In the modern world, the importance of infection control in medical, healthcare, and associated settings is well-understood and it should be stringently practised. From the use of surgical masks to infection control gloves, isolating infectious patients to autoclaving instruments (including those used in surgery, dentistry, and even piercing and tattooing), we are getting better at understanding and preventing the transmission of microorganisms that cause disease.
This has not always been the case – and infection control itself is only around seventy years old.
What is Infection Control?
Infection is caused by harmful microorganisms – bacteria, viruses, parasites, fungi, and other toxins. While people have recognised diseases and infections and the fact that they can spread between people for millennia, the cause of them was not understood until quite recently.
The term “infection control” refers to procedures, practices, and policies that are implemented to mitigate the risks of infection in hospitals, other healthcare settings, research laboratories, and places like tattooists to reduce infection rates. It is imperative for the health and well-being of patients, doctors, nurses, other health, science, and associated professionals, and the general public.
A Historical Perspective…
- In the 6th Century BC, ancient Indian physician Sushruta theorised that diseases, fever, consumption, leprosy, and eye conditions spread between people via eating together, sitting together, sleeping together, physical touch and using the same items.
- Instructions are given according to Mosaic Law (in the first five Hebrew Biblical books) regarding washing and quarantine for venereal disease and leprosy.
- Ancient Greek historian Thucydides stated that disease could spread between people via “seeds” of disease through the air.
- The mediaeval Islamic Canon of Medicine, published in 1025, was the foremost medical text in Europe for more than 500 years. It discussed epidemics, contagion theory, contamination of water, food, and garments, and the importance of diet and hygiene.
- German scholar and Jesuit priest Athanasius Kircher observed microscopic “worms” in milk, vinegar, decaying meat, and in the blood of bubonic plague victims (though the latter may have been blood cells themselves).
- Microorganisms were also directly observed in the 1670s when Anton van Leeuwenhoek saw and described yeast cells, bacteria, numerous microorganisms in a droplet of water, and more. He referred to them as “animalcules”. From here, microscopic studies by many early scientists found links between microorganisms and everything from smallpox to ulcerating wounds.
- In 1846, Hungarian physician Dr Semmelweis noted that fewer women died from post-childbirth infection when delivery was by midwives rather than physicians. He studied this phenomenon and concluded that medical students were carrying materials on their hands directly from the autopsy room to the obstetric clinic. Handwashing in a chlorine solution before contact with birthing mothers was implemented and mortality rates dropped.
The Birth of Infection Control…
- Between 1895 and 1900, physicians came to widely understand the benefits of handwashing and other antiseptic techniques in terms of controlling infection and creating better outcomes for patients. A direct link was also identified between hand contamination and faecal-oral transmission and cholera.
- French microbiologist Louis Pasteur discovered that the microorganisms that caused postpartum infection in women could be killed using boric acid, without harming the woman.
- In 1877, it was first suggested that patients with infections be separated from those without, and from here dedicated infectious disease hospitals arose.
- German Robert Koch published criteria in 1884 that established the link between specific microorganisms and diseases.
- In 1910, Barrier Nursing began, and infectious patients were placed in separate wards from others to prevent disease spread. Furthermore, handwashing and equipment cleaning between patients was implemented.
- Formal infection control as we recognise it commenced in the USA in the 1950s when hospitals were plagued by staphylococcal infections. It became widespread and mandated in hospitals in the 1970s. Disease and infection categories were colour-coded, and precautions continued to be recommended for each category of risk. These categories included blood, discharge, wound and skin, respiratory, enteric, protective, and strict.
- Infection control policies evolve, and Universal Precautions were introduced in 1985 in response to the HIV epidemic and many clinical staff becoming infected through accidental needlestick injuries. Regardless of HIV status, all patients were treated following Blood and Bodily Fluid precautions. This included wearing gloves and gowns, as well as eye protection and masks for certain procedures, and each patient had an individual ventilation device if CPR was needed.
Infection control is now based on maintaining barriers or other safeguards between the person with the disease, infection, or pathogen and the clinician, other workers, visitors, and the general public where applicable. It includes but is not limited to isolation, wearing PPE (masks, goggles, gowns, infection control gloves), all bodily substances being considered infectious, Stop Sign Alerts where a patient has an airborne transmissible disease, and staff immunization requirements.
The COVID-19 pandemic further entrenched the need for stringent infection control practices.
In the Era of Antibiotic Resistance…
The development of antibiotics and other antimicrobial agents has arguably been modern medicine’s greatest achievement – but the misuse and overuse of these agents have led to increasing resistance to them by the microorganisms they are intended to conquer.
Millions of people globally are infected with antibiotic-resistant bacteria every year – and many thousands die as a direct result of this. This means that the importance of promoting and maintaining the most effective infection control practices possible is as important, if not more so, than ever.