Zika virus is primarily spread through bites from infected mosquitoes. Mosquitoes can become infected when they bite infected persons and can then spread Zika to other people they subsequently bite. There have been more than 100 locally transmitted cases of Zika in Florida since the end of July 2016,1 and all US states, with the exception of Alaska, have had travel-associated cases of Zika. Outdoor workers may be at the greatest risk of occupational exposure to Zika. As a result, OSHA has issued guidance to employers in order to help protect workers.2

OSHA recommends that employers train workers about their risks of exposure to Zika through mosquito bites and direct contact with infectious blood and other bodily fluids and how to protect themselves. Employers should also provide information about Zika virus infection, including modes of transmission and possible links to birth defects, to workers who are pregnant or may become pregnant or whose sexual partners are or may become pregnant.

Infection and Transmission

During the first week of infection, Zika can be detected in the blood and is capable of being spread from an infected person to a mosquito that feeds on that person. Infected mosquitoes can then spread the virus to other people through bites. In some instances, having direct contact with infectious blood or other bodily fluids (such as through sexual transmission) of an infected person may result in transmission of the virus. Zika can also be spread from a pregnant woman to her fetus and has been linked to a serious birth defect of the brain called microcephaly in babies of mothers who had Zika while pregnant.

OSHA has communicated the below recommendations through their article Interim Guidance for Protecting Workers from Occupational Exposure to Zika Virus.

OSHA Recommended Employer and Employee Actions

  • Employers should ensure that supervisors and all potentially exposed workers are aware of the symptoms of Zika, which include fever, rash, muscle or joint pain, headache (especially with pain behind the eyes), and pink or red eyes.
  • Employers should provide insect repellents and encourage their use.
  • Employers should provide workers with, and encourage them to wear, clothing that covers their hands, arms, legs, and other exposed skin. In warm weather, workers should consider wearing lightweight, loose-fitting clothing and/or hats with mosquito netting to protect the face and neck.
  • Employers and employees should get rid of sources of standing water (e.g., tires, buckets, cans, bottles, barrels) whenever possible to reduce or eliminate mosquito breeding areas.
  • If requested by a worker, employers should consider reassigning anyone who indicates she is or may become pregnant, or who is male and has a sexual partner who is or may become pregnant, to indoor tasks to reduce their risk of mosquito bites.
  • Employers should train workers to seek medical evaluation if they develop symptoms of Zika.
  • Employers should consider options for granting sick leave during the infectious period, which is typically during the first week of illness. During this time, infected workers should protect themselves and others from mosquito bites.

OSHA Guidance on Use of Insect Repellents

  • Always follow label precautions when using insect repellent.
  • Use insect repellent containing an EPA-registered active ingredient. Research suggests that repellents containing DEET or picaridin typically provide longer-lasting protection than other products, and oil of lemon eucalyptus provides longer-lasting protection than other plant-based repellents. Permethrin is another long-lasting repellent that is intended for application to clothing and gear, but not directly to skin.
  • Choose a repellent that provides protection for the amount of time that the worker will be outdoors. In general, the more active ingredient (higher concentration) a repellent contains, the longer it will protect against mosquito bites. Studies suggest that concentrations of DEET above approximately 50 percent do not offer a marked increase in protection time against mosquitoes; DEET efficacy tends to plateau at a concentration of approximately 50 percent.
  • Do NOT spray aerosol or pump products in enclosed areas.
  • Do NOT spray insect repellent on skin that is under clothing.