Zika: From nuisance to ‘genuine threat to public health’
Surgeon looks at new concerns surrounding an old virus
The Zika virus? Up until recently, you probably had never heard of it.
Discovered in Uganda in 1947 by scientists who were working to understand mosquito borne illnesses, the Zika virus has never been high on the radar of medical professionals. Transmitted via the bite of an infected Aedes mosquito, Zika was thought to be a “weak” cousin of the more dangerous viruses that caused diseases such as Dengue Fever and Chikungunya. Many people who contracted the virus showed no obvious symptoms. The people who got sick could expect mild to moderate discomfort due to symptoms which include fever, fatigue and a rash. Symptoms often lessened or stopped in a few days and no significant after effects were noted.
In essence an encounter with Zika was considered to be no more distressing than the common cold … until now.
Understanding that the Zika virus was thought to be isolated in the Eastern Hemispheres (Africa and Asia), those in the West had little reason to be aware of this puny, little pathogen. However, all of that changed over the course of 2015 when the country of Brazil noted a sharp spike in the number of newborns being delivered with a unique birth defect: microcephaly.
Microcephaly, is a medical term for an abnormally small head. The causes of microcephaly can vary, but in this instance the small skull was directly related to abnormal fetal brain development. In a normal year, we would expect to see a few hundred children born with microcephaly, but in 2015 over 3,900 children were born with microcephaly in Brazil. This was an astounding tenfold increase in occurrence. Trying to explain the sudden rise in microcephaly, specialists in Belem, Brazil examined the amniotic fluid of pregnant women carrying microcephalic babies. Results demonstrated the presence of the Zika virus in the fluid indicating that is could be a “causative agent.” Subsequently the Centers for Disease Control and Prevention (CDC) solidified the link when it isolated the virus in the brain tissue of microcephalic neonates who had died shortly after birth. All findings seem to indicate that the Zika virus has developed from a nuisance to a genuine threat to public health around the world.
Is it time to be concerned? Sure, but probably the real take home message is to be aware. Zika is in the Western hemisphere and if past history is any indication of future reality, Zika will not stay isolated to Brazil and South America. The virus can be expected to move north through Puerto Rico and South America, winding its way into the southern states. Already cases have been reported in South America, the Caribbean and Polynesia, as well as more than a dozen states in the U.S., including Hawaii, Florida and one in Texas, but these cases do not appear to be native born; rather they arose in mothers who travelled to countries where Zika is in evidence. Any area that contains the appropriate carrier mosquito is at risk.
Is there a vaccine, or antibiotic to manage the disease? Zika is new as a frontline viral threat and as such no vaccines are yet available. Antiviral medication do exist but their efficacy against the Zika virus is not known so the key to staying Zika-free is an avoidance protocol. Remembering that the, the major new alarms surrounding Zika are related to pregnancy, and specifically the neural development in the first trimester, it is newly pregnant women that are at greatest risk. These new mothers-to-be should avoid any areas know to harbor the Zika virus. Wearing long pants and long sleeve shirts creates a protective clothing barrier and in areas where open ventilation is present, mosquito netting has proven very effective in warding off flying pests. Pregnancy safe mosquito repellents are recommended and areas with standing stagnant water should be drained so that mosquito populations can be controlled. Given the newness of the problem, with Zika, an ounce of prevention is the only known “cure.”
World Health Organization
Pan American Health Organization