BackgroundOnly limited information is currently available on the prevalence of vector borne and zoonotic pathogens in dogs and ticks in Nigeria. The aim of this study was to use molecular techniques to detect and characterize vector borne pathogens in dogs and ticks from Nigeria.Methodology/Principal FindingsBlood samples and ticks (Rhipicephalus sanguineus, Rhipicephalus turanicus and Heamaphysalis leachi) collected from 181 dogs from Nigeria were molecularly screened for human and animal vector-borne pathogens by PCR and sequencing. DNA of Hepatozoon canis (41.4%), Ehrlichia canis (12.7%), Rickettsia spp. (8.8%), Babesia rossi (6.6%), Anaplasma platys (6.6%), Babesia vogeli (0.6%) and Theileria sp. (0.6%) was detected in the blood samples. DNA of E. canis (23.7%), H. canis (21.1%), Rickettsia spp. (10.5%), Candidatus Neoehrlichia mikurensis (5.3%) and A. platys (1.9%) was detected in 258 ticks collected from 42 of the 181 dogs. Co- infections with two pathogens were present in 37% of the dogs examined and one dog was co-infected with 3 pathogens. DNA of Rickettsia conorii israelensis was detected in one dog and Rhipicephalus sanguineus tick. DNA of another human pathogen, Candidatus N. mikurensis was detected in Rhipicephalus sanguineus and Heamaphysalis leachi ticks, and is the first description of Candidatus N. mikurensis in Africa. The Theileria sp. DNA detected in a local dog in this study had 98% sequence identity to Theileria ovis from sheep.Conclusions/SignificanceThe results of this study indicate that human and animal pathogens are abundant in dogs and their ticks in Nigeria and portray the potential high risk of human exposure to infection with these agents.

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Previous and ongoing studies have incriminated bats as reservoirs of several emerging and re-emerging zoonoses. Most of these studies, however, have focused on viral agents and neglected important bacterial pathogens. To date, there has been no report investigating the prevalence of Bartonella spp. in bats and bat flies from Nigeria, despite the fact that bats are used as food and for cultural ritual purposes by some ethnic groups in Nigeria. To elucidate the role of bats as reservoirs of bartonellae, we screened by molecular methods 148 bats and 34 bat flies, Diptera:Hippoboscoidea:Nycteribiidae (Cyclopodia greeffi) from Nigeria for Bartonella spp. Overall, Bartonella spp. DNA was detected in 76 out of 148 (51.4%) bat blood samples tested and 10 out of 24 (41.7%) bat flies tested by qPCR targeting the 16S-23S internal transcribed spacer (ITS) locus. Bartonella was isolated from 23 of 148 (15.5%) bat blood samples, and the isolates were genetically characterized. Prevalence of Bartonella spp. culture-positive samples ranged from 0% to 45.5% among five bat species. Micropterus spp. bats had a significantly higher relative risk of 3.45 for being culture positive compared to Eidolon helvum, Epomophorus spp., Rhinolophus spp., and Chaerephon nigeriae. Bartonella spp. detected in this study fall into three distinct clusters along with other Bartonella spp. isolated from bats and bat flies from Kenya and Ghana, respectively. The isolation of Bartonella spp. in 10.0-45.5% of four out of five bat species screened in this study indicates a widespread infection in bat population in Nigeria. Further investigation is warranted to determine the role of these bacteria as a cause of human and animal diseases in Nigeria.

BackgroundBartonellae are fastidious bacteria causing persistent bacteremia in humans and a wide variety of animals. In recent years there is an increasing interest in mammalian bartonelloses in general and in rodent bartonelloses in particular. To date, no studies investigating the presence of Bartonella spp. in rodents and ectoparasites from Nigeria were carried out.Methodology/Principal FindingsThe aim of the current study was to investigate the presence of Bartonella spp. in commensal rodents and their ectoparasites in Nigeria. We report, for the first time, the molecular detection of Bartonella in 26% (46/177) of commensal rodents (Rattus rattus, R. norvegicus and Cricetomys gambianus) and 28% (9/32) of ectoparasite pools (Xenopsylla cheopis, Haemolaelaps spp., Ctenophthalmus spp., Hemimerus talpoides, and Rhipicephalus sanguineus) from Nigeria. Sequence analysis of the citrate synthase gene (gltA) revealed diversity of Bartonella spp. and genotypes in Nigerian rodents and their ectoparasites. Bartonella spp. identical or closely related to Bartonella elizabethae, Bartonella tribocorum and Bartonella grahamii were detected.Conclusions/SignificanceHigh prevalence of infection with Bartonella spp. was detected in commensal rodents and ectoparasites from Nigeria. The Bartonella spp. identified were previously associated with human diseases highlighting their importance to public health. Further studies need to be conducted to determine whether the identified Bartonella species could be responsible for human cases of febrile illness in Nigeria.

The cattle tick Rhipicephalus (Boophilus) microplus was first reported in West Africa in Ivory Coast, in 2007. Since then it has made an aggressive eastward advancement having been reported in four other West African countries: Mali, Burkina Faso, Togo and Benin. We herein report the first molecular identification of this tick species in Nigeria, West Africa, and highlight the threat it poses to livestock health. A nation-wide tick survey was conducted in 12 out of 36 states across the various agro ecological zones of Nigeria over a 1 year period (April 2014-March 2015). In total 1498 ticks belonging to three genera collected from cattle were morphologically identified. Overall, Amblyomma species constituted the highest percentage of sampled ticks, 50.2% (752/1498), followed by Rhipicephalus (including the subgenus Boophilus) species, 29.4% (440/1498) and Hyalomma species, 20.4% (306/1498). The presence of Rh. (B.) microplus was identified morphologically from four out of the 12 states. This finding was confirmed for the first time in Nigeria using a molecular method targeting the ITS-2 region of the ticks in three of the 12 states. This study ascertained the presence of Rh. (B.) microplus in Nigeria in addition to a broad variety of cattle tick species, most of which are of veterinary importance. The implication of this finding is that there may be additional economic burden to livestock farmers due to increased cost of tick control occasioned by the acaricide resistance by this tick species widely reported from different climes. Additionally, there may be a potential upsurge in incidence of hemoparasitic infections in cattle leading to increased morbidity, cost of treatment and mortalities.