[Mumps transmission control status and inapparent infection rate among middle and high school students during the 2007-2008 mumps outbreak in Daegu].
OBJECTIVE
This study was performed to investigate the mumps transmission control status and inapparent infection rate among middle and high school students in Daegu City during a mumps outbreak.


METHODS
Nine schools (two middle schools and seven high schools), which reported a number of mumps cases between 2007 and 2008 were selected for investigation. During March-May 2008, a standard questionnaire was distributed to gather information about case identification, instructed isolation measure, isolation status of mumps cases and related factors, and outdoor activities of non-isolated mumps case. Inapparent infection rate was estimated by serum mumps IgM and IgG antibodies status and self-reported mumps symptoms in three of the nine schools.


RESULTS
Among 2,560 respondents, more than half of students answered that they did not receive instructions in mumps transmission control measures during the outbreak. Among the 327 mumps cases identified by the questionnaire, 131 cases (40.1%) were considered as isolated and the isolation rates were significantly different among schools, grades, and gender. Of the non-isolated cases, 88.3% continued attending school. Inapparent mumps infection rates were between 56.3% and 70.2%.


CONCLUSIONS
Mumps transmission control was inadequate to control the mumps outbreak. Although high inapparent infection rate would mitigate the transmission control effect of case isolation, this measure is fundamental for infection control. The reasons of this inadequate status need to be explored to develop an effective intervention strategy.
Kim
Kyo Hyun
KH
Department of Preventive Medicine, Eulji University School of Medicine, Korea.
Kim
Chang Hwi
CH
Choi
Bo Youl
BY
Go
Un Yeong
UY
Lee
Dong Han
DH
Ki
Moran
M
D000293:Adolescent; D002648:Child; D003140:Communicable Disease Control / Q000379:methods*; D004196:Disease Outbreaks / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008297:Male; D009107:Mumps / Q000453:epidemiology / Q000517:prevention & control* / Q000635:transmission; D010356:Patient Isolation; D056910:Republic of Korea / Q000453:epidemiology; D012574:Schools / Q000706:statistics & numerical data*; D013334:Students; D011795:Surveys and Questionnaires
D007074:Immunoglobulin G; D007075:Immunoglobulin M