Being a surgeon, a favorite Simpson’s quote is, “I don’t know why we don’t operate outside more often”. This short clip satirizes the effectiveness of traditional operating room sterile technique.
Most people would consider the operating room the embodiment of sterility. The perception of surgical masks and hand washing provides confidence that this is the best way to avoid infection.
This image may have contributed to the mask requirements during this COVID-19 outbreak. The CDC has recommended that wearing a mask is the most effective way to prevent the spread of disease. However a CDC analysis of 314 patients, 154 COVID-19 positive and 160 COVID-19 negative patients, showed that 71% of positive and 74% of negative participants reported, “always using cloth face coverings or other mask types when in public.” Click here to learn more. In contrast, close contact with one or more persons with known COVID-19 was reported by 43% of positive people, compared to 14% of negative. In the specific subgroup of people who did not have a recent positive close contact, COVID-19 positive participants were more likely than negative participants to have dined at a restaurant or gone to a bar/ coffee shop. This may call to question whether its mask wearing, or simple avoidance of crowds, that is more crucial in avoiding the spread of disease.
Studies assessing the size of the SARS-CoV-2 virus particles may further shed light on its transmission and why common masks are ineffective. Several reports suggest that the virus may primarily exist as small aerosolized particles, which could penetrate a standard mask. Masks may be better designed to block larger droplets. And the mask type matters. Of note, studies indicate that cloth masks made of heavyweight quilter’s cotton with a thread count of 180 or more filter 79% compared to standard surgery masks which filter just 62%. Single lightweight cotton masks are merely 60% efficient. N-95 masks are 95% effective, but require proper fitting, and the CDC recommends against their public use to prevent depletion for health-care workers.
Similarly, hand hygiene is more effective when a virus is transmitted by large droplets. Currently, there is little-to-no evidence that hand washing reduces transmission of SARS-CoV-2.
This research does not suggest that masks or handwashing are useless. The SARS-CoV-2 transmission mode is not fully elucidated and future research may offer different conclusions. These operating room- like practices are unlikely to be harmful and may prevent spread of other viruses like influenza, for which flu season is upcoming. Influenza, in contrast to SARS-CoV-2, may be transmitted by large droplets and stay on surfaces for prolonged periods.
Overall the current literature surely calls to question some of the new mandates Denver has just instituted this past weekend, in response to the 265 new coronavirus cases over the past two weeks.
Interestingly, more rigorous contemporary research casts doubt on the ubiquitous surgical practices of masks and traditional hand washing in the operating room too.
There actually are studies investigating the infection-related surgical outcomes when the surgeon wears a mask versus no mask. No statistically significant association has been identified between wearing masks and decreasing surgical infections. Similarly, there is no clear evidence that surgical masks protect surgeons or staff from body fluid splashes either. As such the National Institute of Health (NIH) guidelines do not require the operating staff to wear a mask in the operating room. However the NIH stresses that mask usage contributes to “maintaining theatre discipline”. In reality, surgeon masks maintain the public’s psyche that masks are associated with safe and proper surgical practice.
Traditionally surgeons scrub their hands with antiseptic soaps, but then paradoxically rinse with standard tap water, prior to being gowned and gloved to start the procedure. That’s right folks… it’s not sterile water outside the operating room. In 2019, the Denver Post revealed that groundwater in metro Denver had up to 2,928 times the federal health advisory limit of PFAS, or “forever chemicals”. PFAS have been linked to numerous adverse health conditions. Research also has discovered that tap water contains tens of millions of bacteria. Most Denverites don’t drink the water with which their surgeon washes his/her hands… One may then hypothesize that a surgeon’s hands could have been cleaner before they scrubbed their hands in preparation for surgery. Luckily, studies suggests that tap water scrubbing is not associated with surgical infections. Infection prevention likely relates more to the use of sterile gowns and gloves, covering those PFAS- and bacteria- laden surgeon hands.
In summary, it is healthy to maintain skepticism towards established beliefs so we periodically re-evaluate their scientific merit. Surgeons, nor any Denver resident, may need to be as concerned about mask-wearing or relentless hand washing in the prevention of surgery-related infections or COVID-19.