- Responding to Zika’s outbreak and spread involves stepped-up public-health efforts, including vector control of mosquitoes, work to expand public awareness, staff training, and development of treatment protocols.
- In 2016, Direct Relief established a Zika Fund and worked closely with health officials and facilities in 14 affected countries to fulfill requests for supplies.
- Zika funds have been used to boost support to partner organizations providing care in Zika-affected areas in the U.S., as well as Argentina, Colombia, the Dominican Republic, Guatemala, Guyana, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Peru, Paraguay, and El Salvador.
No Zika vaccine yet exists—responding to Zika’s outbreak and spread involves stepped-up public-health efforts, including vector control of mosquitoes, work to expand public awareness, staff training, and development of treatment protocols.
Tracking Zika by Mapping the Spread
HealthMap tracks the spread of infectious disease around the world by geocoding the locations of news stories about diseases, often allowing for more rapid outbreak detection than traditional laboratory-based methods.
Zika virus is an arbovirus, an insect vector-borne disease most commonly transmitted through Aedes (aegypti and albopictus) mosquitoes. Less commonly, Zika can be transmitted from mother to child during pregnancy. In some cases, Zika virus transmission also has been reported through exposure to infected blood or through sexual contact.
Zika is endemic to parts of Africa and Asia. Since early 2015, a large number of locally acquired cases (estimated to be as many as 1.5 million cases by the World Health Organization) have been discovered in Brazil, where the disease was previously unknown. The high number of cases and the novel locations of the outbreak made Zika a rapidly growing epidemic threat. Zika developed into a region-wide pandemic as human and mosquito travelers transmitted the disease to more than a dozen more countries throughout the Americas, leading the WHO to label it an international health emergency.
In November 2016, the WHO declared an end to Zika as a global health emergency. Zika is now considered endemic to countries where vectors are present and will be viewed as an ongoing threat, similar to other mosquito-borne diseases. As of August 2017, the Pan American Health Organization confirmed 48 countries and territories in the Americas to have vector-borne transmission of Zika virus, with 5 countries reporting sexually transmitted cases. In the U.S., as of December 20, 2017, the Centers for Disease Control provisionally reported 996 laboratory-confirmed cases of Zika virus in 2017 across the 50 U.S. states and 3 U.S. territories.
Zika Virus Symptoms
Symptoms of Zika virus in most people are similar to those of other arboviruses such as Chikungunya, including fever, headache, and fatigue. Zika, however, is distinctively marked by detection of the disease in amniotic fluid and increased cases of microcephaly (small head size) in newborns. The vast majority of cases of microcephaly in Brazil have been reported in the country’s northeastern region. Given the virus’ novel introduction to the Americas, some epidemiologists have expressed concern that resistance may be low, leading to heightened transmission rates and severity of symptoms.
In rare cases, Zika symptoms have been associated with Guillain-Barré syndrome, in which the body’s immune system attacks nerve cells in the peripheral nervous system. This can lead to weakness, numbness, tingling, and paralysis. A study published by The New England Journal of Medicine looked at the incidence of both Zika and Guillain-Barré across 7 countries: Brazil, Colombia, the Dominican Republic, Honduras, El Salvador, Suriname, and Venezuela. The study looked at the 1,474 cases of Guillain-Barré syndrome that were reported in those countries from April 2015 to March 2016. Comparing the timeline of reporting of Zika and Guillain-Barré during this period showed a close coincidence of the two diseases. For more information, please see “Zika Virus and the Guillain–Barré Syndrome—Case Series from Seven Countries.”
Environmental Factors in Zika Transmission
Zika virus was first identified in rhesus monkeys from Uganda’s Zika Forest in 1947 during the course of routine surveillance for yellow fever. Thereafter it was diagnosed in humans starting in 1952. During the 20th century, Zika became endemic in Africa and parts of Asia, only making the jump to the Americas beginning in 2015.
Significant circumstantial evidence links the spread of Aedes mosquitoes in the 2015–16 outbreak with a confluence of environmental factors in part attributable to climate change and the influence of the El Niño phenomenon. This confluence of environmental factors manifested in the form of increased heat and precipitation, particularly at lower elevations, which opened up new breeding areas for Aedes mosquitoes. With Zika virus now endemic to regions within the range of Aedes mosquitoes, additional cases are likely to emerge on a seasonal basis.
