title: Clinical Features and Transmission Pattern of Hepatitis A: An Experience from a Hepatitis A Outbreak Caused by Two Cocirculating Genotypes in Sri Lanka.
abstract: Sri Lanka is one of the intermediate-endemic areas for hepatitis A virus (HAV), and concerns exist about the increasing HAV-susceptible population. In fact, Sri Lanka recorded a large hepatitis outbreak, possibly hepatitis A, around the end of the Sri Lankan war. It included more than 14,000 patients consisting of local residents, internally displaced personnel, and military personnel in the main combat zone. The outbreak had slowed down by October 2009; however, acute viral hepatitis continued to occur sequentially among military personnel. We obtained clinical information and serum samples from 222 patients with acute hepatitis who visited the Military Hospital Anuradhapura between January and September 2010. Samples were subjected to laboratory testing including HAV-immunoglobulin M and genotyping. Most patients (98.2%) were confirmed as having hepatitis A belonging to two subgenotypes: IA and IIIA. We did not observe any differences in clinical or biochemical features among patients with subgenotypes IA and IIIA except for pale stools and upper abdominal discomfort. During the investigation period, we observed a serial outbreak caused by identical HAV strains with an interval in line with that of typical HAV incubation periods. Most patients in the first outbreak were found in the training center, and patients in the second outbreak were found in multiple places where soldiers were assigned after the training center. These findings indicate that a strain of HAV diffused from one place to another along with movement of infected persons among the HAV-susceptible population. HAV vaccination for high-risk groups, such as young soldiers, is necessary.
authors.affiliation: Department of Medicine, Faculty of Medicine and Allied Sciences, Rajarata University of Sri Lanka, Saliyapura, Sri Lanka.
authors.forename: Niroshana J
authors.initials: NJ
authors.lastname: Dahanayaka
authors.affiliation: Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan. kiyohara@niid.go.jp.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Kiyohara
authors.affiliation: Department of Community Medicine, Faculty of Medicine and Allied Sciences, Rajarata University of Sri Lanka, Saliyapura, Sri Lanka.
authors.forename: Suneth B
authors.initials: SB
authors.lastname: Agampodi
authors.affiliation: Military Hospital, Anuradhapura, Sri Lanka.
authors.forename: Pradeep K
authors.initials: PK
authors.lastname: Samaraweera
authors.affiliation: Military Hospital, Anuradhapura, Sri Lanka.
authors.forename: Gayani K
authors.initials: GK
authors.lastname: Kulasooriya
authors.affiliation: Department of Medicine, Faculty of Medicine and Allied Sciences, Rajarata University of Sri Lanka, Saliyapura, Sri Lanka.
authors.forename: Jagath C
authors.initials: JC
authors.lastname: Ranasinghe
authors.affiliation: Department of Public Health, Sri Lanka Army Medical Services, Colombo, Sri Lanka.
authors.forename: Saveen N
authors.initials: SN
authors.lastname: Semage
authors.affiliation: Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Yoshizaki
authors.affiliation: Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Takaji
authors.initials: T
authors.lastname: Wakita
authors.affiliation: Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Ishii
mesh_terms: D015746:Abdominal Pain / Q000453:epidemiology; D000293:Adolescent; D000328:Adult; D000855:Anorexia / Q000453:epidemiology; D004196:Disease Outbreaks; D005334:Fever / Q000453:epidemiology; D005838:Genotype; D006506:Hepatitis A / Q000453:epidemiology / Q000276:immunology / Q000635:transmission / Q000821:virology*; D035922:Hepatitis A Antibodies / Q000276:immunology; D030041:Hepatitis A virus / Q000235:genetics*; D006801:Humans; D007075:Immunoglobulin M / Q000276:immunology; D008297:Male; D008889:Military Personnel / Q000706:statistics & numerical data*; D009325:Nausea / Q000453:epidemiology; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000097:blood; D013188:Sri Lanka; D055815:Young Adult
chemical_list: D035922:Hepatitis A Antibodies; D007075:Immunoglobulin M; D012367:RNA, Viral