Reason for increase in microcephaly cases in Brazilian infants unknown

Brazilian officials reported an unusual increase in the number of cases of microcephaly, a rare neurological condition, among infants in the country’s northeastern region, according to a WHO news release.

The Brazilian Ministry of Health notified the Pan American Health Organization (PAHO) and WHO of the increased incidence in October. As of Nov. 17, there were 399 cases under investigation in seven states. Officials said the majority of cases are in Pernambuco (n = 268), while there occurrences in Sergipe, Rio Grande do Norte, Paraiba, Piaui, Ceara and Bahia.

According to the release, microcephaly is a condition that affects newborns, in which the occipitofrontal circumference is smaller than average. The condition is diagnosed in children with a head circumference of two standard deviations below the mean compared with similarly aged children. Microcephaly is caused by genetic and environmental factors, leading to developmental problems. The condition is untreatable, the release said; however, early detection can boost quality of life.

Officials are investigating the cause, but have yet to determine epidemiology of the outbreak. As a result, Brazil has declared this a national public health emergency in hopes that awareness will help to identify any unknown cases. The Brazilian Ministry of Health is conducting clinical, laboratory and ultrasound analyses of infants and mothers.

PAHO and WHO recommend notification of any increase in microcephaly cases among its member states.