A little-known virus of equatorial Africa and Asia, the Zika virus has “jumped the pond” and is wreaking havoc in South America, especially among pregnant women and their newborns. Like its predecessors, it’s a mosquito-borne virus. Citizens of the Americas have little immunity against it.
Most people experience mild flu-like symptoms, but an infected during a pregnancy can yield a newborn with brain damage. In late 2015, it was mainly a Brazilian problem. A congenital abnormality (once called a “birth defect”) called microcephaly started appearing among newborns.Microcephaly presents as an abnormally small head and is associated with mental handicaps; if severe, it may be incompatible with life.
Brazil is a large country with a youthful population; in an average year, it sees about 150 cases of microcephaly. Since the arrival of Zika virus in May 2015, there have been 3,500. Now, cases of the virus are being reported in the United States from Virginia to Arkansas to Hawaii (mostly in returning travelers from South America). In total, 25 countries so far are reporting evidence of the virus.
EPIDEMICS VS. PANDEMICS
Infectious disease can be endemic, epidemic, or pandemic:
–An Epidemic infectious disease is a community-wide outbreak of an illness that is not always present in an area. Influenza, EnterovirusD68, and Ebola are examples.
–An Endemic infectious disease is one that is normally found and expected in a certain area. Malaria is endemic in many tropical countries.
–A Pandemic occurs when an infectious disease crosses various borders and runs rampant throughout a large region, or even the whole world. The Spanish Flu of 1918 is the classic example. Zika has had outbreaks in Africa, Asia, and now, South America. Cases have been reported in Denmark and Sweden as well.
WHAT IS ZIKA VIRUS?
Zika virus is a member of the Flavivirus family, which contains a number of well-known diseases such as yellow fever, chikungunya, and West Nile virus. Like the others, Zika virus is carried by Aedes mosquitoes, which are the main agent of transmission (human to human transmission can also occur); unlike the others, the virus affects the unborn.
Symptoms of the virus include headache, rash, fever, and conjunctivitis(pink eye). The grand majority of infected people have no signs of the infection whatsoever. This is ominous for a pregnancy, as the mother doesn’t even know she was at risk.
TREATMENT AND PREVENTION OF ZIKA VIRUS
There is no vaccine or treatment available that is effective against Zika virus. Prevention, however, is simple: Don’t travel to the countries where widespread outbreaks are occurring. If you have to go, use sunscreen, long pants and sleeves, plus mosquito repellant or netting. Standing water near your location in affected areas should be drained.
Mosquito control efforts are underway in Brazil and other countries at risk. Besides the usual sprays with pesticides, you might be surprised to know that GMOs (genetically modified organisms) are playing a part.
A male “Franken-mosquito” called OX513A has a gene that kills his offspring. Female mosquitoes only mate once during their lives, so this might have a significant effect. Brazil claims more than a 90% decrease in the population after release. OX513A was also used in the Florida Keys in 2012 (over protests) to combat an outbreak of another Flavivirus, Dengue Fever.
Joe Alton, MD