Effectiveness of pneumococcal conjugate vaccine and rotavirus vaccine introduction into the South African public immunisation programme
ABSTRACT Immunisation has contributed greatly to the control of vaccine-preventable diseases and therefore to improvements in health and survival, especially among young children, and remains one of the most successful and cost-effective public health interventions. This remains true for many of the newer, more expensive vaccines. Vaccines against invasive pneumococcal disease and rotavirus infection were introduced into the South African Expanded Programme on Immunization in April 2009. This article describes the rationale for and process of the introduction of these two vaccines, pneumococcal conjugate vaccine and rotavirus vaccine. It also aims to evaluate the success of and challenges related to their introduction, in terms of both achieving universal coverage and improving survival and health in South African children.
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ABSTRACT: Introduction Little is known about the molecular epidemiology of deafness in sub-Saharan Africa (SSA). Even in Nigeria, the most populous African nation, no genetic studies of deafness have been conducted. This pioneering work aims at investigating the frequencies of gene mutations relatively common in other parts of the world (i.e. those in GJB2, GJB6, and mitochondrial DNA) among subjects from Nigeria with hearing loss (HL) with no evidence of acquired pathology or syndromic findings. In addition, we review the literature on the genetics of deafness in SSA. Method We evaluated 81 unrelated deaf probands from the Yoruba tribe residing in Ibadan, a suburban city in Nigeria, for the etiology of their deafness. Subjects underwent genetic testing if their history was negative for an environmental cause and physical examination did not find evidence of a syndrome. Both exons of GJB2 and mitochondrial DNA flanking the 1555A > G mutation were PCR-amplified followed by Sanger sequencing. GJB6 deletions were screened via quantitative PCR. Result We identified 44 probands who had nonsyndromic deafness with no environmental cause. The age at study time ranged between 8 months and 45 years (mean = 24 years) and age at onset was congenital or prelingual (<age 2 years) in 37 (84%) probands and postlingual in 7 (16%) probands. Among these, 35 probands were the only affected members of their families (simplex cases), while there were at least two affected family members in 9 cases (multiplex). Molecular analyses did not show a pathogenic variant in any one of the 44 probands studied. Conclusion GJB2, GJB6 and mitochondrial DNA 1555A > G mutations were not found among this initial cohort of the deaf in Nigeria. This makes imperative the search for other genes in the etiology of HL in this population.International Journal of Pediatric Otorhinolaryngology 08/2014; 78(11). DOI:10.1016/j.ijporl.2014.08.014 · 1.32 Impact Factor
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ABSTRACT: Background The effectiveness of the rotavirus vaccine under conditions of routine use in an African setting with a high prevalence of HIV infection needs to be established. We assessed the vaccine effectiveness of monovalent human rotavirus vaccine in preventing admission to hospital for acute rotavirus diarrhoea, after its introduction at age 6 and 14 weeks into South Africa's national immunisation programme. Methods This case-control study was done at seven hospitals in South Africa between April 19, 2010, and Oct 31, 2012. The hospitals were located in a range of urban, peri-urban, and rural settings, with varying rates of population HIV infection. Cases were children aged from 18 weeks to 23 months who were age-eligible to have received at least one dose of the human rotavirus vaccine (ie, those born after June 14, 2009) admitted to hospital with laboratory-confirmed acute rotavirus diarrhoea, and the primary control group was children admitted to hospital with diarrhoea testing negative for rotavirus. A second control group comprised children admitted to a subset of three of the seven hospitals with respiratory illness. The primary endpoint was adjusted vaccine effectiveness (1 – adjusted odds ratio × 100%) in children aged from 18 weeks to 23 months and was calculated by unconditional logistic regression. This study is registered on the South African National Clinical Trial Register, number DOH-27-0512-3247. Findings Of 540 rotavirus-positive cases, 278 children (52%) received two doses, 126 (23%) one dose, and 136 (25%) no doses of human rotavirus vaccine, compared with 1434 rotavirus-negative controls of whom 856 (60%) received two doses, 334 (23%) one dose, and 244 (17%) no doses. Adjusted vaccine effectiveness using rotavirus-negative controls was 57% (95% CI 40–68) for two doses and 40% (16–57) for one dose; estimates were similar when respiratory controls were used as the control group. Adjusted vaccine effectiveness for two doses was similar between age groups 18 weeks–11 months (54%, 95% CI 32–68) and 12–23 months (61%, 35–77), and was similar in HIV-exposed-uninfected (64%, 95% CI 34–80) and HIV-unexposed-uninfected children (54%, 31–69). Interpretation Human rotavirus vaccine provided sustained protection against admission to hospital for acute rotavirus diarrhoea during the first and second years of life. This finding is encouraging and establishes the public health value of rotavirus vaccine in an African setting, especially as rotavirus vaccines are introduced into an increasing number of African countries. Funding GAVI Alliance (with support from PATH).The Lancet Infectious Diseases 10/2014; 14(11). DOI:10.1016/S1473-3099(14)70940-5 · 19.45 Impact Factor