OUTBREAK OF MEASLES IN THE REPUBLIC OF KOREA, 2007: IMPORTANCE OF NOSOCOMIAL TRANSMISSION

Monday, 31st of March 2014

[source]Journal of Infectious Diseases[|source]

The Republic of Korea (ROK) launched a Five-Year Measles Elimination Program in 2001. By 2006, ROK was the first country in the World Health Organization (WHO) Western Pacific Region to declare measles eliminated. In 2007, 180 of 451 suspected measles cases reported to the Korea Centers for Disease Control and Prevention (KCDC) were confirmed as measles. Approximately one-half of confirmed case patients were infected through nosocomial transmission.

 In this report, the authors describe the measles outbreak and review aspects of measles virus transmission in ROK. The authors argue that measles outbreaks of limited duration may occur even after countries have achieved measles elimination before concluding that nosocomial transmission can play an important role in such outbreaks.  More details and recommendations are accessible at: http://jid.oxfordjournals.org/content/204/suppl_1/S483.long

 

ABSTRACT

BACKGROUND: From 2002 through 2006, Republic of Korea conducted extensive measles elimination activities and declared elimination in 2006. An outbreak of measles involving 180 confirmed cases occurred during 2007.

METHODS: An outbreak investigation was performed and enhanced surveillance was implemented. Detailed case investigations and laboratory testing included serologic and molecular diagnostic methods. Cases were classified according to World Health Organization and national guidelines.

RESULTS: During 2007, 451 suspected cases were reported and 180 (40%) cases were confirmed as measles during epidemiologic weeks 14–42. Incidence during the outbreak was 3.7 cases per million persons, excluding imported cases. Most confirmed cases were reported from Seoul; 137 (76%) cases were among children <24 months old, 124 (69%) case patients had no history of measles vaccination, and 81 (45%) case patients resulted from nosocomial transmission in 6 hospitals. Community members, patients, and health care workers all contributed to measles virus transmission. Limited outbreak control measures were implemented; high population immunity likely accounted for the self-limited transmission during this outbreak.

CONCLUSIONS: Limited outbreaks of measles, in which nosocomial transmission can play an important role, may occur after countries have declared elimination. Timely and opportunistic vaccination may help prevent such outbreaks; high-quality surveillance is critical for their detection.