Dust control in measles wards, with a note on sulphadiazine prophylaxis

Determination of bacterial air pollution in various premises

A simple method, applicable in routine work, for simultaneous air sampling of total bacteria, on serum agar, and Str. salivarius and Bact. coli on specific media, is described.

Simultaneous air sampling including, in addition to detection of total bacteria, Str. salivarius and Bact. coli as indicators of buccal and faecal air-borne bacteria, respectively, reveals the kind and source of air-borne pollution much better than the simple total bacterial count.

The air in various medical and public institutions was examined; the results are presented and discussed. The air pollution of the premises examined was relatively high, especially in the operating theatres. The air of infants' wards was found to be heavily polluted with Bact. coli as a result of poor nursing technique and this might have had bearing on the epidemic of infant diarrhoea.

Transmission of group A streptococci. III. The effect of drying on the infectivity of the organism for man

The sources of airborne bacteria within living quarters are minute droplet nuclei which remain suspended in the air following expulsion from a carrier and contaminated particles which have become suspended from dried environmental deposits. Since group A streptococci may be isolated from environmental deposits in populations experiencing an epidemic of streptococcal respiratory disease (Loosli, Lemon, Wise & Robertson, 1952), it has been assumed that contaminated particles of dust serve as an important reservoir of infection. Indeed, many of our measures employed to control respiratory infection in recent years have been directed against this reservoir.

Rapid diagnosis of Legionella pneumophila serogroup 1 infection with the Binax enzyme immunoassay urinary antigen test

The Binax legionella urinary antigen (LUA) enzyme immunoassay (Binax, Portland, Maine) was evaluated in 159 patients with suspected or proven legionellosis and 209 controls. A positive LUA test was found in 37% of patients with suspected legionellosis overall and in 83% of those with proven Legionella pneumophila serogroup 1 infection. The sensitivity of the LUA test was significantly greater than that of the direct fluorescent-antigen test (83 versus 42%; P < 0.0001) but not significantly different from that of culture (85%) or serology (91%); specificity was at least 99.5%.

Dioxin concentrations in the blood of workers at municipal waste incinerators

OBJECTIVES

Increased concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs) in pooled blood samples from workers at municipal waste incinerators have been reported. This study was undertaken to confirm these results in individual blood samples from potentially exposed and unexposed workers at municipal waste incinerators compared with matched unexposed controls and compared with concentrations in the slag and fly ash from the municipal waste incinerators.

METHODS

Concentrations of PCDDs and PCDFs were determined in the blood of 10 workers from an old municipal waste incinerator without adequate pollution controls, 11 workers from a newer incinerator with modern pollution controls, and 25 controls from the general population group matched for age (+/- 10 years), sex, and race, and in the slag and fly ash from the older incinerator.

RESULTS

Significant increases of certain PCDDs and PCDFs were found in the blood of the workers from the older incinerator compared with the controls as follows: octaCDD (1051 (438) v 637 (344), P < 0.001), hexaCDF (52.3 (28.7) v 30.2 (18.2), P < 0.01), heptaCDF (43.9 (30.4) v 22.7 (12.4), P < 0.001), total PCDDs (1262 (484) v 825 (454), P < 0.001), total PCDFs (133.0 (68.1) v 93.7 (36.7), P < 0.05), and total PCDD/Fs (1395 (537) v 918 (437), P < 0.001). The workers from the older incinerator with the greatest exposure were found to have the most significant increases of the blood PCDDs and PCDFs, and the pattern of increased PCDD and PCDF congeners in the blood corresponded to the pattern in the incinerator slag and ash. No significant differences were found between the blood concentrations of the workers at the newer incinerator and the controls.

CONCLUSION

Occupational exposure to slag and fly ash from municipal waste incinerators may increase the blood concentrations of PCDDs and PCDFs. Modern pollution control technology in new incinerators may be able to minimise potential exposure to slag and fly ash and thus the absorption of PCDDs and PCDFs from this source.

Evaluation of methods of applying oil to bedclothes and practical application of the selected method

Thomas & Van den Ende (1941) and Puck and his collaborators (Puck, Hamburger, Robertson & Hurst, 1945; Puck, Robertson, Wise, Loosli & Lemon, 1946) have shown that the application of small amounts of oil to bedclothes reduces the quantities of dust and bacteria liberated during bedmaking. Joyce Wright in her first investigation (Wright, Cruickshank & Gunn, 1944) found that oiling bedclothes was, consequently, effective in reducing the incidence of cross-infection, but this was not confirmed in her later work (Wright, Begg & Smellie, 1947), or by Krugman & Ward (1951). Barnard (1952), however, has recently shown that cross-infection can possibly arise by interchange of bacteria in blankets during laundering. Oiling of bedclothes may, therefore, be a very useful hygiene measure.