Brazilian authorities have reported a huge increase in the number of babies born in the country with uncommonly small heads, and suspect that the surge is linked to an outbreak of the mosquito-borne Zika virus.
According to the BBC, in 2014, only 150 Brazilian babies were born with the cranial birth defect known as microcephaly; since October alone, however, authorities have reported 3,893 new suspected cases. Some 90% of these cases have been recorded in Brazil's northeastern states, where the country's Zika outbreak — the largest on record — is most pervasive, the BBC says.
Brazil's Health Ministry added that of the 49 babies born with suspected microcephaly who have died, five were infected with Zika.
Patients with microcephaly have notably smaller heads and several associated health issues — typically limited brain function and a diminished life expectancy.
The virus is spread by the mosquito that also transmits dengue fever, and is typically seen as mild, with symptoms appearing in only one of five people exposed to it.