RIO DE JANEIRO/BOGOTA – The Zika virus, believed to be linked to the serious birth defect microcephaly, presents a “formidable” challenge that will be hard to stamp out, World Health Organization chief Margaret Chan said Wednesday.
“Things could get worse before it gets better,” she said in Rio de Janeiro after a fact-finding mission to Brazil, the epicenter of the global health scare.
Chan said part of the challenge in fighting the mosquito-borne virus was the fact that it is so “mysterious.” Even the link to microcephaly remains not fully proven.
“We are dealing with a tricky virus, full of uncertainties, so we should be prepared for surprises,” she said.
Chan praised the Brazilian government’s efforts to stamp out mosquitoes and its coordination with various international bodies, including the WHO and the International Olympic Movement, ahead of the Summer Games in Rio this August.
Brazil is the main focus of a Zika outbreak, with 1.5 million people infected, and authorities have also recorded a spike in microcephaly, a congenital condition that causes abnormally small heads and hampers brain development.
On Tuesday, Brazil’s health ministry reported 583 confirmed cases of babies with microcephaly since October, compared to an annual average of 150.
That was a 14.7 percent rise over the number of confirmed cases the previous week, and authorities were investigating another 4,107 possible cases.
An estimated 120 babies have died due to the birth defect, the ministry said.
Colombian health officials meanwhile reported on Wednesday a “probable” case of microcephaly possibly linked to Zika, as the country closely watches potential impacts of the mosquito-borne virus.
The country’s National Health Institute said Zika virus was identified in the amniotic fluid surrounding a severely deformed and aborted fetus.
The abortion was performed on an 18-year-old mother when she was 28 weeks pregnant. Photographs were not taken of the fetus, but the doctor in Popayan, in the southwestern region of Cauca, had reported the fetus having an abnormally small head and considered it microcephaly, the institute, known as INS, said.
Zika infection in pregnant women has not been proven to cause microcephaly in newborns.
In Brazil, a huge spike in the birth defect followed the arrival of Zika last year, leading scientists to strongly suspect a link. Colombia has had its own Zika outbreak since October, and is monitoring pregnant women exposed to the virus, but has yet to cite a case of microcephaly.
The Popayan case cannot be confirmed as microcephaly since the remains of the fetus were thrown away immediately after the abortion and tests could not be made, INS said. Traces of Zika were detected in the amniotic fluid, it said.
“Unfortunately in this case, the breach of guidelines by those responsible for handling the case in Cauca prevented an accurate diagnosis being reached,” Martha Lucia Ospina, director of the INS, said in a statement.
“They discarded the fetal remains that were indispensable to diagnose or rule out Zika and the link with microcephaly and other abnormalities.”
Brazil said it has confirmed more than 580 cases of microcephaly, and considers most of them to be related to Zika infections in the mothers. The country is investigating more than 4,100 additional suspected cases of microcephaly.
Colombia — which has reported more than 37,000 cases of Zika including 6,356 in pregnant women — is seen as a key test case for the impacts of a Zika outbreak.
The health minister last week said Colombia is reconsidering its own forecast of babies likely to be born with the rare birth defect linked to Zika.
The government originally projected it could see some 500 to 600 cases of Zika-linked microcephaly. But it may take several more weeks, or months, for cases to emerge as signs of microcephaly may only be detected very late in pregnancy, experts say.
There is no vaccine or treatment for Zika, which is a close cousin of dengue and chikungunya and causes mild fever, rash and red eyes. An estimated 80 percent of people infected have no symptoms.