Zika Virus - Congenital Zika Infection & Microcephaly
There has been an explosive rise in the number of cases of Zika virus infection with a nidus in Latin America and the Carribeans.
Zika virus is related to Dengue, West Nile and some other viruses. It was first noted in 1947 in Africa and has spread by outbreaks to many different countries, with an ongoing outbreak in Brazil (In May 2015, Zika virus infections first arose in Brazil). and Puerto Rico; it has also been diagnosed in Harris County (Houston) Texas in January of 2016.
The Virus is transmitted to people by a mosquito (Aedes) vector; and so the risk factor for infection is a mosquito bite. The means of infection for the US infection was via sexual contact and so the potential for transmission through sex has become an added concern. The incubation period for the virus is about three to twelve days after the bite by an infected mosquito.
The symptoms and signs of Zika virus are usually:
The virus infection is usually diagnosed by the patient’s history and physical exam and by blood testing (usually done in the CDC). Treatment is related to symptom control, and over the counter medications are used in most infected people. Rarely complications such as dehydration or neurologic problems may develop. Prognosis is good for Zika infection, however microcephaly can complicate Zika infection especially if a proven infection in pregnancy is noted and there is therefore a poor outcome for the child.
Epidemiologic evidence and amniotic fluid isolates testing from the brain and heart of an infant with microcephaly, in Brazil have linked an outbreak of Zika virus to development of congenital microcephaly.
Microcephaly is a condition where the head circumference is smaller than normal. It can be caused by genetic abnormalities or by drugs, alcohol, certain viruses and toxins that a fetus is exposed to in pregnancy. Signs and symptoms of microcephaly may include a smaller than normal head circumference that usually remains smaller than normal as the child grows, dwarfism or short stature, delayed motor speech functions, mental retardation, seizures, facial distortions, hyperactivity, balance and coordination problems, and other brain-related or neurological problems; some people with the disorder have developed with normal intelligence.
There is no treatment to change the head size but there are programs available to help these individuals reach their maximum potential and genetic counseling may help explain the risk in future pregnancies.
CDC and other agencies are advising women in tending to become pregnant not to travel to areas where Zika virus has been found.
No vaccines are available currently for Zika virus. No commercial test kits are available as at the time of publication of lifestyle Choices magazine. Transmission through breast milk has not been documented although the RNA has been detected in breast milk. Zika virus is not contagious.
Prevention is the same as for all arthropod borne infections-
Awareness of risk. Are you in travelling to an area with Zika virus case reports
Bites prevention by keeping environment clean and devoid of stagnant fluid and wastes for breeding of mosquitoes and most importantly wearing long sleeved and skin covering clothing; use of insect repellants such as DEET