Microcephaly, and the disorder's possible relationship to the Zika virus, explained

On Monday, director general of the World Health Organization Dr. Margaret Chan declared the mosquito-borne Zika virus to be an international public health emergency. Chan made a particular point of expressing the WHO’s concerns that the virus might be linked to a marked uptick in cases of microcephaly.

“In assessing the level of threat, the [WHO’s] eighteen experts and advisors looked in particular at the strong association in time and space between infection with the Zika virus and a rise in detected cases of congenital malformations and neurological complications,” Chan explained. “The experts agree that a causal relationship between the Zika infection during pregnancy and microcephaly is strongly suspected.”

Cases of the virus, which has been most commonly observed throughout equatorial areas of Africa and Asia in the past, spiked in Brazil in May of last year. Since then, over 1 million infections have been confirmed by Brazilian public health officials in addition to nearly 4,000 new instances of infant microcephaly.

More recently, Zika was identified as having made it into North America in a case of one person in Texas passing it to another through sex, confirming concerns that the virus would, in fact, spread beyond South America.

As more and more cases of the of infection are reported, public health officials in affected countries are asking women not to become pregnant in hopes of limiting the potential risk of spreading the virus.

To look at the coverage of the Brazillian Zika outbreak, one could easily walk away with the impression that once a person contracts the virus, they’re destined to develop microcephaly. That is not the case. The medical community is not concerned that Zika is necessarily causing microcephaly.

But doctors are concerned that the number of reported Zika virus diagnoses is keeping pace with the number of infants being born with microcephaly. As we all know by now, correlation does not imply causation, but it’s definitely the sort of data point that would prompt researchers to look into the events.

So when we talk about what makes the Zika virus so scary, we’re actually talking about microcephaly. While microcephaly could be caused by the Zika virus, it’s also important to remember that they aren’t the same thing and that right now, there’s no proven relationship between the virus and the condition (doctors are researching, but nothing definitive yet.)

Most people that contract Zika virus as adults liken it to a mild case of dengue fever with itchy rashes, joint pain, and conjunctivitis that clears up in a few weeks. Microcephaly, on the other hand, is a completely different medical condition that we would all benefit from knowing more about.

I spoke with Belsie González from the Centers for Disease Control about what the public should know about microcephaly.

What is it exactly?

“Congenital microcephaly is often a sign of the brain not developing normally during pregnancy,” González told me via e-mail. “Babies with microcephaly can have a range of other health problems, depending on the severity of their microcephaly.”

How common is it?

Not very. According to the CDC, microcephaly occurs somewhere between 2-12 babies per 10,000 live births here in the U.S.

How do you catch it?

You can’t “catch” microcephaly because it’s a disease that one is born with. If you don’t have it now, you’re never going to.

What are the symptoms?

When people think of microcephaly, they tend to picture people whose faces are abnormally small in comparison to size of their skulls.

While this is one of the condition’s most recognizable traits, González explained that the condition can also cause a number of other serious health complications like seizures, intellectual disabilities, and problems with movement and balance.

“These problems can range from mild to severe and are often lifelong,” González said. “In some cases, these problems can be life-threatening.”

How is it treated?

Currently, there is no cure for microcephaly and because of the various ways that it manifests itself in people, treatments take on many different forms. The earliest form of care that González recommended was regular pre- and post-natal checkups with a pediatrician.

“Because it is difficult to predict at birth what problems a baby will have from microcephaly, babies with microcephaly often need close follow-up through regular check-ups with a healthcare provider to monitor their growth and development,” González said.