OIE laboratory network on diseases of camelids Final report

Size: px

Start display at page:

Download "OIE laboratory network on diseases of camelids Final report"

Georgiana Stevenson
5 years ago
Views:

1 1 Expert workshop OIE laboratory network on diseases of camelids Final report Teramo, Italy. October, 21-22, 2011 International Training Centre for Veterinary Training and Information Francesco Gramenzi

2 2 Opening and purposes of the meeting This workshop was intended to be an exploratory meeting, aiming at setting up rules and procedures to activate a network of laboratories for diseases of camelids, whose need was expressed by the OIE ad hoc group on this issue and confirmed by the OIE Biological Standards Commission. The network should build up processes and tools to facilitate the fight against the most important diseases of camelids, to exchange information and to standardize and validate diagnostic tests according to the OIE Terrestrial Manual. The objectives of the workshop were: to review the major outcomes of the last meeting of the OIE ad hoc group on diseases of camelids; to share and discuss objectives, rules and procedures to activate an OIE laboratory network on diseases of camelids; to prepare a working plan to achieve the network implementation in a short term provision. The meeting was chaired by Dr. Mehdi El Harrak. Rapporteurs were appointed for each session. Ms Barbara Alessandrini presented the main activities and tasks of Istituto G. Caporale (ICT). Copy of the presentation is reported in Annex 2 (ppt presentations). Prof. Vincenzo Caporale welcomed the participants to the meeting and recalled the purpose of ICT to support the work of the OIE Laboratory Network on diseases of camelids. He also offered the ICT diagnostic facilities and expertise to enhance the network activities, within the remits of its OIE collaborating centers and reference laboratories. Dr. Mehdi El Harrak thanked Prof. Caporaleand presented the meeting agenda. The Agenda was adopted. Agenda and list of participants The workshop agenda and the list of participants are described in Annex 1. Conclusions and recommendations of the meeting of OIE ad hoc group on diseases of camelids (Paris, 3-5 May, 2010) Dr. Mehdi El Harrak reported the main conclusions and recommendations of the last meeting of the OIE ad hoc group on diseases of camelids (Annex 2). The implementation of the OIE laboratory network for diagnosis of diseases of camelids was a strong recommendation of the OIE ad hoc group. He also underlined the importance of camelids in the economy of arid areas and the reasons leading the OIE to establish the OIE ad hoc group on diseases ofcamelids, which met twice in 2008 and 2010.The group analyzed the specific constraints for disease diagnosis and control in camelids. Camelids diseases were shared in three categories: significant diseases, diseases for which camelids are potential carriers, minor diseases. Viral, bacterial and parasitic diseases were consideredfor each category: dromedary camels, bactrian camels, and New World camels.

3 3 Setting of priorities Duringthis workshop the attention was focused only on priority diseases of dromedary camels, hereinafter referred as camels. The role of camels in the epidemiology and transmission of several diseases and their susceptibility still need to be assessed. Diagnostic methods need to be validated in camels. Specific diagnostic kits should be developed. Existing vaccines must be validated in camels (e.g. brucellosis, rabies, RVF). There is a need for establishing a network for the: exchange of information, identification of regional leading laboratories, validation of diagnostic methods in camels, organization of proficiency testing. The members of the network will be: OIE reference laboratories for priority diseases, associated research laboratories, laboratories in camels rearing countries. It is also necessary to get reliable data on camels health status, to identify the main diseases and their economic importance, and risk factors linked to the disease spreading. Validation of diagnostic methods for viral diseases in camelids Chairman: Dr Mehdi El Harrak Rapporteur: DrAbdelmalikKhalafalla Dr Mehdi El Harrak (ME) reviewed the list of camelid diseases prepared by the ad hoc group in Participants discussed viral diseases and made the following recommendations: 1. Camelpox: Camelpox is the most important camel disease. Dr ME briefed the meeting on a recent publication from India (Bera et al., 2011) that described the first conclusive evidence of zoonotic camel pox virus infection in humans associated with outbreaks in dromedary camels during The ad hoc group will inform OIE about the new findings and proposedto carry out a survey to detect human camelpox cases in camel rearing areas of the world. The meeting also pointed out the opportunity to suggest a global program to eradicate camelpox. 2. Camel contagious ecthyma (CCE): Recent publications on outbreaks of this disease in Bahrain and India were reviewed. As ICT has some experience with parapox virus, participants recommended that infected materials from Sudan and Mauritania are sent to ICTfor diagnosis and genotyping. It was also advised thatict, in collaboration with national laboratories and members of the ad hoc group, will develop a multiplex PCR protocol to differentiate the three clinically similar exanthematous camel diseases:camelpox, CCE, and camel papillomatosis. 3. Rabies: the group discussed test reliability, to understand which test can be used to monitor immune response after vaccination in camels. It was recommended that ICTwill collaborate in validating serum neutralization or indirect immune-fluorescent techniques for rabies and test the anti-camel conjugate produced by BIOX (Belgium) in comparison to other commercially available anti-camel conjugates. 4. Rift Valley Fever (RVF):therecent RVF outbreaks in Mauritania, with the involvement of camels, in whichigm antibodies were detected (El Mamy et al. 2011), and successful virus

