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Background Brucellosis is a bacterial zoonosis of public health and economic importance worldwide. It affects a number of domestic animals, wild animals and humans. Human brucellosis originates from either livestock or wildlife. The species of Brucella circulating in wild animals in Tanzania is largely unknown due to insufficient surveillance. This study was carried out to identify Brucella species found in selected wildlife hosts in the Serengeti ecosystem. Methodology The study used a total of 189 archived samples that were obtained from cross-sectional studies previously conducted between 2000 and 2017 in the Serengeti ecosystem in Tanzania. Whole blood, serum and amniotic fluid collected from buffalos, lions, wildebeest, impala, zebra and hyena were available for DNA extraction. Multiplex polymerase chain reaction for B. abortus, B. melitensis, B. ovis and B. suis (AMOS PCR) and quantitative real-time PCR (qPCR) targeting the bcsp31 and IS711 genes for Brucella genus detection and the IS711 targets alkB for B. abortus and BMEI1162 for B. melitensis were used to detect Brucella strains. Results Out of the 189 samples tested, 12 (6.35 %) and 22 (11.6 %) were positive to AMOS-PCR and qPCR, respectively. Most of the positive samples were from lions (52.6 %) and buffaloes (19.6 %). Other animals that were positive included: wildebeest (13.6 %), impala (13.6 %), zebra (4.5 %) and hyena (4.5 %). Out of 22 positive samples, 16 (66.7 %) were identified as B. abortus and the other six samples did not amplify for neither B. abortus nor B. melitensis. Conclusions The detection of Brucella DNA in archived wild animal samples shows testing potential of samples collected from this population. The zoonotic species B. abortus and B. melitensis detected in wild animals have previously been reported in livestock and humans in the region. The findings suggest that, due to the contact network, some of the identified wild animal hosts in this study could be reservoirs for infections in domestic animals and humans within the Serengeti ecosystem while others are likely dead-end hosts. One Health control strategies and continuous surveillance programs in other wildlife reserved areas should be implemented to help predicting transmission in livestock and humans in the region.

BackgroundBrucellosis is a bacterial zoonosis of public health and economic importance world-wide. It affects a number of domestic animals, wildlife and humans. This study was carried out to determine circulating Brucella species in wildlife in Serengeti ecosystem using molecular techniques.MethodologyA total of 189 samples including EDTA blood, serum and amniotic fluid from buffalos, lions, wildebeest, impala, zebra and hyena that were collected in relation to different cross-sectional studies conducted in the Serengeti ecosystem in Tanzania were used. Multiplex polymerase chain reaction AMOS-PCR and quantitative Real-Time PCR (qPCR) targeting the genus specific surface protein bcsp31 gene and the insertion sequence IS711 element downstream of the alkB gene for B. abortus and BMEI1162 gene for B. melitensis were employed on the samples.ResultsResults indicated that out of 189 samples examined, 12 (6.4%) and 22 (11.6%) contained Brucella DNA as detected by AMOS-PCR and qPCR, respectively. Most of the positive samples were from lions (52.6%) and buffaloes (19.6%). Other animals that were positive included wildebeest, impala, zebra and hyena. Out of 22 positive samples, 16 (66.7%) were identified as B. abortus and the rest were B. melitensis.ConclusionDetection of zoonotic Brucella species in wildlife suggests that livestock and humans at the interface areas where there is high interaction are at risk of acquiring the infection. Therefore, public education to interrupt risky transmission practices is needed. The findings also shed light on the transmission dynamics around interface areas and the role of wildlife in transmission and maintenance of Brucella infection in the region.

Treponema pallidum subsp. pertenue (TPE) is the causative agent of yaws. The disease was subject to global eradication efforts in the mid 20th century but reemerged in West Africa, Southern Asia, and the Pacific region. Despite its importance for eradication, detailed data on possible nonhuman disease reservoirs are missing. A number of African nonhuman primates (NHPs) have been reported to show skin ulcerations suggestive of treponemal infection in humans. Furthermore antibodies against Treponema pallidum (TP) have been repeatedly detected in wild NHP populations. While genetic studies confirmed that NHPs are infected with TP strains, subspecies identification was only possible once for a strain isolated in 1966, pinpointing the involvement of TPE. We therefore collected a number of recently isolated simian TP strains and determined eight whole genome sequences using hybridization capture or long-range PCR combined with next-generation sequencing. These new genomes were compared with those of known human TP isolates. Our results show that naturally occurring simian TP strains circulating in three African NHP species all cluster with human TPE strains and show the same genomic structure as human TPE strains. These data indicate that humans are not the exclusive host for the yaws bacterium and that a One Health approach is required to achieve sustainable eradication of human yaws.

Faecal samples from 168 goats belonging to eight urban establishments and representing three commonly encountered management systems were screened for Campylobacter spp. Goats which were kept isolated from other farm animals with or without good management systems were negative for Campylobacter spp., although in one of these units 2 9 chickens were consistently positive for C. coli. However, 3 out of 20 goats confined in an enclosed area but in contact with C. coli positive pigs ( 3 10 ) and chickens ( 2 8 ) were infected with C. coli. Furthermore, 24 milk samples tested on three different occasions were negative. This study indicates that goats are not natural hosts of C. coli or C. jejuni and that pigs and poultry act as a source of infection.

Four different infective doses (log 10 1.00, 3.00, 5.00 and 7.00 colony-forming units (CFU) ml −1 of a suspension of Campylobacter jejuni were assessed for their ability to colonize forr groups of 1-day-old chicks. The infective potential of experimentally infected peat moss litter for the 3-day-old chicks was also investigated. Using cloacal swabs as the indicator, C. jejuni was detected in orally challenged chicks within 24 h of exposure to oral doses of log 10 5.00 and 7.00 CFU per chick. Chicks challenged with lower doses, i.e. log 10 3.00 and 1.00 CFU, became positive after 3 days and 21 days, respectively. Non-infected chicks introduced into a contaminated environment on Days 7 and 14 of the experiment became positive within 24–48 h of contact. Chicks reared on contaminated litter acquired the infection and started to shed the organism in their droppings after 5 days. No important gross pathological lesions were observed at necropsy. Birds of the control group remained free of C. jejuni throughout the rearing period (5–6 weeks).