Abstract:
Prevalence of thermophilic Campylobacter infections in
humans, chickens and crows was determined in a cross-sectional
study that was carried out in urban and rural areas of
Morogoro region, Tanzania during the period of January 2003
to December 2004. A total of 632 human stool samples, 536
cloacal swabs from local and broiler chickens and 22 intestinal
contents from crows were screened for presence of thermophilic
campylobacters using Skirrow’s protocol. Representative
Campylobacter jejuni isolates from human and chicken
samples were also analysed by polymerase chain reaction
(PCR) as a definitive identification method. The overall prevalence
of thermophilic campylobacters was 9.3% (95% CI:
7.2–11.9), 69.8% (95% CI: 65.7–73.6) and 72.7% (95% CI:
49.8–89.3) in humans, chickens and crows respectively. In
humans, 59 thermophilic campylobacters were isolated of
which 96.6% were C. jejuni and 3.4% Campylobacter coli.
There was a significantly (P < 0.001) higher prevalence in
young individuals (16%) than in adults (7%). Of 341 isolates
from chickens, 91.2% were C. jejuni and 8.8% were C. coli.
A significantly (P < 0.05) higher infection rate was observed
in rural local chicken (76%) than in broilers (60%). In crows,
of 16 isolates, 93.8% were C. jejuni and 6.2% were C. coli.
Definitive identification of C. jejuni by PCR revealed positive
results in 74.1% of 243 analysed isolates. Findings in this study
indicate high prevalence of thermophilic campylobacters in
humans, chickens and crows in Morogoro, and a higher
infection rate of C. jejuni than that of C. coli in different animal
species. Age of humans and location of chickens were identified
as risk factors for thermophilic Campylobacter infections.
Positive isolates to biochemical tests that indicated negative
results on PCR indicates the additional value of PCR for
definitive diagnosis of C. jejuni.
