Epidemiology and RAPD-PCR typing of thermophilic campylobacters from children under five years and chickens in Morogoro Municipality, Tanzania

Abstract

Background: Campylobacter species are gram negative and flagellated bacteria under the genus Campylobacter, family Campylobacteriaceae. These pathogens cause zoonotic infections among human and animal populations. This study was undertaken between December 2006 and May 2007 to determine prevalence, risk factors and genetic diversity of thermophilic Campylobacter isolates from children less than 5 years and chickens in Morogoro Municipality, Tanzania. Methods: The Skirrow's protocol was used for isolation and identification of Campylobacter from 268 human stool specimens and 419 chicken cloacal swabs. Patient biodata and risk factors associated with human infection were also collected. Genetic diversity of Campylobacter isolates was determined by a RAPD-PCR technique using OPA 11 primer (5′-CAA TCG CCG T-3′). Phylogenetic analysis and band pattern comparison were done by Bionumerics software and visual inspection. Results: Stool samples from 268 children and 419 cloacal swabs from chickens were analyzed. Prevalence of thermophilic Campylobacters in children was 19% with higher isolation frequency (p = 0.046) in males (23.5%) than females (13.8%). Campylobacter jejuni (78.4%) was more isolated (p = 0.000) than C. coli (19.6%) and 2% were unidentified isolates. In chickens, the prevalence was 42.5% with higher isolation rate (p = 0.000) of C. jejuni (87%) than C. coli (13%). Campylobacters were more frequently recovered (p = 0.000) from indigenous/ local chickens (75. 0%) followed by cockerels (52.2%), broilers (50.0%) and lowest in layers (22.7%). Keeping chickens without other domestic animals concurrently (p = 0.000), chicken types (p = 0.000) and flock size (p = 0.007) were risk factors for infection in chickens. One hundred and fifty two (152) thermophillic Campylobacter isolates were genotyped by RAPD-PCR of which 114 were C. jejuni (74 from chickens and 40 humans) and 38 C. coli (28 from chickens and 10 humans). Comparison of Campylobacter isolates from children and chickens revealed high diversity with only 6.1% of C. jejuni and 5.3% of C. coli being 100% genetically similar.

Molecular determination of genetic diversity among Campylobacter jejuni and Campylobacter coli isolated from milk, water, and meat samples using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR)

“…Detection of genotypic relatedness among some C. coli and C. jejuni isolates recovered from aquatic milieu and meat sources confirmed that livestock and poultry are sources of environmental spread of Campylobacter species and these results is in accordance with the report of [ 54 ]. Genetic diversity is one of the different mechanisms that helps pathogens to thrive in unfriendly circumstances within the environment or in the host given them the ability to colonize multiple hosts [ 55 ]. Genomic rearrangement and horizontal gene transfer are among the diverse phenomena that can cause genetic diversity in C. jejuni and C. coli [ 45 ].…”

Campylobacter, a zoonotic pathogen of global importance: Prevalence and risk factors in the fast-evolving chicken meat system of Nairobi, Kenya

“…Few studies found a prevalence lower than 30%. A Ghanaian study found Campylobacter in 22.5% of ceacal samples [37], a Tanzanian study in 42.5% of chickens (various breeds) using cloalcal swabs [12] and an Ethiopian study, in 28.9% of chickens (various breeds) [45]. A study from 1988 found a prevalence of 51.5% in Kenyan broilers [46], whereas a 2018 study found an overall prevalence of 69.5% in Nairobi chickens [28].…”

“…Indeed, studies in Ethiopia and Tanzania have identified marked differences in prevalence between broiler and indigenous chicken flocks, with conflicting results. Two studies in Tanzania found a higher Campylobacter prevalence in indigenous chickens (76.49% and 75%) compared to broilers (26.4% and 50%) [47,12]. Another Tanzanian study found no significant difference between broilers and indigenous chickens, but rather a higher prevalence in local chickens from rural areas compared to those in urban areas [48], while an Ethiopian study found significantly higher Campylobacter isolation rates in animals (chicken, sheep, cattle and pigs) in urban areas (56.7%) compared to rural areas (26.7%)[49].…”

“…A Campylobacter isolation rate of 8% was reported in all-age diarrheic patients in Ethiopia [10], compared to 12% (higher than for Salmonella and Shigella ) in Kenya [11]. A Campylobacter prevalence of 19% was reported in children under 5 from Morogoro, Tanzania [12], whereas a study in Western Kenya health centers isolated Campylobacter spp. from 42% of diarrheic children under 5 [13].…”

Prevalence, Risk Factors, and Antimicrobial Resistance Profiles of Thermophilic Campylobacter Species in Humans and Animals in Sub-Saharan Africa: A Systematic Review

“…Of the 33 articles, only four reported on risk factors of campylobacteriosis in humans. In Tanzania, Campylobacter infections were associated with sex, young age, poultry meat consumption, and eating of salads [26,38]. In Ethiopia, human campylobacteriosis was significantly associated with nonuse of latrines, water source, drinking unboiled water, bottle feeding, nutritional status, and exposure to domestic animals including cats, dogs, poultry, and pigeons [25].…”