Bathroom and toilet hygiene in the home
The bathroom and toilet are communal areas of the home which are in constant use
throughout the day. They thus offer constant opportunities for spread of infection
from one family member to another if basic hygiene standards are not observed. This
leaflet has been put together to provide background information on bathroom and
toilet hygiene with particular reference to the home. This briefing material has been
produced for healthcare professionals, the media and others who are looking for
background understanding and/or are responsible for informing the public about
infectious diseases in the home and their prevention through good hygiene practice.
The bathroom and toilet are communal areas of the home which are in constant use
throughout the day. Bathroom and toilet areas usually have higher levels of moisture
in the atmosphere and on surfaces than the rest of the house. Given that there will
also almost always be some residual nutrients from organic matter, this provides
good conditions for micro-organisms to survive for extended periods, and in some
circumstances microbial populations can grow and form permanent reservoirs of
infection. The bathroom and toilet provides an ideal environment for spread of gut,
respiratory and skin pathogens via hands and surfaces.
How do pathogens get into the bathroom and toilet?
The source of pathogenic (harmful) micro-organisms in the bathroom and toilet is
almost entirely from people. In particular:
Stomach bugs such as Salmonella, Campylobacter, norovirus, Escherichia
coli O157 and other pathogenic strains of E. coli from an infected person (or a
carrier) are shed into the toilet via their faeces. Contamination may also remain
on the hands, if they are not washed after toilet visits. As outlined below the risks
are greatest when a family member is vomiting, or has fluid diarrhoea, but people
may continue to shed gut pathogens in their faeces for some time after their
symptoms have ceased. Family members can become infected if they touch their
mouth with contaminated hands or, if ready-to-eat food such as sandwiches are
prepared by someone with contaminated hands. In the case of norovirus
infection, where the infected person vomits in the confined closed area of the
bathroom or toilet, inhalation of the aerosolised particles can cause infection.
Skin pathogens such as Staphylococcus aureus (including methicillin resistant
S. aureus (MRSA)) are shed in large numbers from the skin. Up to 60% of the
population may carry S.aureus as part of their normal resident skin flora. Carriers
of S. aureus shed the organism from the skin’s surface, most usually associated
with skin scales. The rate of shedding increases when people remove their
clothes, take a shower, or dry themselves with a towel. This is because the skin
friction increases detachment of skin scales. If S. aureus comes into contact with
cuts, abrasions, or with ulcerated skin, or the skin of someone with psoriasis or
eczema, it can produce septic infections, or, more seriously, can enter the blood
stream causing bacteraemia. The bathroom and toilet provides an ideal
environment for the spread of skin pathogens via hands, bathroom and toilet
surfaces, and towels and face cloths. Of increasing concern are the emerging
“community-associated” strains of S. aureus, some of which are methicllin
resistant, whilst others can carry the PVL toxin which can cause severe
necrotising (flesh-eating) infections. For more information of S. aureus and MRSA
consult the IFH information and hygiene advice sheet “Methicillin Resistant
Staphylococcus aureus (MRSA) and the home”.
Respiratory viruses such as cold and flu viruses are shed in large numbers in
nasal and other secretions produced by coughing, sneezing and nose blowing by
an infected person. The bathroom and toilet provides an ideal environment for the
spread of respiratory viruses via hands and hand contact surfaces. Family
members can become infected if they rub their eyes or nose with contaminated
In addition, airborne fungi which enter the bathroom can colonise moist (particularly
damaged) surfaces. This fungal growth is not infectious but can release spores or
substances which trigger respiratory allergies such as asthma.
Showerheads can act as a source of potentially harmful microbes such as
Legionella or Pseudomonas. These may be present in household water supplies
and although, under most circumstances they are harmless, Legionella can cause
respiratory infections when contaminated water is aerosolised (during showering),
and the aerosol is inhaled by the person taking a shower. These microbes are more
likely to grow in stagnant water and where scale or scum (biofilms) has formed. The
risk is thus increased if the shower is used only occasionally, or when it is used for
the first time after a break.
It is important to be aware that we all, all the time, carry millions of microbes in our
gut, in our mouths and on our skin, which are constantly shed into the environment.
