Ticks (Acari: Ixodidae) and tick-borne diseases in Cameroon: Current understanding and future directions for more comprehensive surveillance

Abstract

Despite the high burden of human and animal infectious diseases in Cameroon, implementing integrative approaches to managing and controlling arthropods and their pathogens remains challenging. Surveillance should be designed to detect diseases and provide relevant field-based data for developing and implementing effective control measures to prevent outbreaks before significant public and animal health consequences can occur. Nowadays, ticks are considered the primary vectors of animal diseases in the world, and the second vector of human diseases after mosquitoes. Knowledge of their biodiversity and distribution in any given area is a crucial step towards a better implementation of control strategies. The infections transmitted by ticks remain poorly known or underestimated in Cameroon. Despite the existence of several studies on ticks and associated pathogens, no single review to date summarises all the data available in this field in Cameroon. Following a comprehensive literature search, an inventory of the diversity and distribution of ticks, as well as the different tick-borne diseases (viral, bacteria and protozoa) found in Cameroon was prepared. To date, about 71 species, comprising ten Amblyomma species., eight Hyalomma spp., 26 Rhipicephalus spp., 11 Haemaphysalis spp., seven Ixodes spp., five Aponomma spp. (currently the Bothriocroton species), one Dermacentor, and four soft tick species of minimal or unknown medical and veterinary importance, namely Argas persicus, A. arboreus, Carios vespertilionis, and Ogadenus brumpti have been collected in Cameroon. Many zoonotic tick-borne diseases, such as babesiosis, theileriosis, anaplasmosis, ehrlichiosis, rickettsioses, and Q fever have been reported in the country. Knowledge about tick species and their distribution will aid in designing integrated vector management programs to monitor tick-borne diseases in Cameroon.

Keywords: Cameroon; Distribution; Tick-borne diseases; Ticks; Zoonoses.

Fig. 1

Maps showing the distribution of tick species by agro-ecological zone in Cameroon. A = Ixodidae (hard ticks), B = Argasidae (soft ticks).