Anaplasma Species in South Africa
The “Anaplasma species in South Africa” programme's research includes investigations into the presence and genetic diversity of Anaplasma marginale in South Africa and the molecular characterization of vaccine candidates from these strains. The group aims to generate genome sequences of a number of Anaplasma species in order to identify genes and proteins that are unique to A. marginale for the development of more specific molecular and serological tests. In 2018, in vitro cultures of South African A. marginale strains were established in embryonic tick cell lines in collaboration with researchers at the ARC-OVI, but these cultures were stopped when the COVID-19 lockdowns were implemented. The group has subsequently been investigating methods of obtaining whole genome sequences of Anaplasma species directly from carrier animals, without the need for initiation of cultures. A targeted 16S microbiome approach was used to identify novel Anaplasma species in African wildlife, and research is underway to obtain genome sequences from these novel organisms.
The programme is led by Dr Collins, who is also working in collaboration with Dr Marinda Oosthuizen on the characterization of A. marginale and A. centrale in cattle and buffalo, and on the identification of zoonotic tick-borne pathogens.
Dr Collins’ research career has mainly focused on molecular studies of haemoparasites of veterinary importance. She was one of the principal researchers involved in the sequencing of the 1.5 Mb Ehrlichia ruminantium genome, which was the first bacterial genome to be completed in Africa, and was a major achievement for all the researchers involved.
She has also been involved in the development of molecular diagnostic tests for Theileria parva, Theileria equi and Babesia caballi and in the molecular characterization of these parasites. Her research revealed the existence of genetic and serological heterogeneity in T. equi and B. caballi parasites in South Africa, which explains the failure of many molecular and serological tests to detect these parasites in field samples in this country. Other projects include the identification T. parva carrier cattle in the Mnisi Community Area and the characterization of T. parva parasites identified, as well as studying the time-course of tick-borne haemoparasite infection in calves at the wildlife-livestock interface in the Mnisi Community.