The toilet routinely receives large quantities of bacteria, up to 1010/g of faeces. Where
studies of the home are featured in the media, they frequently report that “millions of
germs” were located on surfaces such as the toilet seat. Bear in mind however that
the majority of these microbes are harmless to normal healthy adults. Because it is
difficult to demonstrate the presence of pathogens such as Salmonella or norovirus in
the home environment, unless we investigate homes where there is a known infected
person, we often use “faecal coliforms” or “faecal streptococci” as indicators of
infection transmission risks. All of us carry these organisms in our normal gut. This
means that, if we find these organisms on environmental surfaces, it is an indicator of
poor “toilet hygiene”, that is, it indicates that if a family member was carrying a
pathogen in the gut, there is a risk that this organism could be found in the home
How do pathogens spread in the bathroom and toilet cause infection?
Toilets are a potential source of infection because they are contaminated with
microbes from the gut every time they are used for defacation. Being wet provides
ideal conditions for the survival and growth of microbes. Flushing the toilet efficiently
removes most organisms. If not regularly decontaminated, however, residual
organisms from an infected person can survive in significant populations, even for
weeks if protected by biofilms or limescale (e.g. Salmonella has been shown to
survive in the scaly biofilms on the surface of the toilet for at least 6 weeks after an
infection has occurred in the home. In this case the organism was found under the
flushing rim and in the scale on the porcelain surface of the toilet). The risks from the
toilet are assessed as follows:
In general, the risk from the toilet bowl itself is not high, because the organisms
are removed by flushing and or cleaning the toilet. However the hands can
become contaminated during toilet cleaning. or when children decide to
Splashing and aerosol formation can occur during toilet flushing. Splashes will
transfer organisms to the seat and lid, whilst aerosol particles can travel greater
distances and can settle not only on the toilet seat and lid but also other
bathroom surfaces such as the toilet flush handle, tap handle, door handle, as
well as basin and bath surfaces, or even items such as toothbrushes. People can
pick these up on their hands and can be infected by direct hand to mouth transfer
or by handling or preparing ready-to-eat foods.
It is hard to quantify the risks of transfer from the toilet to surfaces such as basin taps
and toilet flush handles (or door handles if the toilet is in a separate room). The data
show that the risk of spread arising from splashing and aerosols transmission from
the toilet is increased if an individual within the household has diarrhoea. There is
also potentially a greater risk of spread from babies and toddlers with diarrhoea
because they have no control over their bowels and they rely on others to meet their
hygiene needs. The same applies to older children and adults who lose their ability
to maintain their own hygiene or lose bowel control due to infection, ill health or age.
Baths and hand basins
Microbes such as S. aureus, from the skin, or gut microbes removed from the body
during bathing or handwashing, can survive in the damp scum or scale left behind on
the surfaces of the bath or hand basin. These organisms may be transmitted to
others by direct contact, or by transfer via hands to other surfaces.
The U-bends and plug holes of baths and hand basins are a breeding ground for
microbes which can include potentially pathogenic species such as Pseudomonas
aeruginosa. Hospital investigations have shown that “splash back” from the plug hole
can lead to contamination of the sink and bath surface. However these organisms
are not usually harmful, except to family members with poor infection immunity. P.
aeruginosa readily infects patients with cystic fibrosis
In situations where showers are not properly maintained there is a risk that the
shower head can become a source of aerosolised bacteria such as Legionella -
particularly where stagnant water is allowed to build up in the system if the shower is
unused for a period. They can be transmitted to others by inhalation of aerosols
generated from the water and can cause infection.
If used by an infected individual, the shower tray can allow survival and transfer of
fungi such as those that cause athlete’s foot. The shower walls and curtain also
provide ideal conditions for growth of fungi which, though not infectious, may be
hazardous by releasing spores or substances which trigger respiratory allergies such
Cleaning cloths and other cleaning utensils
Cleaning utensils, and cloths and mops in the bathroom or lavatory, particularly if left
damp, can support the growth of microbes, which become firmly attached to the cloth
or other surface. Contaminated cloths and utensils readily spread germs from one
place to another. They should be decontaminated after each use.
Towels and face cloths
Towels and facecloths are often moist enough to support the growth of populations of
bacteria, although bacterial species which readily grow in this situation are normally
harmless. Whilst harmful bacteria do not usually grow outside the human body, they
can survive for considerable periods of time on damp towels etc. and sharing such
items with an infected person may provide the opportunity for cross-infection. Face
cloths, towels and nailbrushes, if used by an infected person, thus provide a route for
transferring pathogens to other family members.
Who is at risk?
