Prevalence and trends of staphylococcus aureus bacteraemia in hospitalized patients in South Africa, 2010 to 2012: laboratory-based surveillance mapping of antimicrobial resistance and molecular epidemiology.

CAPRISA, 2015.Abstract available in pdf

Hospital-associated methicillin-resistant Staphylococcus aureus: A cross-sectional analysis of risk factors in South African tertiary public hospitals.

Hospital-associated methicillin-resistant S. aureus (HA-MRSA) remains a significant cause of morbidity and mortality worldwide. We conducted a study to determine risk factors for HA-MRSA in order to inform control strategies in South Africa.We used surveillance data collected from five tertiary hospitals in Gauteng and Western Cape provinces during 2014 for analysis. A case of HA-MRSA was defined as isolation of MRSA from a blood culture 48 hours after admission and/or if the patient was hospitalised in the six months prior to the current culture. Multivariable logistic regression modelling was used to determine risk factors for HA-MRSA.Of the 9971 patients with positive blood cultures, 7.7% (772) had S. aureus bacteraemia (SAB). The overall prevalence of MRSA among those with SAB was 30.9% (231/747; 95% confidence interval [CI] 27.6%- 34.3%). HA-MRSA infections accounted for 28.3% of patients with SAB (207/731; 95% CI 25.1%- 31.7%). Burns (adjusted odds ratio [aOR] 12.7; 95% CI 4.7-34.4), age ≤1 month (aOR 8.7; 95% CI 3.0-24.6), residency at a long-term care facility (aOR 5.2; 95% CI, 1.5-17.4), antibiotic use within two months of the current SAB episode (aOR 5.1; 95% CI 2.8-9.1), hospital stay of 13 days or more (aOR 2.8; 95% CI 1.3-5.6) and mechanical ventilation (aOR 2.2; 95% CI 1.07-4.6), were independent risk factors for HA-MRSA infection.The prevalence of MRSA remains high in South African tertiary public hospitals. Several identified risk factors of HA-MRSA infections should be considered when instituting infection and prevention strategies in public-sector hospitals, including intensifying the implementation of antimicrobial stewardship programmes. There is an urgent need to strengthen infection prevention and control in burn wards, neonatal wards, and intensive care units which house mechanically ventilated patients

Respiratory Health in a Community Living in Close Proximity to Gold Mine Waste Dumps, Johannesburg, South Africa

The effects on respiratory health in populations living close to silica-rich gold mine dumps are unknown. This pilot study related respiratory health and exposure to mine dump dust using two measures of exposure: exposure group, based on distance lived from the mine dump—high (n = 93) (home <500 m from a mine dump), moderate (n = 133) (500–1.5 km), and low (n = 84) (>15 km, control group); and cumulative exposure index (CEI) derived from exposure group and number of years of residence in each exposure group. Participants were interviewed about respiratory symptoms and had chest X-rays and spirometry. We adjusted for key respiratory confounders. No subject had radiological features of silicosis. The high relative to low exposure group had significantly elevated adjusted odds ratios (aORs) for upper respiratory symptoms (aOR: 2.76, 95% CI: 1.28–5.97), chest wheezing (aOR: 3.78; 95% CI: 1.60–8.96), and spirometry-diagnosed chronic obstructive pulmonary disease (COPD) (aOR: 8.17; 95%CI: 1.01–65.85). These findings were similar for the high relative to medium exposure group, but no significant associations were found for the medium versus low exposure group. Chronic bronchitis and tuberculosis risks did not differ significantly among groups. CEI and exposure group produced similar results. In conclusion, residents residing <500 m from mine dumps had elevated adverse respiratory health effects

Environmental silica dust exposure and pulmonary tuberculosis in Johannesburg, South Africa

Abstract: Background: Occupational crystalline silica dust exposure is associated with an elevated risk of pulmonary tuberculosis (PTB). However, there is less evidence for an association with environmental silica dust exposure. Methods: A cross-sectional study of 310 participants was conducted in an exposed community living within 2 km of gold mine tailings and an unexposed population residing more than 10 km from the nearest gold mine tailing. Chest radiographs (n = 178) were read for PTB, past or current, by three readers. Results: Past or current PTB was radiologically identified in 14.4% (95%CI 9.2–21.8) in the exposed and 7.5% (95%CI 2.8–18.7) in the unexposed groups. Multivariate logistic regression models suggested that PTB prevalence was independently associated with exposure to second-hand smoke (OR = 8.13, 95%CI 1.16–57.22), a lower body mass index (OR = 0.88, 95%CI 0.80–0.98), previous diagnosis and treatment of PTB (OR = 8.98, 95%CI 1.98–40.34), and exposure to dust in the workplace from sand, construction, and/or mining industries (OR = 10.2, 95%CI 2.10–50.11). Conclusion: We found no association between PTB and environmental exposure to gold mine tailing dust. However, workplace silica dust exposure is a significant risk factor for PTB in South Africa, and PTB patients of working age should be screened for silica exposure

Rates of SAB at five hospitals in Gauteng and Western Cape during 2014.

