Zika-related microcephaly cases reach five in Colombia

Five infants have been born with Zika-related microcephaly in Colombia since officials began monitoring the outbreak of the mosquito-borne virus, the country's health authorities said Saturday.

The first two Zika-related cases of microcephaly -- infants born with abnormally small heads and brains -- were reported in mid-April, and three more were reported Saturday in a National Institute of Health (INS) bulletin.

Health officials have said they estimate some 300 infants expected to be born between May and September will have Zika-related microcephaly, given the number of infected pregnant women who have not yet given birth.

The virus has infected nearly 84,000 people since officials began monitoring the outbreak in October. Nevertheless they said in the bulletin that the number of cases is declining.

Since October, there have been 6,400 confirmed cases of Zika infection and another 77,500 suspected cases. The total of both groups include 15,038 pregnant women.

Since December there have also been 529 cases of neurological disorder -- mainly Guillain-Barre Syndrome -- with symptoms similar to Zika, which specialists are still studying.

The health ministry said in December that the average number of infants born with microcephaly in Colombia (population 48 million) each year before the Zika outbreak was 129.

The Zika virus usually triggers only mild, flu-like symptoms. It is mainly spread by two species of Aedes mosquito, but has also been shown to transmit through sexual contact.

There is no vaccine to prevent Zika.