Increases in both HIV and syphilis among men who have sex with men in Vietnam: Urgent need for comprehensive responses.

The objective of this study was to determine the temporal trends and factors associated with HIV and syphilis infection among men who have sex with men (MSM) in southern Vietnam. Data from the 2014-2018 national HIV sentinel surveillance of MSM aged 16 years or older were collected from three provinces, including An Giang (N = 761), Can Tho (N = 900), and Ho Chi Minh City (N = 1426), and examined for changes in prevalence rates of HIV and syphilis and risk behaviors over time. Multivariate logistic regression was performed to assess the trends and correlates of HIV and syphilis infections among MSM. There were upward trends for HIV (9.5% in 2014 to 14.2% in 2018, p-trend<0.01), syphilis (4.9% in 2014 to 8.0% 2018, p-trend<0.01), and HIV/syphilis co-infection (1.9% in 2014 to 3.1% in 2018, p-trend=0.01). Factors associated with HIV infection included place of residence, early sexual debut, consistent condom use and not engaging in anal sex during the past month, not knowing one's HIV test results, having ever injected drugs, and having active syphilis. Additionally, early sexual debut and being HIV positive were associated with syphilis infection. Rising prevalences of these infections among MSM suggests an urgent need for comprehensive intervention packages for HIV/STI prevention.

Low entomological impact of new water supply infrastructure in southern Vietnam, with reference to dengue vectors.

We did a prospective study in southern Vietnam where new water infrastructure was added. New 1,200-L tanks may present potential breeding grounds for Aedes aegypti, particularly when sealed lids were not always supplied. Some householders in these communes received a piped water supply, however there was no reduction in water storage practices. The prevalence of Aedes aegypti immatures in tank and tap households reached 73%, but were non-significantly different from each other and from control households that received no infrastructure. In all three communes, standard jars comprised from 48% to 71% of containers but were associated with > 90% of III-IV instars and pupae on occasions. In contrast, project tanks contributed from 0-21% of the total population. Non-functional or no lids were apparent 4 months after installation in 45-76% of new tanks, but there was no difference between communes with lids and without lids.

Householder perspectives and preferences on water storage and use, with reference to dengue, in the Mekong Delta, southern Vietnam.

Community-based perceptions and behaviour around water source preference, household water storage patterns and water use, and householders' knowledge and behaviour with respect to dengue etiology and transmission, were examined in three communes located in the Mekong Delta area in southern Vietnam. Through focus group discussions, most participants identified poorly screened or uncovered water containers (including household water storage containers and other types of artificial containers) as habitats for mosquitoes that transmit dengue viruses, and thereby demonstrated a clear understanding of the links between household water storage practices and the threat of dengue. Our qualitative analyses also revealed broader community-based concerns about the limited availability of water and strong preferences for storage of rainwater based upon perceptions of cost, quality and security of supply. These perceptions are central to shaping householders' responses to water infrastructure projects. The limited availability of water during the dry season and insufficient numbers of water storage containers are over-riding community concerns which provide an important context to understanding community behaviours and responses to public health interventions against dengue. Such concerns are important precursors to selecting the type of intervention.