Infection control is an age-old problem. Before antibiotics became widely available in the 1940s, it was common for infection of a minor wound to cause serious illness or even death.
But antibiotics have become less effective as bacteria evolve and become resistant to them. While the search for new antibiotic drugs continues, scientists and medics are taking inspiration from past treatments and approaches to limit infection.
Taking a second look at historic treatments
Ancient cultures used lots of substances to treat bacterial infections—from moulds and soil to honey and wine—with varying levels of success. Today, ethnopharmacologists study historic medicines to understand how these treatments work and find out if the active ingredients present in them could be the basis for new medicines.
A recipe for ‘eye salve’ from a 1,000-year-old Anglo-Saxon medical textbook called Bald's Leechbook states onion, garlic, wine and cow's bile should be crushed together and left in a bronze vessel for nine days and nights. In lab tests, researchers from the University of Warwick found the remedy kills the bacteria MRSA faster than any antibiotic.
A study looking at the use of dressings containing honey found they are more effective than well-established dressing made with silver that are used to treat burns. The burns treated with honey dressings healed faster and with lower infection rates. This was attributed to honey’s antioxidant and anti-microbial properties.
The importance of ventilation
Miasma theory is an abandoned medical concept that was popular from the Middle Ages until the late 1800s. It stated diseases were caused by a noxious form of "bad air" known as a miasma. We now understand infections and disease are caused by microscopic organisms that can travel in the air, not the air itself.
Miasma theory led to positive advancements in medicine, although for the wrong reasons. By removing bad smells through cleaning, opening windows and getting patients to ‘take the air’, hospitals often inadvertently removed microorganisms which cause disease, decreasing the chances of infection.
Pioneer nurse Florence Nightingale (1820–1910) firmly believed in miasmas and became celebrated for her work in making hospitals clean, fresh and airy.
Over the last 100 years, many hospitals have been sealed back up. Airtight doors are fitted between wards to prevent patients in one area infecting people in other parts of the building. Modern hospitals are ventilated using air conditioning, which recirculates air rather than drawing in fresh air from outside. This helps keep a hospital warm but allows infectious microorganisms to circulate within wards.
Ventilation is one of the most important ways to control cross-infection. Greater ventilation rapidly reduces concentrations of disease particles in the air and thereby infections in surrounding patients.
Simple, low-cost ventilation designs and configuration of wards can reduce the dispersal of airborne virus in emergency COVID-19 hospitals.
Professor Andrew Woods, BP Institute, University of Cambridge
Cleaning hospitals: Innovations with copper and UV light
Antibiotic resistant bacteria, like MRSA, have become progressively more common in places like hospitals. As a result, it has become increasingly important to limit how much patients come into contact with, and risk being infected by, bacteria in these settings.
The metal copper is well-known to neutralize microbes. In 2007 a study of eight intensive care unit rooms where copper bedrails, tray tables, intravenous poles and chair armrests were installed showed infections in these rooms dropped 58% compared to unmodified rooms.
Some hospitals in England are slowly converting their operating theatres to have copper panelling. Copper alloys are being used in hospital surfaces like railings. as well as rarely washed utensils like IV drip stands, stethoscopes, and even pens.
Researchers studying COVID-19 noted that the virus lasts for several days on stainless steel, which most hospital surfaces are made from, but dies within hours on copper.
The ultraviolet light in sunlight has long been understood as a way to stop bacteria growing. In 1890 Danish physicist Niels Ryberg Finsen developed the first carbon arc lamp, which produced ultra-violet light artificially and much more conveniently. Finsen was awarded the Nobel Prize for Medicine after proving his lamp could treat Lupus vulgaris, a rare form of tuberculosis that caused skin lesions. Shining the ultraviolet light onto patients’ skin killed the tuberculosis bacteria that cause the condition.
More recently, ultraviolet light has been explored as a way to kill disease-causing organisms on surfaces. In 2019 a study in New York showed that ultraviolet disinfection, shining a UV lamp slowly over surfaces, eliminates up to 97.7 percent of pathogens in an operating room. Ultraviolet disinfection could be a chemical and fume-free way to disinfect hospitals in the future.
Find out more
- The History of Germ Theory by Jemima Hodkinson, in Big Picture
- ‘On the Effects of the Antiseptic System of Treatment’, Joseph Lister, 1870
- Antiseptic Surgery: Its Principles, Practice, History and Results by William Watson Cheyne, 1882
- ‘Asepsis and Bacteriology’ by Thomas Schlich
- 'One False Move', 1963 public information film (video)