Hidden varicella outbreak, Luang Prabang Province, the Lao People's Democratic Republic, December 2014 to January 2015.

WPSAR Vol 7, No 1, 2016 | doi: 10.5365/wpsar.2015.6.2.010 www.wpro.who.int/wpsar 1 a National Center for Laboratory and Epidemiology, Ministry of Health, Vientiane Capital, the Lao People’s Democratic Republic. b Offi ce of the WHO Representative in the Lao People’s Democratic Republic, Vientiane Capital, the Lao People’s Democratic Republic. c Emerging Disease Surveillance and Response Unit, Division of Health Security and Emergencies, World Health Organization Regional Offi ce for the Western Pacifi c, Manila, Philippines. Submitted: 6 June 2015; Published: 12 January 2016 doi: 10.5365/wpsar.2015.6.2.010 Background: In January 2015, the Lao People’s Democratic Republic Ministry of Health received a report of 34 cases of fever and rash with one laboratory-confirmed measles case in Houitone village, Pakseng District of Luang Prabang Province. Between 21 and 27 January, we conducted a field investigation to determine the etiology, magnitude and severity of this outbreak.