Background Nonhuman primates (NHPs) play a significant role in zoonotic spill-overs, serving as either reservoirs, or amplifiers, of multiple neglected tropical diseases, including tick-borne infections. Anaplasma phagocytophilum are obligate intracellular bacteria of the family Anaplasmatacae, transmitted by Ixodid ticks and cause granulocytic anaplasmosis (formerly known as Human Granulocytic Ehrlichiosis (HGE)) in a wide range of wild and domestic mammals and humans too. The aim of this study was to determine whether Anaplasma phagocytophilum was circulating in olive baboons and vervet monkeys in Laikipia County, Kenya. Results Some 146 blood samples collected from olive baboons and 18 from vervet monkeys from Mpala Research Center and Ol jogi Conservancy in Laikipia County were screened for the presence of Anaplasma species using conventional Polymerase Chain Reaction (PCR), and then A. phagocytophilum was confirmed by sequencing using conventional PCR targeting 16S rRNA. This study found an overall prevalence of 18.3% for Anaplasma species. DNA sequences confirmed Anaplasma phagocytophilum in olive baboons for the first time in Kenya. Conclusion This study provides valuable information on the endemicity of A. phagocytophilum bacteria in olive baboons in Kenya. Future research is needed to establish the prevalence and public health implications of zoonotic A. phagocytophilum isolates and the role of nonhuman primates as reservoirs in the region.

BackgroundNonhuman primates (NHPs) occupy an important place in zoonotic spill-overs, serving as either reservoirs or amplifiers of multiple neglected tropical diseases including tick-borne infections. Anaplasmosis is caused by obligate intracellular bacteria of the family Anaplasmatacae. They are transmitted by Ixodid tick species and have a wide host range including wild animals, domestic animals and humans. The aim of this study was to establish the presence of Anaplasma phagocytophilum in Olive baboons and Vervet monkeys in Laikipia County, Kenya.ResultsA total of 164 whole blood samples, collected by USAID Predict II project from Laikipia County, 17 Kenya, were included in the study. These comprised of 146 samples from Olive baboons (Papio anubis) and 18 from Vervet monkeys (Chlorocebus pygerythrus) respectively from Mpala Research Center and Ol jogi Conservancy in Laikipia County. Using conventional Polymerase Chain Reaction (PCR), positive results for A. phagocytophilum in 26 Olive baboons and 4 Vervet monkeys were detected with primer sets EHR16SD/R. However, low sensitivity was observed with the p44 gene. The amplification of DNA template with the primer set p44 (p3709 5/ p4257 23 5) using nested PCR could not be obtained. Our results revealed the presence of A. phagocytophilum in Olive baboons and Vervet monkeys. This study found an overall prevalence of 18.3% for Anaplasma phagocytophilum. A distinct genotype of A. phagocytophilum was detected that was different from the others in the gene bank database.ConclusionThis study provides valuable information on the presence of A. phagocytophilum bacteria in Olive baboons and Vervet monkeys in Kenya. It indicates a need for future research to establish the public health implications of zoonotic A. phagocytophilum isolates and the role of nonhuman primates as reservoirs.