Allergenicity of latex rubber products used in South African dental schools

Background: Allergens from latex products in healthcare settings have been known to trigger latex induced allergic reactions in healthcare workers (HCWs). There is a need to quantify individual latex allergens in products in order to assess the allergenicity of latex products used in health care settings, so as to minimize the risk of sensitisation to these proteins. Methods: Fourteen latex examination gloves representing six brands (powdered and non-powdered) and five dental rubber dams from five dental academic institutions were analysed for latex allergens and total protein. Total protein content was determined using the BIORAD DC protein assay kit and natural rubber allergen levels using a capture ELISA assay specific for hev b 1, hev b 3, hev b 5 and hev b 6.02. Results: Hev b 6.02 was found in higher concentrations than other NRL allergens in the products analysed. Hev b 5 content ranged from 0 to 9.2µg/g and hev b 6.02 from 0.09 to 61.5µg/g of sample. Hev b 1 levels were below the detection limit (DL) for 79% of the samples (15/19). Dental dams showed higher allergen levels (median: 80.91µg/g) in comparison to latex gloves (median: 11.34µg/g). Powdered rubber samples also showed higher allergen levels (median: 40.54µg/g) compared to non-powdered samples (median: 5.31µg/g). A statistically significant correlation was observed between total protein and total allergen (r=0.74, p<0.001) concentrations. Conclusion Natural rubber latex (NRL) allergen concentrations differ significantly by product and brand. This study has demonstrated that NRL allergens in latex containing products used in South African dental institutions are present at sufficiently high levels to pose an allergic health risk

Pilot study to detect airborne Mycobacterium tuberculosis exposure in a South African public healthcare facility outpatient clinic

BACKGROUND : Airborne transmission of Mycobacterium tuberculosis (TB) remains an occupational health hazard particularly in crowded and resource limited healthcare settings. AIM : The study aimed to quantify airborne TB in a busy outpatient clinic in Gauteng, South Africa. METHODS : Personal (HCWs) and stationary air samples were collected in the Polyclinic and Administrative block. Quantitative real-time PCR was used to detect airborne TB. Walkthrough observations and work practices of HCWs were also recorded. FINDINGS : TB was detected in 11/49 (22.4%) of the 9/25 (36%) personal and 2/24 (8.3%) stationary samples. Samples from 5 of 10 doctors (50%) and 3 of 13 nurses (23%) were positive. Repeat measurements on different days showed variable results. Most of the HCWs (87.5%) with positive results had been in contact with coughing patients and had not worr respiratory masks despite been training. CONCLUSION : The use of air sampling coupled with real-time qPCR is a simple and effective tool to demonstrate the risk of TB exposure. The findings provide an impetus for hospital management to strengthen TB infection prevention and control measures.Canadian Institutes of Health Research (CIHR).http://www.elsevierhealth.com/journals/jhinhb2016School of Health Systems and Public Health (SHSPH

Relationship between Pesticide Metabolites, Cytokine Patterns, and Asthma-Related Outcomes in Rural Women Workers

The objective of this study was to investigate the relationship between exposure to organophosphate (OP) and pyrethroid (PYR) pesticides with serum cytokine patterns and asthma-related outcomes among rural women workers. A cross-sectional study was conducted among rural women (n = 211), including those working and living on farms and nearby town dwellers. Pesticide exposure was assessed using urinary metabolite concentrations of OP and PYR pesticides. Health outcome assessment was ascertained through the European Community Respiratory Health Survey (ECRHS) questionnaire, fractional exhaled nitric oxide (FeNO), and serum cytokines associated with asthma. The prevalence of doctor-diagnosed asthma was 11%, adult-onset asthma 9%, and current asthma 6%. In this population, the proportion of T helper type 2 (Th2) cytokines (interleukin (IL)-4, IL-5, and IL-13) detectable in subjects was between 18% and 40%, while the proportion of non-Th2 cytokines (IL-6, IL-8, IL-10, IL-17, and interferon gamma) was between 35% and 71%. Most Th2 and non-Th2 cytokines were positively associated with either OP or PYR metabolites. Non-Th2 cytokines showed much stronger associations with OP metabolites (Dimethyl phosphate OR = 4.23; 95% CI: 1.54–11.65) than Th2 cytokines (Dimethyl phosphate OR = 1.69; 95% CI: 0.83–3.46). This study suggests that exposure to most OP and some PYR pesticides may be associated with asthma-related cytokines, with non-Th2 cytokines demonstrating consistently stronger relationships

Occupational Risk of Airborne Mycobacterium tuberculosis Exposure: A Situational Analysis in a Three-Tier Public Healthcare System in South Africa

This study aimed to detect airborne Mycobacterium tuberculosis (MTB) at nine public health facilities in three provinces of South Africa and determine possible risk factors that may contribute to airborne transmission. Personal samples (n = 264) and stationary samples (n = 327) were collected from perceived high-risk areas in district, primary health clinics (PHCs) and TB facilities. Quantitative real-time (RT) polymerase chain reaction (PCR) was used for TB analysis. Walkabout observations and work practices through the infection prevention and control (IPC) questionnaire were documented. Statistical analysis was carried out using Stata version 15.2 software. Airborne MTB was detected in 2.2% of samples (13/572), and 97.8% were negative. District hospitals and Western Cape province had the most TB-positive samples and identified risk areas included medical wards, casualty, and TB wards. MTB-positive samples were not detected in PHCs and during the summer season. All facilities reported training healthcare workers (HCWs) on TB IPC. The risk factors for airborne MTB included province, type of facility, area or section, season, lack of UVGI, and ineffective ventilation. Environmental monitoring, PCR, IPC questionnaire, and walkabout observations can estimate the risk of TB transmission in various settings. These findings can be used to inform management and staff to improve the TB IPC programmes