Congenital Rubella Syndrome Surveillance in South Africa Using a Sentinel Site Approach: A Cross-sectional Study.

BACKGROUND: Congenital rubella syndrome (CRS) includes disorders associated with intrauterine rubella infection. Incidence of CRS is higher in countries with no rubella-containing vaccines (RCV) in their immunization schedules. In the World Health Organization African region, RCVs are being introduced as part of the 2012-2020 global measles and rubella strategic plan. This study aimed to describe the epidemiology of confirmed CRS in South Africa prior to introduction of RCVs in the immunization schedule. METHODS: This was a descriptive study with 28 sentinel sites reporting laboratory-confirmed CRS cases in all 9 provinces of South Africa. In the retrospective phase (2010 to 2014), CRS cases were retrieved from medical records, and in the prospective phase (2015 to 2017) clinicians at study sites reported CRS cases monthly. RESULTS: There were 42 confirmed CRS cases in the retrospective phase and 53 confirmed CRS cases in the prospective phase. Most frequently reported birth defects were congenital heart disease and cataracts. The median age of mothers of CRS cases was 21 years in the retrospective phase (range: 11 to 38 years) and 22 years in the prospective phase (range: 15 to 38 years). CONCLUSION: Baseline data on laboratory-confirmed CRS will enable planning and monitoring of RCV implementation in the South African Expanded Programme on Immunization program. Ninety-eight percent of mothers of infants with CRS were young women 14-30 years old, indicating a potential immunity gap in this age group for consideration during introduction of RCV.

Effectiveness of 7-valent pneumococcal conjugate vaccine against invasive pneumococcal disease in HIV-infected and -uninfected children in south africa: a matched case-control study.

BACKGROUND: South Africa introduced 7-valent pneumococcal conjugate vaccine (PCV7) in April 2009 using a 2 + 1 schedule (6 and 14 weeks and 9 months). We estimated the effectiveness of ≥2 PCV7 doses against invasive pneumococcal disease (IPD) in human immunodeficiency virus (HIV)-infected and -uninfected children. METHODS: IPD (pneumococcus identified from a normally sterile site) cases were identified through national laboratory-based surveillance. Specimens were serotyped by Quellung or polymerase chain reaction. Four controls, matched for age, HIV status, and hospital were sought for each case. Using conditional logistic regression, we calculated vaccine effectiveness (VE) as 1 minus the adjusted odds ratio for vaccination. RESULTS: From March 2010 through November 2012, we enrolled 187 HIV-uninfected (48 [26%] vaccine serotype) and 109 HIV-infected (43 [39%] vaccine serotype) cases and 752 HIV-uninfected and 347 HIV-infected controls aged ≥16 weeks. Effectiveness of ≥2 PCV7 doses against vaccine-serotype IPD was 74% (95% confidence interval [CI], 25%-91%) among HIV-uninfected and -12% (95% CI, -449% to 77%) among HIV-infected children. Effectiveness of ≥3 doses against vaccine-serotype IPD was 90% (95% CI, 14%-99%) among HIV-uninfected and 57% (95% CI, -371% to 96%) among HIV-infected children. Among HIV-exposed but -uninfected children, effectiveness of ≥2 doses was 92% (95% CI, 47%-99%) against vaccine-serotype IPD. Effectiveness of ≥2 doses against all-serotype multidrug-resistant IPD was 96% (95% CI, 62%-100%) among HIV-uninfected children. CONCLUSIONS: A 2 + 1 PCV7 schedule was effective in preventing vaccine-serotype IPD in HIV-uninfected and HIV-exposed, uninfected children. This finding supports the World Health Organization recommendation for this schedule as an alternative to a 3-dose primary series among HIV-uninfected individuals.

Co-morbidities in children presenting with chronic suppurative otitis media--a South African study.

BACKGROUND: Chronic suppurative otitis media (CSOM) is common among children in southern Africa. Managing associated co-morbidities may result in earlier disease resolution. METHODS: Children <13 years of age with otorrhoea lasting >4 weeks were recruited to the study. Each child underwent a full clinical examination, a blood count, an HIV test and CD4 cell count, if found to be infected. RESULTS: The study included 86 children, and the median age was 4.6 years. HIV infection was present in 45 of 83 children (54.2%), of which 23 (51.1%) were receiving antiretroviral treatment at the time of presentation. Underweight was present in 22 of 85 (25.9%) children and in 17 of the 45 (37.8%) HIV-infected children. One or more clinical signs (not aural-related) were found in 46 of 86 (53.4%) children. Cholesteatoma was found in 23 of 113 (20.4%) ears, and 9 of 86 (10.5%) children had serious associated aural or intracranial complications. CONCLUSIONS: A high percentage of children with CSOM have associated pathology that needs to be diagnosed to optimally manage CSOM.

Whole genome molecular analysis of respiratory syncytial virus pre and during the Covid-19 pandemic in free state province, South Africa.

