DHAKA: New figures from Brazil show a further rise in the number of babies born with abnormally small heads to mothers infected with the Zika virus.
There have been 3,893 cases of microcephaly since October, when the authorities first noticed a surge, up from 3,500 in last week's report.
Zika is transmitted by the bite of the Aedes aegypti mosquito, which also spreads dengue and chikungunya, reports the BBC.
Brazil is experiencing the largest known outbreak of Zika.
The Zika virus has already killed five babies in the country, said the Health Ministry. Another 44 cases are being investigated.
Last week, Health Minister Marcelo Castro said a new testing kit was being developed to identify quickly the presence of either of the three viruses.
He also announced extra funds to speed the development of a vaccine for Zika "in record time".
At the moment the only way to fight Zika is to clear standing water where mosquitoes breed.
The US Centers for Disease Control and Prevention issued an alert last Friday advising pregnant women to avoid travelling to Brazil and other Latin American and Caribbean countries where outbreaks of Zika have been registered.
The travel alert applies to Brazil, Colombia, El Salvador, French Guiana, Guatemala, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Suriname, Venezuela and Puerto Rico.
BDST: 1420 HRS, JAN 21, 2016
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