Occupational lung diseases in South African miners at autopsy: 2020 surveillance report

The Pathology Division at the National Institute for Occupational Health (NIOH) provides autopsy services for deceased workers who worked in controlled mines or works under the provisions of the South African Occupational Diseases in Mines and Works Act, 1973 (Act No. 78 of 1973). This report describes the ages, commodities, employment durations, and occupational cardio-respiratory diseases in miners whose organs were submitted for autopsies in 2019 and 2020. Data were exported from the PATHAUT database into STATA for analysis. Differences in the proportions of disease (expressed per 1 000) were calculated using the Pearson's chi-square test; significance was set at p ≤ 0.05. There were 759 and 557 records of deceased miners and ex-miners in 2019 and 2020, respectively. Pulmonary tuberculosis decreased from 192/1 000 in 2019 to 153/1 000 autopsies in 2020, and silicosis decreased from 246/1 000 to 223/1 000. However, neither decrease was significant. There was a significant increase in the rate of asbestosis from 50/1 000 in 2019 to 79/1 000 in 2020. Pulmonary tuberculosis (TB), emphysema, and silicosis were the most frequent diseases, with high rates. There was a non-significant decrease in occupational respiratory disease rates in 2020 from 2019, but these remain higher than the rates seen in the early 1990s. The NIOH continues to conduct autopsy surveillance on miners to support compensation for families, and the development of policy and intervention programmes in the mining industry

Noise-induced hearing loss and hearing conservation in the iron and steel industry in South Africa

Background and Purpose: The iron and steel industry in South Africa has been identifi ed as one of the highest risk industries in terms of noise induced hearing loss (NIHL). The National Institute for Occupational Health was commissioned by the Department of Labour to audit the current noise exposure levels and hearing conservation practices in eight major producers of iron and steel; and to make recommendations regarding prevention strategies. Methods: The audit was conducted in two parts: the noise exposure levels and hearing conservation practices were assessed by the occupational hygiene department. The occupational medicine department assessed the hearing conservation policies and procedures; reviewed employees' medical records to ascertain the number of NIHL cases; and conducted verifi cation of audiograms on a sample of employees working in noise zones. Results: Area noise levels exceeding 105 dB(A) were measured in four of the eight workplaces. The estimated average annual incidence of NIHL varied from 0.7 - 8.3/1000/year. All companies did baseline; periodic and exit audiometric testing; but there were notable discrepancies between companies and verifi cation audiograms and differences of more than 20 dB(A) were found. Although information and training on noise was reportedly done in all worksites; a high proportion of workers could not demonstrate correct fi tting of hearing protection devices or recall when last they were trained. Conclusion: A detailed standard operating procedure should be implemented for medical surveillance for NIHL with action timelines that initiate remedial processes prior to employee developing compensable disease. Aggregated audiometric testing results should be communicated to managers and health and safety teams to provide guidance to prioritise areas for control measures. A quality assurance programme for audiometric testing must be implemented. An evaluation tool to measure the effectiveness of the noise and hearing conservation training provided to employees; including contracted employees; should be adopted

Seroprevalence of anti-Toxoplasma gondii antibodies in HIV/AIDS patients and healthy blood donors at the Port Moresby General Hospital, Papua New Guinea

The findings of a seroepidemiological study into the prevalence of Toxoplasma gondii infection amongst normal blood donors and patients infected with HIV (human immunodeficiency virus) are presented. Of the total 301 participants, 181 were HIV antibody positive and 120 blood donors were HIV antibody negative. We used a prevalidated questionnaire, enzyme-linked immunosorbent assay (ELISA) and the Epi Info version 3.2 software plus SPSS version 10 for data analysis. The results showed an overall antibody prevalence rate of 53% in the population and a significantly higher infection rate amongst HIV-positive patients: odds ratio 2.14 (95% CI 1.30-3.53), p = 0.001. The study further showed that exposure to cats and highlands origin were independent risk factors. This study has demonstrated that in light of the current HIV/AIDS (acquired immune deficiency syndrome) epidemic, opportunistic infections such as toxoplasmosis will be a cause of considerable morbidity and mortality. It is therefore important that clinicians and public health practitioners fit these findings into overall management strategies to help control toxoplasmosis.