Ticks and Rickettsiae Associated with Wild Animals Sold in Bush Meat Markets in Cameroon

Abstract

Ticks are obligate blood-sucking parasites of wild animals and transmit many zoonotic microorganisms that can spread to domesticated animals and then to humans. In Cameroon, little is known about tick diversity among wildlife, especially for animals which are hunted for human consumption. Therefore, this survey was undertaken to investigate tick and Rickettsia species diversity parasitizing the wild animals sold in bush meat markets in Cameroon. In total, 686 ticks were collected and identified to the species level based on morphology, and some were genetically analyzed using the 16S rRNA gene. Eighteen tick species belonging to five genera were identified: Amblyomma spp. (Amblyomma compressum, Amblyomma flavomaculatum, and Amblyomma variegatum), Haemaphysalis spp. (Haemaphysalis camicasi, Haemaphysalis houyi, Haemaphysalis leachi, and Haemaphysalis parmata), Hyalomma spp. (Hyalomma nitidum, Hyalomma rufipes, and Hyalomma truncatum), Ixodes spp. (Ixodes rasus and Ixodes moreli), and Rhipicephalus spp. (Rhipicephalus guilhoni, Rhipicephalus moucheti, Rhipicephalus muhsamae, Rhipicephalus microplus, Rhipicephalus camicasi, and Rhipicephalus linnaei). In terms of Rickettsia important for public health, two Rickettsia spp., namely Rickettsia aeschlimannii and Rickettsia africae, were detected in Hyalomma spp. and Amblyomma spp., respectively. Distinct tick–pathogen patterns were present for divergent sequences of R. africae associated with exclusively A. variegatum vectors (type strain) versus vectors comprising A. compressum, A. flavomaculatum, and A. variegatum. This suggests possible effects of vector species population dynamics on pathogen population circulation dynamics. Furthermore, Candidatus Rickettsia africaustralis was detected for the first time in Cameroon in I. rasus. This study highlights the high diversity of ticks among wildlife sold in bush meat markets in Cameroon.

Molecular Analysis of Tick-Borne Bacterial Pathogens from Ticks Infesting Animal Hosts in Kyrgyzstan, 2021

“…Tick species are typically identified based on their morphological characteristics, which require well-trained technicians for accurate identification [ 16 ]. This process becomes more challenging when ticks are engorged with blood or are physically damaged [ 17 ]. To address this challenge, various molecular identification techniques have been employed using mitochondrial (cytochrome oxidase subunit 1; CO1 [ 18 ], 12S and 16S ribosomal RNA [ 19 ]) and nuclear markers (internal transcribed spacer 1 and 2, 18S, 28S [ 19 , 20 ]).…”

Morphological and Molecular Identification of Hard Ticks in Hainan Island, China

“…This involves the use of specialized keys or taxonomic guides that provide detailed descriptions and illustrations of different tick species, as well as their geographic distribution, host preferences and pathogen transmission potential [ 13 ]. However, morphological identification is insufficient in separating between related species complexes, particularly when the specimens are at immature stages, physically damaged or engorged [ 14 ]. Therefore, molecular techniques such as sequencing of the cytochrome oxidase subunit 1 ( cox1 ) gene and 16S ribosomal RNA ( 16S rRNA) gene can be used to characterize tick species [ 15 , 16 ].…”