4. WARTHOGS, BUSH PIGS AND SOFT TICKS AS NATURAL RESERVOIRS
African swine fever can lead to high mortalities in domestic pigs while being asymptomatic in the natural suid reservoir hosts (Jia et al., 2017). Wild pigs (warthogs and bush pigs), and soft ticks of the genus Ornithodoros  serve as natural reservoirs in ASFV transmission (Costard et al., 2013). Wild pigs including warthogs and bush pigs may be persistently infected generally developing asymptomatic infections, often referred to as the sylvatic cycle (Kimberling and Teegarden, 1979). Young warthogs may develop a transient viremia to infect new ticks without developing clinical disease, and adult warthogs may be resistant to the pathogenic effects of the virus although the virus can be often extracted from their lymph nodes (Penrith, 2009).Soft ticks from the genus Ornithodoros are responsible for the transmission of ASFV in the environment and acts as a main source of infection (Burrage, 2013). Even though, soft ticks like Ornithodoros moubata and O. erraticus have been reported to be involved in the sylvatic transmission cycle of the virus in Africa and Europe respectively, several other species of Ornithodoros (O. moubata, O. sonrai, O. coriaceusO. turicataO. parkeri , and O. puertoricensis ) have also been confirmed as the biological vectors for transmission of ASF (Frant et al., 2017). Infection from the wild pigs to the domestic population is largely dependent on ticks of the Ornithodoros species than infections through contact between wild and domestic pigs (Costard et al., 2009). Apart from soft ticks, biting flies (Stomoxys spp.) have shown to be capable of transmitting the disease into the swine population (CSFPH, 2019).