Killing of fabric-associated bacteria in hospital laundry by low-temperature washing

J Infect Dis. 1984 Jan;149(1):48-57. doi: 10.1093/infdis/149.1.48.

Abstract

Hospitals using 71.1 C water for laundering consume vast amounts of energy. We studied whether washing at 22 C would result in fabric-associated bacterial counts significantly different from those remaining after the high-temperature wash procedure in general use. Using a standard method to enumerate fabric-associated bacteria, we found that soiled sheets and terry cloth items were contaminated, respectively, with 10(6) and 10(8) cfu/100 cm2 of fabric area, predominantly gram-negative rods (especially Enterobacteriaceae and Pseudomonadaceae). Staphylococcus species were the most common gram-positive organisms. A standard low-temperature washing cycle without laundry chemicals removed 3 log10 of bacteria by agitation, dilution, and drainage. When low-temperature laundry chemicals were used, 3 log10 of bacteria were killed after the bleach was added, and sheets and terry cloth items had postwash colony counts of 10(1)-10(2) cfu/100 cm2. Drying removed an additional 1-2 log10 organisms. Bacterial counts and species from low- and high-temperature washed fabrics were comparable. Low-temperature washing is therefore as effective as high-temperature washing for eliminating pathogenic bacteria from hospital laundry.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Bacteria / growth & development*
  • Bedding and Linens*
  • Enterobacteriaceae / growth & development
  • Fungi / growth & development*
  • Laundering
  • Laundry Service, Hospital*
  • Pseudomonas / growth & development
  • Staphylococcus / growth & development
  • Temperature