Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

Use of molecular methods to detect shedding of mycobacterium bovis in cattle faeces and milk

Masters ThesisBovine tuberculosis (BTB) is a chronic bacterial disease caused by Mycobacterium bovis. It affects cattle and occasionally other animals and human. Several techniques exist for detection of BTB in animals. In Tanzania, Single Intradermal Comparative Tuberculin Test (SCITT) and abattoir meat inspection are the commonly used methods for screening of BTB. This study has used molecular biology method namely; RD4 Real time PCR (RD4 Rt PCR) to detect shedding M. bovis in milk and faecal samples from cattle tested by SCITT and Bovigam test. The study has also determined the detection limit of Immunomagnetic capture (IMC) and Centrifugation methods of M. bovis cells in spiked milk. A total of 63 cattle dairy form LITA farm Morogoro were tested for BTB with SCITT and Bovigam test. Faecal and milk samples were collected and RD4 Rt PCR was used to detect M. bovis DNA. BTB prevalence detected by SCITT and Bovigam was 3.1% and 3.1% respectively and BTB prevalence detected by RD4 Rt PCR in milk and faeces was 36.1% and 9.5% respectively. The kappa value between the SCITT and Bovigam was 1 and between shedding of M. bovis in milk and faeces detected using RD4 Rt PCR was 0.07. The detection limit of IMC and centrifugation coupled with Real time PCR ranges from 100 to 1 000 M. bovis cells per 500 μl milk and 10 to 100 M. bovis cells per 500 μl milk sample. High number of cattle was detected by Real time PCR to have BTB compared to SCITT or Bovigam. The confirmation of M. bovis in milk indicates potential root of transmission of M. bovis from cow to calf also to human who consume raw milk. Moreover, confirmation of M. bovis in feces indicates possible contamination of cattle carcasses during slaughter process. The study proposes that in order to improve BTB diagnosis for controlling and management of BTB, both conventional, SCITT or Bovigam and molecular methods in feces and milk need to be deployed in parallel but considering their own merits like cost and repeat access to animals.Wellcome Trust (Grant WT087546MA) Southern African Centre for Infectious disease (SACIDS) and National Institute for Health (Grant 5U01A1088679-05

Rotavirus Burden, Genetic Diversity and Impact of Vaccine in Children under Five in Tanzania

In Tanzania, rotavirus infections are responsible for 72% of diarrhea deaths in children under five. The Rotarix vaccine was introduced in early 2013 to mitigate rotavirus infections. Understanding the disease burden and virus genotype trends over time is important for assessing the impact of rotavirus vaccine in Tanzania. When assessing the data for this review, we found that deaths of children under five declined after vaccine introduction, from 8171/11,391 (72% of diarrhea deaths) in 2008 to 2552/7087 (36% of diarrhea deaths) in 2013. Prior to vaccination, the prevalence of rotavirus infections in children under five was 18.1–43.4%, 9.8–51%, and 29–41% in Dar es Salaam, Mwanza and Tanga, respectively, and after the introduction of vaccines, these percentages declined to 17.4–23.5%, 16–19%, and 10–29%, respectively. Rotaviruses in Tanzania are highly diverse, and include genotypes of animal origin in children under five. Of the genotypes, 10%, 28%, and 7% of the strains are untypable in Dar es Salaam, Tanga, and Zanzibar, respectively. Mixed rotavirus genotype infection accounts for 31%, 29%, and 12% of genotypes in Mwanza, Tanga and Zanzibar, respectively. The vaccine effectiveness ranges between 53% and 75% in Mwanza, Manyara and Zanzibar. Rotavirus vaccination has successfully reduced the rotavirus burden in Tanzania; however, further studies are needed to better understand the relationship between the wildtype strain and the vaccine strain as well as the zoonotic potential of rotavirus in the post-vaccine era

Camels, diamonds and counterfactuals : A model for teaching causal

Primers used in this study. (DOC 26 kb

Toxigenic Vibrio cholerae O1 in vegetables and fish raised in wastewater irrigated fields and stabilization ponds during a non-cholera outbreak period in Morogoro, Tanzania:an environmental health study

BACKGROUND: Cholera, one of the world’s deadliest infectious diseases, remains rampant and frequent in Tanzania and thus hinders existing control measures. The present study was undertaken to evaluate the occurrence of toxigenic Vibrio cholerae O1 in wastewater, fish and vegetables during a non-outbreak period in Morogoro, Tanzania. METHODS: From October 2014 to February 2015, 60 wastewater samples, 60 fish samples from sewage stabilization ponds and 60 wastewater irrigated vegetable samples were collected. Samples were cultured for identification of V. cholerae using conventional bacteriological methods. Isolates were confirmed as V. cholerae by detection of the outer membrane protein gene (ompW) using polymerase chain reaction (PCR). Isolates were further tested for antibiotic susceptibility and presence of virulence genes including, cholera enterotoxin gene (ctx), the toxin co-regulated pilus gene (tcpA) and the haemolysin gene (hlyA). RESULTS: The prevalence of V. cholerae in wastewater, vegetables and fish was 36.7, 21.7 and 23.3 %, respectively. Two isolates from fish gills were V. cholerae O1 and tested positive for ctx and tcpA. One of these contained in addition the hlyA gene while five isolates from fish intestines tested positive for tcpA. All V. cholerae isolates were resistant to ampicillin, amoxicillin and some to tetracycline, but sensitive to gentamicin, chloramphenicol, and ciprofloxacin. CONCLUSIONS: Our results show that toxigenic and drug-resistant V. cholerae O1 species are present and persist in aquatic environments during a non-cholera outbreak period. This is of public health importance and shows that such environments may be important as reservoirs and in the transmission of V. cholerae O1