Direct Relief’s Zika Response
Direct Relief is supporting its global partner network in affected areas with resources such as pain medication, insect repellent, and contraceptives. The organization is in close communication with public health officials and facilities in countries throughout the Caribbean, Latin America, and North America, including leading emergency-response staff at national and state associations, health centers, and clinics across the U.S. Supplies have been provided to countries including Argentina, the Dominican Republic, the Federated States of Micronesia, Guatemala, Haiti, Honduras, Jamaica, Paraguay, Peru, El Salvador, the U.S., and Venezuela.
In March 2016, Direct Relief established a Zika Fund with an initial commitment of $100,000 in internal funds, toward which private contributions may be designated. All contributions to the fund are being used to support healthcare facilities in Zika-affected areas, with particular focus on the following measures.
- Maternal and child health: Provide pre- and postnatal resources needed for safe deliveries to support care for newborns.
- Prevention and treatment supplies: Distribute requested supplies, such as insect repellent, IV solutions, medications for fever reduction and pain relief, and contraceptives.
- Support for health facilities: Provide general in-kind and financial support to healthcare providers serving communities, especially in low-income areas, alleviating the strain placed on local health facilities by the surge in patients.
- Data analysis: Direct Relief has developed an online map to consolidate and share the most current reports from Direct Relief’s partners in affected areas, as well as information published by the World Health Organization and other governmental and nongovernmental public health agencies.
When a 7.8 magnitude earthquake struck Ecuador in April 2016, Direct Relief made available Zika prevention items such as insect repellent and contraceptives, addressing the increased exposure of displaced populations to the Zika virus.
Neither Direct Relief nor the partners requesting help had anticipated or budgeted for Zika response, so Direct Relief’s commitment of internal funds helped ensure funding for important efforts to get in front of a problem and public health concern that has continued to expand.
Zika funds have been used to boost support to partner organizations providing care in Zika-affected areas in the U.S., as well as Argentina, Colombia, the Dominican Republic, Guatemala, Guyana, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Peru, Paraguay, and El Salvador.
- Simon Cauchemez, et al., “Association between Zika virus and microcephaly in French Polynesia, 2013–15: a retrospective study,” The Lancet, 15 March 2016, accessed at Association between Zika virus and microcephaly in French Polynesia
- Van-Mai Cao-Lormeau, et al., “Guillain-Barré Syndrome outbreak associated with Zika virus infection in French Polynesia: a case-control study”, The Lancet, 29 February 2016, accessed at Guillain-Barré Syndrome outbreak associated with Zika virus infection in French Polynesia
- Donald G. McNeil Jr. and Catherine Saint Louis, “Two Studies Strengthen Links Between Zika Virus and Serious Birth Defects,” The New York Times, 4 March 2016, accessed at Two Studies Strengthen Links Between the Zika Virus and Serious Birth Defects
- Isaac I. Bogach, et al., “Anticipating the international spread of Zika virus from Brazil,” The Lancet, 23 January 2016, accessed at Anticipating the international spread of Zika virus from Brazil
- “Zika Virus: Transmission,” Centers for Disease Control and Prevention, accessed at Prevention and Transmission
- Brian Kahn, “What You Need to Know About Zika and Climate Change,” Climate Central, 28 January 2016, accessed at What You Need to Know About Zika And Climate Change
- H.M. Khormi and L. Kumar, “Climate change and the potential global distribution of Aedes aegypti: spatial modelling using GIS and CLIMEX,” Geospatial Health, 8 May 2014, accessed at Climate change and the potential global distribution of Aedes aegypti
- “WHO Director-General summarizes the outcome of the Emergency Committee regarding clusters of microcephaly and Guillain-Barré syndrome,” World Health Organization Media Centre, 1 February 2016, accessed at WHO Director-General summarizes the outcome of the Emergency Committee regarding clusters of microcephaly and Guillain-Barré syndrome
- “Zika Virus Fact Sheet,” World Health Organization, 6 September 2016, accessed at Zika virus
- Moritz U.G. Kraemer, et al., “The global distribution of the arbovirus vectors Aedes aegypti and Ae. albopictus,” eLife, 30 June 2015, accessed at The global distribution of the arbovirus vectors Aedes aegypti and Ae. albopictus