Resurgence of measles in Singapore: profile of hospital cases.
OBJECTIVE
To ascertain the profile of cases of measles seen at a general hospital during a recent outbreak that occurred despite a measles vaccination program.


METHODS
A retrospective study from January 1991 to March 1998. All patients with measles (ICD code 055. 9) seen at the emergency unit or as inpatients were included.


RESULTS
There were 87 cases identified. The diagnosis was clinical in all and proven serologically in 71%. Eighty-five per cent of the cases occurred between January 1997 and March 1998. There was a bi-modal age distribution with peaks in the very young (</= 18 months) and those aged 16-20 years. The majority was unvaccinated (58/87). A proportion (11/87) demonstrated vaccine failure, most likely primary failures.


CONCLUSIONS
This changing measles epidemiology suggests lowering of herd immunity. 'Catch up' vaccinations in July- October 1997 given to school children aged 12-18 years (200 000 individuals or 82% of cohort), may have helped contain the outbreak. These results substantiated the need for a two-dose policy and 'catch-up' immunization program.
Goh
D
D
Department of Paediatrics, National University of Singapore.
Chew
F
F
Khor
S
S
Lee
B
B
D000293:Adolescent; D000328:Adult; D002648:Child; D004196:Disease Outbreaks; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D007223:Infant; D007902:Length of Stay; D008297:Male; D008457:Measles / Q000453:epidemiology* / Q000517:prevention & control / Q000534:rehabilitation*; D008458:Measles Vaccine / Q000627:therapeutic use; D012189:Retrospective Studies; D012846:Singapore / Q000453:epidemiology
D008458:Measles Vaccine