Microbial contamination of coffee during postharvest on farm processing: A concern for the respiratory health of production workers.

Coffee workers respiratory health problems, found to be associated with dust exposure in the coffee factories, but the content of the dust is not well known. A cross-sectional survey was conducted to assess the microbial contamination of coffee in dry and wet coffee process, from four farms in two regions of Ethiopia. A total of 36 samples of coffee were collected for laboratory investigation. The microbial load in the dry process ranged from 6.9 × 102 to 7.2 × 105 colony forming units (CFU)/mL while the microbial load in wet process ranged from 2.5 × 102 to 4.6 × 105 CFU/mL. The results indicate the presence of gram negative bacteria in dried and stored beans from both the wet and dry process. During further coffee processing possible release of endotoxin from coffee contaminated by gram negative bacteria might affect coffee workers respiratory health. Further studies are required to assess the relation between bacterial contamination of coffee and endotoxin level in coffee factories.

Misdiagnosis of pulmonary tuberculosis and associated factors in peripheral laboratories: a retrospective study, Addis Ababa, Ethiopia.

OBJECTIVE: Sputum smear microscopy reading errors are likely to result in failure to detect persons with infectious TB. This study was intended to review misdiagnosis of pulmonary TB and associated factors in peripheral laboratories. RESULTS: During the study period 1033 (10.5%) sputum smear positive and 8783 (89.5%) smear negative slides were reported by peripheral laboratories. The slides were re-read by the central referral laboratories (CRLs) as the reference standard reading. Of 1033 positive slides reported by peripheral laboratories, 25 (2.4%) were false positive. Out of 8783 smear negative slides reported by peripheral laboratories, 35 (0.4%) were false negative. The sensitivity, specificity, positive predictive value and negative predictive value of peripheral laboratories were 96.64, 99.72, 97.58, and 99.61% respectively. The peripheral laboratories and CRLs have an observed agreement (Po) of 0.9939. Of 135 peripheral laboratories, 93 (68.9%) read negative and positive slides correctly, 49 (36.3%) did not have lens cleaning tissue papers, 11 (8.1%) lacked frosted slides, and 14 (10.4%) had shortage of reagents. As conclusions, the peripheral laboratories and CRLs had high agreement for sputum smear microscopy reading. However, a few TB cases were misdiagnosed despite having the disease; these individuals might continue to spread the infection in the community.