Suchergebnisse

Background: The spread of infectious diseases from person to person is determined by the frequency and nature of contacts between infected and susceptible members of the population. Although there is a long history of using mathematical models to understand these transmission dynamics, there are still remarkably little empirical data on contact behaviors with which to parameterize these models. Even starker is the almost complete absence of data from developing countries. We sought to address this knowledge gap by conducting a household based social contact diary in rural Vietnam. Methods and Findings: A diary based survey of social contact patterns was conducted in a household-structured community cohort in North Vietnam in 2007. We used generalized estimating equations to model the number of contacts while taking into account the household sampling design, and used weighting to balance the household size and age distribution towards the Vietnamese population. We recorded 6675 contacts from 865 participants in 264 different households and found that mixing patterns were assortative by age but were more homogenous than observed in a recent European study. We also observed that physical contacts were more concentrated in the home setting in Vietnam than in Europe but the overall level of physical contact was lower. A model of individual versus household vaccination strategies revealed no difference between strategies in the impact on R-0. Conclusions and Significance: This work is the first to estimate contact patterns relevant to the spread of infections transmitted from person to person by non-sexual routes in a developing country setting. The results show interesting similarities and differences from European data and demonstrate the importance of context specific data. ; This work was supported by the Wellcome Trust UK (grants 081613/Z/06/Z and 077078/Z/05/Z). NH gratefully acknowledges financial support from "SIMID", a strategic basic research project funded by the Institute for the Promotion of Innovation by Science and Technology in Flanders (IWT), project number 060081 and by the IAP research network number P6/03 of the Belgian Government (Belgian Science Policy). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

AbstractAlthough there are now several instruments available to measure social capital in a quantitative manner, very few of them have been validated, and no published study has examined respondents' interpretation of the meaning of the questions. This article represents one of the first attempts to measure the validity of a quantitative social capital instrument. Young Lives is a study that includes quantitative measures of caregivers' social capital using the Short Adapted Social Capital Assessment Tool (Short A-SCAT). Vietnamese respondents' interpretations of questions on social capital were compared to the original intended meaning of the questions and to fieldworkers' interpretations. Semi-structured interviews were conducted with two interpreters who were involved in translating the original questionnaire from English to Vietnamese, two supervisors and six interviewers. In-depth interviews were conducted with 24 female caregivers similar to the original respondents. Key concepts in social capital, like trust and sense of belonging, were interpreted similarly by all actors. Support was perceived narrowly by caregivers (limited to money and goods). Most problems arose from changes originating from translation from English to Vietnamese and by the changing nature of local political structures and how one refers to them. Overall validity appeared fairly high with a "correct interpretation" rate of 77 percent. There is now a valid tool for quickly and cheaply assessing social capital in a quantitative manner in Vietnam.