Chikungunya Virus

Abstract

A mosquito-borne viral disease that is creating increased concern globally is Chikungunya virus (CHIKV). Occupational and environmental health nurses should educate workers about this emerging viral infection.

Work hazards in agriculture, construction, forestry, and other outdoor jobs can include extreme heat and high humidity, but sometimes overlooked are viruses acquired from mosquito bites, such as Chikungunya virus (CHIKV). Two species of mosquitoes typically found in tropical and subtropical climates are responsible for dengue fever and also CHIKV, which has no vaccination or cure. Humans are the main reservoirs of the virus; laboratory workers handling infected blood, and health care workers drawing blood from infected patients, have contracted CHIKV (Staples, Hills, & Powers, 2014).

After the first recognized outbreak in 1952, sporadic outbreaks of CHIKV occurred in Africa, Southeast Asia, and India. After 2000, the number of outbreaks increased; nearly 2 million cases were reported in India, Indonesia, Maldives, Myanmar, and Thailand since 2005. European officials reported their first disease transmission during a localized outbreak in northeastern Italy in 2007 followed by outbreaks in France and Croatia. The first case in the Americas was in St. Martin in 2013; as of April 2015, nearly 1.4 million cases and 191 deaths have been recorded in the Caribbean islands, Latin American countries, and the United States. Global travel contributes to worldwide outbreaks with cases now reported in some Pacific Islands (World Health Organization, 2015).

Infected individuals usually develop symptoms 3 days to 7 days after exposure (range = 1 day-12 days), which resolve within 7 days to 10 days. The virus is differentiated from dengue by acute onset of high fever above 39 ºC (102 ºF) with bilateral, symmetric, severe, and often debilitating joint pain (Centers for Disease Control and Prevention [CDC], 2015a). Headache, myalgia, arthritis, conjunctivitis, nausea and vomiting, or maculopapular rash also occur. Although seldom fatal, rare complications include uveitis, retinitis, myocarditis, hepatitis, nephritis, bullous skin lesions, hemorrhage, meningoencephalitis, myelitis, Guillain-Barre’ syndrome, and cranial nerve palsies. Associated laboratory findings are lymphopenia, thrombocytopenia, elevated creatinine, and elevated hepatic transaminases (CDC, 2015a).

CHIKV is present throughout the United States (CDC, 2015b) and is reported in the National Notifiable Diseases Surveillance System (NNDSS; CDC, 2015c). Although a field-ready dipstick assay is in development, confirmation of CHIKV is currently through specialized laboratory assays from select state health departments and the CDC.

Occupational and environmental health nurses should educate workers about this emerging viral infection and to report international travel. Workers with underlying health conditions or late in pregnancy are most at risk. Teach all workers to use insect repellent, wear long sleeves and pants, and stay where air conditioning or window and door screens are used when working in or traveling to areas with CHIKV. Removing mosquito breeding grounds (e.g., standing water) is most effective in reducing exposure risk to these aggressive day-time biters. Workers recently returned from CHIKV infected areas complaining of acute onset of fever or polyarthralgia require close monitoring.