmission pathways of Toxocara spp. are. 90% of the students think that transmission occurs trough unwashed hands after petting a stray dog or cat, however, this is incorrect. Transmission of toxacariasis occurs by three options of the given answers, which are: by eating unwashed fruit and berries, in this case only 20% of the students were right. By not washing your hands after working in the garden, which was the second most common answer accounting for approximately 55% of the students. And the third correct answer for a possible pathway is by eating uncooked meat, just about 15% of students chose this option (Fig.16). There were no important discrepancies in each answer between students owning a cat, a dog, a cat and a dog and students having no pets. 24

25 14. CONCLUSIONS The research field of Toxocara spp. is very limited. Only in the last few years it has been brought to the attention that the amount of people infected with Toxocara spp., i.e.which were identified by seropositivity, are very high and especially in developing countries. The importance of this zoonotic infection should no longer be ignored. Assesing the most likely infection pathways by evaluating the risk, prevention and hand washing rountines adding the actual knowledge of parasite transmission pathways, I can say that there is a clear lack of education in the case of toxocariasis The majority of all students keep a pet. Taking each study programme separately, more than half of the students are pet owners, except for odontology students. The probability for acquiring Toxocara spp. is much greater if a dog or a cat is kept inside the house. G2 overall has more pets, leaving at a higher risk to get infected with Toxocara spp Medical faculty students have a higher probability to be infected if a dog or a cat is living inside at home compared to students from other study programmes. So what are the most likely infection pathways in this sample of students? Both medical faculty students as well as the other students of LSMU, they are most likely to be infected by parasite eggs spread to bed sheets, by contamination with soil or pet fur. Pets rummaging through personal belongings of their owners is the next highest risk factor on the list. Next factor is that cats and dogs are being allowed to move freely inside the house as well as outside. The least potential toxocariasis infection pathway is by ingesting fruit or vegetables contaminated with the parasite eggs As the prevention of further spreading of the parasite plays a vital role in managing the zoonotic infection, it was sad to see that more than half of the students do not regularly pick up their pet s faeces. This poses a risk for their own pet to be reinfected or other pets to be infected as well as the risk for the eggs to be distributed by soil. The same soil, which then can be accidentally ingested by humans, who did not properly wash their hands or fruit and vegetables. Additionally, the possibility to decrease the egg load in the environment is to give antiheminthic preparations to pets on a regular basis, following the recommended administration intervall, by ESCCAP, - every three months. Not even a fourth of the students follow these guidlines. In G1 case we can see that they are slightly better at actively reducing the amount of eggs of parasite in the environment. It s a vicous cycle, which can only then be broken if more people take it seriously the importance to pick up their pet s faeces and administer antihelminths preparations to their cats and dogs regularly. 25

26 14.4 As we have learned that transmission occurs by the faecal-oral route, hand washing is the essential way of personal prevention to aquire toxocariasis. The results show that students from G2 are better concerning the prophylactic measures such as washing their hands at appropiate times, such as washing hand before a meal, when they are visibly dirty and after working in the garden. Even though prophylactic measures are taken in most of the cases, the question still remains: do students take these actions to purposely prevent this zoonotic infection or do they just automatically follow the rules of general hygiene? The knowledge about toxocariasis infection pathways is the main key in understanding why hand washing after certain activities is so important. Looking at the level of knowledge among the observed students discussed in the conclusion below, this question is clearly answered The most interesting result of my research is that only one person from the whole sample of students could answer the question about infection pathways of Toxocara spp. correctly. Curiously, G2 seems to have a better knowledge about infection pathways than G1, even though G1 claimed to know infection pathways better. This means that the knowledge about toxocariasis of Lithuanian University of Health Sciences still is very little. This observation is very significant because all the students have some kind of a medical background. 26

