Widespread Treponema pallidum Infection in Nonhuman Primates, Tanzania.

We investigated Treponema pallidum infection in 8 nonhuman primate species (289 animals) in Tanzania during 2015-2017. We used a serologic treponemal test to detect antibodies against the bacterium. Infection was further confirmed from tissue samples of skin-ulcerated animals by 3 independent PCRs (polA, tp47, and TP_0619). Our findings indicate that T. pallidum infection is geographically widespread in Tanzania and occurs in several species (olive baboons, yellow baboons, vervet monkeys, and blue monkeys). We found the bacterium at 11 of 14 investigated geographic locations. Anogenital ulceration was the most common clinical manifestation; orofacial lesions also were observed. Molecular data show that nonhuman primates in Tanzania are most likely infected with T. pallidum subsp. pertenue-like strains, which could have implications for human yaws eradication.

SCREENING FOR BOVINE TUBERCULOSIS IN AFRICAN BUFFALO (SYNCERUS CAFFER) IN NGORONGORO CONSERVATION AREA, NORTHERN TANZANIA: IMPLICATIONS FOR PUBLIC HEALTH.

In the Ngorongoro Conservation Area (NCA), Tanzania, where wildlife and livestock interaction is intense, greater potential for intra- and interspecies disease transmission is expected. We assessed the prevalence of bovine tuberculosis in African buffalo (Syncerus caffer) residing on the valley floor of the crater in the NCA. Apparently healthy animals were randomly selected from herds in nine sites of the Ngorongoro Crater. Syncerus caffer buffalo herds were located using very high-frequency radio-aided rangers positioned in various observation points around the crater in the NCA. A total of 102 African buffalo from 16 herds were immobilized from the ground using a cocktail of 4-10 mg etorphine hydrochloride (M99) and 60-150 mg azaperone tartrate. The M99 was reversed using 10-25 mg diprenorphine hydrochloride depending on age of animals. An interferon gamma assay was performed on harvested plasma samples using sandwich enzyme linked immunosorbent assay. Of the 102 animals sampled, two (2%) African buffalo tested positive for bovine tuberculosis. These results corroborate those of the skin test done recently in cattle in the NCA. The presence of bovine tuberculosis in livestock and wildlife suggested the possibility of cross-species transmission of the disease, indicating the need for appropriate intervention measures.

Potential use of mobile phones in improving animal health service delivery in underserved rural areas: experience from Kilosa and Gairo districts in Tanzania.

BACKGROUND: Sub-optimal performance of the animal health delivery system in rural areas is common in developing countries including Tanzania. However, penetration of mobile phones and availability of good road network and public transport systems offer opportunities for improving the access of rural communities to diagnostic and advisory services from facilities and expertise located in urban areas. A questionnaire survey on possession and use of mobile phones by pastoral and agro-pastoral communities in Kilosa and Gairo districts was carried out between November and December 2015. A total number of 138 livestock keepers from three villages of Chakwale (54), Mvumi (41) and Parakuyo (43) participated in the study. An e-based system was designed and tested to link rural communities with urban diagnostic facilities. RESULTS: It was observed that the average number of phones possessed by individuals interviewed and household families was 1.1 ± 0.26 (1-2) and 3.5 ± 2.23 (1-10), respectively. It was further observed that out of 138 livestock keepers interviewed, 133 (96.4 %) had feature phones while 10 (7.2 %) of them possessed smartphones. Mobile phone is currently used to support livestock production by communicating on animal health in Parakuyo (18, 41.9 %), Mvumi (18, 43.9 %) and Chakwale (14, 25.9 %). Other contributions of mobile phones in livestock and crop agriculture observed in the study area include: exchange of livestock price information, crop price information, communicating on plant health/diseases, livestock extension and advisory services as well as crop farming extension and advisory services. We also designed and tested an e-based SUAVetDiag® system to support timely diagnosis of infectious disease conditions and prompt advice on case management in veterinary underserved areas. CONCLUSIONS: Availability of mobile phones in rural areas, in combination with supporting infrastructure and facilities in urban areas, has potential to stimulate local development and improving delivery of animal health and extension services. It is recommended that more development and refinement of the system should be conducted to ensure that this potential is tapped to revolutionalise delivery of animal health services in rural areas.

Isolation of Treponema DNA from Necrophagous Flies in a Natural Ecosystem.

