Geospatial and modelling analyses reveal diverse tick and tick-associated microbes in the East African Community.

Background: The continuous geographic expansion of ticks and the emergence of tick-borne diseases have raised tremendous global public health concerns, particularly in the East African Community (EAC). This study aimed to investigate the distribution of ticks and tick-associated microbes and to predict the potential extension of dominant tick species in the EAC.

Methods: Data were collected from literature reviews and related websites and analyzed using ArcGIS to generate maps showing the geographical distribution of ticks and associated microbes. Meta-analyses were conducted to estimate the positive rates of microbes. Ecological niche modelling was used to project the potential expansion of predominant tick species.

Results: A total of 138 tick species were recorded in the seven EAC countries, including five genera of the Argasidae family, eight of the Ixodidae family, and monospecific Nuttalliellidae. Overall, 64 tick-associated microbes, including 22 viruses, 26 bacteria, and 16 protists, were identified, of which 43 (11 viruses, 21 bacteria, and 11 protists) were pathogenic to humans or animals. Among them, 5 (2 viruses and 3 bacteria) have been reported in humans, while 10 pathogens (1 virus, 4 bacteria, and 5 protists) have been reported in animals. The predictive model identified suitable habitats for four dominant tick species, with certain species flourishing under ideal conditions, such as elevation, temperature, and vegetation. Our study revealed that ticks might affect broader areas where they have never been previously reported.

Conclusions: Ticks are widely prevalent in the EAC, and some ticks harbor a variety of microbial agents that can have significant pathogenetic implications for human and animal health. Therefore, EAC authorities and medical personnel should acknowledge the potential threat posed by ticks and tick-associated pathogens to the well-being of people and animals. Surveillance and etiological diagnosis should be enhanced to control ticks and prevent tick-borne infections.