ABSTRACT
Tick-borne relapsing fever (TBRF) is a bacterial disease caused by Borrelia species
which is transmitted to humans by infected ticks. The disease occurs worldwide. In West
Africa, geographical distribution of Borrelia is classically limited to the Sahel and
Saharan regions; there are no documented cases of the disease in Nigeria. This study is a
response to a report of suspected TBRF in Borno state. The aim is to determine
demographic features and risk factors associated with suspected cases of TBRF in
northern Borno State Nigeria. A cross-sectional study was carried out in four community
health centres and two referral hospitals using an interviewer administered questionnaires
to obtain demographic information. One hundred samples of tick were collected from
resting places in livestock markets, hemolymph smear were stained with Giemsa stain to investigate for Borrelia. Questionnaires were analyzed using Epi info version 3.5.1,
Winepiscope soft ware and excel spread sheet. The Ages of respondents ranged from 3-
70 years, both males and females had symptoms of TBRF. Their primary occupation was
farming and trading. Keeping of animals was a significant (OR = 6.56, 95 % CI 1.73-
24.88) risk factor for tick infestation, while keeping of animals and sleeping outside at
night (OR = 4.88, 95 % CI 1.09-21.88 and OR= 3.91, 95 % CI 1.49-10.30) were
significant for tick bite. None of the 100 hemolymph smear revealed Borrelia spirochete
at X100. All the four communities were infested widely with ticks. Respondents of both
sexes and age groups studied were engaged in occupation that exposes them to tick bite
and TBRF. The state should conduct public health campaigns on preventing tick bite and
establish tick-borne borreliosis surveillance mechanism.
Key Words: Ornithodoros, Borrelia, risk factor, Borno State, Nigeria.