The Zika virus, which has been linked to microcephaly, is spreading quickly around the world. Originally limited to areas in South America, primarily Brazil, it is now being diagnosed in other areas of the world. The Center for Disease Control and Prevention has confirmed the birth of a microcephalic baby in Hawaii whose mother was infected with Zika during her pregnancy.
Current estimates show that, in 2015 alone, more than one million people in Brazil have had Zika virus infection. The virus is most commonly spread from person to person by way of the Aedes aegypti mosquito. For most people who become infected the symptoms will only include a short fever, skin rash, and joint pain. In some cases, conjunctivitis, muscle pain, and headaches have been observed, and in rare situations, patients experience so symptoms at all. Very rarely does the viral infection turn fatal.
However, pregnant women that become infected are at much higher risk than others. The virus has been linked to the development of microcephaly in unborn children. Within 6 months of the initial outbreak of the virus, the rate of newborn babies diagnosed with the condition was 2000% of the norm. In 2015 alone, more than 3100 microcephalic children were born.
New research published in JAMA Ophthalmology indicates that microcephaly may not be the only health risk posed to babies. When observing 29 babies with Zika virus related microcephaly, 10 of them had vision-threatening lesions on their eyes.
Due to the areas in which the virus is spreading fastest, it's impossible to know the exact number of people that have been infected so far, but it's estimated to be in the millions. Poor South American communities can't afford the testing equipment, and few people are trained in the methods needed to do so. Even in developed countries like the USA, where the Center for Disease Control and Prevention can perform serologic testing, those infected with the virus have such mild symptoms that they are very likely to go completely undetected.
Faced with the effects the Zika virus has on babies during the first and second trimesters of the pregnancy, it's been recommended that women living within the bounds of the epidemic avoid getting pregnant, and that those living outside the area that are already pregnant not travel into the affected areas.