Revised IPV-OPV recommendations approved

ARTICLE REPRINT • From the December 1998 AAP News, the official news magazine of the American Academy of Pediatrics

Since 1997, when the American Academy of Pediatrics (AAP) issued revised guidelines for the prevention of poliomyelitis, substantial progress in global eradication of poliomyelitis has occurred. In the United States, the use of inactivated poliovirus vaccine (IPV) has increased considerably with a corresponding decrease in the use of oral poliovirus vaccine (OPV). Surveys indicate that the majority of physicians now routinely immunize children with the sequential IPV-OPV or IPV-only regimens. Neverthe- less, vaccine-associated paralytic poliomyelitis (VAPP) continues to occur, albeit infrequently, in children who have received the OPV-only regimen and their contacts. In order to further reduce the risk of VAPP, the Academy now recommends that children in the U.S. receive IPV for the first 2 doses of the polio vaccine series in most circumstances. Either IPV or OPV can be administered for the third and fourth doses. Assuming continuing progress toward global eradication, a recommendation of IPV-only immunization for children in the United States is anticipated by 2001.

Specific recommendations in the statement are as follows:

1. IPV is routinely recommended in most circumstances for all children at 2 and 4 months of age for the first 2 doses of the poliovirus vaccine schedule. Immunization with OPV is acceptable when parents refuse either IPV or the number of injections needed to administer the other recommended vaccines for infants.

2. In accordance with either the sequential or IPV-only regimen, OPV or IPV should be given at 6 to 18 months and 4 to 6 years of age for a total of 4 doses of polio vaccine administered before school entry. If OPV is to be given for the third and fourth doses, some experts recommend delaying the third dose until 12 months of age in order to minimize the chance of inadvertently administering OPV to a child with an underlying, unrecognized immune deficiency.

3. Only IPV is recommended for the following:

a) immunocompromised persons and their household contacts because OPV is contraindicated in these individuals.
b) infants and children in households with persons older than 17 years who are known to be inadequately vaccinated against poliomyelitis because of the increased risk of VAPP in susceptible adults.

4. For infants and children in whom the routine im- munization schedule is not initiated until after 6 months of age and in whom an accelerated schedule is necessary to fulfill immunization recommen- dations, an OPV-only regimen is acceptable to minimize the number of injections at each visit.

5. For children who may be travelling to areas where wild-type poliovirus is still endemic, selection of IPV or OPV depends upon the interval until departure and the number of doses of polio vaccine previously received. If a child who has not been previously immunized will be travelling in 2 months or more, 2 doses of IPV at a minimal interval of 1 month are recommended. OPV or IPV should be given subsequently to complete the schedule. If the child will be travelling in less than 2 months and has not received prior doses, a single dose of either OPV or IPV should be given and the immunization schedule should be continued after arrival in the foreign country. For children who already have received 2 doses of IPV, administration of 2 doses of OPV at an interval of at least 1 month will provide optimal intestinal immunity. In all cases, children who have not completed the immunization schedule by the time of departure should do so as soon as possible, including receiving vaccinations in a foreign country, if necessary.

6. If an outbreak of wild-type poliovirus infection occurs in the United States, OPV is the vaccine of choice in order to most effectively control the spread of infection. The AAP supports the need for sufficient federal resources to ensure an adequate supply of OPV for outbreak control in such a public health emergency.

7. As with administration of all vaccines, parents and other caregivers should be informed of the benefits and risks of the different poliovirus vaccines and regimens, including the risk of VAPP from OPV. The Vaccine Information Statement on polio vaccines should be provided as required by law. Current information statements can be obtained from the AAP Division of Publications, state health department immunization programs, or the CDC Web site (http://www.cdc.gov/nip/vistable.htm).

8. Precautions and contraindications in the administration of IPV and OPV remain unchanged from prior recommendations given in the current (1997) edition of the Red Book: Report of the Committee on Infectious Diseases.

9. The AAP continues to support the WHO recommendation for the use of OPV to achieve global eradication of poliomyelitis, especially in countries with continued or recent circulation of wild-type poliovirus.

The Recommended Childhood Immunization Schedule, United States, January - December 1999, approved by the Advisory Committee on Immunization Practices (ACIP), the American Academy of Pediatrics, and the American Academy of Family Physicians, will be published in the January 1999 issue of AAP News and Pediatrics.