Wind-driven roof turbines' effectiveness in enhancing household ventilation: a potential tool to reduce tuberculosis infection

Background: South Africa's overburdened healthcare systems have led to criticism of its unsustainable tuberculosis management interventions. In 2011, the National Department of Health implemented an outpatient, decentralised care model, but this increased costs and jeopardised the long-term viability of prevention measures. Home confinement is now recognised as a viable intervention option, when combined with safety precautions such as ventilation and medical support. However, little is known about the risk of infection in this context. Objectives: To assess the effectiveness of wind-driven roof turbines in enhancing ventilation and their potential to lower the risk of Mycobacterium tuberculosis infection in a residential setting. Methods: Eight houses were selected and divided equally into intervention (wind turbines installed) and control groups, using a pairwise comparison method. The CO2 decay method was used as a proxy to determine ventilation in the houses. The wind-driven roof turbines' potential to lower the risk of Mycobacterium tuberculosis infection was stochastically evaluated using the Wells-Riley mathematical model. Results: During two seasons, installation of a roof turbine resulted in twofold ventilation rates compared to the control houses. Consequently, the WellsRiley model predicted a twofold reduction in the probability of infection in the intervention compared to the control households. Conclusion: Low-cost, low-maintenance wind-driven roof turbines are effective in increasing ventilation in houses, and should be considered as an additional layer of protection against Mycobacterium tuberculosis and other infections in residential settings.

Evaluating awareness of health risks and self-reported symptoms among nail technicians in Johannesburg, South Africa ­ a pilot study

Background: The professional nailcare industry is expanding rapidly in South Africa. Nail treatment involves the use of solvents and acrylates. Exposure to these chemicals is associated with skin, eye, and respiratory tract irritation, and neurological and reproductive health effects. Objective: To test the feasibility of conducting a study on formal and informal nail technicians, which included testing a self-developed questionnaire, and to collect preliminary data about their knowledge and awareness of health risks associated with exposure to chemicals in nail products, and associated symptoms. Methods: A self-developed questionnaire was administered to 10 formal and 10 informal nail technicians working in conveniently selected nail salons in Johannesburg. Work practices and exposure control measures were observed. Demographic characteristics, working conditions, awareness of health risks, and self-reported symptoms in the two groups are presented as frequency distributions. Results: Poor phrasing was identified in some of the questions. Participants provided the correct terminology to describe nail services. The revised questionnaire comprised 39 questions. Seven of the informal nail technicians were male while all the formal nail technicians were female. Informal nail technicians worked longer hours per week than formal nail technicians (median of 61.5 and 46.5 hours, respectively) and reported more symptoms. Informal nail technicians used a wider range of nail products than formal nail technicians and used some unknown brands. Although all participants indicated that they were aware of health risks associated with nail products, only four of the formal nail technicians and one informal nail technician reported receiving training (although not specific to health and safety). Informal nail technicians reported using personal protective equipment (PPE); however, this practice was inconsistent, and they used the incorrect PPE. Conclusions: We showed that conducting a larger study in nail technicians is feasible. The questionnaire was revised to include more information about the chemical content of nail products, a wider range of symptoms, the frequency of their occurrence, and the work-relatedness nature of the self-reported symptoms. A knowledge gap was identified among nail technicians relating to risks associated with exposure to chemicals in nail products. The questionnaire was refined to assess more accurately nail technicians' understanding of exposure and awareness of health risks associated with chemicals in nail products.

Curaçao patients with coronary artery disease have a higher prevalence of the HFE C282Y mutation

Epidemiological studies indicate a positive relation between iron status and coronary artery disease (CAD) risk The HFE C282Y allele is associated with increased iron status and higher CAD risk. We investigated whether HFE C282Ymight be a CAD risk factor in Curaçao in a case-control study design. The patient group comprised 42 men and 10 women. Fifty-four men and 30 women without history of CAD served as age and gender matched controls. HFE C282Y genotypes were established using sequence-specific priming polymerase chain reaction. None of the investigated subjects were homozygous for HFE C282Y, whereas 5/52 (9.6) CAD patients and 1/84 controls (1.2) were heterozygous for HFE C282Y (p = 0.03). The HFE C282Y mutation was 8.8 fold (95 CI 1.001, 77.8; p = 0.049) more prevalent in CAD patients than in controls. The HFE C282Y allele frequency in Curaçao is higher than that of African populations, but comparable with that of Jamaica. We conclude that Curaçao CAD patients have somewhat higher frequency of HFE C282Y heterozygosity than controls, and that the HFE C282Y allele frequency in the Curaçao population is higher than might be expected in persons of African descent. The consequences of HFE C282Y heterozygosity as CAD risk factor are as yet uncertain, since there is no proof that iron lowering reduces CAD risk

Lipids, apoliprotein-E genotypes and other risk factors of patients with coronary artery disease in Curacao

We studied lipids, apolipoprotein-E (apo-E) genotypes and other coronary artery disease (CAD) risk factors of 67 CAD patients (male/female ratio 5) in Curacao. Compared with 57 controls, male CAD patients had higher cholesterol, triglycerides, LDL-cholesterol, apo-B and decreased HDL-cholesterol and HDL-cholesterol/cholesterol concentrations. Other CAD risk factors were: increased fasting glucose and Hba concentration, decreased creatinine clearance, and increased prevalences of lipoprotein (a) concentration > 500 mg/l, renal disease, hyperhomcysteinaemia, diabetes mellitus type II (DM-II), positive CAD family history and cigarette smoking. Male CAD patients had higher plasma Ó-tocopherol. Compared with 29 female controls, female CAD patients had higher fasting plasma glucose with HbA concentrations, and prevalence of DM-II. Predicting factors for CAD development in the whole CAD group were: DM-II, cigarette smoking, apo-E/E and apo-E/E Apo-E was associated with lower HDL-and higher LDL-cholesterol concentrations. There is a need for local studies on improvement of diabetic control, reference values of lipoprotein (a) and homocysteine concentrations, on apolipoprotein (a) phenotypes, causes of hyperhomocysteinaemia, and dietary influences on CAD development in subject who carry the apo-E allele.

The dietary fatty acids of patients with coronary artery disease and control in Curacao: implications for primary and secondary prevention

Patients with coronary artery diseases are advised to augment their dietary linoleic acid intakes at the expense of saturated fatty acids. We investigated whether the dietary linoleic acid intake of 57 patients with coronary artery disease (47 males, 10 females; ages 61 ñ 10 years) in Curacao is higher as compared with 77 controls (51 males, 26 females; ages 56 ñ 7 years). For this, we measured plasma cholesterol ester fatty acids, which reflect the dietary fatty acid composition of the preceeding weeks. Patients with coronary artery disease and controls had minor differences in cholesterol ester fatty acids. Their cholesterol ester linoleic acid content suggests that the dietary polyunsaturated/saturated fatty acid ratio is far below 1. Comparison with data reported for the the Netherlands, Greenland and Crete showed that the dietary fatty acid composition in Curacao is typically Western with a high intake of saturated fatty acids, a low intake of monounsaturated fatty acids and the consumption of linoleic acid as the predominant polyunsaturated fatty acid. Intake of long chain polyunsaturated fatty acids from fatty fish is low. Reduction of dietary saturated fatty acids, augmentation of fish consumption, and an increase of the Ó-linolenic/linoleic acid ratio are likely to be of benefit to both primary and secondary prevention from coronary artery disease in Curaco.