27 15. REFERENCES 1. Gawor J, Borecka A, Marczyńska M, Dobosz S, Żarnowska-Prymek H. Risk of human toxocarosis in Poland due to Toxocara infection of dogs and cats. Acta Parasitol / Witold Stefański Inst Parasitol Warszawa, Pol [Internet] Mar [cited 2016 Jun 1];60(1): Available from: 2. Fan C-K, Liao C-W, Cheng Y-C. Factors affecting disease manifestation of toxocarosis in humans: Genetics and environment. Vet Parasitol. 2013;193: Amissah-Reynolds PK, Monney I, Adowah LM, Agyemang SO. Prevalence of Helminths in Dogs and Owners Awareness of Zoonotic Diseases in Mampong, Ashanti, Ghana. J Parasitol Res [Internet] [cited 2016 Jun 1];2016:1 6. Available from: 4. Liao C-W, Sukati H, D Lamini P, Chou C-M, Liu Y-H, Huang Y-C, et al. Seroprevalence of Toxocara canis infection among children in Swaziland, southern Africa. Ann Trop Med Parasitol [Internet] Jan [cited 2016 Jun 1];104(1): Available from: 5. Kroten A, Toczylowski K, Kiziewicz B, Oldak E, Sulik A. Environmental contamination with Toxocara eggs and seroprevalence of toxocariasis in children of northeastern Poland. Parasitol Res [Internet] Jan 19 [cited 2016 Jun 1];115(1): Available from: 6. Woodhall DM, Fiore AE. Toxocariasis: A Review for Pediatricians. J Pediatric Infect Dis Soc [Internet] Jun [cited 2016 Jun 1];3(2): Available from: 7. Strube C, Heuer L, Janecek E. Toxocara spp. infections in paratenic hosts. Vet Parasitol. 2013;193: Despreaux R, Fardeau C, Touhami S, Brasnu E, Champion E, Paris L, et al. Ocular Toxocariasis: Clinical Features and Long-term Visual Outcomes in Adult Patients. Am J Ophthalmol. 2016;166: Smith H, Holland C, Taylor M, Magnaval J-F, Schantz P, Maizels R. How common is human toxocariasis? Towards standardizing our knowledge. Trends Parasitol [Internet] Apr [cited 2016 Jun 1];25(4): Available from: Finsterer J, Auer H. Neurotoxocarosis. Rev Inst Med Trop Sao Paulo [Internet]. Instituto de Medicina Tropical de São Paulo; 2007 Oct [cited 2016 Jun 1];49(5): Available from:

28 &lng=en&nrm=iso&tlng=en 11. Deshayes S, Bonhomme J, de La Blanchardière A. Neurotoxocariasis: a systematic literature review. Infection [Internet] Mar 23 [cited 2016 Jun 1]; Available from: Fillaux J, Magnaval J-F. Laboratory diagnosis of human toxocariasis. Vet Parasitol. 2013;193: Overgaauw PAM, Van Knapen F. Veterinary and public health aspects of Toxocara spp. Vet Parasitol. 2013;193: Cassenote AJF, Lima AR de A, Pinto Neto JM, Rubinsky-Elefant G. Seroprevalence and modifiable risk factors for Toxocara spp. in Brazilian schoolchildren. PLoS Negl Trop Dis [Internet] [cited 2016 Jun 1];8(5):e2830. Available from: Rostami A, Ebrahimi M, Mehravar S, Fallah Omrani V, Fallahi S, Behniafar H. Contamination of commonly consumed raw vegetables with soil transmitted helminth eggs in Mazandaran province, northern Iran. Int J Food Microbiol [Internet] May 16 [cited 2016 Jun 1];225:54 8. Available from: Cardillo N, Rosa A, Ribicich M, López C, Sommerfelt I. Experimental infection with Toxocara cati in BALB/c mice, migratory behaviour and pathological changes. Zoonoses Public Health [Internet] May [cited 2016 Jun 1];56(4): Available from: Resende NM, Gazzinelli-Guimarães PH, Barbosa FS, Oliveira LM, Nogueira DS, Gazzinelli- Guimarães AC, et al. New insights into the immunopathology of early Toxocara canis infection in mice. Parasit Vectors [Internet] [cited 2016 Jun 1];8:354. Available from: Sager H, Moret CS, Grimm F, Deplazes P, Doherr MG, Gottstein B. Coprological study on intestinal helminths in Swiss dogs: temporal aspects of anthelminthic treatment. Parasitol Res [Internet] Mar [cited 2016 Jun 1];98(4): Available from: Macpherson CNL. The epidemiology and public health importance of toxocariasis: a zoonosis of global importance. Int J Parasitol [Internet] Nov [cited 2016 May 20];43(12-13): Available from: Frieden TR, Jaffe HW, Stephens JW, Thacker SB. Ocuar toxocariasis - United states, MMWR. 2011;60(22):

