Specific measures to demonstrate vaccine effectiveness should include prior knowledge of the potency and match of the vaccine used, accurate numerator and denominator data on the vaccinated population, evidence of an effective storage and distribution network including cold chain maintenance, good records of doses used and of vaccine
coverage, and direct demonstration of the quality of immunity induced in vaccinated animals. This information can be collated and analysed to predict its effect in disease spread simulation models to provide a strong baseline to which Crizotinib ic50 further evidence from a serosurvey can be added to substantiate freedom from infection. The procedure for ABT-199 clinical trial recognition
by OIE of the status of FMD-free where vaccination is practised requires applicants to provide evidence of vaccine effectiveness, including data on population immunity arising from immunisation campaigns. This requirement is absent from applications for recovery of the status of FMD-free where vaccination is not practised following use of “vaccination without subsequent slaughter” [19]. However, random surveys to monitor population immunity are relatively simple to perform in terms of both sample collection and sample testing, since farm visits to inspect vaccinated herds will already be part of the sanitary control measures and because validated tests for SP antibodies are widely available. crotamiton Another measure would be to undertake a heterologous in vivo vaccine potency test to directly show the level of protection provided by the vaccine used against challenge with the virus causing the outbreaks that are to be controlled. Such potency tests have been considered not worthwhile, as they are too slow to inform a decision on whether or not to proceed with vaccination. However, results
could support the downstream application for FMD freedom, as well as assisting the interpretation of serosurvey findings aimed at demonstrating effective vaccine induced population immunity. As a minimum, sera could be obtained from vaccinated animals and tested serologically against the outbreak virus to show the degree of in vitro protection from which in vivo protection could be estimated. In this paper, we review the approaches that can be taken to improve the use and interpretation of serosurveillance using FMDV NSP tests. Even though NSP tests that can differentiate infected from vaccinated animals have become available, countries are reluctant to use emergency vaccination as an additional control measure if FMDV is introduced.