Zika has Arrived in the United States

On Friday, the Centers for Disease Control and Prevention (CDC) announced that they had been informed by the State of Florida that Zika virus infections in four people caused by bites of local Aedes aegypti mosquitoes. These cases are the first known occurrence of local mosquito-borne Zika virus transmission in the continental United States.

According to Tom Frieden, M.D., MPH., director of the CDC. “All the evidence we have seen indicates that this is mosquito-borne transmission that occurred several weeks ago in several blocks in Miami, We anticipate that there may be additional cases of ‘homegrown’ Zika in the coming weeks. Our top priority is to protect pregnant women from the potentially devastating harm caused by Zika.”

The disease symptoms which include fever, rash, joint pain, myalgia, headache, pain behind the eyes and conjunctivitis (pink eye) are usually mild and last for 2 to 7 days. Infection may go unrecognized or are misdiagnosed as dengue, chikungunya or other viral infections that cause fever and rash. Many do not even know they have Zika, according to the CDC only 20% of people infected with Zika virus will develop symptoms, so there may be many more cases in Florida.

The concern of course is the possible association of Zika Virus with a serious birth defect, microcephaly, babies born with abnormally underdeveloped heads, and other poor pregnancy outcomes in babies of mothers who were infected with Zika virus while pregnant. In addition to an observed connection to other neurological disorders including Guillain-Barré Syndrome.

Here is what the CDC knows:

• Zika is spread to people primarily through the bite of an infected Aedes species mosquito (Ae. aegypti and Ae. albopictus). 
• A pregnant woman can pass Zika virus to her fetus during pregnancy or during birth.
• Zika virus infection can cause microcephaly and other severe fetal brain defects, and is associated with other adverse pregnancy outcomes.
• A person who is infected with Zika virus can pass it to sex partners.
• Many people infected with Zika virus won’t have symptoms or will only have mild symptoms.
• No vaccines or treatments are currently available to treat or prevent Zika infections. 

We are currently in mosquito season in the United States. Because the Aedes species mosquitoes that spreads the Zika virus are found throughout the United States in the related Asian Tiger mosquito that entered the United States from Asia in the mid-1980s. It can survive in a broad range of climates and has spread rapidly from the point of first detection in the south-central United States to the entire eastern and central U.S. and now California. Analysis of mosquitoes captured in a 2007 mosquito study in Africa identified the presence of the Zika virus in the Asian Tiger mosquito. Thus, this insect, known to be the vector of dengue and chikungunya, also can carry the Zika virus.

The good news for us is so far the winter die off in the more northern states has limited the populations of the mosquito and the diseases that the Asian Tiger mosquito can spread. Because we are in mosquito season, CDC encourages everyone, especially pregnant women and women planning to become pregnant, to protect themselves from mosquito bites. Use an insect repellent , wear long-sleeved shirts and long pants, use or repair screens on windows and doors, use air conditioning when available, and remove standing water where mosquitoes can lay eggs.