Infection risk
Infection risks include domestic hygiene, pests, refuse, food safety, personal hygiene, sanitation, drainage and water supply.
Types of infection risk
15. Domestic hygiene, pests and refuse
Most vulnerable: All age groups
This category covers hazards which can result from:
- poor design, layout and construction such that the dwelling cannot be readily kept clean and hygienic
- access into, and harbourage within, the dwelling for pests
- inadequate and unhygienic provision for storing and disposal of household waste
Please note that hazards associated with sanitation and drainage, domestic water, personal washing facilities and food safety should each be dealt with as separate hazards.
Effects
The potential health outcomes are gastro-intestinal disease (from spread of infection), asthma and allergic rhinitis (from allergens). Household waste may also cause a risk of cuts to young children. Areas which are difficult to keep clean may be a cause of depression and anxiety.
Emotional distress is also commonly associated with pest infestations, and accumulations of refuse. Insect pests can cause allergic reactions. Children who live in dwellings visibly infested with cockroaches show high levels of sensitivity to cockroach allergen. Contact with cockroaches can cause dermatitis, urticaria, rhinitis, bronchitis and asthma. Anxiety may also be experienced by people with a phobia of the insects.
Birds, such as pigeons, can cause nuisance, carry diseases including Salmonella and can harbour biting insect pests such as the Martin Bug in their nests.
All age groups may be vulnerable to infections associated with dirt, dust and those passed on by pests. Young children may be the most vulnerable to infection and cuts associated with poorly stored refuse, through lack of awareness of dangers. Asthmatics and those with pest allergies will be most vulnerable to allergic reactions to pests.
16. Food safety
Most vulnerable: Infants, young children, pregnant women and the elderly
This category covers threats of infection resulting from inadequacies in provision and facilities for the storage, preparation, and cooking of food.
Effects
Foods (including liquids such as milk) can become a source of food poisoning through contamination, the multiplication of micro-organisms through poor or inappropriate storage, or through inadequate cooking.
Illnesses resulting from food poisoning range from mild stomach upset through to death from infectious gastro-intestinal disease, or hospital admission because of severe diarrhoea, vomiting and dehydration. However, most mild gastro-intestinal infections caused by food poisoning go unreported (and so are not included in statistical evidence).
It is estimated that in the general UK population there are 86,000 cases of food poisoning annually (just over half are formally notified and data on the others is from other sources). It is estimated that at least 50% of these cases arise in the home, with some estimates putting the figure even higher – 86% for Salmonella and 97% for Campylobacter.
Food poisoning impacts all age groups in all types of dwelling. However, those most susceptible are the young, especially infants, the elderly and pregnant women. These groups may also suffer more severe outcomes.
17. Personal hygiene, sanitation, and drainage
Most vulnerable: People who are immunocompromised, the elderly and children under 4
This category covers threats of infection and threats to mental health associated with personal hygiene, including personal washing and clothes washing facilities, sanitation, and drainage.
Effects
The health outcomes from both poor personal hygiene and poor sanitation include gastro-intestinal illness, and, more rarely, skin infections. Illnesses resulting from gastrointestinal infection can range from mild stomach upsets through to death from diarrhoeal and gastro-intestinal disease, severe dysentery, and gastro-enteritis.
There are between 2,000 and 20,000 notified cases of dysentery each year and in excess of 80,000 cases of viral gastro-enteritis. It is not clear how many of these are related to sanitation and drainage, whether domestic or elsewhere. Dysentery (Shigella sonnei) and rotavirus infections are frequent causes of diarrhoea carried by the faecal-oral route. Even if the illness is contracted elsewhere up to 50% of family members may become infected if hygiene levels are poor.
Although not a direct cause of physical illness, odours associated with poor hygiene, the visual appearance of facilities which are difficult to clean or have stained surfaces, damaged decoration and furnishings resulting from splashing or leaking appliances or drainage, can be a cause of stress and depression. This is particularly the case where the occupant has little control over the situation, typically in rented accommodation, and where facilities are shared. As well as causing anxiety and depression, it can also cause tension between people sharing facilities.
18. Water supply
Most vulnerable: All age groups
This category covers the quality and adequacy of the supply of water within the dwelling for drinking and for domestic purposes such as cooking, washing, cleaning and sanitation. As well as the adequacy, it includes threats to health from contamination by bacteria, protozoa, parasites, viruses, and chemical pollutants.
Effects
Water is essential to sustain life. At normal temperature, with little or no exercise, an adult needs to consume around 2.5 litres of fluid each day, but in hot conditions and with heavy exercise the output rises substantially. Mild dehydration is associated with fatigue, headaches, dry skin, constipation, bladder infections, and poor concentration.
In the UK, the main threats to health from water result from contamination. Microbiological pathogens which affect drinking water typically cause gastro-intestinal illness. Campylobacter and Cryptosporidium are the most common causes of gastrointestinal illness associated with drinking water. Legionella, which typically causes respiratory infection, also presents an infection risk from domestic water systems. Young children and the immuno-compromised are most at risk from ingested pathogens, and the elderly and immuno-compromised are most at risk from Legionella.
Private water supplies may be untreated and can become contaminated more readily, although there is a lower rate of reported illness. While this may be due to the occupiers developing some acquired immunity, visitors may be at risk.
In 2000 there were 173 reported cases of Legionnaires’ disease, of which 76 (44%) were community acquired. It is estimated that 1 in 6 community acquired cases is due to domestic water systems. Most infections with Legionella’s are respiratory infections, acute pneumonia – Legionnaires disease – of which 10 to 15% of cases are fatal. Legionella can also cause wound infections from contact with contaminated water.