| 1. |
- Cohen, Cheryl, et al.
(författare)
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Epidemiology of Viral-associated Acute Lower Respiratory Tract Infection Among Children < 5 Years of Age in a High HIV Prevalence Setting, South Africa, 2009-2012
- 2015
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Ingår i: The Pediatric Infectious Disease Journal. - 0891-3668 .- 1532-0987. ; 34:1, s. 66-72
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Tidskriftsartikel (refereegranskat)abstract
- Background: Data on the epidemiology of viral-associated acute lower respiratory tract infection (LRTI) from high HIV prevalence settings are limited. We aimed to describe LRTI hospitalizations among South African children aged < 5 years. Methods: We prospectively enrolled hospitalized children with physician-diagnosed LRTI from 5 sites in 4 provinces from 2009 to 2012. Using polymerase chain reaction (PCR), nasopharyngeal aspirates were tested for 10 viruses and blood for pneumococcal DNA. Incidence was estimated at 1 site with available population denominators. Results: We enrolled 8723 children aged < 5 years with LRTI, including 64% < 12 months. The case-fatality ratio was 2% (150/8512). HIV prevalence among tested children was 12% (705/5964). The overall prevalence of respiratory viruses identified was 78% (6517/8393), including 37% rhinovirus, 26% respiratory syncytial virus (RSV), 7% influenza and 5% human metapneumovirus. Four percent (253/6612) tested positive for pneumococcus. The annual incidence of LRTI hospitalization ranged from 2530 to 3173/100,000 population and was highest in infants (8446-10532/100,000). LRTI incidence was 1.1 to 3.0-fold greater in HIV-infected than HIV-uninfected children. In multivariable analysis, compared to HIV-uninfected children, HIV-infected children were more likely to require supplemental-oxygen [odds ratio (OR): 1.3, 95% confidence interval (CI): 1.1-1.7)], be hospitalized > 7 days (OR: 3.8, 95% CI: 2.8-5.0) and had a higher case-fatality ratio (OR: 4.2, 95% CI: 2.6-6.8). In multivariable analysis, HIV-infection (OR: 3.7, 95% CI: 2.2-6.1), pneumococcal coinfection (OR: 2.4, 95% CI: 1.1-5.6), mechanical ventilation (OR: 6.9, 95% CI: 2.7-17.6) and receipt of supplemental-oxygen (OR: 27.3, 95% CI: 13.2-55.9) were associated with death. Conclusions: HIV-infection was associated with an increased risk of LRTI hospitalization and death. A viral pathogen, commonly RSV, was identified in a high proportion of LRTI cases.
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| 2. |
- Madhi, Shabir A., et al.
(författare)
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Residual colonization by vaccine serotypes in rural South Africa four years following initiation of pneumococcal conjugate vaccine immunization
- 2020
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Ingår i: Expert Review of Vaccines. - : Taylor & Francis. - 1476-0584 .- 1744-8395. ; 19:4, s. 383-393
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Tidskriftsartikel (refereegranskat)abstract
- Background: We evaluated pneumococcal colonization in children and adults between the time of 7-valent pneumococcal conjugate vaccine (PCV) introduction in the immunization program in 2009 to two years after transitioning to PCV13 in 2011.Methods: Community-based carriage surveillance was undertaken between May-November 2013 (Period-3), with similar surveys in 2009 (Period-1) and 2011 (Period-2). Households with children below two years had a similar probability of being sampled in all surveys. Nasopharyngeal swabs were processed using standard methods and serotyped by Quellung.Results: In children>9-59 months old, overall pneumococcal colonization prevalence declined from 81.8% in Period-1 to 65.0% in Period-3 (p<0.001). Reductions of 70% (41.2% vs. 13.6%) in PCV7-serotypes colonization and 66% (15.3% vs. 4.4%) for the six additional PCV13-serotypes (PCV13-add6VT) were observed. There was, however, high residual colonization by PCV7-serotypes 19F (14.9% vs. 6.3%) and 23F (8.5% vs. 4.1%), despite reduction of 57% and 52%, respectively. Among individuals>12 years of age, there was 61% reduction in PCV7-serotype colonization (3.1% vs. 1.3%) and 75% decrease for PCV13-add6VT (2.1% vs. 0.6%) between Period-1 and Period-3.Conclusions: The residual prevalence of serotypes 19F and 23F, four years after introducing PCV in the South Africa, suggests ongoing community transmission and transient vaccine effects.
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| 3. |
- Nzenze, Susan A, et al.
(författare)
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Temporal changes in pneumococcal colonization in a rural African community with high HIV prevalence following routine infant pneumococcal immunization
- 2013
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Ingår i: The Pediatric Infectious Disease Journal. - : Ovid Technologies (Wolters Kluwer Health). - 0891-3668 .- 1532-0987. ; 32:11, s. 1270-1278
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Tidskriftsartikel (refereegranskat)abstract
- Background: Pneumococcal conjugate vaccine (PCV) immunization of children decreases their risk of nasopharyngeal acquisition of vaccine serotypes. We studied the impact of routine infant PCV immunization alone on the epidemiology of nasopharyngeal pneumococcal colonization among a rural African community with high prevalence of HIV positivity.Methods: Two cross-sectional surveys were undertaken in a rural South African community from May to October 2009 (period 1) and 2011 (period 2). Seven-valent PCV was introduced into the public immunization program for infants in April 2009, without catch-up campaign for older children. Randomly selected households with at least 1 child <2 years of age were recruited. Nasopharyngeal swabs from all consenting household members were obtained for Streptococcus pneumoniae culture and serotyping by Quellung method.Results: The median ages (SD) of children enrolled were 4.32 (SD, 3.4) and 3.80 (SD, 3.4) years in periods 1 and 2, respectively. Overall, the prevalence of vaccine serotype colonization declined from 18.3% (368/2010) in period 1 to 11.4% (418/3659) by period 2 (P < 0.0001). This included reductions (adjusted risk ratio) of 50% [95% confidence interval (95% CI): 0.42-0.59], 34% (95% CI: 0.48-0.92) and 64% (95% CI: 0.18-0.74) in age groups < 2 years, 6-12 years and adults. The prevalence of vaccine serotype colonization among primary caregivers decreased from 10.2% to 5.4% (P <= 0.001) by period 2. The prevalence of nonvaccine serotype colonization increased by 35% (95% CI: 1.17-1.56) among <2-year-old children by period 2, while it declined by 45-54% among adolescents and adults.Conclusions: An indirect effect of PCV7 was realized in a high HIV prevalence setting within 2 years of PCV introduction. The unexpected decline in nonvaccine serotypes colonization among adolescents/adults may indicate lag in replacement colonization by nonvaccine serotypes in this group.
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