6.5 Correlation between the epidemiological cycles of ASF
The ASF outbreaks in several countries in Europe in the year 2014-2017,
seems to follow the common domestic epidemiological cycle, i.e. the
infection circulates among small pig farms, affecting few commercial
farms, and frequently spills over to wild boars (EFSA, 2014).From these
data, a previously undescribed epidemiologic cycle of ASF became
evident: a cycle that focuses on the wild boar population and its
habitat as a virus reservoir and led to the addition of a new cycle
known as ‘wild boar-habitat cycle’ (Chenais et al., 2018; FAO, 2020b).
This cycle is characterized by (i) direct transmission between infected
pigs/wild-boar and susceptible wild boar; and (ii) indirect transmission
through ASF contaminated carcasses in the habitat and the possible
subsequent intraspecies scavenging, and thus, the cycle continues
(Probst et al., 2017).
Possibility of future outbreaks or establishment of endemism of ASF in
India will depend upon the maintenance of epidemiological cycles of ASF
as well as distribution of reservoirs and susceptible hosts. We have
analysed the four established epidemiological cycles of ASF from Indian
perspective to describe the risk associated with each cycle (Figure 2).