Litchi–associated Acute Encephalitis in Children, Northern Vietnam, 2004–2009

• Main Authors: Juliette Paireau, Nguyen Hai Tuan, Rémi Lefrançois, Matthew R. Buckwalter, Ngu Duy Nghia, Nguyen Tran Hien, Olivier Lortholary, Sylvain Poirée, Jean-Claude Manuguerra, Antoine Gessain, Matthew L. Albert, Paul T. Brey, Phan Thi Nga, Arnaud Fontanet
• Format: Article
• Language: English
• Published: Centers for Disease Control and Prevention 2012-11-01
• Series: Emerging Infectious Diseases
• Subjects: Encephalitis; epidemics; disease outbreaks; epidemiology; risk factors; litchi
• Online Access: https://wwwnc.cdc.gov/eid/article/18/11/11-1761_article

Since the end of the 1990s, unexplained outbreaks of acute encephalitis in children coinciding with litchi harvesting (May–July) have been documented in the Bac Giang Province in northern Vietnam. A retrospective ecologic analysis of data for 2004–2009 involving environmental, agronomic, and climatic factors was conducted to investigate the suspected association between the outbreaks and litchi harvesting. The clinical, biological, and immunologic characteristics of the patients suggested a viral etiology. The ecologic study revealed an independent association between litchi plantation surface proportion and acute encephalitis incidence: Incidence rate ratios were 1.52 (95% CI 0.90–2.57), 2.94 (95% CI 1.88–4.60), and 2.76 (95% CI 1.76–4.32) for second, third, and fourth quartiles, respectively, compared with the lowest quartile. This ecologic study confirmed the suspected association between incidence of acute encephalitis and litchi plantations and should be followed by other studies to identify the causative agent for this syndrome.