The urban poor constitute a rapidly increasing proportion of the population in developing countries. Focusing attention on underserved urban slums and squatter settlements will contribute greatly to immunization programme goals, because these areas account for 30-50% of urban populations, usually provide low access to health services, carry a large burden of disease mortality, and act as sources of infection for the city and surrounding rural areas. Improvement of urban immunization programmes requires intersectorial collaboration, use of all opportunities to vaccinate eligible children and mothers, identification of low-coverage neighbourhoods and execution of extra activities in these neighbourhoods, and community mobilization to identify and refer persons for vaccination. Improved disease surveillance helps to identify high-risk populations and document programme impact. New developments in vaccines, such as the high-dose Edmonston-Zagreb vaccine, will allow changes in the immunization schedule that facilitate the control of specific diseases. Finally, operational research can assist managers to conduct urban situation assessments, evaluate programme performance at the "micro" level, and design and monitor interventions.
PIP: Their high birth rate, crowded living conditions, and continuous influx of rural migrants make urban slums and squatter settlements an important focus for immunization campaigns in Africa. Such areas include 30-50% of Africa's urban populations, but are generally excluded from access to clinically oriented health services. To obtain vaccination, poor urban families must make special trips to primary health care centers were there is minimal communication between staff and the community. If coverage with measles vaccine in Africa is to increase from the 1988 level of 45%, specific plans of action must be developed for large urban areas. Given the multifaceted problems inherent in urban health programs, an intersectoral approach is necessary. An effort should be made in existing health facilities to use any contact with eligible children and mothers as an opportunity to immunize. To reduce waiting times, immunization centers can be established in clinics. The routine collection of data on immunization coverage can be used to identify pockets of low coverage; where available, disease surveillance data can pinpoint high-risk neighborhoods. Increased accessibility of vaccination must be accompanied by efforts to promote community motivation and ensure that children complete the vaccination series. Household visits aimed at registering eligible individuals and tracing defaulters are useful. Finally, a sentinel surveillance system can provide important information on the geographic distribution of measles, the most affected age groups, transmission patterns, risk factors for disease, and vaccine efficacy.