How often should you clean pyjamas?
Discussing personal and household hygiene on BBC radio Derby with Andy Twigge.
Here are my notes and sources on the subject – make up your own mind:
- A complete layer of skin is lost and replaced on average every 4 days
- We release about a million skin particles a day
- Skin typically harbours up to 10 million bacteria per cm2
- Many thousands of bacterial species live on the skin, and a typical person will have about 150 different species on the hands alone
- Normal skin microbiota are beneficial and we should not seek to eliminate them
- Clothing typically harbours 100 – 1 million cells per cm2 – they are mostly non-pathogens and not a major problem to most people
- Clothing acts as a barrier to dispersal
- Washing clothes regularly is beneficial for lots of reasons not just microbial hygiene
- Immunocompromised people may be at higher risk
- Contaminated clothing is relatively low risk for behavioural reasons
- Hand hygiene is the most important
- Hand and food contact surfaces are next most important
- Kitchen cloths especially – are the biggest reservoir of active bacteria in the whole house, pathogens commonly reside there
- What is the route by which contaminated clothing could cause illness?
- Through contact with skin especially if broken
- Through doing the laundry – wash hands
- Wet clothing or hands significantly increases the chance of transfer
- Washing clothes is beneficial by:
- Diluting and washing off organisms
- Killing organisms which may stay attached
- Microbes are exchanged between items in the washing machine
- Higher temperatures and use of bleach in the wash will increase the kill rate
- Consider also the cost of laundering:
- Financial
- Environmental (water, electricity, chemicals)
- Time
Sources
- Microbiome analysis and confocal microscopy of used kitchen sponges reveal massive colonization by Acinetobacter, Moraxella and Chryseobacterium species
- The influence of sex, handedness, and washing on the diversity of hand surface bacteria
- Killing of Fabric-Associated Bacteria in Hospital Laundry by Low-Temperature Washing
- Use of quantitative microbial risk assessment for evaluation of the benefits of laundry sanitation
- Effectiveness of Low-Temperature Domestic Laundry on the Decontamination of Healthcare Workers’ Uniforms
- The-infection-risks-associated-with-clothing-and-household-linens
- Cleanliness in context- reconciling hygiene with a modern microbial perspective
- The human skin microbiome
- Microbial biofilms and the human skin microbiome