The latest figures from Brazil’s Health Ministry show a further rise in the number of babies born with microcephaly, a rare brain defect that causes abnormally small heads in newborns.
Microcephaly, thought to be a side effect of the Zika virus caught by expectant mothers, is believed to have affected 3,893 newborn babies since authorities began investigating the surge in October, officials said Wednesday.
Initial estimates released by Brazil’s Health Ministry last week reported 3,500 cases of the virus, which can cause severe developmental issues, brain damage and sometimes death.
In 2014, Brazil recorded fewer than 150 cases of microcephaly. Officials are convinced that the sudden jump is linked to an outbreak of the Zika virus, a mosquito-borne disease similar to dengue, though the mechanics of how the virus might affect babies remains unclear.
The ministry’s emergency response official, Wanderson Oliveira, said at a news conference in Brasilia Wednesday that the reported cases are being investigated to establish whether they are really cases of microcephaly. He stressed that the situation is very much in flux and “will change every day.”
The Fiocruz biomedical center in Curitiba announced Tuesday it had found Zika in the placenta of a woman who had a miscarriage, proving the virus can reach the fetus. Until now, researchers had only found Zika in the amniotic fluid of two pregnant women.
"This is a significant advance, but we still cannot scientifically state that Zika is the cause of microcephaly," said Jean Peron, an immunology expert who is experimenting on pregnant mice at the University of Sao Paulo's Institute of Biomedical Sciences.
At the moment, the only method to combat the Zika virus, which is spread by the Aedes aegypti mosquito, is to clear bodies of stagnant water.
Last week, Brazil’s Health Ministry said it had developed new testing kits to quickly identify the presence of dengue, Zika and Chikungunya viruses, which are all carried by the same species of mosquito, with priority testing to be given to pregnant women.
Funds have also been allocated to finance a bio-medical research center to speed up the search for a Zika vaccine.
teleSUR reported Wednesday that over 13,5000 cases of the mosquito-transmitted Zika virus have been detected in Colombia, a number that could rise to 700,000, with health experts warning the epidemic may spread across Latin America.
In adults, the viral disease usually causes a mild fever, rash, headaches, arthralgia, myalgia, asthenia and non-purulent conjunctivitis, with one out of four people affected not developing any symptoms at all, according to the World Health Organization (WHO).
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