29 16. ANNEXES Hello, My name is Helene Tonner. I am a fifth-year student at the Medical Department of the Lithuanian University of Health Sciences. I am conducting research to identify toxocariasis infection pathways in children, teenagers and young adults, its consequences, and its prophylaxis. I would be very grateful if you could participate in this research and answer the following questions. Your answers will help understand attitudes towards: the arrangements of keeping pets in the home, the handling of pets, the importance of personal hygiene, the probability of animal-borne infectious diseases and pathways, and the importance of the prophylaxis of such diseases. The questionnaire should take minutes to complete. This questionnaire is anonymous. The data collected will be processed and presented in summary form only. The answers in this questionnaire will not be made available to the public. 1. Your age: (write number) 2. You are a: a. School student (grade\form): b. University student (faculty, programme, course (year)): 3. Is Kaunas your main place of residence? (write where) 4. Do you have, or used to keep a pet/ an animal? 5. If you currently do not have one, would you like to get one in the future? c. Not sure 6. Would your parents/guardians object to this? c. Not sure 7. What sort of animal would you like to get (please underline)? Squirrel, hamster, dog, cat, reptile, bird, spider, fox, rabbit, snake, other 29

30 If you have NEVER kept an animal in your home, please skip to question What animal(s) do you keep (please underline)? Squirrel, hamster, dog, cat, reptile, bird, spider, fox, rabbit, snake, other 9. If you do keep any dogs or cats, who is their principal owner? a. Father b. Mother c. Siblings d. Me e. Not sure 10. If you have any dogs, where are they kept? a. Outside the home b. Freely moving inside the home c. In a designated area inside the home d. Depends on the occasion e. No fixed abode 11. If a dog is kept in your living quarters, does it have its own sleeping place/cot? c. Not sure 12. If you have any cats, where are they kept? a. In a designated area inside the home b. In common areas of the home c. In the kitchen d. In the bathroom e. Depends on the occasion f. No fixed abode 13. Is the pet allowed to sleep in your room? c. Depends on the occasion 14. Is the pet allowed to sleep on your bed/pillow/under your sheets? c. Depends on the occasion 30

31 15. Is the pet allowed to lick your hands/face? c. Depends on the occasion 16. Is the pet allowed to rummage through/lie on your personal belongings (clothes, books, notebooks)? c. Depends on the occasion Pet Feeding 17. Are your pets allowed to hang around in the kitchen or sniff kitchen utensils? c. Depends on the occasion 18. What food do you give to your pet? a. Only designated pet food b. Designated pet food as well as home-made pet food c. Only home-made pet food d. Food that we eat ourselves e. Raw meat or its leftovers f. Raw fish or its leftovers g. A mixture of foods 19. Does your pet have a separate feeding dish? c. Not sure 20. Is the pet allowed on the food table? c. Not sure 21. Is the pet allowed to take food from its owner s plate? c. Not sure 31

