The majority of healthcare providers in the United States (US) first became familiar with Zika virus in early 2016 when it gained national attention following a large Zika virus outbreak in Brazil in 2015. With this outbreak, a concurrent increase in rates of microcephaly and ocular abnormalities in newborns was observed, suggesting an association between the two (Martines, 2016). Subsequent, retrospective analysis of a Zika outbreak in French Polynesia in 2013-2014 further supported the association between Zika virus infection and neurologic birth defects in newborns (Martines, 2016). The Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) first issued public health alerts in January 2016 and February 2016 to increase public awareness, mobilize resources, and expand knowledge of Zika virus. A priority of these efforts was preventing infection in pregnant women and women of reproductive age to avoid birth defects resulting from transmission of Zika virus to the fetus.

Since the initial public health alert, the CDC has provided extensive guidance and resources for healthcare providers based on current knowledge of Zika virus. Although the virus can be asymptomatic in adults, we know that it can cause significant morbidity and mortality to a fetus when contracted in utero, most significantly microcephaly and fetal demise.

Since the initial advisories of 2016, scientists and healthcare professionals have gained a better understanding of both transmission and the pathophysiologic effects of the virus. The CDC has an extensive system of surveillance, and a registry to monitor cases in the US as well as a registry of all pregnant women with Zika virus infection (the US Pregnancy Zika Virus Registry [USPZR]). All serologic testing for Zika virus is monitored through the CDC allowing for accurate and detailed surveillance.

From the perspective of the healthcare provider, some of the more significant benefits of the CDC efforts have been the provision of straightforward guidelines for prevention and screening, and anticipatory guidance specific to pregnant women and women of reproductive age. Nurses play a critical role in educating patients and families and can be instrumental in reducing fears by providing patients with the accurate and up-to-date information necessary to remain healthy and reduce the risk of Zika virus infection and spread.

What We Know about Zika virus in 2017 (CDC, 2017):

• Zika virus is spread primarily through the bite of the Aedes species of mosquito which are known to bite during both day and night.
  • The most effective way to prevent Zika virus is to take measures to prevent being bitten by mosquitoes.
• Zika virus can be passed from a pregnant woman to her fetus and is linked to neurologic birth defects, specifically microcephaly.
  • Pregnant women should not travel to geographic regions with risk of Zika.
• Zika virus can be passed sexually from a person who has Zika virus to his or her sex partners.
  • Pregnant women living with partners who have Zika virus or have traveled to regions with Zika virus should not have sex with their partner, or should use barrier protection/condoms during pregnancy.
  • Women of reproductive age (those reproductive planning and those at risk for unplanned pregnancy) should receive counseling similar to that of pregnant women in respect to risk reduction of Zika infection.
• During the first week of infection, a person can spread Zika virus by being bitten by a mosquito that subsequently bites another person exposing them to blood containing Zika virus.
• Most cases of Zika virus are asymptomatic; if symptoms are present, they may include fever, malaise, maculopapular rash, conjunctivitis, headache, and arthralgia.
• There is no specific treatment or vaccine for Zika virus.
• There has been mosquito-borne transmission of Zika virus in the continental US; the first confirmed case was August 1, 2016 in Miami, Florida.

 

Summary of CDC recommendations for the care of the pregnant woman (CDC, 2017): 

Major Recommendations	Pregnant women should not travel to areas with risk of Zika infection. Pregnant women should use condoms/barrier protection with any sexual partner that lives in or has traveled to areas with risk of Zika.
Prenatal Care	Screen for potential Zika virus exposure at all prenatal visits. Examples of screening tools and testing algorithms can be found on the CDC website. If exposure screening is positive, screen for symptoms (fever, rash, arthralgia or conjunctivitis) and/or fetal abnormalities on ultrasound. Symptomatic women with possible Zika exposure should undergo serologic and/or urine testing for Zika virus. Zika virus testing of asymptomatic women with potential Zika exposure varies based on region of travel.    Zika virus testing includes: Zika virus nucleic acid testing (NAT) (i.e. RNA) in urine and serum Serum Zika virus and dengue virus immunoglobulin M (IgM) If IgM is positive, equivocal, presumptive or possible, must confirm with serum plaque reduction neutralization test (PRNT) which tests viral specific neutralizing antibodies to Zika.
Management of pregnant women with Zika virus infection	Consider serial ultrasound every 3-4 weeks to evaluate for fetal abnormalities Amniocentesis on a case by case basis
Management of pregnant women with potential exposure and no serologic evidence of Zika infection	Ultrasound to evaluate for fetal abnormalities. If fetal abnormalities present, consider repeating Zika virus NAT and IgM testing. If no fetal abnormalities, continue routine prenatal care and risk management for Zika virus exposure.
Postnatal recommendations in women with positive or presumptive Zika virus infection during pregnancy	Live birth: infant serum and urine testing for Zika virus NAT and Zika/Dengue IgM as well as Zika virus NAT and immune-histochemical (IHC) staining of umbilical cord and placenta; test CSF if available. Fetal losses: Zika virus NAT and IHC staining of fetal tissues. Breastfeeding is recommended. Zika virus has been found in breastmilk but there have not been reports of infection associated with breastfeeding; the benefits are thought to outweigh the theoretical risks of transmission via breast milk.

 
When a pregnant woman passes the Zika virus to her fetus during pregnancy, it can lead to congenital Zika syndrome (CDC, 2017b). While the full extent of potential health effects from Zika virus is unknown, we know that congenital transmission can lead to brain abnormalities including severe microcephaly, eye abnormalities, congenital contractures (clubfoot or arthrogryposis), hypertonia restricting movement soon after birth and hearing loss (CDC, 2017a, CDC, 2017b). There is guidance from the CDC for healthcare providers on neuroimaging of infants  with congenital Zika syndrome as well as specific guidance for the management of infants with Zika virus infection for the first 12 months, regardless of the presence of birth defects. The CDC is also responsible for the development of Zika Care Connect, which provides a network of referral sources and specialty healthcare services helping to facilitate access to resources for families affected by Zika virus.

Zika virus is a classic example of an emerging infectious disease in the US. The response from the CDC and WHO has been critical in making the public aware of this threat and successfully mobilizing resources to provide healthcare providers with the most current, scientifically-based evidence available. Nurses are often the first clinical contact a patient will have with the healthcare system.  We are in a position to educate and decrease fears associated with Zika virus, which was an unknown threat to most in the US less than 2 years ago. A major focus of education should be prevention, including educating patients on taking measures to prevent being bitten by mosquitos and efforts to reduce risk by informing patients of travel precautions to areas with risk of Zika infection for pregnant women, women of reproductive age and women and their partners trying to conceive. With this, we can contribute in public health efforts to prevent the spread of an emerging virus which poses serious health risks and the potential for catastrophic effects on newborn morbidity and mortality.

References:
Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Division of Vector-Borne Diseases, (2017a). Zika Virus. Retrieved from: https://www.cdc.gov/zika/index.html June 2017.
Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Division of Vector-Borne Diseases, (2017b). Zika, CDC Interim Response Plan, May 2017. Retrieved from: https://www.cdc.gov/zika/public-health-partners/cdc-zika-interim-response-plan.html
Martines, Roosecelis Brasil et al. (2016). Pathology of congenital Zika syndrome in Brazil: a case series. The Lancet, 388(10047), 898-904.

 
Megan Doble, MSN, RN, CRNP, FNP-BC, AGACNP-BC