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The global rates for poliomyelitis are low, but children and adolescents need to be vaccinated against the disease. The Western Hemisphere was certified as free of the wild-type of virus in 1994, but there is some risk of vaccine-associated poliomyelitis from oral polio vaccine. Many public health authorities recommend a series of vaccinations for children from two months to 6 years.

Many inner-city children appear to be adequately immunized against polio. Researchers measured antibodies to the oral polio vaccine (OPV) in blood samples from 224 inner-city children in Houston and 302 in Detroit. Approximately 80% of the children had antibodies against the three types of poliovirus by the time they were two years old and more than 90% had poliovirus antibodies by the time they were three or four years old. Half of the Detroit children and one-quarter of the Houston children had received three doses of polio vaccine by the time they were two years old. Ninety percent of these children had antibodies against the three types of poliovirus. Almost half of 113 unvaccinated children had antibodies against at least one type of poliovirus. These children acquired their immunity from contact with a vaccinated child. Given the high immunization rates in these children and the fact that OPV can cause paralysis, it seems reasonable to switch to using inactivated poliovaccine (IPV) for the first two doses., Objectives.--To assess susceptibility to poliomyelitis in selected inner-city preschool children in the United States and to estimate the contribution of secondary spread of live attenuated oral poliovirus vaccine virus to type-specific immunity. Design.--Cross-sectional seroprevalence study. Methods.--Serum neutralizing antibody levels against poliovirus types 1, 2, and 3 were analyzed according to vaccination status, age, and other sociodemographic variables. Setting.--Hospital and satellite clinics serving inner-city populations in Houston, Tex, and Detroit, Mich, 1990 to 1991. Participants.--A total of 526 children aged 12 to 47 months seeking medical care were enrolled in the seroprevalence study; 144 children aged 12 to 35 months without a history of previous oral poliovirus vaccination were enrolled in the secondary spread study. Results.--Seropositive rates were similar in children in both cities, ranging from about 80% for types 1 and 3 in 12- to 23-month-old children to more than 90% in those aged 36 to 47 months. The most important predictor of seropositivity was the number of doses of oral poliovirus vaccine received (P

The West Bank and Gaza are two developing areas located adjacent to Israel where many people live in crowded refugee camps with inadequate sanitation. These conditions favor the spread of certain diseases such as polio, a virus that can, if severe, paralyze its victims. The government of Israel, which has official control over the West Bank and Gaza, initiated a major program to immunize children against polio in the early 1970s. Even though the vaccination campaign reached over 90 percent of children by 1977, many new cases of paralytic polio were still diagnosed. Some children who developed the disease had been immunized with at least one and up to four of the necessary four doses of oral polio vaccine (OPV) given during the first year of life. Researchers determined that the OPV was indeed potent, but it was not absorbed adequately in children who had diarrhea due to other viruses. In response to the limited success of the OPV, strategies were changed in 1978; a combination of five doses of OPV and two doses of inactivated polio vaccine (IPV), given by injection, was administered. This approach was effective and polio has been controlled in West Bank and Gaza during the 10 years following its implementation. The OPV-IPV combination is recommended for use in developing areas. Although it is relatively expensive, it may be essential for reaching the goal of worldwide eradication of polio.

The United States has been free of wild poliovirus-associated paralytic disease since 1979 due to universal vaccination with oral poliovirus vaccine (OPV). However, eight to nine paralytic poliomyelitis cases caused […]

One of the goals of the World Health Organization (WHO) is to eliminate polio from the world by the year 2000; it is possible that the last case in the Western hemisphere has already been identified. Ciro de Quadros, an official of the Pan American Health Organization (PAHO), the WHO agency that runs the vaccination program, has high hopes for its success. In fact, it has been so effective in the Americas that PAHO's program is now to serve as a model for the worldwide eradication program. An estimated 185,000 cases of polio occurred throughout the world in 1990. Between 1985 and 1990, however, the number of reported cases of polio climbed in Central and South America, while the number of confirmed cases dropped (from 1,100 to 10 in the latter year). This reflects better health care awareness of the disease, better reporting systems, and better prevention. In 1978, only 36 percent of children younger than one year old were vaccinated against polio; by 1989, however, this number had grown to 86 percent. PAHO's efforts were aided by businesspeople, particularly those in Rotary clubs, who organized vaccination drives, and by volunteers who carried out the vaccinations. A fee was paid to anyone who reported a confirmed case of polio. Other efforts are described. Mop-up operations begin when a case of flaccid paralysis (a kind of paralysis that can be polio) is reported; workers immediately vaccinated every child under the age of five in the neighboring area. Details of the few cases in specific countries are presented. Before this part of the world can be considered polio-free, virus must be undetected for three years. This is expected to occur by early 1994, according to de Quadros. New surveillance methods will be able to detect remarkably small levels of polio virus in sewage (as little as one viral particle in a sample). The agencies that have contributed funds to help eradicate polio in the Americas are listed. The cost per child for vaccination is 10 cents. (Consumer Summary produced by Reliance Medical Information, Inc.)

Extensive vaccination campaigns have apparently eliminated wild poliovirus in the Western Pacific Region. In 1990, polio was still endemic in Cambodia, China, Laos, Malaysia, Mongolia, Papua New Guinea, Philippines, and Vietnam. In 1991, many of these countries began supplemental vaccination programs. Cambodia and Vietnam established four National Immunization Days along the Mekong River and its tributaries between 1996 and 1998, where many residents do not have access to vaccination. Because of these efforts, the number of reported polio cases in the Western Pacific Region dropped from approximately 6,000 in 1990 to zero in 1998.