Microcephaly epidemic in Brazil: An earlier chapter.

Area of Science:

• Epidemiology
• Virology
• Public Health

Background:

• Microcephaly is a serious congenital condition with significant public health implications.
• Understanding the emergence and spread of microcephaly epidemics is crucial for timely intervention.
• Arboviruses, such as Zika virus, have been implicated in microcephaly outbreaks.

Purpose of the Study:

• To identify risk factors associated with microcephaly.
• To analyze historical trends of microcephaly and arboviruses to detect epidemic patterns.
• To pinpoint the onset of the microcephaly epidemic linked to Zika virus infection.

Main Methods:

• Analysis of head circumference data from 62,298 newborns (2014-2017) to identify microcephaly cases.
• Comparative analysis of risk factors between newborns with normal head circumference and microcephaly.
• Time series analysis of microcephaly incidence and dengue fever data to detect anomalous trends and potential new arbovirus circulation.

Main Results:

• Premature newborns, mothers under 20, and births in 2014-2015 were associated with higher microcephaly risk.
• Anomalous microcephaly incidences were detected in 2014 and 2015.
• Dengue fever epidemic data from 2013 indicated persistent high incidences in atypical periods, suggesting new arbovirus introduction.

Conclusions:

• Epidemiological evidence suggests Zika virus circulation occurred between Q2 2013 and early 2014.
• These findings contribute to understanding the Zika virus epidemic in the Americas.
• Early detection of arbovirus circulation through epidemiological surveillance is vital for public health preparedness.