Prevalence of microcephaly in an Australian population-based birth defects register, 1980–2015
The known Microcephaly has recently received increased attention because it is associated with congenital Zika virus infection. The World Health Organization recommends that countries at risk of Zika virus transmission collate baseline data on the historical prevalence of microcephaly.
The new We report the prevalence and characteristics of microcephaly in a geographically defined Australian population over a 35-year period. Significant rate differences between Aboriginal and non-Aboriginal births were identified.
The implications Our study provides a useful baseline that will allow changes in microcephaly prevalence to be measured, and raises important matters for consideration by other jurisdictions reviewing their birth defects surveillance systems.
Microcephaly is a birth defect in which a child’s head is smaller than expected for their age, sex and ethnicity; there are, however, varying operational definitions of how much smaller (eg, head circumference below the first or third percentile, or more than two or three standard deviations below the mean value). The lack of a universally accepted definition complicates the comparison of prevalence estimates, which range from 2 to 12 per 10 000 live births in…