Available data to analyse
Introduction
The African horse sickness (AHS) sentinel surveillance program is aimed at providing additional confidence of AHS freedom in the AHS free and AHS surveillance zone. Serological sentinel surveillance candidates are selected based on their history of a lack of AHS vaccination while PCR candidates do not need to adhere to this requirement. In the initial phases of the program vaccinated horses/horse of unknown vaccination were also selected during recruitment in an attempt to identify true sentinels. It is for this reason that horses with an outcome of Stable positive are still included in the analysis. For the sake of completeness in this analysis all results have been included and evaluated. While all data available is presented here it is best to view the 2014/2015 and 2015/2016 sentinel surveillance outcomes as they were published.
PCR results are evaluated on a month to month basis
Serological results are evaluated as paired samples taken a maximum of three months apart.
An overview of the permutations of outcomes of monthly sero sentinel surveillance. ns - Not sampled, + Positive, - Negative, s - suspect
Monthly negative outcomes: horizantel lines show minimum expected prevalence level outcome of surveillance
Representative sampling
The goal for the sentinel program is to undertake representative sampling. Below is a map and a table to show for the month that is being reviewed which areas of the surveillance zone had the correct, too few or too many samples taken (seperated by serology and PCR).