Infectious disease continues to exert a heavy burden on health and prosperity. Although the majority of deaths occur in the developing world, infectious disease still causes around 4% of deaths in developed countries and is a significant cause of morbidity. Social, demographic and other changes mean that the importance of hygiene in home and everyday life is increasing rather than decreasing.
Food, waterborne and non-food-related infectious intestinal diseases remain at unacceptable levels. Despite people’s general belief that foodborne infections occur outside the home, data collected from 18 European countries, suggests that about 31% of foodborne outbreaks occur in private homes. Norovirus, mainly spread from person-to-person, is the most significant cause of intestinal infections in the developed world, including 3 million cases per year in the UK, whilst rotavirus is the leading cause of gastroenteritis in children under 5.
On average, adults get 4 to 6 colds per year, while children get 6 to 8. Respiratory hygiene can limit spread of respiratory infections, particularly colds, but also influenza. Since respiratory and intestinal viral infections are not treatable by antibiotics, prevention through hygiene is key.
Governments, under pressure to fund the level of healthcare that people expect, are looking at prevention as a means to reduce health spending. Increased homecare is one approach to reducing health spending, but gains are likely to be undermined by inadequate infection prevention and control at home. Healthcare workers now accept that reducing the burden of infection in healthcare settings cannot be achieved without also reducing the circulation of pathogens such as norovirus and MRSA in the community.
Societal changes mean that people with greater susceptibility to infectious disease make up an increasing proportion of the population, up to 20% or more. The largest proportion comprises the elderly who have reduced immunity, often exacerbated by other illnesses. It also includes the very young, and family members with invasive devices such as catheters and people whose immuno-competence is impaired as a result of chronic and degenerative illness (including HIV/AIDS), or drug therapies such as cancer chemotherapy.
Emerging pathogens and new strains are a significant concern. It is remarkable that norovirus, Campylobacter and Legionella were largely unknown as human pathogens before the 1970s, with others such as E.coli O157 and O104 emerging in subsequent decades. Agencies worldwide recognise that, for threats such as new influenza strains, SARS and Ebola, hygiene is a first line of defence during the early critical period before mass measures such as vaccination become available. The low infectious dose observed for several of the emerging pathogens, such as E.coli O157:H7 and norovirus, is an additional concern that emphasises the role that hygiene can play in prevention.
Antibiotic resistance is now a global priority. Hygiene addresses this problem by reducing the need for antibiotic prescribing and reducing “silent” spread of antibiotic resistant strains in the community and hospitals. As persistent nasal or bowel carriage of these strains spreads in the healthy population, this increases the risk of infection from resistant strains in both hospitals and the community.
The 2019 UK National Action plan on AMR says “Health & social care providers can only do so much to prevent infections; when it comes to infections in the community (which requires exposure to antimicrobials), the public have a huge part to play”.
Infections can act as co-factors in diseases, such as cancer and chronic degenerative diseases. Syndromes such as Guillain-Barré and triggering of allergy by viral infections add to the burden of hygiene-related infection.