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

BACKGROUND

Airborne transmission of Mycobacterium tuberculosis remains an occupational health hazard, particularly in crowded and resource-limited healthcare settings.

AIM

To quantify airborne M. tuberculosis in a busy outpatient clinic in Gauteng, South Africa.

METHODS

Stationary air samples and samples from healthcare workers (HCWs) were collected in the polyclinic and administrative block. Quantitative real-time polymerase chain reaction (PCR) was used to detect airborne M. tuberculosis. Walkthrough observations and work practices of HCWs were also recorded.

FINDINGS

In total, M. tuberculosis was detected in 11 of 49 (22.4%) samples: nine of 25 (36%) HCW samples and two of 24 (8.3%) stationary air samples. Samples from five of 10 medical officers (50%) and three 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 worn respiratory masks despite training.

CONCLUSION

The use of air sampling coupled with quantitative real-time PCR is a simple and effective tool to demonstrate the risk of M. tuberculosis exposure. The findings provide an impetus for hospital management to strengthen infection prevention and control measures for tuberculosis.

Occupational exposure to endotoxin from contaminated dental unit waterlines

INTRODUCTION

Fine aerosolised droplets and splatter generated during dental procedures influences the composition of the indoor air quality of dental care facilities and poses a potential threat to the workers' health. Therefore there is a need to assess the risks from exposure to bioaerosols and splatter and identify measures of reducing possible hazards.

METHODOLOGY

A review of the literature related to occupational exposure and health hazards in dentistry was conducted. The search primarily focused on endotoxin exposure from contaminated dental unit waterlines.

RESULTS

This review highlights the various occupational hazards experienced by dental personnel. However, focus is directed on exposure to biological agents as a result of fine aerosol and splatter generated from dental procedures. More emphasis is on endotoxin exposure from contaminated dental unit waterlines and the negative impact it may have on dental workers. The review also aims to inform the reader of proposed endotoxin levels in both air and water and how and by whom it should be measured.

CONCLUSION

Understanding the main sources of endotoxin in dental practice and its influence on indoor air and potential threat to dental workers is pertinent to infection control strategies.

Genetic polymorphisms at three loci in two populations of Manipur, India

The Phayengs and Khurkhuls are sections of the Meiteis, the largest community in Manipur, India. Racially they are Mongoloids, and marry mostly among themselves. The present study reveals the frequencies of ABO blood groups as A1 (36.54%), B (28.85%), O (25.96%) and A1B (8.65%) in the Phayengs (n = 124) and A1 (39.84%), B (21.14%), O (22.76%) and A1B (16.26 %) in the Khurkhuls (n = 123). The subtype A2 is completely absent in both. The gene frequencies are ABO*A1 = 0.262, ABO*B = 0.212 and ABO*O = 0.526 for the Phayeng and ABO*A1 = 0.334, ABO*B = 0.206, ABO*O = 0.526 among the Khurkhuls. The Phayengs show a frequency of Rh negatives as 1.92%, the frequency of the RH*d allele being 0.139. The incidence of HB E is 38.46% resulting into the frequency of HB*E = 0.266. This is the highest value so far reported from Manipur State. No Rh(D) negative individuals have been encountered among the Khurkhuls, and the incidence of HB E is 16.26%, the frequency of HB*E being 0.085.

A case of paragonimiasis in a civet cat with a new Paragonimus sub species in Manipur, India

A case of paragonimiasis in a civet cat with a new Paragonimus sub species in Manipur, India.

Stature and footsize in four Thai communities of Assam, India

An attempt has been made to examine correlationships between stature and footlength, stature and footbreadth, and footlength and breadth among four Thai (male) populations of Assam (India), viz. the Khamyangs, the Turungs, the Aitons and the Khamitis. Significant positive correlations have been found in all the cases. Mean values of the indices have revealed a more or less constant ratio of stature and footsize at all heights suggesting the possibility of estimating stature from footlength or breadth and vice versa. Estimation of stature from footlength is, however, preferable to estimation from footbreadth. The Turungs stand for the tallest in stature and biggest foot measurements. They fall into 'medium' stature of the Martin's scale while the others fall into 'below medium'. Statistically significant difference has been observed the Turungs and the Khamyangs in respect of footbreadth, between the Turungs and the Aitons in footlength and, between the Khamyangs and the Khamtis in respect of stature footbreadth index.

paragonimiasis in Manipur

A survey was undertaken in the east district of Imphal valley of Manipur, India, using an intradermal test with saline extract of adult Paragonimus westermani as test antigen to find out the prevalence of paragonimiasis and some of the epidemiological factors attributable to it. A total of 3,467 individuals of both sexes aged five years and above were tested. A total of 2934 persons admitted eating crabs and among them 234 were found reactive to Paragonimus antigen. The prevalence rate observed was 6.7 per cent. The proportion of positive reactors (8.0%) among the crab eaters compared to 0.1 per cent among those who did not eat crabs was highly significant (P < 0.01). The difference in the prevalence rates in different age groups and different sexes was also found to be highly significant. The habit of eating raw and or undercooked crabs had significant correlation with skin reactivity. The intradermal test was found to be a good screening test for mass surveys due to its simplicity, low cost, high sensitivity and no known untoward reaction. Four persons among the skin positive reactors presented with cough, pain in the chest, recurrent haemoptysis as major clinical manifestations. Laboratory investigations revealed Paragonimus eggs in the sputum smears, raised erythrocyte sedimentation rate, and high absolute eosinophil count in their blood. Praziquantel, the drug of choice was given at a dose of 25 mg per kg body weight 3 times a day for three consecutive days to each patient for a cure.

A note on the frequency distribution of AB0 and rhesus blood groups in four Thai populations of Assam (India) and their position among the Mongoloids of this region

An attempt has been made to give a picture of the distribution of AB0 and Rhesus blood groups in four Thai populations of Assam, India. Intragroup heterogeneity and their position among the Mongoloid populations of this region have also been examined. In all of these groups the frequency of the 0-allele was found to be the most predominant one followed by B- and A-alleles, respectively. A similar trend is observed in some other populations of Asia. The populations under study show statistically similarity with none of the Mongoloid populations of Assam. The incidence of Rhesus-negatives in the populations under study ranges from complete absence to below 2%.

Pulmonary paragonimiasis: clinical features, diagnosis and treatment of 39 cases in Manipur

Thirty-nine cases of pulmonary paragonimiasis due to Paragonimus westermani were identified in Manipur, India. Recurrent haemoptysis, often increased on exertion, was the most common symptom. The clinical features and radiological appearances simulated pulmonary tuberculosis and 23 cases were treated for tuberculosis for varying periods before the final diagnosis. Young males aged 11 to 30 years comprised two-thirds of the cases. The disease was acquired by eating raw or improperly cooked crabs (Potamon deham). Intradermal tests (IDT) employing a saline extract of adult Paragonimus were a simple and reliable method of detecting present or past infection. Erythema of large size even without wheal and pseudopodia may indicate a positive IDT. Charcot-Leyden crystals (CLC) were detected in all sputum samples positive for Paragonimus ova. In patients (four) presenting with pleural effusion, Paragonimus ova were not present in the sputum, stool or pleural fluid. Bithionol (2,2'-thiobis [4,6-dichlorophenol]) orally, 40 mg/kg body-weight/day, 10 to 25 doses, cured all cases and, except in one, side effects were minimal. Relapse in one patient after six months' treatment was apparently cured by a second course of Bithionol.