BACKGROUND: Recently, the World Health Organization launched a campaign to eradicate the tropical disease yaws, caused by the bacterium Treponema pallidum subsp. pertenue; however, for decades researchers have questioned whether flies act as a vector for the pathogen that could facilitate transmission. METHODS: A total of 207 fly specimens were trapped in areas of Africa in which T. pallidum-induced skin ulcerations are common in wild baboons; 88 flies from Tarangire National Park and 119 from Lake Manyara National Park in Tanzania were analyzed by PCR for the presence of T. pallidum DNA. FINDINGS: We report that in the two study areas, T. pallidum DNA was found in 17-24% of wild-caught flies of the order Diptera. Treponemal DNA sequences obtained from many of the flies match sequences derived from nearby baboon T. pallidum strains, and one of the fly species with an especially high prevalence of T. pallidum DNA, Musca sorbens, has previously been shown to transmit yaws in an experimental setting. INTERPRETATION: Our results raise the possibility that flies play a role in yaws transmission; further research is warranted, given how important understanding transmission is for the eradication of this disfiguring disease.

Validation of serological tests for the detection of antibodies against Treponema pallidum in nonhuman primates.

There is evidence to suggest that the yaws bacterium (Treponema pallidum ssp. pertenue) may exist in non-human primate populations residing in regions where yaws is endemic in humans. Especially in light of the fact that the World Health Organizaiton (WHO) recently launched its second yaws eradication campaign, there is a considerable need for reliable tools to identify treponemal infection in our closest relatives, African monkeys and great apes. It was hypothesized that commercially available serological tests detect simian anti-T. pallidum antibody in serum samples of baboons, with comparable sensitivity and specificity to their results on human sera. Test performances of five different treponemal tests (TTs) and two non-treponemal tests (NTTs) were evaluated using serum samples of 57 naturally T. pallidum-infected olive baboons (Papio anubis) from Lake Manyara National Park in Tanzania. The T. pallidum particle agglutination assay (TP-PA) was used as a gold standard for comparison. In addition, the overall infection status of the animals was used to further validate test performances. For most accurate results, only samples that originated from baboons of known infection status, as verified in a previous study by clinical inspection, PCR and immunohistochemistry, were included. All tests, TTs and NTTs, used in this study were able to reliably detect antibodies against T. pallidum in serum samples of infected baboons. The sensitivity of TTs ranged from 97.7-100%, while specificity was between 88.0-100.0%. The two NTTs detected anti-lipoidal antibodies in serum samples of infected baboons with a sensitivity of 83.3% whereas specificity was 100%. For screening purposes, the TT Espline TP provided the highest sensitivity and specificity and at the same time provided the most suitable format for use in the field. The enzyme immune assay Mastblot TP (IgG), however, could be considered as a confirmatory test.

Treponema pallidum infection in the wild baboons of East Africa: distribution and genetic characterization of the strains responsible.

It has been known for decades that wild baboons are naturally infected with Treponema pallidum, the bacterium that causes the diseases syphilis (subsp. pallidum), yaws (subsp. pertenue), and bejel (subsp. endemicum) in humans. Recently, a form of T. pallidum infection associated with severe genital lesions has been described in wild baboons at Lake Manyara National Park in Tanzania. In this study, we investigated ten additional sites in Tanzania and Kenya using a combination of macroscopic observation and serology, in order to determine whether the infection was present in each area. In addition, we obtained genetic sequence data from six polymorphic regions using T. pallidum strains collected from baboons at two different Tanzanian sites. We report that lesions consistent with T. pallidum infection were present at four of the five Tanzanian sites examined, and serology was used to confirm treponemal infection at three of these. By contrast, no signs of treponemal infection were observed at the six Kenyan sites, and serology indicated T. pallidum was present at only one of them. A survey of sexually mature baboons at Lake Manyara National Park in 2006 carried out as part of this study indicated that roughly ten percent displayed T. pallidum-associated lesions severe enough to cause major structural damage to the genitalia. Finally, we found that T. pallidum strains from Lake Manyara National Park and Serengeti National Park were genetically distinct, and a phylogeny suggested that baboon strains may have diverged prior to the clade containing human strains. We conclude that T. pallidum infection associated with genital lesions appears to be common in the wild baboons of the regions studied in Tanzania. Further study is needed to elucidate the infection's transmission mode, its associated morbidity and mortality, and the relationship between baboon and human strains.