Seroepidemiology of Japanese Encephalitis Virus Infection in Hualien, Taiwan

NCT01163123 | Unknown

• 1 other identifier: D9902
• Study Type: observational
• Target: 312
• Locations: 0 countries
• Sites: N/A

Brief Summary

Japanese encephalitis (JE) is one of important zoonotic infectious diseases in Taiwan. JE caused by Japanese encephalitis virus (JEV) which transmitted by Culex tritaeniorhynchus and used swine as amplifying host. Infections leading to overt encephalitis are estimated to be 1 in 1000 cases. Among JE confirmed cases, approximately 25 percent of cases die and 50 percent of the survivals develop permanent neurologic and/or psychiatric sequelae. JEV circulated in Taiwan are belonged to genotype III and the vaccine strain selected from same genotype. Genotype I JEV was first detected in northern Taiwan in 2008 by CDC, and the same genotype JEV were detected in mosquito collected in central Taiwan by our group. In order to study the genotypic shift of JEV in Taiwan areas, and the effects of the replacement of genotype on vaccine, we will conduct the JEV seroepidemiology in Hualien county which was the highest incidence of JEV in Taiwan. The aims of this study were: (1) study the circulating of genotype I JEV in Hualien county; (2) determine the virulence of genotype I JEV in human; (3) differential diagnosis of JEV genotype I or III infection among confirmed cases; (4) measure the cross neutralizing activity, after immunized with genotype III JEV vaccine, against genotype I JEV; (5) determine the age-specific seroprevalence of JEV antibody; (6) estimate the annual risk of infection for JEV.

Conditions

Japanese Encephalitis

Keywords

Subclinical infection of Japanese encephalitis virus

Outcome Measures

Primary Outcomes (1)

• Measure the subclinical infection rate in the cohort population during the summer ( May 2010 ~ Sep 2010)

  We exam 2 sera from volunteer collected seperately on May and October 2010 to estimate the subclinical infection rate. Subclinical infection rate was defined by one of the following 1. 4 times increased in IgG titer 2. Appearance of IgM in the second sera 3. Apperance of Anti-NS1 antibody in the second sera

  May 2010 - Oct 2010

Eligibility Criteria

• Age: 18 Years - 85 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Volunteers were recruited from 2 villages in Hualien county Taiwan. There were at least one patient who had confirmed diagnosis of Japanese virus encephalitis in past 2 years. Many pig farms were located in these 2 villages also. The volunteers are either living or working in the villages during 2010 summer. We had blood test for IgM, IgG for Japanese virus encephalitis before and after the summer season to identify possible subclinical infection. At the same time, mosquito were analyzed by RT-PCR periodically to identify possible virus in the community.

You may qualify if:

• Living in the specific 2 villages in Hualien county
• Aged 18-85

You may not qualify if:

• \. Difficulty to have blood test due to coagulopathy or small blood vessels

Sponsors & Collaborators

• Mennonite Christian Hospital: lead

Biospecimen

Retention: SAMPLES WITHOUT DNA

The sera from volunteer was collected to detect IgG, IgM and anti-NS1 antibody against Japanese encephalitis virus

MeSH Terms

Conditions

Encephalitis, Japanese

Condition Hierarchy (Ancestors)

Encephalitis, Arbovirus; Encephalitis, Viral; Central Nervous System Viral Diseases; Central Nervous System Infections; Infections; Infectious Encephalitis; Arbovirus Infections; Vector Borne Diseases; Mosquito-Borne Diseases; Virus Diseases; RNA Virus Infections; Flavivirus Infections; Flaviviridae Infections; Encephalitis; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neuroinflammatory Diseases

Study Officials

• ChenChang Shih

  STUDY DIRECTOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: July 14, 2010
• First Posted: July 15, 2010
• Study Start: May 1, 2010
• Primary Completion: December 1, 2010
• Study Completion: December 1, 2010
• Last Updated: July 16, 2010

Record last verified: 2010-07