Poliovirus

(This page is part of a series. For information on other illnesses that can affect NPS employees, volunteers, commercial use providers, and visitors, please see the NPS A–Z Health Topics index.)

Source: CDC

THE BASICS:
Humans: Polio is caused by a virus that is spread through person-to-person contact, through contact with the stool or droplets of an infected person. Most people infected with poliovirus will not have any visible symptoms; about 1 in 4 will develop flu-like symptoms; and an even smaller proportion of people can develop more serious symptoms that affect the brain and spinal cord, causing meningitis and/or paralysis.There are two types of vaccine that prevent poliovirus. The oral poliovirus vaccine (OPV) contains weakened types of polioviruses and is used in many countries and outbreak situations, as it stops transmission. One disadvantage of OPV is that in rare cases, the weakened vaccine virus may be able to circulate, mutate, and cause disease, including paralysis. The inactivated poliovirus vaccine (IPV), which is the type of vaccine used in the United States, does not contain live virus and thus cannot cause disease. The complete series has been found to be extremely effective (>99%) in preventing paralytic polio. As a result of vaccination, many countries, including the United States, have been able to eliminate the disease. Unfortunately, in July 2022, the CDC became aware of a case of polio in an unvaccinated individual in New York.

Animals: Animals are not known to be reservoirs for poliovirus. This is one reason why public health professionals think and hope that polio can one day be eradicated.

Environment: Poliovirus can survive at room temperature for a few weeks but is rapidly inactivated by heat, formaldehyde, chlorine, and ultraviolet light. Since a human case of poliovirus was identified in the U.S. in 2022, some wastewater samples have been found positive for poliovirus. To date, the virus has only been identified in areas of New York. Those areas are published here.

PREVENTION:

• Confirm that you have received the childhood vaccination series. The childhood series involves 4 shots.
• If you have not received the childhood vaccination series, follow the recommended “catch-up” schedule, which involves 3 shots and can be found here.
• Additionally, if you are at increased risk of exposure, talk to your doctor about potentially getting a booster dose on top of your childhood vaccines.
• For employees, consider risks of poliovirus exposure when conducting job hazard analyses and ensure appropriate training on sewage and waste handling. In working in areas known or suspected to have circulating polioviruses, please see guidance from the U.S. National Authority for Containment of Poliovirus (NAC).

RESPONSE:

• If you become ill following a potential exposure, contact your healthcare provider and let them know of your concern. Also, please report any confirmed illnesses to the NPS Office of Public Health ([e-mail]) as directed in the “Disease Reporting” guidance below.

Last updated 12/12/2022

Resources

• CDC polio webpage
• CDC “Pink Book” polio chapter
• European CDC poliomyelitis factsheet
• For employees: U.S. National Authority for Containment of Poliovirus. “How to Protect Yourself When Sampling Wastewater in Areas Known or Suspected to Have Circulating Polioviruses (PV)."

Disease Reporting

Visitors: Please email us to report any disease or health concern you believe may be related to your visit. You should also contact your healthcare provider who will report any confirmed and reportable disease on your behalf to the local or state health department.

Concessioners & Partners: Please email us to report illnesses as defined in NPS guidance and policy and in the Concessions contract.

Employees & Volunteers: NPS staff should report all employee and volunteer incidents as defined in NPS guidance and policy by contacting your NPS Public Health Consultant (restricted access), or you can email us. All work-related exposures and illnesses must also be reported in the Safety Management Information System (SMIS) (restricted access). All known disease exposures should be reported in SMIS as well.