EPIDEMIOLOGY OF TOXOPLASMA GONDII INFECTION OF CATS IN SOUTHWEST OF ALBANIA SHEMSHO LAMAJ 1 GERTA DHAMO 2 ILIR DOVA 2 1 Regional Agricultural Directory of Gjirokastra 2 Faculty of Veterinary Medicine, Agricultural University of Tirana, Albania ABSTRACT The present study assessed the prevalence of Toxoplasma gondii infection in household referred cats to private animal clinics in Gjirokastra and Tepelena using modified agglutination test (MAT). Cats are the natural reservoir of Toxoplasma gondii and excrete the resistant oocyst to environments. The objective of this study was to investigate the epidemiology of toxoplasmosis in household cats in Southwest rural environment of Albania. A total of 138 cats from different Gjirokastra and Tepelena areas were surveyed. The overall prevalence of T. gondii infection was 42 % (58/138); by gender, 45.6 % (26/57) in males and 40.0 % (32/81) in females. Cats more than 3 years had the highest infection rate (63.4%). The outside cats were more prone to infection than indoors. The prevalence of T. gondii antibodies in 42% of cats suggests wide-spread contamination of the rural environment with oocysts. KEYWORDS: Seroprevalence, Risk factors, Cats, Toxoplasma gondii INTRODUCTION Toxoplasmosis is a zoonosis that affects both animals and humans world-wide. This disease is of economic importance in regard to animal reproduction, and has become a public health concern since it leads to abortions and neonatal complications in humans. The definitive host for T. gondii is cat and the intermediate hosts are mammals and birds. People can get infected by ingestion of tissue cysts with raw or undercooked meat, and by ingestion of oocysts with water, vegetables or soil (Dubey and Jones, 2008). It has been suggested that T. gondii infection with oocysts is more serious than infection with tissue cysts (Dubey, 2009). Cats play an important role in the spread of toxoplasmosis because they are the only animals that excrete resistant oocysts into the environment (Silva et al, 2001). In Albania, large numbers of stray cats are found roaming the streets, fresh markets, public places. These stray cats act as sources of many zoonotic diseases, such as rabies, catscratch disease, ehrlichiosis and toxoplasmosis. Usually the presence of antibodies rather than 76
oocyst shedding is detected. The standard diagnosis of toxoplasmosis in cats is based on coprological diagnosis. Serological surveys for the detection of anti-t. gondii antibodies in cats was used to assess the degree of environmental contamination as the antibodies persist and indicate prior exposure to T. gondii (Miro et al., 2004). In the present study, the prevalence of T. gondii in cats from different Gjirokastra and Tepelena rural areas was investigated using the modified agglutination test (MAT). The objective of this study was to investigate the epidemiology of toxoplasmosis in household cats in southwest rural environment of Albania. MATERIALS AND METHODS Study population Serum samples were obtained from cats in some private clinics while the cats were under general anesthesia for surgery. The cats were presented to the private clinics in different rural and urban areas of Tepelena and Gjirokastra. The cat populations were divided into indoor cats and outside or in out cats. The barn cats were those that lived in barns and were handled by the owners of the farms. The outside or in out cats were those that were handled, lived inside the house or outside, and were up-to-date in their vaccinations. Serological assay A total of 138 cats (53 household and 85 outside or in out cats) of various ages and of both sexes were referred to private animal clinics of Tepelena and Gjirokastra, from October 2012 to January 2014 for various ailments. Their blood samples were collected from Jugular veins. These blood samples were left for about an hour for blood clotting to occur. The