Pneumococcal conjugate vaccine--a health priority.
ABSTRACT Pneumonia is a major cause of childhood mortality and morbidity. Streptococcus pneumoniae is the most important bacterial pathogen causing pneumonia in children. The HIV epidemic has increased the burden and severity of childhood pneumococcal pneumonia and invasive disease fortyfold. Pneumococcal conjugate vaccine (PCV) is a highly effective intervention to reduce invasive pneumococcal disease and pneumonia. Studies evaluating a 9-valent PCV in South Africa and The Gambia reported a 72 - 77% reduction in vaccine-serotype-specific invasive disease in vaccinated children. As many of the pneumococcal serotypes associated with antibiotic resistance are included in PCV, vaccination has also been associated with a reduction in antimicrobial-resistant invasive disease. PCV may also reduce childhood mortality, especially in places with limited access to health care, as shown in Gambian study in which PCV reduced childhood mortality by 16%. In addition to the direct effects of PCV, there is a substantial reduction in disease burden through indirect protection of non-vaccinated populations. PCV is immunogenic in HIV-infected children and provides protection against invasive disease or pneumonia in a substantial number of children. Although the efficacy of PCV for prevention of invasive disease or pneumonia is lower in HIV-infected compared to -uninfected children, the overall burden of disease prevented is much greater in HIV-infected children because of the higher burden of pneumococcal disease in these children. Consequently, vaccine-preventable invasive disease is almost 60 times higher in HIV-infected compared to -uninfected children, while the reduction in pneumonia in HIV-infected children is 15 times greater. However, the long-term efficacy of PCV wanes in HIV-infected children who are not taking antiretroviral therapy, and booster doses are probably indicated. Although there is concern about the potential for replacement disease due to non-vaccine serotypes, a substantial and sustained reduction in invasive disease has occurred overall in populations with widespread childhood immunisation. Routine childhood immunisation is now the standard of care in most developed countries. However, PCV is much less accessible to children in developing countries due to cost and availability. Cost-effectiveness analysis indicates that use of PCV is potentially highly cost-effective, at tiered pricing, even in very low-income countries. Widespread availability and vaccination with PCV is urgently needed for all children under 2 years of age in South Africa. In addition, the use of PCV for all HIV-infected children under 9 years should be prioritised.
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ABSTRACT: Although antiretroviral treatment (ART) has reduced the incidence of HIV-related opportunistic infections among children living with HIV, access to ART remains limited for children, especially in resource-limited settings. This paper reviews current knowledge on the contribution of opportunistic infections and common childhood illnesses to morbidity and mortality in children living with HIV, highlights interventions known to improve the health of children, and identifies research gaps for further exploration. Literature review of peer-reviewed articles and abstracts combined with expert opinion and operational experience. Morbidity and mortality due to opportunistic infections has decreased in both developed and resource-limited countries. However, the burden of HIV-related infections remains high, especially in sub-Saharan Africa, where the majority of HIV-infected children live. Limitations in diagnostic capacity in resource-limited settings have resulted in a relative paucity of data on opportunistic infections in children. Additionally, the reliance on clinical diagnosis means that opportunistic infections are often confused with common childhood illnesseswhich also contribute to excess morbidity and mortality in these children. Although several preventive interventions have been shown to decrease opportunistic infection-related mortality, implementation of many of these interventions remains inconsistent. In order to reduce opportunistic infection-related mortality, early ART must be expanded, training for front-line clinicians must be improved, and additional research is needed to improve screening and diagnostic algorithms.AIDS (London, England) 11/2013; 27 Suppl 2:S159-67. DOI:10.1097/QAD.0000000000000080 · 6.56 Impact Factor
Article: Private practice: adapt or die.South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde 01/2009; 99(12):836. · 1.71 Impact Factor
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ABSTRACT: A description of invasive Streptococcus pneumoniae isolates over a 5-year period from blood culture and cerebrospinal fluid culture follows, in Pretoria South Africa January 2005 through December 2009. Isolates were identified using standard microbiological techniques, serotyped, and a MIC determined for penicillin and cefotaxime. A total of 177 isolates were included in the analysis. Eighty percent of patients in the 18- to 45-year age group tested positive for HIV. In children <5 years of age, 66% (n = 49) of serotypes were those present in the heptavalent pneumococcal conjugate vaccine (PCV-7). Fifty-nine percent (n = 29) were from PCV-7 serotypes in the <1-year-old age group. An additional peak of invasive disease was also seen in the 18- to 45-year age group. Only 1 of 177 isolates had resistance to penicillin (MIC ≥2 μg/mL); none was resistant to cefotaxime. The introduction of the PCV-7 vaccine in South Africa will decrease invasive pneumococcal disease caused by vaccine serotypes.Diagnostic microbiology and infectious disease 09/2011; 71(3):309-11. DOI:10.1016/j.diagmicrobio.2011.07.006 · 2.57 Impact Factor