BACKGROUND: The World Health Organization (WHO) recommended the use of high titre measles vaccine in 1989. Subsequent long term follow-up of several trials yielded results suggesting higher mortality among children inoculated with medium and high titre vaccines compared to standard titre vaccines, although none of the individual trials found significant differences in mortality. METHODS: Long term survival after standard, medium and high titre measles vaccines has been investigated in a combined analysis of all West African trials with mortality data. In trials from Guinea-Bissau, The Gambia and Senegal, children received medium or high titre vaccines from 4 months of age and were compared to control groups recruited at the same time later receiving standard titre vaccine from 9 months of age. All children were followed up to at least 3 years old. RESULTS: Combining trials of high titre vaccines showed higher mortality among the high titre group compared to the standard group: mortality ratio (MR) = 1.33 (95% CI : 1.02-1. 73). Mortality among recipients of medium titre vaccines was not different from that in the standard vaccine group, MR = 1.11 (95% CI: 0.54-2.27). In a combined analysis by sex, the adjusted mortality ratios comparing high titre vaccine with standard vaccine were 1.86 (95% CI : 1.28-2.70) for females and 0.91 (95% CI : 0.61-1.35) for males. The trials were not designed to study long term mortality. Adjustments for several possible sources of bias did not alter the results. CONCLUSIONS: The combined analysis showed a decreased survival related to high titre measles vaccine compared with standard titre vaccines, though solely among females. As a result of these studies from West Africa and a study from Haiti, WHO has recommended that high titre measles vaccine no longer be used.
BACKGROUND: The World Health Organization (WHO) recommended the use of high titre measles vaccine in 1989. Subsequent long term follow-up of several trials yielded results suggesting higher mortality among children inoculated with medium and high titre vaccines compared to standard titre vaccines, although none of the individual trials found significant differences in mortality. METHODS: Long term survival after standard, medium and high titre measles vaccines has been investigated in a combined analysis of all West African trials with mortality data. In trials from Guinea-Bissau, The Gambia and Senegal, children received medium or high titre vaccines from 4 months of age and were compared to control groups recruited at the same time later receiving standard titre vaccine from 9 months of age. All children were followed up to at least 3 years old. RESULTS: Combining trials of high titre vaccines showed higher mortality among the high titre group compared to the standard group: mortality ratio (MR) = 1.33 (95% CI : 1.02-1. 73). Mortality among recipients of medium titre vaccines was not different from that in the standard vaccine group, MR = 1.11 (95% CI: 0.54-2.27). In a combined analysis by sex, the adjusted mortality ratios comparing high titre vaccine with standard vaccine were 1.86 (95% CI : 1.28-2.70) for females and 0.91 (95% CI : 0.61-1.35) for males. The trials were not designed to study long term mortality. Adjustments for several possible sources of bias did not alter the results. CONCLUSIONS: The combined analysis showed a decreased survival related to high titre measles vaccine compared with standard titre vaccines, though solely among females. As a result of these studies from West Africa and a study from Haiti, WHO has recommended that high titre measles vaccine no longer be used.
Entities:
Keywords:
Africa; Africa South Of The Sahara; Child Health; Child Health Services; Child Mortality; Child Survival; Comparative Studies; Delivery Of Health Care; Demographic Factors; Developing Countries; Diseases; English Speaking Africa; French Speaking Africa; Gambia; Guinea-bissau; Health; Health Services; Immunization; Length Of Life; Maternal-child Health Services; Measles--prevention and control; Mortality; Population; Population Characteristics; Population Dynamics; Portuguese Speaking Africa; Primary Health Care; Research Methodology; Research Report; Senegal; Sex Factors; Studies; Survivorship; Vaccines; Viral Diseases; Western Africa
Authors: Chien-Hsiung Pan; Catherine E Greer; Debra Hauer; Harold S Legg; Eun-Young Lee; M Jeff Bergen; Brandyn Lau; Robert J Adams; John M Polo; Diane E Griffin Journal: J Virol Date: 2010-02-03 Impact factor: 5.103
Authors: Chien-Hsiung Pan; Nitya Nair; Robert J Adams; M Christine Zink; Eun-Young Lee; Fernando P Polack; Manmohan Singh; Derek T O'Hagan; Diane E Griffin Journal: Clin Vaccine Immunol Date: 2008-02-20
Authors: M Jeff Bergen; Chien-Hsiung Pan; Catherine E Greer; Harold S Legg; John M Polo; Diane E Griffin Journal: PLoS One Date: 2010-04-22 Impact factor: 3.240
Authors: Peter Aaby; Cesário L Martins; May-Lill Garly; Carlito Balé; Andreas Andersen; Amabelia Rodrigues; Henrik Ravn; Ida M Lisse; Christine S Benn; Hilton C Whittle Journal: BMJ Date: 2010-11-30
Authors: Adam Edvin Roth; Christine Stabell Benn; Henrik Ravn; Amabelia Rodrigues; Ida Maria Lisse; Maria Yazdanbakhsh; Hilton Whittle; Peter Aaby Journal: BMJ Date: 2010-03-15