Infection control is a vital pillar in reducing the spread of contagious diseases in Optometry practices. Since patients and practitioners are in close proximity, there is a high potential for the transfer of contagious diseases.
Infection control aims to reduce the spread of infections like the common cold, especially in prodromal phases where no symptoms are present. Eye-related infections like adenovirus and those related to contact lens wear are minimised as well.
If you are an Optometrist or a member of the community, this will be beneficial for education and implementing strategies for both work and home.
Most of this information is sourced from Infection Control Guidelines for Optometrists 2016.
Proper Hand Washing Technique
- Remove jewelry1
- Wet hand by running through warm water
- Use liquid soap from a dispenser (bar soap can harbor microbes) and lather onto hands
- Rub hands for 20 seconds (sing happy birthday to yourself twice), creating bubbles
- Rub both sides of hands
- Wash between fingers and thumb
- Rub fingertips on palms
- Rinse under warm water to clear off
Hand washing2 is considered the most appropriate method for controlling the spread of infections in Optometric practice.
Hand washing works by creating friction which removes microbes off the surface of the hands3. The microbe particles are then washed away by water.
Although alcohol-based hand runs are considered the gold standard of care in hospitals. They are not suitable as the only method of hand cleaning in the Optometric office, especially with contact lens usage.
This is because alcohol hand rubs are ineffective against non-enveloped viruses (e.g. norovirus), certain bacterial spores (e.g. Clostridium difficile – causes infection of the gut), which are better washed off by hand washing. This is also the case with Adenovirus and Protozoan cysts like acanthamoeba.
Alcohol rubs cannot substitute hand washing in removing dirt from hands, which are better removed by friction of lathering soap and rinsing with water.
Additionally, remaining alcohol when the patient inserts the contact lenses can be extremely painful!
A good rule: if you have access to hand washing, use it. If not, alcohol rubs are the next best method.
Personal Protective Equipment
Gloves, in particular those made from nitrile, as latex can result in skin allergy, should be used in cases where there is a high chance of spread of diseases such as hepatitis. Also, if the practitioner has any cuts or wounds on their hand, this would be a good case to use gloves.
Powder-free gloves should be used, as the powder in the gloves can be introduced into the air and become an agent of infectious transfer4. Power is really there to allow easy application and removal of gloves, but reducing contamination far outweighs this.
New gloves should be used for every single instance and when removing gloves the user must wash their hands. Gloves do not replace hand washing.
Face shield or mask with safety eye goggles should be used where there is a high chance of airborne infection.
Surgical masks should be worn in the case by the patient and practitioner if one of them has a cold of influenza. The mask must be replaced when it has become moist.
The most effective method is always the most desirable; however, we have to work within the reasons of practicality. For example, sterilisation is the best method for removing any agents of infection. But good luck putting your entire slit-lamp into an autoclave, let alone survive the high-pressure sauna.
For equipment that touches the skin, a low-grade or intermediate-grade disinfectant can be used. An example of this type of equipment would be the chin rest of the slit lamp, trail frame, or keyboard that you use in the office.
Isopropyl alcohol at a percentage of 70% is a good example of an appropriate disinfectant. The percentage is an important factor. The concentration of alcohol, in this case, propan-2-ol, must be high enough to have an effect. The 30% of water required for dilution is also for bactericidal properties. The water allows the alcohol component to penetrate the cell wall of bacteria, allowing the alcohol to dissolve the cell membrane of the bacterial cell5.
For the equipment that touches the mucosal tissue (such as the cornea, conjunctiva – these tissues constantly secrete fluids). Disinfection is appropriate by using either 3% hydrogen peroxide (H2O2) or 5% household (NaOCl) bleach. For example, this is the case with a tonometry probe, which can be destroyed when put through an autoclave. Soaking the tonometry probe tip for 10 min in either hydrogen peroxide or diluted bleach is a form of high-level disinfection. Too long can result in damage to the probe.
Soaking between patients would be enough time but not too long for damage. Avoid soaking the probe at the end of the day and remember to wash the probe with saline at the end of the day and store in a dry place.
For equipment that breaks tissues, like an Algerbrush burr, this will have to be either discarded if it is one-time use or sterilised.
Sterilisation involves using an autoclave. The autoclave is able to reach a pressure of 106 kPa (1 atm) and a temperature of 121 °C for a time of 15 to 30 minutes. Sterilsation involves the killing and removal of all organisms as opposed to disinfection which removes not all but a majority of harmful microorganisms6.
Now, I’m betting most practices do not have an autoclave on standby – I certainly haven’t worked at a place that does. However, your local doctors or dentist should be able to sterilse your equipment, if you ask kindly of course. I have two burrs. I use one and alternate. It pays to have redundancy.
This is a simple guide to infection control for the optometry clinic and I am hoping that it gives you a rough guide in reducing spread of disease within the clinic. I would encourage you to read the paper mentioned earlier as it covers this in greater detail. I have not covered everything, only the basics.
Proper handwashing is the most appropriate way of reducing infection spread. It is valuable in its low cost and ease.
Having a stock of appropriate personal protective equipment is an appropriate way to reduce infection in close contact with patients.
A table below summarises the level of disinfection and sterilisation required for certain equipment.
Please comment and let me know if you have any questions or would like to discuss this further.
- Hand hygiene: Back to the basics of infection control
- Hand washing | Ministry of Health
- FAQs | The Global Handwashing Partnership
- Advantages of Powder Free Gloves – AMMEX
- Why 70% Isopropyl Alcohol (IPA) is used as Disinfectant in Pharmaceuticals? : Pharmaceutical Guidelines
- Sterilization and Disinfection – an overview | ScienceDirect Topics