290 likes | 708 Views
OIE Global conference on Rabies control Assuring quality and sustainability of rabies dog vaccination programme: vaccination – rabies surveillance post vaccination monitoring. Florence Cliquet – Jacques Barrat. Nancy Laboratory for Rabies and Wildlife . WHO Collaborating Centre
E N D
OIE Global conference on Rabies control Assuring quality and sustainability of rabies dog vaccination programme: vaccination – rabies surveillance post vaccination monitoring Florence Cliquet – Jacques Barrat Nancy Laboratory for Rabies and Wildlife WHO Collaborating Centre for Research and Management in Zoonoses Control OIE Reference Laboratory for Rabies European Union Reference Laboratory for Rabies European Union Reference Institute for Rabies Serology 7 - 9 September 2011 Incheon-Seoul, Korea
Key points • Final objective of control measures: prevention and elimination of the disease in Humans. • Mass vaccination of dogs is the most successful method for control and possibly elimination of dog mediated rabies (WHO, 2005). • The theoretical level of vaccination coverage should be at least 70% (WHO, 2005) to lead to an average 0 incidence in both humans and animals. • Given the high turnover of many dog populations, all dogs should be vaccinated, puppies (<3 months) included (Cliquet et al, 2001).
Main prerequisites for dog rabies control programmes:an integrated approach • National network gathering one body of each involved sector – Identification of one body responsible of the programme. • Legal basis and long time budget allocation • Strategy of control – planning • Ensuring coordination between all actors: Precise identification of each step of the programme: who is responsible of what and when. • Dog demography information (both owned and stray) and dog ecology • Ensuring availability of biological products • Education of the public (in bite prevention & rabies awareness) – Strong media support • Trained diagnostic laboratory • Active surveillance network • Evaluation of control programme
International available guidelines • WHO Expert Consultation on Rabies, WHO Geneva, WHO Technical Report Series, 2005, n°931, 87 p. • Rabies chapter (2.1.13) of OIE Manual, 2011, oral vaccination paragraph. • Oral vaccination of dogs against rabies, WHO, Geneva 2007. • Stray dog population control, Terrestrial Animal Health Code, chapter 7.7, OIE 2011. • Blue print for rabies prevention and control (rabiesblueprint.com). • … and numerous reports of WHO Expert consultations.
Legal basis and budget allocation • Rabies should be a notifiable disease both for humans and animals • National laws as well as regional and local legislation and decisions, according to country administrative organization • Technical and administrative responsibilities clarified before the campaign • Costs calculated for each sector involved and long term funding insurance • Rabies should be a notifiable disease both for humans and animals • National laws as well as regional legislation and decisions, depending upon country administrative organization
Network with all involved sectors(“one health” concept) • National Rabies Control Committee, generally chaired by representative of Agriculture Authority and gathering representatives of : • Ministry of Agriculture, Ministry of Health, Ministry of Education, Ministry of Interior Affairs, Ministry of Environment, Head of Rabies National (Reference) Laboratory, Animal Welfare associations and NGOs, Veterinary services and private veterinarians. • Objectives: • Information and exchange (regular meetings), coordination of different activities for rabies prevention and control, in case of rabies outbreak or problem arising, decision taken after collaborative discussion.
Intersectoral coordinationDefining main responsibilities at national,regional and local level
Defining the strategy of control 1/2 • Assessment of the current epidemiological situation – Knowledge of dog population ecology • Parenteral vaccination of dogs: • Person responsible of vaccination plan • Mass vaccination campaign? Hot spots? Limited area? Oral vaccination? Dog identification? • Vaccine used and cold storage places • Teams involved and training for “vaccinators” and dog “catchers” • Material used (syringes, needles, lassos…) • Model of grids to complete • Period of time and frequency of vaccination campaigns • Practical organization in the fields
Defining the strategy of control 2/2 • Dog population management (if any – ABC programmes, garbage management, …) • Rabies surveillance: • Person responsible for surveillance • Practical organization in the fields • Model of grids to complete • Evaluation of the programme: • Person responsible for evaluation • Method used for evaluation and frequency of evaluation
Categorization of dogs (who, 2007) None Semi Full Restriction None Feral dogs Neibourhood or community dogs Semi Restricted or supervised dogs Full Family dogs Dependency • Ecological survey (questionnaires) conducted prior to the strategy elaboration to identify needs in management of dog population and to determine the method of vaccination (interest of oral vaccination in the campaign)
Immunological response to vaccination • Vaccination against rabies with injectable vaccines induces a humoral response with the production of rabies neutralising antibodies. Latency Exponential increasing Plateau Decreasing Level of antibodies Vaccination Time after vaccination In cats and dogs, the peak of rabies neutralising antibodies is generally reached between 4 to 6 weeks after first antigenic stimulation.
Rabies vaccines for dogs: Injectable vaccines • WHO and OIE recommendations • Cell culture produced • Inactivated • Adjuvanted • Possibly combined with other antigens • Potency : 1.0 IU/dose • Quality controls have to be performed to guarantee: • Safety: control of the inactivation process • Stability: during long storage and under • liquid or lyophilized forms • Efficacy: • Potency test: NIH test or Pharmacopeia test (Rabies vaccine (inactivated) for veterinary use, 2008, 451). • Immunogenicity on 35 animals (serological survey and challenge study).
