Full text: Available Index: IMSEAR (South-East Asia) Main subject: Travel / Humans / Drug Resistance / Seroepidemiologic Studies / China / Population Surveillance / Incidence / Prevalence / Health Surveys / Emigration and Immigration Type of study: Incidence study / Prevalence study / Prognostic study / Screening study Country/Region as subject: Asia Language: English Journal: Southeast Asian J Trop Med Public Health Year: 1994 Type: Article