OrimuneŽ Vaccine (Live Poliovirus Oral Vaccine-OPV)
Available as a mixture of three types of attenuated polioviruses in a 0.5 ml single-dose Dispette
Description: Oral poliovirus vaccine (OPV) contains live attenuated poliovirus (Sabin strain types 1, 2 and 3) and is intended for polio prophylaxis in infants 6-12 weeks of age, all unimmunized children up to 18 years of age, and high-risk adults. Adults, however, should receive the inactivated poliovirus vaccine (IPV). The attenuated virus particles inOPV are harvested from monkey kidney cell cultures and undergo an extensive purification process.OPV is administered multiple times to ensure immunity to all three types of poliovirus. Clinical studies reveal thatOPV is highly effective in preventing natural poliovirus-induced neurologic sequelae.OPV received FDA approval in1963.
Mechanism of Action: The oral poliovirus vaccine stimulates the immune system to produce anti-poliovirus antibodies against Sabin poliovirus types 1, 2, and 3.
Several studies suggest that intestinal resistance can persist for 6 years after vaccination.
ˇPoliovirus vaccine live oral,OPV is administered orally.OPV must not be administered parenterally.
ˇMay be administered directly into the mouth using the single-dose pipette supplied by the manufacturer. Alternatively, mix with distilled or chlorine-free water, syrup, or milk, or adsorbed on bread, cake, or sugar cube.
ˇIf a dose is not swallowed, spat out, or a substantial portion is regurgitated or vomited shortly after administration (i.e., within 5-10 minutes), a second dose should be given. If the second dose is not retained, do not count either dose, readminister on the next visit.
For poliovirus prophylaxis:
Adults: 0.5 mL PO initially, then repeated 8 weeks later. The third dose should be given 8-12 months after the second dose. When less than 4 weeks is available before immunization is required, a single 0.5 ml PO dose should be given.
Infants: The first 0.5 ml PO dose should be administered at 6-12 weeks of age. The second 0.5 ml PO dose should be administered preferably 8 weeks after the first dose. The third 0.5 ml PO dose should be administered at 6 months of age, however, if this time cannot be met, the third dose may be administered as late as 18 months of age.
Patients with renal impairment:
Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.
The poliovirus vaccine should be used with caution in patients with a history of neomycin hypersensitivity or streptomycin hypersensitivity because these agents may be used in the preparation ofOPV. A history of delayed-type allergicreactions is not an absolute contraindication toOPV administration.
OPV may not be as immunogenic in elderly patients or in patients suffering from immunosuppression (congenital, acquired, or iatrogenic). Furthermore, virus particle production can be potentiated in immunosuppressed patients, soOPV use is not recommended in these individuals. Patients with HIV infection may receive IPV or enhanced-potency IPV; however,OPV should be avoided.
Patients with evidence of viral infection (diarrhea, vomiting) should not be givenOPV because other enteroviruses within the intestinal tract can inhibit immunity by preventingOPV replication. Similarly,OPV inoculation should be postponed in patients with fever or a severe respiratory infection, although minor illness does not precludeOPV administration.
Intramuscular injections, especially antibiotics, should be avoided for at least 30 days in patients who have received the poliovirus vaccine live oral (OPV) or for 60 days in patients who acquired the disease by contact with vaccine recipients. Intramuscular injections were associated with an increased risk of developing paralytic poliomyelitis in patients receiving IM injections 30 days prior to the onset of paralysis.
Poliomyelitis has occurred afterOPV administration both in vaccinees and in their close contacts. Poliovirus may be shed in the feces (and possibly from the pharynx) of vaccinees for 6-8 weeks afterOPV administration. Contact individuals should be warned of the small risk of developing poliomyelitis and informed to wash hands carefully when exposed to feces or saliva of recently inoculated vaccinees.
Concomitant administration of immunosuppressives (corticosteroids, alkylating agents, antimetabolites, radiation therapy) can decrease the immunological response toOPV and potentiate viral replication. Immunization should be deferred until the completion of immunosuppressive therapy, if possible.
Whenever possible, however,OPV and other live virus vaccines should be administered at least 1 month apart.
vaccines); and inactivated vaccines. However, concurrent administration ofOPV with cholera vaccine, typhoid vaccine, or plague vaccine may be associated with significant adversereactions and should be avoided.
Administration ofOPV is associated with a low incidence of paralytic poliomyelitis in vaccinees. Also, individuals in close contact with recently inoculated vaccinees may be at a small risk of developing paralytic poliomyelitis because poliovirus can be shed in the feces (and possibly from the pharynx) for 6-8 weeks afterOPV administration. Immunocompromised patients are also susceptible to this adverse reaction. The incidence of poliomyelitis is approximately 1 case per 2.6-5 million doses ofOPV administered. Most cases of poliomyelitis
In rare cases, Guillain-Barre syndrome has occurred afterOPV administration, although a causal relationship has not been established.
Anaphylactic shock has occurred rarely afterOPV administration and is manifest as urticaria, pruritus, erythematous skin, conjunctivitis, and sudden or severe fatigue. Cell-mediated, delayed-type allergicreactions (pruritus and rash) also have occurred but are less severe.
Fever can occur in as many as 5% of recipients receiving the injectable form of poliovirus vaccine. Fevers greater than 101.3 degrees F have been reported.