What’s the Link between Zika Virus and Hearing Loss?
Updated – originally published March 23, 2016
Brazil first notified the World Health Organization (WHO) of samples testing positive for the Zika virus in April, 2015.
Fast forward to 2016 and the US Centers for Disease Control and Prevention (CDC) has confirmed the link between babies being born with microcephaly and the Zika virus, which their mothers contracted primarily from Aedes mosquitoes.
Urged to limit travel
When the news of Zika began to spread globally, people were being advised to limit or avoid travel to Brazil, particularly if they were pregnant. The Brazilian government was urging its population to avoid or delay getting pregnant in an effort to curb the number of children being born with microcephaly.
By February 1, 2016, the WHO declared Zika virus and the instance of microcephaly in babies a “public health emergency of international concern.”
The evidence is in
Now the CDC says the evidence is in and is enough to say with certainty that Zika causes the birth defects doctors have been seeing in babies, mainly in Brazil.
The CDC’s Director, Dr. Tom Frieden now says, “there is no longer any doubt that Zika causes microcephaly.” Dr. Frieden also says that Zika contributes to other serious defects including the build-up of calcium in the brain.
Zika virus’ link to hearing loss
Hearing loss has long been cited as one of the many conditions that affects children born with microcephaly, which is most notably characterized by a smaller than normal head.
Delayed development and vision problems are among the medical issues facing infants with microcephaly, which range from mild to severe.
According to Dr. Viviane Boaventura, a Brazilian Ear, Nose and Throat doctor, 10 of her patients with the Zika virus had been exhibiting symptoms like vertigo, dizziness, tinnitus and hearing loss.
Up to two months after contracting the virus, her patients were still experiencing “measurable and significant hearing loss, as well as light-headedness.”
Currently, the Zika virus has no cure or vaccine. No one knows if contracting Zika will have any long-term impact on the health of the people who contract it.
Recent study on Zika and microcephaly
Recently, a retrospective study published in The Lancet looked at babies born with microcephaly around the time of a Zika virus outbreak in French Polynesia from October, 2013 to April, 2014.
Sixty-six percent of the population contracted Zika. Eight cases of microcephaly were identified. The study also found that there appeared to be a higher risk of microcephaly during a Zika-infected woman’s first trimester.
The study points to a possible 1% risk of brain defects in babies. That’s a number that could pose a serious threat in a large population. French Polynesia’s population is just over 276,000.
Research continues
At the University of Glasgow researchers are working on developing a rapid test for the Zika virus.
Recent findings show that babies with microcephaly from Zika infected mothers have traces of the virus in their brain tissue, spinal fluid and amniotic fluid. These findings helped confirm the link between Zika and microcephaly in infants.
The US Senate recently approved a bill to speed up the development of a cure for the mosquito-borne illness. Drug companies are scrambling to find a vaccine for the virus that scientists isolated in 1947 in Uganda.
Only time and research will tell whether there are any long-term health effects of the Zika virus for those who contract it, what they are and if they include long-term hearing loss problems?
