A One Health investigation of Salmonella enterica serovar Wangata in north-eastern New South Wales, Australia, 2016-2017.

Salmonella enterica serovar Wangata (S. Wangata) is an important cause of endemic salmonellosis in Australia, with human infections occurring from undefined sources. This investigation sought to examine possible environmental and zoonotic sources for human infections with S. Wangata in north-eastern New South Wales (NSW), Australia. The investigation adopted a One Health approach and was comprised of three complimentary components: a case-control study examining human risk factors; environmental and animal sampling; and genomic analysis of human, animal and environmental isolates. Forty-eight human S. Wangata cases were interviewed during a 6-month period from November 2016 to April 2017, together with 55 Salmonella Typhimurium (S. Typhimurium) controls and 130 neighbourhood controls. Indirect contact with bats/flying foxes (S. Typhimurium controls (adjusted odds ratio (aOR) 2.63, 95% confidence interval (CI) 1.06-6.48)) (neighbourhood controls (aOR 8.33, 95% CI 2.58-26.83)), wild frogs (aOR 3.65, 95% CI 1.32-10.07) and wild birds (aOR 6.93, 95% CI 2.29-21.00) were statistically associated with illness in multivariable analyses. S. Wangata was detected in dog faeces, wildlife scats and a compost specimen collected from the outdoor environments of cases' residences. In addition, S. Wangata was detected in the faeces of wild birds and sea turtles in the investigation area. Genomic analysis revealed that S. Wangata isolates were relatively clonal. Our findings suggest that S. Wangata is present in the environment and may have a reservoir in wildlife populations in north-eastern NSW. Further investigation is required to better understand the occurrence of Salmonella in wildlife groups and to identify possible transmission pathways for human infections.

Spatiotemporal evidence for cross-border spread of MDR-TB along the Trans-Siberian Railway line.

BACKGROUND: Mongolia has the fifth highest incidence of tuberculosis (TB) in the Western Pacific Region, with high rates of multidrug-resistant TB (MDR-TB). OBJECTIVE: To examine the recent spatiotemporal dynamics of MDR-TB in Mongolia. METHODS: All MDR-TB cases diagnosed from 2004 to 2012, identified from the National Tuberculosis Control Programme database, were included in the study. Cases diagnosed from 2006 to 2012 were further examined using spatial scan statistics. RESULTS: Few MDR-TB cases (n = 29) were diagnosed before the programmatic management of MDR-TB was introduced in 2006. During 2006-2012, 1106 MDR-TB cases were detected, at an annualised rate of 5.9 cases per 100 000 population. Most (>80%) cases were identified in the 15-44 year age group; 45% were among those aged 15-29 years. Case notification rates were highest in the capital city, Ulaanbaatar, with an increasing trend over time in all locations. Three MDR-TB hotspots were identified, all in close proximity to the Trans-Siberian Railway line. The majority of the MDR-TB isolates were resistant to all first-line drugs tested. CONCLUSION: Spatiotemporal analysis indicates likely cross-border spread of MDR-TB along the Trans-Siberian Railway line, with subsequent spatial expansion across Mongolia. The frequency of MDR-TB among young patients with pan-resistance to all first-line drugs suggests ongoing MDR-TB transmission within the community.