Now my basic degree is in environmental health – and that has a strong focus on hygiene. But despite this, every time my mother comes to visit, she replaces my broom and throws out my dishcloths. Weird…yes I know, we Stoneham’s have some strange habits. Does it annoy me? Yes. My theory is that mothers were put on this earth to not only nurture their kids but to regularly annoy them. So it intrigued me to find an entire journal article on dishcloths.
This month’s JournalWatch feature article investigates the hygiene around dishcloths…who would have thought? In a nutshell, the study assessed the possibility that dishcloths used in households could contribute to the occurrence of diarrhoea. The authors found that the presence of both total coliforms and E. coli in the dishcloth samples taken, can indicate the presence of other pathogens further increasing the risk for diarrhoea and other related infections.
Dishcloths as the name suggests are used for washing dishes. However many people use them to clean spills and in many African homes, where this study was conducted, dishcloths are used for multiple purposes such as cleaning dishes, wiping various surfaces, walls and floors.
You can imagine, then, that those dishcloths are picking up a lot more than they’re meant to, including bacteria. One researcher has claimed that there are around 10 million bacteria per square inch of a kitchen sponge and a million per square inch on a dishcloth.
The study, led by Vidya Keshav from the Water and Health Research Centre, Faculty of Health Sciences at the University of Johannesburg collected 424 dishcloths from households in five suburbs of Johannesburg. The central aim was to see if the dishcloths were facilitating the survival of microorganisms in domestic kitchens which would then support cross contamination to other areas. Kitchen dishcloths and sponges have been reported to have the highest bacterial count as they mostly remain wet and serve both as a reservoir and disseminator of pathogens.
The researchers were looking for E. coli as this is an indicator organism. An indicator organism provides evidence of the presence or absence of a pathogenic organism surviving under similar physical, chemical, and nutrient conditions. Because many pathogens are not easily detected, indicator organisms are a fundamental monitoring tool used to measure both changes in environmental quality or conditions and the potential presence of hard-to-detect target pathogenic organisms. So in essence, E. coli was chosen to evaluate the hygienic status of dishcloths and sponges.
The households were asked to place the dishcloths in sterile bags in exchange for new dishcloths. Before the dishcloths were analysed, a brief description on the quality of dishcloths was noted including whether they were dirty or clean, wet or dry, as well as the actual measurements.
A complex microbial analysis to detect the presence of coliforms and E. coli was undertaken on a 5cm2 piece of each sponge. The results showed that of the 424 samples collected 37% were identified as drying cloths, 63% as wash cloths and 0.7% as sponges. The sanitary status of the cloths was recorded as 56% dirty cloths and 44% clean cloths based on visual observations.
The analysed cloths detected total coliforms in 98 of the samples and in addition, 42% of the cloths analysed tested positive for the presence of E. coli. So this basically means that the kitchen sponge is probably one of the dirtiest things in your house!
To counter this accumulation of bacteria, the researchers suggested a need for public education regarding hygiene in the households, especially if the same dishcloth is used for various tasks. Simply washing the dishtowels in the sink with some detergent is not enough, because bacteria like E. coli are resilient and can repopulate within 24 hours.
The proposed education may cover encouraging the users to soak the cloths in bleach for two minutes or microwaving it for 15 minutes. Although this won’t guarantee cleanliness, homeowners can take further steps to ensure cleanliness, such as washing hands thoroughly…or changing dishcloths often….which I think was what my mother was encouraging me to do! So maybe mothers do know best!
E.Coli from dishcloths as an indicator of hygienic status in households by V. Keshav, C. A. Kruger, A. Mathee, N. Naicker, A. Swart and T. G. Barnard. Journal of Water, Sanitation and Hygiene for Development; 5 (3).
The Public Health Advocacy Institute WA (PHAIWA) JournalWatch service reviews 10 key public health journals on a monthly basis, providing a précis of articles that highlight key public health and advocacy related findings, with an emphasis on findings that can be readily translated into policy or practice.
These reviews are then emailed to all JournalWatch subscribers and are placed on the PHAIWA website. To subscribe click to Journal Watch click here