<p>Rates of SAB at five hospitals in Gauteng and Western Cape during 2014.</p

The number of SAB cases at five hospitals in Gauteng and Western Cape during 2014.

<p>AST, antimicrobial susceptibility testing results; SAB, <i>S</i>. <i>aureus</i> bacteraemia; CA, community-associated; HA, hospital-associated; MSSA, methicillin sensitive <i>S</i>. <i>aureus</i>; MRSA, methicillin-resistant <i>S</i>. <i>aureus</i>.</p

Multivariable analysis of risk factors for HA-MRSA infection in comparison to HA-MSSA infection among hospitalised patients in Gauteng and Western Cape during 2014.

<p>Multivariable analysis of risk factors for HA-MRSA infection in comparison to HA-MSSA infection among hospitalised patients in Gauteng and Western Cape during 2014.</p

Univariate analysis of risk factors for HA-MRSA infection in comparison to HA-MSSA infection among hospitalised patients in Gauteng and Western Cape during 2014.

<p>Univariate analysis of risk factors for HA-MRSA infection in comparison to HA-MSSA infection among hospitalised patients in Gauteng and Western Cape during 2014.</p

The Epidemiology of Meningitis among Adults in a South African Province with a High HIV Prevalence, 2009-2012.

INTRODUCTION:Meningitis is a major cause of mortality in southern Africa. We aimed to describe the aetiologies and frequencies of laboratory-confirmed fungal and bacterial meningitis among adults in a South African province with an 11% HIV prevalence, over 4 years. METHODS:We conducted a retrospective, observational study of secondary laboratory data, extracted on all cerebrospinal fluid (CSF) specimens submitted to public-sector laboratories in Gauteng province from 2009 through 2012. We calculated cause-specific incidence rates in the general and HIV-infected populations and used Poisson regression to determine if trends were significant. RESULTS:We identified 11,891 (10.7%) incident cases of meningitis from 110,885 CSF specimens. Cryptococcal meningitis, tuberculous meningitis and pneumococcal meningitis accounted for 62.3% (n = 7,406), 24.6% (n = 2,928) and 10.1% (n = 1,197) of cases over the four-year period. The overall incidence (cases per 100,000 persons) of cryptococcal meningitis declined by 23% from 24.4 in 2009 to 18.7 in 2012 (p <0.001) and decreased by 19% among HIV-infected persons from 178.2 to 144.7 (p <0.001). Tuberculous meningitis decreased by 40% from 11.3 in 2009 to 6.8 in 2012 (p <0.001) and decreased by 36% among HIV-infected persons from 54.4 to 34.9 (p <0.001). Pneumococcal meningitis decreased by 41% from 4.2 in 2009 to 2.5 in 2012 (p <0.001) and decreased by 38% among HIV-infected persons from 28.0 to 17.5 (p <0.001). Among cases of other bacterial meningitis (248/11,891, 2.1%), Neisseria meningitidis (n = 93), Escherichia coli (n = 72) and Haemophilus influenzae (n = 20) were the most common organisms identified. CONCLUSIONS:In this high HIV-prevalence province, cryptococcal meningitis was the leading cause of laboratory-confirmed meningitis among adults. Over a 4-year period, there was a significant decrease in incidence of cryptococcal, tuberculous and pneumococcal meningitis. This coincided with expansion of the national antiretroviral treatment programme, enhanced tuberculosis control programme and routine childhood immunisation with pneumococcal conjugate vaccines

Large Outbreaks of Fungal and Bacterial Bloodstream Infections in a Neonatal Unit, South Africa, 2012–2016

Candidemia is a major cause of healthcare-associated infections. We describe a large outbreak of Candida krusei bloodstream infections among infants in Gauteng Province, South Africa, during a 4-month period; a series of candidemia and bacteremia outbreaks in the neonatal unit followed. We detected cases by using enhanced laboratory surveillance and audited hospital wards by environmental sampling and epidemiologic studies. During July–October 2014, among 589 patients, 48 unique cases of C. krusei candidemia occurred (8.2% incidence). Risk factors for candidemia on multivariable analyses were necrotizing enterocolitis, birthweight <1,500 g, receipt of parenteral nutrition, and receipt of blood transfusion. Despite initial interventions, outbreaks of bloodstream infection caused by C. krusei, rarer fungal species, and bacterial pathogens continued in the neonatal unit through July 29, 2016. Multiple factors contributed to these outbreaks; the most functional response is to fortify infection prevention and control