Challenges posed by changes in measles transmission patterns.

OBJECTIVE

To quantify changes in measles transmission patterns.

DESIGN

Analysis of measles surveillance data.

SUBJECTS

All measles cases identified in 1988.

MAIN OUTCOME MEASURES

Proportion of cases in age group 60 to 119 months, proportions of vaccinated and unvaccinated cases in age group 60 to 119 months, and occurrence of cases in schools.

RESULTS

Measles vaccination coverage was 91%. Incidence rate of measles was 205 per 100,000 population. The age group 60 to 119 months accounted for 49% of all reported cases and 68% of cases in this age group were vaccinated. There were measles epidemics in schools and these were associated with occurrence of secondary cases in younger siblings in the community. Case fatality rate and mortality rate were 0.4% and one per 100,000 population respectively.

CONCLUSION

High measles transmission in children of school going age could spill into the community through generation of secondary cases among younger siblings and this could result in high morbidity and mortality in this vulnerable group. It is recommended that either revaccination at school entry or mass vaccination campaigns be carried out in affected age groups at schools to reduce occurrence of epidemics.