clotted blood was then separated with a fine loop immediately and was centrifuged at 3500 rmp for 10 minutes. The separated sera were stored at 20 C until assayed. Sera were diluted 1:25, 1:50, and 1: 500 with phosphate buffer saline and tested by the modified agglutination test (MAT), as described by Dubey and Desmonts (1987). On the basis of extensive evaluation in cats fed tissue cysts, a titer of 1:25 was considered indicative of T. gondii infection in cats (Dubey and Thulliez, 1989; Dubey et al., 1995; Dubey et al., 1995a, 1995b). RESULTS Toxoplasma gondii antibodies were detected in 58 (42%) of 138 cat blood samples. The prevalence of T. gondii infection was highest in cats >3 years old (63.4%) (Table 1). The 77
proportion of females (40.0%) testing positive for T. gondii antibodies was not significantly higher than that of males (45.6%) (P < 0.05). Table 1. Prevalence of T. gondii antibody and the MAT titers in cats in study areas Sex No. No. (%) No. of cats with antibody in titers Tested cats Positive 1:25* 1:50* 1:500* Male 57 26 (45.6) 2 (3.5) 6 (10.5) 18 (31.6) Female 81 32 (40.0) 4 (5.0) 7 (8.6) 21 (25.9) Total (%) 138 58 (42.0) 6 (4.4) 13 (9.4) 39 (28.3) * Serum dilution The prevalence of T. gondii infection was highest in cats >3 years old (63.4%) (Table 2). The seropositivity rate of Toxoplasma gondii in young and adult cats showed that there is a relationship between seropositivity and age (p> 0.05). Table 2. Seroprevalence of Toxoplasma gondii antibodies in cats according to age Age of cats Number of No. (%) No. of cats with antibody in titers cats tested Positive 1:25* 1:50* 1:500* Juvenile, >6-12 months 44 7 (15.9) 0 2 (4.6) 5 (11.4) Young adult, >12-36 months 53 25 (47.2) 2 (3.8) 5 (9.4) 18 (33.9) Adult, >36 months 41 26 (63.4) 4 (9.8) 6 (14.6) 16 (39.0) Total (%) 138 58 (42.0) 6 (4.4) 13 (9.4) 39 (28.3) * Serum dilution The seropositivity rate of Toxoplasma gondii increased with age. The outside cats were more prone to infection than indoors (Table 3). Table 3. habitat Seroprevalence of Toxoplasma gondii antibodies in cats according to Number of No. (%) No. of cats with antibody in titers Habitat cats tested Positive 1:25* 1:50* 1:500* Household 53 17 (32.1) 1 (1.9) 5 (9.4) 11 (20.8) Outside 85 41 (48.2) 5 (5.9) 8 (9.4) 28 (32.9) Total (%) 138 58 (42.0) 6 (4.4) 13 (9.4) 39 (28.3) * Serum dilution 78
Table 4. Factors associated with T. gondii infection in cats of Tepelena and Gjirokastra rural and urban areas Factors No. of positive (%)/ Odds ratio p-value Chisquare df Age group No. of sample (95 CI) 0.134 7.033 2 Juvenile, >6-12 months 7/44 (15.9) 1 Young adult, >12-36 25/53 (47.2) 2.96 (1.17-7.50) Adult, >36 months 26/41 (63.4) 1.08 (0.55-2.11) Sex 0.474 0.55 1 Male 26/57 (45.6) 1 Female 32/81 (40.0) 1.28 (0.65-2.55) Habitat 0.001 11.22 1 Household 17/53 (32.1) 1 Outside 41/85 (48.2) 3.11 (1.58-6.12) Total 58/138 (42.0) DISCUSSION The present study examined samples collected from different rural and urban areas of Tepelena and Gjirokastra. The prevalence of T. gondii antibodies in 42% of cats suggests wide-spread contamination of the rural environment with oocysts. The prevalence of T. gondii in cats was found to vary depending on the age group, habitat, density of animals in the district and the economic status of people living in that area. In our study the rate of positive female cats was not significantly lower than male cats (P<0.474). In most surveys, the sex of dogs was not significantly associated with seroprevalence, as has been reported by other researchers (Dubey, 1985; Ali et al., 2003). On the other hand, the rate of seropositive female cats was significantly higher than that of seropositive male cats. In Japan, no significant differences were observed in the seroprevalence of T. gondii in both the sexes of cats (Maruyama et al., 2003). The genderbased differences in seroprevalence between stray dogs