title: Declining Trend of Hepatitis A Seroepidemiology in Association with Improved Public Health and Economic Status of Thailand.
abstract: Hepatitis A virus (HAV) is transmitted via the fecal-oral route from contaminated food or water. As part of the most recent survey of viral hepatitis burden in Thailand, we analyzed the current seroprevalence of HAV in the country and compared with data dating back to 1971. From March to October, 2014, a total of 4,260 individuals between one month and 71 years of age from different geographical regions (North = 961; Central = 1,125; Northeast = 1,109; South = 1,065) were screened for anti-HAV IgG antibody using an automated chemiluminescent microparticle immunoassay. Overall, 34.53% (1,471/4,260) possessed anti-HAV IgG antibody, and the age-standardized seroprevalence was 48.6%. Seroprevalence rates were 27.3% (North), 30.8% (Central), 33.8% (Northeast) and 45.8% (South) and were markedly lower than in the past studies especially among younger age groups. The overall trend showed an increase in the age by which 50% of the population were anti-HAV IgG antibody: 4.48 years (1971-1972), 6 (1976), 12.49 (1990), 36.02 (2004) and 42.03 (2014).This suggests that Thailand is transitioning from low to very low HAV endemicity. Lower prevalence of HAV correlated with improved healthcare system as measured by decreased infant mortality rate and improved national economy based on increased GDP per capita. The aging HAV immuno-naïve population may be rendered susceptible to potential HAV outbreaks similar to those in industrialized countries and may benefit from targeted vaccination of high-risk groups.
authors.affiliation: Center of Excellence in Clinical Virology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Pathum Wan, Bangkok, Thailand.
authors.forename: Pattaratida
authors.initials: P
authors.lastname: Sa-nguanmoo
authors.affiliation: Center of Excellence in Clinical Virology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Pathum Wan, Bangkok, Thailand.
authors.forename: Nawarat
authors.initials: N
authors.lastname: Posuwan
authors.affiliation: Center of Excellence in Clinical Virology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Pathum Wan, Bangkok, Thailand.
authors.forename: Preeyaporn
authors.initials: P
authors.lastname: Vichaiwattana
authors.affiliation: Chumphae Hospital, Chum Phae, Khon Kaen, Thailand.
authors.forename: Viboonsak
authors.initials: V
authors.lastname: Vuthitanachot
authors.affiliation: Chumphae Hospital, Chum Phae, Khon Kaen, Thailand.
authors.forename: Siriporn
authors.initials: S
authors.lastname: Saelao
authors.affiliation: Uttaradit Hospital, Mueang Uttaradit, Uttaradit, Thailand.
authors.forename: Monthana
authors.initials: M
authors.lastname: Foonoi
authors.affiliation: Uttaradit Hospital, Mueang Uttaradit, Uttaradit, Thailand.
authors.forename: Apinya
authors.initials: A
authors.lastname: Fakthongyoo
authors.affiliation: Laplae Hospital, Laplae, Uttaradit, Thailand.
authors.forename: Jamorn
authors.initials: J
authors.lastname: Makaroon
authors.affiliation: Naresuan University Hospital, Mueang Phitsanulok, Phitsanulok, Thailand.
authors.forename: Klaita
authors.initials: K
authors.lastname: Srisingh
authors.affiliation: Phra Nakhon Si Ayutthaya Hospital, Phra Nakhon Si Ayutthaya, Thailand.
authors.forename: Duangporn
authors.initials: D
authors.lastname: Asawarachun
authors.affiliation: King Narai Hospital, Mueang Lop Buri, Lop Buri, Thailand.
authors.forename: Somchai
authors.initials: S
authors.lastname: Owatanapanich
authors.affiliation: Narathiwat Ratchanakarin Hospital, Mueang Narathiwat, Narathiwat, Thailand.
authors.forename: Norra
authors.initials: N
authors.lastname: Wutthiratkowit
authors.affiliation: Trang Hospital, Mueang Trang, Trang, Thailand.
authors.forename: Kraisorn
authors.initials: K
authors.lastname: Tohtubtiang
authors.affiliation: Center of Excellence in Clinical Virology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Pathum Wan, Bangkok, Thailand.
authors.forename: Sompong
authors.initials: S
authors.lastname: Vongpunsawad
authors.affiliation: Bureau of Epidemiology, Department of Disease Control, Ministry of Public Health, Mueang Nonthaburi, Nonthaburi, Thailand.
authors.forename: Pornsak
authors.initials: P
authors.lastname: Yoocharoen
authors.affiliation: Center of Excellence in Clinical Virology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Pathum Wan, Bangkok, Thailand.
authors.forename: Yong
authors.initials: Y
authors.lastname: Poovorawan
mesh_terms: D005843:Geography; D006506:Hepatitis A / Q000453:epidemiology*; D006801:Humans; D015980:Public Health Practice; D016036:Seroepidemiologic Studies; D012923:Social Class; D013785:Thailand / Q000453:epidemiology