High Prevalence and New Genotype of Coxiella burnetii in Ticks Infesting Camels in Somalia

Abstract

<i>Coxiella burnetii</i> is the causative agent of Q fever. It can infect animals, humans, and birds, as well as ticks, and it has a worldwide geographical distribution. To better understand the epidemiology of <i>C. burnetii</i> in Somalia, ticks infesting camels were collected from five different regions, including Bari, Nugaal, Mudug, Sool, and Sanaag, between January and March 2018. Collected ticks were tested for <i>C. burnetii</i> and <i>Coxiella</i>-like endosymbiont DNA by using IS1111, <i>icd</i>, and <i>Com1</i>-target PCR assays. Moreover, sequencing of the 16S-rRNA was conducted. Molecular characterization and typing were done by <i>adaA</i>-gene analysis and plasmid-type identification. Further typing was carried out by 14-marker Multi-Locus Variable-Number Tandem Repeats (MLVA/VNTR) analysis. The investigated ticks (<i>n</i> = 237) were identified as <i>Hyalomma</i> spp. (<i>n</i> = 227, 95.8%), <i>Amblyomma</i> spp. (<i>n</i> = 8, 3.4%), and <i>Ripicephalus</i> spp. (<i>n</i> = 2, 0.8%), and 59.1% (140/237) of them were positive for <i>Coxiella</i> spp. While Sanger sequencing and plasmid-type identification revealed a <i>C. burnetii</i> that harbours the QpRS-plasmid, MLVA/VNTR genotyping showed a new genotype which was initially named D21. In conclusion, this is the first report of <i>C. burnetii</i> in ticks in Somalia. The findings denote the possibility that <i>C. burnetii</i> is endemic in Somalia. Further epidemiological studies investigating samples from humans, animals, and ticks within the context of "One Health" are warranted.