WASHINGTON — Panama has reported its first case of birth defects associated with the Zika virus, the World Health Organization said on Tuesday — new evidence of the epidemic’s potentially dangerous effects spreading throughout the region.
Dr. Margaret Chan, the director general of W.H.O., said a baby with an unusually small head and brain damage — a condition called microcephaly — was born at 30 weeks’ gestation in Panama and died a few hours later. Local investigators found evidence of the Zika virus in the umbilical cord.
Dr. Chan was providing an update on the Zika virus and its spread in the Americas.
Scientists around the world are waiting to see whether more pregnant women who become infected eventually give birth to babies with microcephaly.
“The knowledge base is building very rapidly,” Dr. Chan said. “The more we know, the worse things look.”
So far, a surge of cases has been documented only in Brazil. In most other countries where Zika infections have spread, pregnant women who might have been exposed have yet to give birth.
The virus is circulating in 38 countries and territories, Dr. Chan said.
“No one can predict whether the virus will spread to other parts of the world,” she added.
Brazil and Panama are the only countries that have documented microcephaly cases linked to Zika infection from mosquito bites, Dr. Chan said, but Colombia is investigating several cases with a possible connection.
Officials have said that if there is a link, as most scientists believe, they expect to start seeing birth defects in Colombia in June.
Dr. Chan said Colombia had set up “a very robust mechanism” to determine whether microcephaly in newborns there was linked to Zika infection.
Cape Verde, a small nation of islands off the coast of Senegal, reported a case of suspected microcephaly last week, and Dr. Chan said W.H.O. has sent investigators to help analyze it. The team includes epidemiologists, laboratory experts, maternal health specialists and communication staff members.
W.H.O. said last week that there had been 7,490 suspected cases of infection with the Zika virus reported in Cape Verde from Oct. 21 to March 6, and that 165 were in pregnant women. Officials said 44 women had given birth without any abnormalities.
In Brazil, the numbers still lack clarity.
Dr. Anthony Costello, the director of the maternal, newborn, child and adolescent health department at W.H.O., estimated that 39 percent of the approximately 2,200 suspected microcephaly cases that were carefully investigated, including with brain scans, were eventually confirmed.
Using that ratio and the current count of about 6,500 suspected cases, Dr. Costello said he would expect a total of about 2,500 confirmed cases.
“Given the rapid spread of this,” he added, “we must expect that burden to increase substantially.”
Dr. Chan said funding to address the Zika outbreak had been slow in coming. The organization has received about $3 million out of a requested $25 million, and officials are in “active discussion” over $4 million more.
“The situation is still pretty serious in terms of lack of funding,” she said.