4 4 isolation from camel specimens, were underlined and discussed. It was recommended that the virus isolated from camels in Mauritania should be sent to ICT, to be used for the preparation of inactivated vaccines and diagnostic reagents. 5. African horse sickness and other orbivirus infections: results of a recent serological survey for antibodies against some viruses in camels of Morocco were reviewed. General recommendations: after discussing the importance of infectious diseases in camels, the meeting attendees recommended to randomly collect about 1000 camel sera from Sudan, Tunisia, Mauritania, Morocco and Syria and test them collectively in ICT, to investigate seroprevalence of the most important viral and bacterial pathogens. Protocols and guidelines for serum collection and dispatch to ICT will be prepared and distributedby ICTwithin the first week of December to the national laboratories in the above-mentioned countries. It was also recommended that ICT, in collaboration with national laboratories,should develop and test anti-camel immunoglobulins andconjugate and prepare negative and positive control sera for the most important viral and bacterial infections. Validation of diagnostic methods of bacterial, parasitic and fungal diseases in Camelids The collection of 10 to 20 positive samples for selected bacterial diseases(listed below) was recommended. The following diseases were considered: 1. Brucellosis: validation of tests for Camelids. One validation is in process in Argentina using lama sera.positive controls may be provided by United Arab Emirates. Negative controlserawill be collected by ICT from zoo animals in Europe or in the USA. 2. Pasteurellosis:the highest possible number of samples should be collected in slaughterhouses. Deeper investigations should be carried out by national laboratories or OIE reference laboratories. 3. Tuberculosis: slaughterhouse monitoring with a standardised protocol, should be carried out. Test validation is recommended. 4. Trypanosomes:T. evansishould be included in serological investigations. ICT is also interested to acquire T. evansipositive samples from the field and laboratory strains in order to improve diagnostic capability and to studyserological interactions and genetic differences between T. evansi and T.equiperdum. Vaccine validation protocols Basic protocols for the validation of vaccines in camels were discussed. Five priority diseases were considered: rabies, RVF, BT, brucellosis, pasteurellosis.

5 5 Rabies RVF BT Brucellosis Pasteurellosis Vaccination recommended for intensive farms, in suburban areas and leisure animals. No mass vaccination. recommended in endemic area. in intensive farms, leisure animals and for trade purposes. Type of vaccine inactivated Clone 13 vaccine (live-attenuated) one inactivated vaccine among the available ones (BTV1, BTV8, BTV4) Rev-1 vaccine inactivated (P. haemolitica and P. multocida) N. of animals 10 negative animals (8 vaccinated + 2 controls). Include 2 pregnant females and 2 dairy camels. 10 (8+2 controls). Include pregnant and dairy animals. 6 (4+2 controls). Include 2 pregnant females and 2 dairy camels. 10 (8+2 controls). Include 2 pregnant and 2 dairy animals. 6 (4+2 controls) Gender and age adult animals, intermediate size. Dairy camels could be considered for the evaluation of effects on milk production. 4 young and 4 adults adult negative animals 4 young and 4 adults young animals Injection routes s.c. / i.m. as recommended by the manufacturers Followingmanufacturerinstructions s.c./i.m. s.c. s.c. / i.m. Doses 2 doses (bovine dose and double dose two subgroups of 4 animals) cattle dose according to the manufacturer instructions cattle dose according to the use of vaccine in cattle cattle dose Booster injection between 4 weeks and 3 months no booster doserequired 3-4 weeks according to manufacturer instructions no booster dose required 1 month after first dose

6 6 Laboratory tests weekly testing by VN and IF, till 1 month after booster dose. After 1 year, ifpossible. till 6 weeks after the injection. ELISA and VN. Weekly testing. Also virological testing: PCR and isolation to evaluate possible viraemia. weekly. ELISA and VN. PCR RBT and CFT. Weekly. Bacteriological and PCR examination of milk and aborted foetus (if any). ELISA must developed and checked in laboratory animals Side effects safety controls, evaluation on milk production and reproductive problems and on pregnancy. on pregnancy and milk production. safety controls, evaluation on milk production and reproductive problems and on pregnancy. Abortion, milk excretion general safety Challenge nochallenge Assure biosecurity and biosafety measures according to international standards. yes. Evaluation of viraemia after challenge. Clinicalscoring. no challenge no challenge Duration 10 weeks (starting 2 weeks before first injection). Possibly control after 1 year from vaccination. 8 weeks weeks. 2 months 8 weeks

7 7 The following countries offered to perform the vaccination experiments: Rabies: Sudan RVF: Mauritania BT: Tunisia Brucellosis: Sudan Pasteurellosis: Morocco Conclusions and recommendations The participants agreed on the proposal to carry out a survey based on the collection of at least 1000 sera from each country (5000 in total, countries involved: Morocco, Mauritania, Tunisia, Sudan, Syria). The sera will be sent to ICT to be tested against the main priority diseases (camelpox, RVF, Orbiviruses, PPR, brucellosis). ICT will also organize a laboratory training period for each partner, during which sera will be tested jointly with the ICT personnel. Tested samples will be distributed to the laboratories of the participating countries for a quick performance evaluation. The experience will also allow a preliminary validation of the available diagnostic tests. Sera will be collected in 2012 and they will be dispatched to ICT before the end of July Testing sessions coupled with in-lab training will be performed in the early autumn Results will be evaluated during the next meeting of the network. True negative samples for test validation will be collected by ICT in Italian zoos. ICT will produce an anti-camel polyclonal conjugate. The participants agreed to start with the validation of laboratory methods for camelpox. ICT will prepare a detailed action plan within the first week of December In relation to vaccine validation the participating countries will prepare a detailed project, specifying resources, timing and costs, which will be sent to the coordinator Dr Mehdi El Harrak and the workshop secretariat (ICT). Next meeting is planned on November-December 2012.

A LABORATORY NETWORK FOR DIAGNOSTIC OF CAMELIDS DISEASES

A LABORATORY NETWORK FOR DIAGNOSTIC OF CAMELIDS DISEASES M. EL HARRAK Chair of OIE ad hoc Group on Camelids Diseases Biopharma Lab BP 4569 Rabat Morocco CAMELIDS FAMILY Dromadary Camel Bactrian Camel Lama