Central point parenteral vaccination • Intended for domestic dogs which have affiliations (family or community dogs) • Considered as the most cost effective strategy (Kaare et al, 2009; Zingstag et al, 2009) • Requires owner’s participation • Requires engagement of local authorities and public awareness • Vaccination of dogs against rabies and possibly other diseases • Possible identification of dogs (plastic collars or coloured tags) • Possible dog vaccination card/certificate
House to house parenteral vaccination VET LAB • Intended for domestic dogs which have affiliations but less accessible (aggressive dogs and dispersed community dogs) • Requires: • detailed organizations (maps) • dog owners being present at home • engagement of local authorities and public awareness • Possible: • Vaccination of dogs against rabies and possibly other diseases • Possibly identification of dogs (plastic collars or colored tags) • Possibly dog vaccination card/certificate
Oral vaccination of dogscombined to parenteral vaccination • The major obstacle in rabies control is the accessibility to vaccination of inaccessible owned and ownerless dogs • Since 1988, WHO has elaborated several guidelines and recommendations (last ones in 2009) for encouraging the launching of studies on oral vaccination in combination with parenteral vaccination • Trials undertaken in East Europe, Asia and Africa using commercial vaccine baits intended for wildlife immunization
Oral vaccination of dogs Potential of Oral versus Parenteral vaccination according to dog population structure 100% Immunization coverage: 60 - Oral vaccination combined or not with PV 20 20 --- 80 40 --- 50 80% - Parenteralvaccination 50% 65 --- 75 ownerless 20 --- 40 45 owned & unaccessible owned & accessible TUN YEM TUR Dog population (segments in %) Proportion of restricted dogs (accessible and not) Slide kindly given by Dr. F.X.Meslin
Oral vaccination of dogscombined to parenteral vaccination • Commercial vaccine baits available • Considerations regarding: • Method of bait distribution (house to house, central places, wildlife model) • Baits attractiveness in local conditions (pilot studies) • Vaccine bait efficacy in local conditions (pilot studies) • Safety requirements for candidate vaccines • Assessment of vaccination efficacy : dog vaccination coverage in the field, monitoring rabies incidence
General organisation of vaccination campaigns Schematic representation of vaccination areas TEAM 4 Team 1 Team 6 • Caption: • Contamination • between areas because • of one deficient team • Rabid dog Team 2 Team 7 Team 5 Team 3 Team 8 • All teams vaccinated correctly dogs except for team 4. • Team 4 had not a methodical organization of vaccination. Result: too large areas insufficiently vaccinated.
Dog population management • Sanitary measures: • Culling (not recommended, not efficient and humanely unaccepted): only limited to suspected rabid dog or unvaccinated contact dogs • Temporary removal (adoption programmes) • Waste management • Reproduction control: • Animal birth control programme • Sterilization or immunocontraception tools (WHO, 2009)
Epidemiological surveillance • Rabies surveillance is the basis for any control and prevention programme • Surveillance based on laboratory investigation on brain of dead or sick animals (not on killed at random dogs) • No sample size – Animals must be sampled from all parts of the country and all along the year • Routine reference diagnostic test (WHO, 1996; OIE, 2011): • Antigen detection (FAT): gold standard test • Virus isolation RTCIT / MIT if cell cultures are not available • Viral genome detection • Virus typing: Mabs or molecular methods
Example of rabies surveillance network Such network must have a legal basis (legislation article) National competent authority for animal health National reference Laboratory for rabies EFSA, WHO / OIE (Rabnet and WAHID* database) National rabies database (all diagnosis negative and positive results from both animals and humans) Regional Lab Veterinary services *http://web.oie.int/wahis/public.php?page=home Veterinarians National competent authority for human health Citizens, NGOs, associations, founding an animal cadaver or a suspect live animal Caption Sending of samples Sending of results
Evaluation of control programme • Ultimate indicator of the success of vaccination programme: decrease in rabies incidence in vaccinated areas both in humans and animals • Animal bite injury from hospitals • The strategy must be rapidly changed or adapted in case rabies incidence remains unchanged despite vaccination. The main reason is generally an insufficient vaccination coverage. • It is therefore advised, if budgets are limited, to analyse the entire programme for improvement and possibly to decrease the surface of the area of vaccination
Reported and estimated vaccination coveragesin domestic dog populationsfrom various settings in sub-Saharan Africa since 1990 From Lembo et al., 2010
Cases of rabies in dogs and number of vaccinated dogs in Mexico 1990-2004 Vaccinated dogs (Millions) Rabies cases in dogs Slide kindly given by Dr. F.X.Meslin
Vaccinated domestic carnivore Domestic carnivorein contact with a rabidanimal thenvaccinated Vaccinated domesticcarnivore then in contact with a rabid animal Around 30 days Production of rabiesneutralisingantibodies Serological survey following vaccinationtion • Performed on a defined number of dogs • Blood sampling at D0 and D30 on each dog to be tested • Analysis using FAVN test or RFFIT (threshold 0.5IU/ml) Variation in duration of the incubation period A dog withoutantibodiesat Day x maybeprotected if seroconversionwasachievedbefore Day x.
Serological follow up of dogs vaccinatedwith a local cell culture inactivatedand adjuvanted vaccine Day 30 Day 0 (Unpublished Anses data – serological survey done in Morocco)
Conclusion • To be sustainable, rabies control programmes based on vaccination of dogs should be integrated in a multiannual project of rabies elimination. • Mass dog vaccination programs using injectable vaccines are successful for rabies control in different places (e.g. Latin America, Bohol, Bali, KwaZulu Natal, Sri Lanka). • Priority of government for rabies control is the main prerequisite associated with long term funding insurance. • Oral vaccination trials should be undertaken in those areas where rabies control using injectable vaccines is a success to increase the vaccination coverage. • Importance of GARC, PRP and Rabies Elimination Demonstration projects.