Presence and Persistence of Amblyomma Hebraeum Augments the Burden of Heartwater in the Southern District of Botswana

Abstract BACKGROUNDHeartwater is a tick-borne, haemoparasitic disease that has the potential to limit the growth of agro-businesses in Botswana. This threat to national food security is attributed to low production and mortality of livestock in subsistence farming of small stock than in commercial farms. This study gives a view of the epidemiological burden of heartwater in Botswana. METHODSFeeding ticks on livestock kept in four Southern sub-districts of Botswana were identified through morphological and molecular analysis. Farmers were interviewed on the management of the heartwater burden within their respective sub-districts. Veterinary clinical case reports were collected to assess the frequency of cases across the Southern District of Botswana. RESULTSOutcomes of the study revealed; a wide distribution of Amblyomma hebraeum in all four studied sub-districts, gradual annual increase in heartwater cases in Moshupa sub-district and indication of increased impact on indigenous caprine species despite the effort to control vectors by 63% of interviewed farmers. CONCLUSIONAmblyomma hebraeum, the principal vector of Ehrlichia ruminantium in Southern Africa is widely distributed in the Southern District of Botswana and thus poses a challenge to livestock productivity in this district and, perhaps, elsewhere in the country where the tick infests livestock. There is therefore a need to re-examine the existing tick control interventions with an intention to reduce the heartwater disease burden particularly in sheep and goats.