and cats in Albania are presently unclear. Most cats in Albania are raised either outdoors or both outdoors and in- doors. The prevalence of T. gondii infection in indoor cats is normally lower than in outdoor cats (Dubey and Beattie, 1988). Stray cats are infected by eating infected rodents (Dubey and Beattie, 1988) or through oocyst contamination of the environment. Since infected stray cats are capable of shedding oocysts in public places, other animals and humans may become infected due to contamination of the environment. The results of this study have confirmed that outside or in-out cats 41 (48.2 %) had tendency to have higher seroprevalence than cats kept indoor 17 (32.1 %), odd ratio is significantly higher in cats kept outdoor. This may be due to the reason that outside or in-out 79
cats could have licked up the infection through catching of wild rodents, birds, reptiles, raw food scraps etc as reported by Dubey (2004). In the previous study, of 146 domestic cats surveyed in Tirana during 2008 through 2010, antibodies to T. gondii were found in 91 cats (62.3%), and antibodies were measured by the indirect fluorescent antibody test (IFAT) (Silaghi et al., 2014). In our study, the overall seroprevalence of Toxoplasma gondii in cats 42 percent was lower than that of stray cats 91 (62.3 %) and adult cats 26 (83.9 %) reported by Silaghi et al. (2014) in Tirana. This variation is probably related to differences in the timing of the studies, the environmental conditions responsible for the dissemination of T. gondii infection (Dubey and Beattie, 1988), season of sampling and differences of sensitivities and specificities of used tests and the distribution of samples. The high prevalence of T. gondii antibodies in the cats from Tirana, Albania, is certainly related to their origin from suburban habitats with constant access to the outdoors, which has been identified as a risk factor of the infection (Györke et al., 2011). In conclusion, we suggest that cats have an important role in contamination of environment to oocysts but it is not clear whether they have being infective by ingestion of oocysts or by eating the meat of intermediate host especially small rodent and birds. Some studies on such intermediated host are necessary in this region. This study emphasizes the potential role of stray cats and outside or in-out cats as a source of toxoplasmosis transmission to humans in Albania. This information is important for public health, because cats are one of the most popular pets in Albania and frequently come into close contact with humans (Frenkel et al, 1995). These cats may contaminate the environment, thus exposing humans, and particularly children, to possible T. gondii infection. REFERENCES 1. Ali, C.N., Harris, J.A., Watkins, J.D., Adesiyun, A.A., 2003. Seroepidemiology of Toxoplasma gondii in dogs in Trinidad and Tobago. Vet. Parasitol. 113, 179 187. 2. Dubey, J. P. and G. Desmonts (1987). Serological responses of equids fed Toxoplasma gondii oocysts. Equine Vet. J. 19: 337 339 3. Dubey JP, Beattie CP. Toxoplasmosis of animals and man. Boca Raton, Florida: CRC Press, 1988: 1-220. 4. Dubey, J. P. and P. Thulliez (1989). Serologic diagnosis of toxoplasmosis in cats fed Toxoplasma gondii tissue cysts. J. Am. Vet. Med. Assoc.194: 1297-1299. 5. Dubey, J.P., 1995. Duration of immunity to shedding of Toxoplasma gondii oocysts by cats. J. Parasitol. 81, 410 415. 6. Dubey, J. P., M. R. Lappin, and P. Thulliez. 1995a. Diagnosis of induced toxoplasmosis in neonatal cats. Journal of the American Veterinary Medical Association 207:179 185. 7. Dubey, J. P., M. R. Lappin, and P. Thulliez. 1995b. Long-term antibody responses of cats fed Toxoplasma gondii tissue cysts. Journal of Parasitology 81:887 893. 8. Dubey, J. P. (2004). Toxoplasmosis a waterborne zoonosis. Vet. Parasitol. 126: 57 72. 80
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