How Dangerous Is Zika? A Q&A

The Aedes aegypti mosquito carries the Zika virus.

The Aedes aegypti mosquito carries the Zika virus.

A rare tropical disease known as the Zika virus has spread to 24 countries and territories, mostly in the Caribbean and Latin America. Infection with the virus appears to be linked to brain damage and unusually small heads in newborns, which has prompted the Centers for Disease Control and Prevention (CDC) to warn pregnant women against travelling to affected countries. Now the virus is creeping into North America with approximately 20 cases in the continental U.S., including three in New York City. Here are some questions and answers about Zika and what precautions the city and state are taking to protect the public.

What is the Zika virus?

The Zika virus is a mosquito-transmitted disease that is related to dengue, yellow fever, and West Nile virus. Discovered in Uganda in 1947, the virus was named after the forest it was found in and is common in parts of Africa and Asia. It wasn’t until an outbreak in May that the virus began to spread widely in the Western Hemisphere.

What are the symptoms?

One in five people infected with Zika will become sick, according to the CDC. For those who do become ill, the most common symptoms are fever, rash, joint pain, and puffy, red eyes. But the biggest cause for concern is that Zika may cause microcephaly—a birth defect that causes abnormally small heads and brain damage. The possibility emerged late last year when doctors in Brazil noticed a surge in babies with the condition. In 2014, fewer than 150 cases of microcephaly were reported in Brazil, but since last Oct. more than 4,000 cases have been recorded in the country.

How is the virus spread?

The mosquito responsible for the spread, Aedes aegypti, bites during the day and is fond of dirty, urban areas where there is plenty of standing water for breeding grounds, according to Dr. David Morens of the National Institute of Allergy and Infectious Diseases. This mosquito is common in the U.S. only in Hawaii and along the Gulf Coast, but the Asian tiger mosquito, Aedes albopictus, is also known to transmit the virus and is found in at least 32 states in the U.S.

The virus is typically spread by mosquitos, but according to the World Health Organization (WHO) there has been one infection through a blood transfusion. To combat this, the U.S. said it will block those who have visited regions impacted by the virus from donating blood. There has also been a report of a possible transmission through sexual contact, according to the WHO. Dr. Morens said it is typical for a handful of cases in which the virus’s transmission deviates from its typical means of infection.

Why is it spreading now?

Although the Zika virus has been around for nearly seven decades, it has garnered less attention from the WHO because its symptoms are relatively mild compared to other diseases and it wasn’t until recently that Zika was linked to birth defects.

In 2007, a Southeast Asian strain of the virus began jumping across the South Pacific. This led to outbreaks on islands where residents had little to no immunity to Zika. Since then, the virus has spread rapidly to places where people lack the immune defense and are susceptible.

Is there a treatment? A vaccine?

There is no vaccine in advanced development to prevent Zika infection and there is no specific medicine to treat the Zika virus once a person is infected. But scientists are optimistic that vaccines made for similar diseases can be adapted. “It’s like if we baked a cake and if we want to make it chocolate we just have to add the flavor, the ingredients are already there,” explained Dr. Morens.

Are New Yorkers at risk?

At present, the risk of becoming infected with Zika in New York is very low because mosquitos are not active during the winter months.

What preventive measures is the New York State Department of Health taking?

The NYS Department of Health is closely watching the state’s mosquito population. Once warmer weather arrives, the department will monitor areas where the Aedes albopictus mosquito is found and preform tests to identify if the Zika virus is present. Other mosquito species that were collected and tested for West Nile virus and Eastern Equine Encephalitis in past years will also be tested for the Zika virus.

How would New York City respond if the Zika virus is found locally?

If local mosquitos began infecting New Yorkers come spring, the Department of Health and Mental Hygiene said it would employ methods used to prevent West Nile. One of those methods includes city-wide aerial sprays of pesticides to curb mosquito spawning.  Another is larvacide, in which standing water that houses mosquito larve is disposed of before they have a chance to emerge.

What are city health officials doing to educate New Yorkers about the Zika virus?

The Department of Health and Mental Hygiene is working with the CDC to issue alerts that better inform health care providers when checking for symptoms in patients. It is developing a public awareness campaign, has issued a travel warning for pregnant women in nine languages, and is conducting outreach to women’s health providers including OB/GYN, pediatrics, and family medicine facilities. Public health officials are also meeting with health experts in Southern States and the Caribbean to learn from their existing plans.