Although the bathroom and toilet offer constant opportunities for spread of infection
within the family, it is difficult to assess the extent to which infections arise as a result
of poor hygiene. For the normal healthy adult, the risks of infection from exposure to
microbes in this environment are relatively small but:
Any home is likely to contain one or more people who are at increased risk of
infection because their immune system is not functioning at full strength. This
includes the very young and the elderly together with people who have an
underlying medical condition or who are taking drugs which reduce their immunity
to infection. For example:
- People with wounds, catheters or other invasive devices that break the skin
may be at risk from contact with dirty baths, showers and whirlpool baths.
- People with underlying respiratory conditions, such as cystic fibrosis, and
older people are at increased risk of infection caused by aerosolised
microbes disseminated by showers and whirlpools.
- People who are suffering from diarrhoea and vomiting spend a lot of time in
the bathroom and are likely to leave behind pathogens (bacteria or viruses)
in the toilet, the air and on surfaces. Remember that people, particularly
visitors to the home, are reluctant to say that they have diarrhoea.
Although most strains of S. aureus are relatively harmless to the healthy
individual, one of the key characteristics of the “newer” community-acquired
MRSA and PVL-producing strains is that infections with these strains are more
prevalent among children and young adults where they cause infections of the
cuts, wounds and abrasions that children and young adults constantly acquire
through play and contact sports. Fortunately, community-acquired (CA) MRSA
strains are resistant to fewer antibiotics than hospital-acquired MRSA, with the
consequence that these infections are readily treatable - provided doctors are
aware that the patient might be carrying a CA-MRSA strain.
Preventing the spread of infections in the bathroom and toilet
Since the risk of introducing pathogenic microbes into the bathroom and toilet is
constant and may not be recognised until an outbreak of infection occurs within the
family, this means that good day-to-day hygiene makes sense. Although for much of
the time, microbial risks in the bathroom and toilet are limited because the microbes
are relatively harmless to the healthy adult, it is still considered good practice to keep
these areas clean (i.e. remove dirt) and dry. By eliminating the breeding ground for
germs, the microbial risks are reduced.
The biggest infection transfer risk in the bathroom and toilet comes from the hands
and from surfaces, which are constantly touched by family members, such as taps,
the toilet flush handle, toilet seat and lid, and door handles. It also comes from cloths
and other cleaning utensils which can spread bacteria and viruses from one surface
to another. Sharing of towels, facecloths and other personal care items increases the
risk of spread of skin and eye infections. For some bacteria, and particularly viruses,
the ‘infectious dose’, i.e. the number of organisms required to cause an infection if
ingested or introduced into a cut or abrasion, can be very small and whilst a healthy
adult can be resistant to quite a large dose of Salmonella, this may not be the case
for those with reduced resistance.
The following hygiene measures are recommended to reduce the risk of infection
transmission in the bathroom and toilet. In situations where there is more risk (i.e.
where there is someone who is infected or someone who is more vulnerable to
infection) the basic hygiene practices are the same. The major difference is that, if
hygiene procedures are not followed, the risk of infection is much greater.
Good handwashing practice is the single most important infection control
measure. Hands should be thoroughly washed with soap and running water* after
using the toilet. In “high risk” situations where there is an outbreak of infection in
the home, it is suggested that handwashing followed by use of an alcohol
rub/sanitiser should be encouraged.
Keep the toilet bowl clean by flushing after use. Clean regularly using a toilet
cleaner. Remove scale using a descalent product. If someone has diarrhoea,
toilets etc. should be disinfected after each time they use it. Wash your hands
after cleaning the toilet. When there is an outbreak of gut infection in the home,
thorough cleaning, descaling and disinfection of the toilet is important, not only
during the diarrhoea/vomiting phase of illness, but also for at least two weeks
after symptoms have subsided.
Hygienically clean baths, wash basins and shower trays regularly. This can be
achieved by cleaning with a detergent cleaner followed by thorough rinsing with
running water. Alternatively use a disinfectant cleaner which is effective against
bacteria and viruses**. This is very important after use by a person who is
infected, or if a surface is contaminated with vomit or faeces. Since microbes tend
to form as biofilms in u-tubes and plugholes, which are difficult to remove,
disinfection is needed in risks situations where decontamination of these sites is
Hygienically clean surfaces in the bathroom and toilet regularly, with particular
attention to toilet seats, toilet handles and other hand contact surfaces. Use a
disinfectant cleaner which is effective against bacteria and viruses**.
Cleaning cloths can easily spread microbes around the bathroom and toilet. They
should be hygienically cleaned after each use. This can be done in any of the
- wash in a washing machine at 60C (hot wash)
- clean with detergent and warm water, rinse and then immerse in a
disinfectant solution which is effective against bacteria and viruses for at least
20 minutes or as prescribed
- clean with detergent and water then immerse in boiling water for 20 minutes.
