Tick populations and molecular detection of selected tick-borne pathogens in questing ticks from northern and central Tanzania

Abstract

Ticks are vectors and reservoirs of a variety of pathogens including protozoa, bacteria and viruses which cause tick-borne diseases (TBDs) in humans and livestock. TBDs pose serious constraints to the improvement of livestock production in tropical and subtropical regions of the world. Despite their wide distribution, information on the tick and pathogen relationship is scarce in Tanzania. We used nested PCR and sequencing to screen pathogens of public and veterinary health importance in ticks collected by flagging from four districts of Tanzania. In total, 2021 ticks comprising nine species were identified. DNA from ticks was pooled according to tick species, developmental stage, and location, then screened for Babesia bigemina, Babesia bovis, Theileria parva and Coxiella burnetii. Out of 377 pools, 34.7% were positive for at least one pathogen. Theileria parva was the most abundant with a minimum infection rate (MIR) of 2.8%, followed by B. bigemina (MIR = 1.8%) and B. bovis (MIR = 0.8%). Multiple pathogens detection was observed in 7.2% of the tested pools. However, PCR screening of individual tick DNA revealed that only 0.3% of the examined pools had co-infection. DNA of C. burnetii was never detected in any tick DNA pool. The MIR of tick-borne pathogens (TBPs) differed significantly among districts, seasons, tick species, and tick developmental stages. Sequence analysis showed that B. bigemina RAP-1a, B. bovis SBP-4, and T. parva p104 genes were conserved among pathogens in the four districts. Despite the absence of C. burnetii in ticks, considering its pathogenic potential, it is essential to continue monitoring for its possible recurrence in ticks. This information adds to the knowledge of TBPs epidemiology and will contribute to the scientific basis for planning future control strategies.

Composition of the Midgut Microbiota Structure of Haemaphysalis longicornis Tick Parasitizing Tiger and Deer

“…H. longicornis has a wide range of hosts; these hosts mainly are deer, cattle, sheep, brown rabbits, and dogs [ 3 ]. The direct harms of these ticks to hosts include paralysis, anemia, emaciation, and decreased fur quality [ 4 ]. More importantly, they act as vectors for several pathogens that can be transmitted to humans and animals during the blood-sucking process [ 5 ].…”

Current Status and Challenges Associated with Tick-Borne Pathogens and Diseases: Where Do We Stand?

“…TBPs are a concern in tropical and subtropical regions of Africa, and their prevalence varies by geographic location, depending on the tick species present [24]. The study conducted a systematic review and meta-analysis of articles reporting tick abundance, TBP prevalence, and distribution in domestic ruminants across the SADC region.…”