Abstract:
The Amblyomma genus is represented on the African continent by 24 species, out of which 17 are known to occur
in different ecological niches of southern Africa. Amblyomma, known for their aggressive hunting behaviour and
aptitude as pathogen vectors, are of main concern to travellers, mainly in rural and conservation areas of Africa.
In this study, we highlight the overlapping distribution of Amblyomma eburneum and Amblyomma variegatum
found on African buffaloes (Syncerus caffer) at Coutada 11, Central Mozambique. In total, 1,039 Amblyomma ticks
were collected and morphologically identified using taxonomic keys, and genomic DNA was extracted. They
were subjected to reverse line blotting for pathogen identification followed by molecular analysis (COI
sequencing) of both tick species. Pathogens such as Ehrlichia ruminantium, Anaplasma centrale, Theileria sp.,
Babesia sp. and Rickettsia africae were detected, of which R. africae is zoonotic. Ehrlichia ruminantium, R. africae,
Theileria mutans and Theileria velifera are well-established pathogens transmitted by Amblyomma ticks; however,
Anaplasma spp. and Babesia spp. are not, suggesting residual parasite DNA in the bloodmeal. Little is mentioned
in the literature about A. eburneum, including its role as a vector and reservoir for pathogens. In Mozambique
A. eburneum is currently restricted to wildlife but the spread of the tick may be observed given the climate change
that is occurring. The infection rates for the pathogens in both Amblyomma tick species were lower than expected,
but this may be due to the low host density in the forest niche and the innate immunity of these hosts. With the
propensity of ticks of the Amblyomma genus to form parapatric distributions, the mechanisms that allows for the
overlapping distribution of these two Amblyomma species while maintaining tick species identity is of great
interest.