Alternatively use disposable cloths.
- Never use the same cloth in the kitchen as in the bathroom and toilet
Where floors or other surfaces become contaminated with faeces or vomit, they
should be hygienically cleaned at once:
- Remove as much as possible of the excreta, from the surface using paper or
a disposable cloth, then
- Apply disinfectant cleaner** which is effective against bacteria and viruses to
the surface using a fresh cloth or paper towel to remove residual dirt – then
- Apply disinfectant cleaner** to the surface a second time using a fresh cloth
or paper towel to destroy any residual contamination
Disposable gloves should be worn if in contact with faeces, and hands should be
washed after removing gloves.
If someone has vomited in the toilet or bathroom, if possible, vacate the room and
ventilate by opening windows for a short time to disperse aerosol particles
Towels and face cloths should be regularly laundered using a laundry cycle which
will remove/destroy any pathogenic organisms. Either:
- For preference, wash at 60C or above using any laundry product as heat will
destroy bacteria and viruses.
- Wash at 40C using a bleach-containing laundry (powder or tablet) product.
Note: washing at 40C without the presence of a bleach will not destroy bacteria
Do not share towels, facecloths, toothbrushes and other personal hygiene items
with the infected or carrier person.
If the shower has not been used for a long period of time, leave it to run at a hot
temperature for a few minutes before use
Make sure that tiles and grout are in good condition and are regularly cleaned. An
anti-fungal cleaner may be needed.
Hygienically clean or launder shower curtains regularly
*How to wash hands:
Handwashing “technique” is very important. Rubbing with soap and water lifts the
germs off the hands, but rinsing under running water is also vital, because it is this
process which actually removes the germs from the hands. The accepted procedure
for handwashing is:
Ensure a supply of liquid soap, warm running water, clean hand towel/disposable
paper towels and a foot-operated pedal bin.
Always wash hands under warm running water.
Rub hands together for 15–30 seconds, paying particular attention to fingertips,
thumbs and between the fingers.
Rinse well and dry thoroughly.
In situations where soap and running water is not available an alcohol-based hand
rub or hand sanitiser should be used to achieve hand hygiene:
Apply product to the palm of one hand.
Rub hands together.
Rub the product over all surfaces of hands and fingers until your hands are dry.
Note: the volume needed to reduce the number of germs on hands varies by product.
In high risk situations where there is an outbreak in the home, handwashing followed
by use of an alcohol rub/sanitiser should be encouraged.
One very simple thing which people can do which can significantly reduce the risk of
disease is to avoid putting their fingers to their mouth.
**Disinfectants and disinfectant cleaners
For preference use a disinfectant or disinfectant/cleaner such as a bleach-based
product, which is active against viruses as well as bacteria. For more details on
choosing the appropriate disinfectant, see the IFH information sheet “Cleaning and
disinfection: Chemical Disinfectants Explained”. Consult the manufacturers’
instructions for information on the “spectrum of action”, and method of use (dilution,
contact time etc). For bleach (hypochlorite) products, use a solution of bleach, diluted
to 0.5% w/v or 5000ppm available chlorine. Household bleach (both thick and thin
bleach) typically contains 4.5 to 5.0% w/v (45,000-50,000 ppm) available chlorine.
Where “concentrated bleach” is recommended a solution containing not less than
4.5% w/v available chlorine should be used. Bleach/cleaner formulations (e.g.
sprays) are formulated to be used “neat” (i.e. without dilution).
When using a disinfectant, It is always advisable to check the label as concentrations
and directions for use can vary from one product to another.
IFH Guidelines and Training Resources on Home Hygiene
1. Guidelines for prevention of infection and cross infection the domestic
environment. International Scientific Forum on Home Hygiene. Available from:
2. Recommendations for selection of suitable hygiene procedures for use in the
domestic environment. International Scientific Forum on Home Hygiene.
Available from: http://www.ifh-
3. Guidelines for prevention of infection and cross infection the domestic
environment: focus on issues in developing countries. International Scientific
Forum on Home Hygiene. Available from: http://www.ifh-
4. Home Hygiene - prevention of infection at home: a training resource for carers
and their trainers. International Scientific Forum on Home Hygiene. Available
5. Home Hygiene in Developing Countries: Prevention of Infection in the Home
and Peridomestic Setting. A training resource for teachers and community
health professionals in developing countries. International Scientific Forum on
Home Hygiene. Available from: http://www.ifh-