The World Health Organization will convene an emergency committee meeting on Monday to discuss the Zika virus, a condition that is “spreading explosively” throughout the Americas, according to the WHO’s director general, Margaret Chan. Health officials at the meeting will decide if the recent outbreak of the virus — which has been tentatively linked with a rise in birth defects — constitutes an international public health emergency.
More specifically, the purpose of the meeting is to determine what measures the WHO should take as well as the advice the organization should give to affected countries. The meeting will also establish how to proceed with researching the virus, which has now been detected in 23 countries in the Americas.
“The level of alarm is extremely high, as is the level of uncertainty. Questions abound. We need to get some answers quickly, ” Chan said at a briefing today in Geneva, outlining four reasons why health officials are so concerned:
“First, the possible association of infection with birth malformations and neurological syndromes. Second, the potential for further international spread given the wide geographical distribution of the mosquito vector. Third, the lack of population immunity in newly affected areas. Fourth, the absence of vaccines.”
Taken together, these factors have “rapidly changed the risk profile of Zika from a mild threat to one of alarming proportions,” Chan said.
Zika virus is an illness spread primarily by the Aedes aegypti mosquito, though there’s also evidence from a few small studies that people infected with Zika can transmit the virus to others through sexual intercourse. Zika can also be transmitted through contaminated blood, and mother-to-fetus transmission has been documented throughout pregnancy.
Around 80 percent of those infected with Zika don’t experience symptoms. For the 20 percent who do, the condition is usually pretty mild, causing fever, rashes, joint pain, and conjunctivitis, according to the U.S. Centers for Disease Control and Prevention. But recently, experts have been concerned that the Zika virus may be causing far more serious and lasting health effects in newborn children.
The virus first arrived in Brazil in May of 2015, and since then, as many as 1.5 million people have been infected. The outbreak has coincided with a steep increase in children being born with abnormally small heads, a condition called microcephaly. Around 4,180 children have been born with the defect in Brazil since October 7th. At the same time, Brazil has also seen a worrisome increase in Guillain-Barré syndrome — a condition that can lead to partial paralysis. No causal relationship has been established between the Zika virus and these health issues, but health officials strongly suspect a link. The CDC is conducting a study in Brazil to see if the conditions are connected.
The Zika virus has since spread rapidly beyond Brazil into at least 22 surrounding countries and territories. So far, only 20 or so cases have been recorded in the United States. These cases were identified in travelers; no locally transmitted cases have been reported in the continental United States so far. That has prompted the CDC to issue travel alerts for the countries in which the disease is ongoing, recently adding the United States Virgin Islands and Dominican Republic to the list. The CDC has also advised that pregnant women or women who are trying to get pregnant postpone traveling to these areas.
Although Zika transmission has not yet been reported in the United States, mosquitoes that carry the infection are endemic to specific regions of the country, and experts believe local transmission is likely in the coming months as the weather heats up. One WHO scientist estimated that there could be up to 4 million Zika infections in the Americas over the next year. And like so many other infectious diseases, experts say climate change is likely a key factor in its spread.