Human poxvirus disease after smallpox eradication.

A 5-year-old boy living in a small camp in the rural Ivory Coast had a disease resembling smallpox. This occurred 4 years after smallpox had been eradicated from the Ivory Coast and 1.5 years after the last case of smallpox was detected in West and Central Africa. Clinical, serological, and epidemiological evidence indicated this disease was probably monkeypox, a poxvirus of the variola/vaccina subgroup. A serologic survey of poxvirus antibodies in the wild animal population detected neutralizing antibodies in rodents, larger mammals, primates, and birds. The laboratory and ecological characteristics of poxviruses require further elucidation, especially those which have been found in animals near human monkeypox cases.

Cost-effectiveness of the expanded programme on immunization in the Ivory Coast: a preliminary assessment.

A preliminary calculation was made of the cost-effectiveness of the measles component of the Expanded Programme on Immunization (EPI) in the Ivory Coast. The calculation is based on existing data (program budgets, coverage surveys, counts of vaccinations provided and subjective estimates) and applies to the first three demonstration and training zones (Abidjan, Abengourou and Korhogo) with a combined population of 1.75 million people. The average annual cost of the measles program (assumed to be 75% of all EPI costs, including supplies, personnel and equipment) in these three zones was $527,000 at 1980 prices. Having achieved an average coverage rate of 61%, the cost per vaccine was moderately high, $12. Yet, vaccinees are a sufficiently small part of the population that the cost per capita is only $0.30. The program is estimated to prevent 38,000 cases of measles and 1100 deaths per year in these three zones. Thus, the cost per measles case averted is $14, and the cost per death averted is $479. This means that the measles component of the EPI Program is highly effective in preventing deaths for the sums expended compared to many alternative health programs in developing countries.

[A broad program of vaccination in the Ivory Coast]. / Programme elargi de vaccination en Côte d'Ivoire.

This paper is a description of a vaccination programme against the most frequent communicable diseases among children: measles, tuberculosis, diphtheria, tetanus, whooping-cough and poliomyelitis. The programme is to be carried out in three different climate zones (town, forest and savanna) and over a period of six years. The project is supported by US-AID and UNICEF.

Evaluation of a measles-smallpox vaccination campaign by a sero-epidemiologic method.

An assessment technique has been devised whereby children from 30 randomly chosen sampling sites are visited within three days of measles-smallpox vaccination and one month later. Vaccination coverage is measured at house visits and immunologic status is determined by collection of early and late blood samples on filter papers from substratified children in priority age-groups, and by looking at vaccination scars. The methodology was employed in a rural area of the Ivory Coast during the maintenance phase of a measles-smallpox vaccination program; 1762 children from 0--72 months old were inspected. Children in the target age groups, 6--24 months, had a vaccination coverage of 53.6% whereas children outside of the target group had a 10.5% coverage. Of 571 target age children, 94.6% had a measles hemagglutination-inhibition antibody titer of less than 1:10 dilution at the first visit, and were presumed susceptible to measles or vaccine. Of 247 substratified children 6--8 months, 98.3% were susceptible to measles before vaccination; 84.3% of 127 vaccinated children in this age-group sero-converted when re-tested. Of 324 children 9--24 months, 91.7% were susceptible before the campaign; 94.7% of 170 vaccinated children in this age-group converted. A positive history of prior measles or prior measles-vaccination was not a good indicator of measles serologic status. The smallpox vaccination major reaction rate was 93.2%; 91.4% of children with a recent vaccination scar sero-converted to measles vaccine. Thus, the smallpox scar read at the second visit proved the best clinical marker for determining both coverage and immunologic effectiveness of the campaign.

Control of poliomyelitis in Africa.

In Africa, an estimated 168,000 children are disabled by poliomyelitis every year. With the use of lameness surveys to estimate incidence before immunization, surveys to measure vaccination coverage, and surveillance to monitor disease trends, poliomyelitis control in Yaound é, Cameroon; The Gambia; and Abidjan, Ivory Coast was examined. Three doses of oral poliovirus vaccine have been administered to 50%-70% of the children. The incidence of poliomyelitis has decreased significantly. Oral poliovirus vaccine administered during the first year of life has been effective in controlling poliomyelitis in tropical Africa.