RESUMO
Rift Valley fever (RVF) is a complex emerging arboviral hemorrhagic disease that causes significant illness in animals and humans. Camel trade across the land borders between Nigeria and the Niger Republic occurs frequently and poses a significant risk for RVF transmission to pastoralists and traders. We carried a cross-sectional study between November 2016 and April 2017 in two northern States (Katsina and Jigawa) known for camel trade in Nigeria to investigate the seroprevalence and potential risk factors for RVFV occurrence. We collected 720 sera and administered questionnaire to pastoralists. We used the competitive enzyme-linked immunosorbent assay (c-ELISA) to determine the previous exposure to RVFV infection. We retrieved environmental information from public data sources that might explain RVFV seropositivity at the LGA level. To asses potential risk factors,we categorized LGAs with RVFV as "1" and those without a case" 0". We fitted a logistic model to the data and estimated odds ratios and 95% confidence intervals. An overall 19.9% prevalence was reported among camel herd-the highest seropositivity (33.3%) was recorded in SuleTankarkar LGA. In the multivariable model, only rain-fed croplands was significantly associated with RVFV antibodies occurrence p = 0.048 (OR = 0.87, 95% CI: 0.76-0.99). Only a minority of the respondents, 19.3% (n = 17/88), knew that RVF is zoonotic. Separation of healthy animals from the infected animals was carried out by 53.4% (47/88) pastoralists while 59.1% (52/88) pastoralists still use ethnoveterinary practices to control or mitigate disease outbreaks. Our study demonstrates the presence of RVFV antibodies among camel in Nigeria and the associated risk factors. These findings highlight the need for enhancing surveillance and control efforts and the public health education of camel pastoralists. Further investigation to unravel the zoonotic transmission potential to pastoralists and other animal species is pertinent.
RESUMO
Prevalence and distribution of Shiga toxin-producing Escherichia coli (STEC) serogroups from the faecal samples of cattle and camels slaughter in Maiduguri abattoir and their antibiotic resistance profile of the isolates were determined. The highest prevalence (24%) was recorded in the month of September and more STEC isolates came from cattle than the camels. There was significant (P < 0.05) seasonal trend in the prevalence of STEC among cattle and camel with more cases recorded during the wet season. Although, the study did not demonstrate significant influence of sex from the various sources. The serogroups recorded in this study were O157, O26, O91, O103 and O111. There was no significant difference (P < 0.05) between the detection rates of serogroups. The serogroup O26 was significantly (P < 0.05) the most observed serogroup in both camels and cattle. None of the STEC isolates tested positive for the O45 serogroup. PCR assays shows that 50 (63.3%) of the 86 STEC isolates carried the stx2 gene, 34 (43%) possessed the stx1 gene, and 14 (16.3%) carried both stx1 and stx2 genes. Other genes detected include eae and ehlyA. The antimicrobial resistance among the STEC O157 and non-O157 isolates from cattle and camels in Maiduguri abattoir were very high and the STEC isolates were resistant to at least one or more of the antimicrobial agents tested. There was also multidrug resistance with the most frequent occurring patterns been ampicillin/nalidixic acid and tetracycline/trimethoprim. However, all the 79 isolates were sensitive to chloramphenicol, ceftazidime and ceftriaxone; therefore, these drugs could be drugs of choice in the treatment of STEC infections.