Respiratory syncytial virus (RSV) is the most predominant viral pathogen worldwide in children with lower respiratory tract infections. The Coronavirus disease 2019 (COVID-19) pandemic and resulting nonpharmaceutical interventions perturbed the transmission pattern of respiratory pathogens in South Africa. A seasonality shift and RSV resurgence was observed in 2020 and 2021, with several infected children observed. Conventional RSV-positive nasopharyngeal swabs were collected from various hospitals in the Free State province, Bloemfontein, South Africa, from children suffering from respiratory distress and severe acute respiratory infection between 2020 to 2021. Overlapping genome fragments were amplified and complete genomes were sequenced using the Illumina MiSeq platform. Maximum likelihood phylogenetic and evolutionary analysis were performed on both RSV-A/-B G-genes with published reference sequences from GISAID and GenBank. Our study strains belonged to the RSV-A GA2.3.2 and RSV-B GB5.0.5a clades. The upsurge of RSV was due to pre-existing strains that predominated in South Africa and circulating globally also driving these off-season RSV outbreaks during the COVID-19 pandemic. The variants responsible for the resurgence were phylogenetically related to pre-pandemic strains and could have contributed to the immune debt resulting from pandemic imposed restrictions. The deviation of the RSV season from the usual pattern affected by the COVID-19 pandemic highlights the need for ongoing genomic surveillance and the identification of genetic variants to prevent unforeseen outbreaks in the future.

Effectiveness of the 13-valent pneumococcal conjugate vaccine against invasive pneumococcal disease in South African children: a case-control study.

BACKGROUND: The 13-valent pneumococcal conjugate vaccine (PCV13) was designed to include disease-causing serotypes that are important in low-income and middle-income countries. Vaccine effectiveness estimates are scarce in these settings. South Africa replaced PCV7 with PCV13 in 2011 using a 2 + 1 schedule. We aimed to assess the effectiveness of two or more doses of PCV13 against invasive pneumococcal disease in children with HIV infection and in those not infected with HIV. METHODS: Cases of invasive pneumococcal disease in children aged 5 years or younger were identified through national laboratory-based surveillance. Isolates were serotyped with the Quellung reaction or PCR. We sought in-hospital controls for every case, matched for age, HIV status, and study site. We aimed to enrol four controls for every case not infected with HIV and six controls for every case with HIV infection (case-control sets). With conditional logistic regression, we calculated vaccine effectiveness as a percentage, with the equation 1 - [adjusted odds ratio for vaccination] × 100. We included data from an earlier investigation of PCV7 to assess vaccine effectiveness in children exposed to but not infected with HIV and in malnourished children not infected with HIV. FINDINGS: Between January, 2012, and December, 2014, we enrolled children aged 16 weeks or older to our study: 240 were cases not infected with HIV, 75 were cases with HIV infection, 1118 were controls not infected with HIV, and 283 were controls with HIV infection. The effectiveness of two or more doses of PCV13 against PCV13-serotype invasive pneumococcal disease was 85% (95% CI 37 to 96) among 11 case-control sets of children not infected with HIV and 91% (-35 to 100) among three case-control sets of children with HIV infection. PCV13 effectiveness among 26 case-control sets of children not infected with HIV was 52% (95% CI -12 to 79) against all-serotype invasive pneumococcal disease and 94% (44 to 100) for serotype 19A. Vaccine effectiveness against PCV7-serotype invasive pneumococcal disease was 87% (95% CI 38 to 97) in children exposed to HIV but uninfected and 90% (53 to 98) in malnourished children not infected with HIV. INTERPRETATION: Our results indicate that PCV13 in a 2 + 1 schedule is effective for preventing vaccine-type pneumococcal infections in young children not infected with HIV, including those who are malnourished or who have been exposed to HIV. Although the point estimate for PCV13 vaccine effectiveness in children infected with HIV was high, it did not reach significance, possibly because of the small sample size. These findings support recommendations for widespread use of pneumococcal conjugate vaccine in low-income and middle-income countries. FUNDING: Gavi, The Vaccine Alliance.

Risk factors for invasive pneumococcal disease among children less than 5 years of age in a high HIV prevalence setting, South Africa, 2010 to 2012.

BACKGROUND: Invasive pneumococcal disease (IPD) causes significant disease burden, especially in developing countries, even in the era of pneumococcal conjugate vaccine and maternal-to-child HIV transmission prevention programs. We evaluated factors that might increase IPD risk in young children in a high HIV prevalence setting. METHODS: We conducted a case-control study using IPD cases identified at 24 Group for Enteric, Respiratory and Meningeal disease Surveillance-South Africa program sites (2010-2012). At least 4 controls were matched by age, HIV status and hospital to each case. Potential risk factors were evaluated using multivariable conditional logistic regression. RESULTS: In total, 486 age-eligible cases were enrolled. Factors associated with IPD in HIV-uninfected children (237 cases, 928 controls) included siblings <5 years [adjusted odds ratio (aOR) = 1.68, 95% confidence interval (CI): 1.16-2.46], underlying medical conditions (aOR = 1.99, CI 1.22-3.22), preceding upper respiratory tract infection (aOR = 1.79, CI 1.19-2.69), day-care attendance (aOR = 1.58, CI 1.01-2.47), perinatal HIV exposure (aOR = 1.62, CI 1.10-2.37), household car ownership (aOR = 0.45, CI 0.25-0.83) and ≥2 7-valent pneumococcal conjugate vaccine doses (aOR = 0.67, CI 0.46-0.99). Among HIV-infected children (124 cases, 394 controls), IPD-associated factors included malnutrition (aOR = 2.68, CI 1.40-5.14), upper respiratory tract infection (aOR = 3.49, CI 1.73-7.03), tuberculosis in the last 3 months (aOR = 5.12, CI 1.69-15.50) and current antiretroviral treatment (aOR = 0.13, CI 0.05-0.38). CONCLUSION: Previously identified factors related to poverty, poor health and intense exposure continue to be risk factors for IPD in children. Ensuring delivery of pneumococcal conjugate vaccine and antiretroviral treatment are important for improving disease prevention.