Officials from the Centres for Disease Control and Prevention (CDC) have confirmed that there are now 234 pregnant women in the continental US carrying the Zika virus – an infection spread by mosquito bites that can cause a devastating birth defect called microcephaly.

Out of these women, there have been six "abnormalities" – three babies born with birth defects so far, and another three who died before birth – though officials did not say how many of the women have given birth in total, and how many are still pregnant.

As Sabrina Tavernise from The New York Times points out, the report poses more questions than it gives answers. For example, without knowing the number of babies born, how do we make sense of the six abnormalities? Do these represent a large or small amount of the women infected?

In response to those questions, one of CDC's leaders on pregnancy and birth defects, Denise Jamieson, said that the newly released numbers are only the first in a series of updates that will provide more information.

"We're sort of in a hard place," Jamieson told The New York Times. "We can't provide a lot of information about where these women are in their pregnancy. We don't want to inadvertently disclose information about difficult decisions these women are making about their pregnancies."

The CDC also hasn't disclosed where any of these women were infected with the virus, or how they came in contact with it.

So far, we do know that one of the babies was born was microcephaly – a birth defect that causes a baby's brain to not fully develop during pregnancy, resulting them being born with an abnormally small head and cognitive complications.

Jamieson said that the risk of an infected woman giving birth to a child with birth defects is around one to 15 percent. "Microcephalic babies are beginning to be born [in the US]," Jamieson said. "The disease seems to be very similar no matter where it is."

Though Zika virus can cause major health problems for pregnant women and their unborn children, the infection is usually pretty harmless for most healthy individuals. In fact, roughly 80 percent of those infected never know it. Usually, even if symptoms, such as fever and rash, appear, they only last a few weeks and rarely end in hospital visits.

The virus was first discovered back in 1947 in monkeys, getting its name from the Zika Forest in Uganda where it was found. The first reported cases of Zika started to emerge in 1952 in Uganda and the United Republic of Tanzania.

"Before 2007, at least 14 cases of Zika had been documented, although other cases were likely to have occurred and were not reported," reports the CDC. "Because the symptoms of Zika are similar to those of many other diseases, many cases may not have been recognised."

The virus is primarily transmitted through mosquito bites, though men can sexually transmit the disease if they were recently infected before a sexual act. The CDC says that the best way to prevent contracting the illness is to avoid getting bitten in the first place, which is obviously easier said than done. To help with this, the CDC has a full list of prevention methods on their website.

"What we're seeing is a very consistent pattern underscoring the fact that Zika causes microcephaly and other severe brain abnormalities," Jamieson told Lena H. Sun from The Washington Post. "This highlights the importance of preventing unintended pregnancies, avoiding mosquito bites and for pregnant women to avoid traveling to areas with ongoing Zika virus transmission."

Despite all of this bad news, scientists are working hard to combat the disease, with several vaccine candidates in development. Back in May, an international team of researchers created a tool that can diagnose Zika in just a 3 hours. So far, though, an effective treatment for pregnant women has remained out of sight.