Maintaining high rates of measles immunization in Africa

• Published in: Epidemiology and infection Vol. 139; no. 7; pp. 1039 - 1049
• Main Authors: LESSLER, J., MOSS, W. J., LOWTHER, S. A., CUMMINGS, D. A. T.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01-07-2011
• Subjects: Age Factors; Antibodies; Antibodies, Viral - immunology; Applied microbiology; Biological and medical sciences; Child, Preschool; Childhood infections; Children; Children & youth; Cross-Sectional Studies; Data collection; Disease transmission; Dosage; Fundamental and applied biological sciences. Psychology; Human subjects; Human viral diseases; Humans; Immunity; Immunization; Immunization Programs - methods; Immunization Programs - statistics & numerical data; Immunization Schedule; Infant; Infectious diseases; Measles; Measles - immunology; Measles - prevention & control; Measles Vaccine - therapeutic use; Measles vaccines; Measles virus; Measles virus - immunology; Medical sciences; Microbiology; Surveys and Questionnaires; Vaccination; Vaccines; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies (general aspects); Viral diseases; Viral diseases with cutaneous or mucosal lesions and viral diseases of the eye; Zambia - epidemiology; Africa; Zambia; vaccination (immunization); Measles (rubeola); Infection; Immunization; Vaccine; Epidemiology; Viral disease; Measles
• ISSN: 0950-2688; 1469-4409
• DOI: 10.1017/S0950268810002232

Supplementary immunization activities (SIAs) are important in achieving high levels of population immunity to measles virus. Using data from a 2006 survey of measles vaccination in Lusaka, Zambia, we developed a model to predict measles immunity following routine vaccination and SIAs, and absent natural infection. Projected population immunity was compared between the current programme and alternatives, including supplementing routine vaccination with a second dose, or SIAs at 1-, 2-, 3-, 4- and 5-year intervals. Current routine vaccination plus frequent SIAs could maintain high levels of population immunity in children aged <5 years, even if each frequent SIA has low coverage (e.g. ⩾72% for bi-annual 60% coverage SIAs vs. ⩾69% for quadrennial 95% coverage SIAs). A second dose at 12 months with current coverage could achieve 81% immunity. Circulating measles virus will only increase population immunity. Public health officials should consider frequent SIAs when resources for a two-dose strategy are unavailable.