摘要：The author examined the sewage from 5 towns with tuberculosis sanatoria and from one institution for the care of the feeble-minded, which had a tuberculosis ward, for the presence of tubercle bacilli. The 6 effluents were treated in biological-purification plants and average samples taken. These were centrifuged, and the sediment treated for 1 hour at 37°C with 4% NaOH before inoculation into guinea-pigs. Tubercle bacilli were demonstrated in the influent to all the plants and in the digested sludge of all those operating on sewage where the ratio of infective patients to all persons connected with the plant was up to 1:600. Experiments with cultivated tubercle bacilli showed that centrifuging of sewage resulted in only an insignificant loss of bacilli, but that NaOH treatment caused a loss of over 99%. After consideration of the risk of infection to both man and cattle from the sewage of tuberculosis institutions, the author reports on his own studies on the killing of tubercle bacilli in sewage. It took about 11½-15 months before tubercle bacilli could no longer be demonstrated in sludge that had been kept on the drying beds. The addition of 10 mg of chlorine per litre of biologically purified effluent from an activated-sludge plant was found effectively to destroy tubercle bacilli. Disinfection of sludge was also carried out with 0.5% lysol and 0.1%-0.2% formol; 3.1% copper sulfate proved ineffective. The author concludes that the disinfection of sewage from tuberculosis institutions presents no special difficulties, but that work on this subject in different countries should be co-ordinated in an effort to improve plant and reduce costs. Full text Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (949K), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References . 171 172 173 174 175 176 177 178 179
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