32 Taking the pet for a walk/outside the home 22. Is your pet allowed to roam outside the home unattended (in playgrounds, streets, a park, a forest)? c. Depends on the occasion d. Not sure 23. Does your pet come into close contact with other unattended animals (e.g. stray dogs/cats)? c. Not sure 24. Is your dog taken on walks with a leash and muzzle? c. Depends on the occasion d. Not sure 25. Is your pet registered? c. Not sure 26. Are the droppings of your pet collected into special bags/dumped into designated bins? c. Depends on the occasion d. Not sure 27. Are items for collecting pet droppings (bags, scoops) easily available to you? c. Not sure 28. Are items for collecting pet droppings very expensive? c. Not sure 29. Does the area you live in have designated bins for animal droppings? 32

33 c. Not sure 30. Do you believe the quantity of the bins to be sufficient? c. Not sure 31. Does your cat defecate outside the home, or in a litter tray? a. Only outside the home b. Only in a litter tray c. Depends on the occasion d. Not sure General awareness and infection pathways 32. Do you know what a zoonosis is? b. Vaguely c. No 33. Are you aware of zoonosis infection pathways? b. Vaguely c. No 34. Do you know how you can get infectious diseases from diseased animals? b. Vaguely c. No 35. Do you know what diseases you can get from diseased animals? b. Vaguely c. No 36. Is the term toxocariasis known to you? b. Vaguely c. No 37. Are you aware of the existence dog and cat toxocariasis? b. Vaguely 33

34 c. No 38. Do you know how you can get infected with toxocariasis? b. Vaguely c. No Toxocariasis infection pathways 39. Underline, according to your understanding, possible toxocariasis infection pathways: a. Through eating unwashed fruits, berries and vegetables b. Through eating unwashed candy, cookies and cakes c. Through not washing your hands after petting a diseased stray dog or cat d. Through petting pet birds, such as canaries of parrots e. Through not washing your hands before a meal after working in the garden or playing in the sandbox f. Trough not washing your hands before a meal after working with a computer/speaking on the phone g. Through eating insufficiently thermally treated meat, fish, eggs, milk 40. What diseases can you get from diseased pets? Please list those that you know: Prophylaxis 41. Is the dog given a bath after being taken for a walk?, daily b. Yes, weekly c. Yes, monthly d. Yes, from time to time e. No, only the legs are washed f. No 42. What do you think is the most important purposes of giving the dog a bath/washing its legs? a. Keeping mud and dirt away from the room b. Keeping the carpets and furniture clean c. Droppings of other animals (strays, diseased animals) may be stuck to the fur/legs d. Parasitic protozoan cysts and worm eggs may be stuck to the fur/legs e. Canine ticks and fleas may be stuck to the fur/legs 43. Is the cat s litter tray cleaned and disinfected while wearing rubber gloves? 34

35 c. Depends on the occasion d. Not sure 44. Do you like to pet a cute little stray dog or kitten that you meet in the street? c. Depends on the occasion d. Not sure 45. Do you regularly take your pet to be inspected by a veterinarian? c. Not sure 46. Do you feed your pet antihelminthic medicines (e.g. worm pills)? c. Not sure 47. If yes, how often? a. Less than once a year b. Yearly c. More than once a year d. Every 3 months 48. Do you wash fruits, berries and vegetables that you have bought in a shop, or brought from a wood, garden or orchard before eating them? c. Depends on the occasion 49. When do you usually wash your hands? a. After using the bathroom b. Before preparing food and before a meal c. After cleaning the cat s litter tray d. After playing with your pet at home e. After taking your pet outside for a walk f. After work outside, in the garden or orchard g. When they are dirty 35

36 h. Other 50. In your opinion, is your knowledge of pet handling, care and toxocariasis prophylaxis both for your pet and your family members sufficient? c. Not sure 51. In your opinion, how could you gain/improve your knowledge regarding toxocariasis infection pathways and its prophylaxis? a. In school or university, from teachers, lecturers, guest lecturers, doctors, public health specialists b. In the home, from parents, grandparents, siblings or other relatives c. In the street, from friends and neighbours d. In the media, through the Internet, TV, radio shows, newspapers, leaflets e. Other: Thank you for your answers and your time Respectfully, Helene Tonner Fifth-year student at the Medical Department of the Lithuanian University of Health Science 36

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