Polio virus
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Morphology
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Polio virus is the type species of the Enterovirus genus in the family Picornaviridae.
Enteroviruses are transient inhabitants of the gastrointestinal tract, and are stable
at an acidic pH. Picornaviruses are small with an RNA genome. There are three poliovirus
serotypes (P1, P2, and P3). Immunity to one serotype does not produce immunity to
the other serotypes.
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Disease
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Poliomyelitis, polioencephalitis
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Zoonosis
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Poliovirus only infects humans.
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Host Range
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Humans. No endogenous reservoir exist in the United States.
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Modes of Transmission
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Person to person transmission can occur through fecal oral route and via infected
feces and body fluids. Contact precautions should be used. Note that alcohol-based
hand sanitizers do not kill poliovirus.
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Signs and Symptoms
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Polio invades the nervous system, and can cause total paralysis in a matter of hours.
The virus enters the body through the mouth and multiplies in the intestine. Initial
symptoms of polio include fever, fatigue, headache, vomiting, stiffness in the neck,
and pain in the limbs. In a small proportion of cases, the disease causes paralysis,
which is often permanent.
Polioencephalitis is rare and generally occurs in infants. Between 25-50% of survivors may develop postpolio syndrome experienced over their remaining life as muscle weakness and extreme fatigue. |
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Infectious Dose
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Unknown
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Incubation Period
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9-12 days
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Prophylaxis
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Vaccination.
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Vaccines
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If potential exposure, check antibody to Polio. A positive antibody indicates protection.
IPV – Inactivated polio vaccine recommended if no antibody. OPV – Oral Polio vaccine- No longer distributed in the United States |
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Treatment
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There is no specific treatment for polio. Persons infected with polio need supportive
therapy, such as bed rest and fluids. Severe paralytic disease impacting diaphragm
may require mechanical ventilation.
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Surveillance
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Polioviruses usually can be isolated from throat secretions in the first week of illness
and from feces, often for several weeks. In the absence of a viral isolate, the diagnosis
of poliovirus infection can be established serologically by testing paired acute and
convalescent sera for neutralizing antibodies to each of the three poliovirus serotypes.
Serologic tests cannot distinguish between wild-type virus and vaccine virus infection.
These viruses can be detected by PCR.
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MSU Requirements
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Report any potential exposures.
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Laboratory Acquired Infections (LAIs)
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Many potential LAIs in vaccine production facilities.
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Sources
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Cultures, frozen stocks, other samples described in IBC protocol.
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Canadian MSDS:
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n/a
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BMBL
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CDC
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NIH Guidelines
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Risk Group 2
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Agents that are associated with human disease which is rarely serious and for which
preventive or
therapeutic interventions are often available. |
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BSL2
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For all procedures involving suspected or known infectious specimen or cultures.
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ABSL2
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For all procedures utilizing infected animals.
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Small
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Notify others working in the lab. Remove PPE and don new PPE. Cover area of the spill
with absorbent material and add fresh 1:10 bleach:water. Allow 20 minutes (or as directed)
of contact time. After 20 minutes, cleanup and dispose of materials.
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Large
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• Immediately notify all personnel in the lab and clear all personnel from the area.
Remove any contaminated PPE/clothing and leave the lab.
• Secure the area by locking doors, posting signage and guarding the area to keep people out of the space. For assistance, contact MSU's Biosafety Officer (406-994-6733) or Safety and Risk Management (406-994-2711). |
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Mucous membrane
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Flush eyes, mouth, or nose for 5 minutes at eyewash station.
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Other Exposures
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Wash area with soap and water for 5 minutes.
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Reporting
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Immediately report incident to supervisor, complete a First Report of Injury form, and submit to Safety and Risk Management.
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Medical Follow-up
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During business hours: After business hours: |
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Disinfection
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0.5% bleach solution is recommended disinfectant.
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Inactivation
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Polio virus is resistant to inactivation by common laboratory disinfectants such as
alcohol. The virus is rapidly destroyed by exposure to temperatures of 50°C or more,
autoclaving or incineration. It is readily inactivated by dilute solutions of formaldehyde,
bleach.
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Survival Outside Host
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Polio virus is very stable at an acidic pH and can remain infectious for long periods
of time in food and water.
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Minimum PPE Requirements
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Lab coat, disposable gloves, safety glasses, closed toed shoes, long pants
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Additional Precautions
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Additional PPE may be required depending on lab specific SOPs and IBC Protocol.
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