Rubella in South Africa: An impending Greek tragedy?

Background. The incidence of congenital rubella syndrome (CRS) is unknown in South Africa. There is evidence that it may be significant and largely undetected, particularly in the upper socio-economic group. This may be due to incomplete routine administration of MMR vaccine in infancy and a build-up of susceptible females reaching the childbearing age group who could be exposed to the extensive reservoir of virus in the unimmunised public sector of the population.Objective. To assess the extent of the immunity gap to rubella by testing for protective IgG antibodies and the incidence of rubella infection by testing for IgM antibodies in sera. The data obtained would also be used to model the extent of CRS.Design. Residual laboratory serum specimens from public and private laboratories were serologically tested for rubella IgG antibodies to investigate the immunity gap in the population and IgM antibodies in sera collected from the measles rashlike illness surveillance programme. Modelling exercises calculated the force of infection and the predicted incidence of CRS in South Africa.Results. The serological immunity gap was significantly greater in the private sector specimens compared with the public sector – 10.7% versus 5.4%, respectively. In most years rubella caused much more rash-like illness than measles, with a significant number (5.1 - 9.6%) of rubella-positive IgM specimens occurring in women of childbearing age.Conclusion. Modelling of the data suggests that the extent of CRS may be grossly underestimated in South Africa. Approximately 654 cases are calculated to occur every year. It is suggested that selective immunisation of girls before puberty should be instituted together with a routine rubella immunisation programme of infants to forestall a possible future outbreak of CRS, as occurred in Greece in 1993

The epidemiology of respiratory syncytial virus (RSV) infections in South African children

Objectives. To review the incidence, outcomes and risk factors associated with respiratory syncytial virus (RSV) infection in South African children.Design. Review of published literature and laboratory records.Methods. Review of the published literature. Articles listed on MEDLINE with 'South African' or 'children' and 'respiratory syncytial virus' or 'acute respiratory tract infections' as text words were retrieved. We analysed the data on respiratory virus activity from January 1990 to June 1996. Data were obtained from the National Institute for Virology database, which includes information on viral respiratory infections from the seven academic virology departments in South Africa.Results. Acute respiratory tract infections cause approximately 8% of all deaths in the under-5 age group in South Africa. The published hospital-based incidence of RSV infection varies from 3% to 18%. Mortality rates in these studies were between 12% and 43%. Risk factors identified for severe RSV infection requiring hospitalisation were malnutrition, prematurity, age < 6 months, vitamin A deficiency, environmental pollution and congenital heart disease. There is a seasonal peak in RSV cases, with the majority occurring in winter.Conclusions. Acute respiratory tract infections and RSV infections are an important cause of mortality and morbidity in young children in South Africa. However, currently available information from laboratory records and published South African literature is not sufficient to assess the impact of this infection. Age-specific incidence data in the 0 - 5-year age group are essential for the rational planning and implementation of future vaccine strategies, public health interventions and treatment of RSV infections

Evaluation of Two Influenza Surveillance Systems in South Africa

<div><p>Background</p><p>The World Health Organisation recommends outpatient influenza-like illness (ILI) and inpatient severe acute respiratory illness (SARI) surveillance. We evaluated two influenza surveillance systems in South Africa: one for ILI and another for SARI.</p><p>Methodology</p><p>The Viral Watch (VW) programme has collected virological influenza surveillance data voluntarily from patients with ILI since 1984 in private and public clinics in all 9 South African provinces. The SARI surveillance programme has collected epidemiological and virological influenza surveillance data since 2009 in public hospitals in 4 provinces by dedicated personnel. We compared nine surveillance system attributes from 2009–2012.</p><p>Results</p><p>We analysed data from 18,293 SARI patients and 9,104 ILI patients. The annual proportion of samples testing positive for influenza was higher for VW (mean 41%) than SARI (mean 8%) and generally exceeded the seasonal threshold from May to September (VW: weeks 21–40; SARI: weeks 23–39). Data quality was a major strength of SARI (most data completion measures >90%; adherence to definitions: 88–89%) and a relative weakness of the VW programme (62% of forms complete, with limited epidemiologic data collected; adherence to definitions: 65–82%). Timeliness was a relative strength of both systems (e.g. both collected >93% of all respiratory specimens within 7 days of symptom onset). ILI surveillance was more nationally representative, financially sustainable and expandable than the SARI system. Though the SARI programme is not nationally representative, the high quality and detail of SARI data collection sheds light on the local burden and epidemiology of severe influenza-associated disease.</p><p>Conclusions</p><p>To best monitor influenza in South Africa, we propose that both ILI and SARI should be under surveillance. Improving ILI surveillance will require better quality and more systematic data collection, and SARI surveillance should be expanded to be more nationally representative, even if this requires scaling back on information gathered.</p></div

Characteristics of the Viral Watch and severe acute respiratory infection (SARI) surveillance programmes.

<p>* Most sentinel sites consist of private sector general practitioners, though primary care clinics, paediatric outpatient departments, and occupational health clinics are also included.</p><p>Characteristics of the Viral Watch and severe acute respiratory infection (SARI) surveillance programmes.</p