To investigate susceptibility to and factors associated with rubella infection among pregnant mothers and to estimate the burden of congenital rubella infection (CRI) in Vietnam where rubella-containing vaccine (RCV) is not included in the routine immunization programme, we conducted a prospective cohort study

BackgroundDiabetes Mellitus (DM) has rapidly become a major public health concern in Vietnam. Although the prevalence of DM has been studied in northern and southern Vietnam, little data are available for the central region. Therefore, the aims of this survey were to estimate the prevalence of DM and to identify the perception of and factors associated with DM among the adult population in central Vietnam.MethodsWe conducted a cross-sectional, population-based survey in Khánh Hòa Province, Vietnam in December 2014 using three-stage cluster sampling and probability proportional to size sampling in line with the World Health Organization STEPwise approach. Four hundred and eighty residents aged 20–70 years were selected from 30 villages in 10 wards/communes. After obtaining informed consent, all residents participated in interviews regarding lifestyle, medical history, and perception of DM and underwent physical measurements and blood examination for fasting blood glucose and glycated hemoglobin. Factors associated with DM were analyzed using a logistic regression model.ResultsA total of 376 residents were enrolled (response rate: 78.3%; females: 59%; rural residents: 61%). Among the participants, 14.3% and 18.9% of males and females, respectively, were classified as overweight/obese according to body mass index (BMI), 37.7% and 22.1%, respectively, had hypertension, and 36.4% and 11.7% had metabolic syndrome. The prevalence of DM in the entire population was 7.2% (27/376; 95% confidence interval [CI]: 4.6–9.8). Participants aged 60–70 years were more likely to have DM than those aged 30–39 years (adjusted odds ratio [aOR]: 8.7; 95%CI: 1.4–56.0), and participants classified as obese were more likely to have DM than those with normal or low BMI (aOR: 10.2; 95%CI: 2.2–50.2). Furthermore, more than two-thirds (254/376, 67.6%) of the participants either did not understand or had never heard of DM, and less than half of the DM cases (12/27, 44%) were aware of their history of DM.ConclusionsThe results of this study suggested that the prevalence of DM among the adult population in central Vietnam was slightly higher than that in other areas. Additional research is needed to further explore perceptions of and practices regarding DM.

Supported by GAVI Alliance, measles-rubella vaccination was introduced in Vietnam in 2014, involving a mass campaign among 1-14 year olds and routine immunization of children aged 9 months. We explore the impact on the incidence of Congenital Rubella Syndrome (CRS) during 2013-2050 of this strategy and variants involving women aged 15-35 years. We use an age and sex-structured dynamic transmission model, set up using recently-collected seroprevalence data from Central Vietnam, and also consider different levels of transmission and contact patterns. If the serological profile resembles that in Central Vietnam, the planned vaccination strategy could potentially prevent 125,000 CRS cases by 2050 in Vietnam, despite outbreaks predicted in the meantime. Targeting the initial campaign at 15-35 year old women with or without children aged 9 months-14 years led to sustained reductions in incidence, unless levels of ongoing transmission were medium-high before vaccination started. Assumptions about contact greatly influenced predictions if the initial campaign just targeted 15-35 year old women and/or levels of ongoing transmission were medium-high. Given increased interest in rubella vaccination, resulting from GAVI Alliance funding, the findings are relevant for many countries.

A population-based cohort study on pediatric infectious diseases was established at Khanh Hoa Province, central Vietnam in 2006, to determine the etiology and risk factors for severe pediatric infectious diseases (SPID) such as acute respiratory infection (ARI), diarrhea and dengue which are the major causes of under 5 mortality. A population census survey was conducted in Nha-Trang and Ninh-Hoa to collect demographic, social-behavioral data and disease burden on SPID. The study site covered a population of 353,525 residing in 75,826 households with 24,781 children less than 5 years. Hospital databases from two hospitals covering the region were obtained. Linking the census and hospital databases, we were able to investigate on a variety of SPID such as environmental tobacco smoking exposure and increased risked of pediatric pneumonia hospitalization, population density, water supply and risk of dengue fever and animal livestock and risk of hospitalized diarrhea. To determine incidence, viral etiology and risk factors for pediatric ARI/pneumonia, we setup a population based prospective hospitalized Pediatric ARI surveillance at Khanh Hoa General Hospital, Nha-Trang in February 2007. The study has revealed RSV, rhinovirus and influenza A as major viral pathogens, role of multiple viral infection and its interaction with bacteria in the development of pneumonia. In addition, we are also conducting a birth cohort study to investigate the incidence of congenital infection and its impact on physical-neurological development, and role of host genetic polymorphism on SPID hospitalization in Vietnam. Population mobility, high cost of regular census update and low mortality are the challenges.

A birth cohort study was conducted in Khan Hoa Province, central Vietnam between 2009 and 2012 to determine the seroprevalence of hepatitis B virus (HBV) in pregnant women and their children, and associated risk factors. We enrolled 1987 pregnant women with their babies at the birth phase, and 12.6% (95% confidence interval [CI]: 11.1–14.0) of mothers were hepatitis B surface antigen (HBsAg)+. At 2-year follow-up phase, 1339 (67.4%) children were enrolled of whom 76.6% completed hepatitis B vaccines (HepB) and 1.9% (95% CI: 1.2–2.7) were HBsAg+. When mothers were hepatitis B e antigen (HBeAg)+, 28.3% of children have got infected even with complete HepB. HBV infection in mothers, hepatitis B surface antibody (anti-HBs antibody) below the seroprotective level in children, and mothers with pre-pregnancy low body mass index were associated with HBV infection in children. Meanwhile, HBV infection in children, older maternal age, no or incomplete doses of HepB, and boys were associated with anti-HBs antibody below the seroprotective level in children. Our birth cohort study determined a low rate of congenital HBV infection and associated risk factors in Vietnam, however further studies are needed to advance prevention including anti-viral therapy in pregnant women at high risk.