Have you ever wondered how far a sneeze might travel if you weren't wearing a mask or didn’t sneeze into a tissue?
It’s further than you might think, and this can have real health and safety implications for the people with whom we share our indoor space, even when standard COVID-19 protocols are in place.Winter is definitely on its way to us, and South Africa (usually) experiences an annual winter flu epidemic. And with the flu comes sneezing, coughing and congestion, to name just a few of the common symptoms. According to the National Institute for Communicable Diseases (NICD) the timing of our flu season varies slightly from year to year but usually occurs between May and August, with an average duration of around 19 weeks.
However, did you notice that I said, “usually experiences an annual winter flu epidemic”? Thanks to anti-COVID efforts, experts said that South Africa "didn't have a flu season’ in 2020.
Covid-19 and the 2020 flu season:
South Africa usually records around 11,000 deaths annually from flu through advanced flu monitoring surveillance programs. Three separate labs screen people at random and usually record more than 1,000 flu cases. In 2020 there was only one reported case of the flu virus from those labs.
"What happened was completely unprecedented and unexpected," said Dr. Cheryl Cohen, co-head of the NICD's Centre for Respiratory Disease and Meningitis. She believes that pandemic protection measures - such as social distancing, hand sanitisation and masks - made a real difference and that sticking with these anti-COVID-19 measures, "should hopefully reduce flu" this coming winter.
Reducing the spread of the flu this winter is an excellent goal, but we can’t afford to get complacent regarding the spread of COVID-19 either. More than 1.5 million cases and more than 50,000 COVID-19 deaths have been confirmed in South Africa to date, and the true number of cases is likely to be in excess of 10 million.
Sneeze particles and their range:
Both COVID-19 and the flu virus are present in the nose and mouth of an infected person. When sick people cough, sneeze, laugh or talk, they spread thousands of droplets containing as many as hundreds of millions of infectious particles into the air or onto surfaces.
But how far can those infectious particles really travel if you sneeze and you aren't wearing a mask? Or if your hand, handkerchief, tissue (or even elbow, in a pinch) didn’t catch your sneeze? Is the social distancing distance of 1.5 meters apart enough to prevent infectious droplets from entering our breathing zone and making us sick? (In our previous blog post on the design of the new VIRUSKILLER™ air purifier, we discussed the "breathing zone" which is conventionally defined as the zone within a 20 - 25cm radius of a worker's nose and mouth.)
It all depends on size
The droplets ejected at high speed from a cough or sneeze vary in size from a few thousandths of a millimetre to a couple of millimetres. The larger ones fall within a metre or so, but many are small enough to float through the air around you, entering your breathing zone.
Differing opinions on range
Experts do seem to be divided on just how far the smaller droplets, especially, can travel.
- The UK NHS says the droplets “typically spread about one metre”
- The US CDC says about two metres
- Research done at MIT in 2014 a lab using high-speed cameras and mathematical modelling found that particles travel 5–200 times further than previously thought. The smallest particles act like a cloud and can travel tens of metres and even float up to the ceiling and into office air conditioning systems.
Watch this disturbing high-speed camera video of someone sneezing, made by the research group of Prof Lydia Bourouiba at MIT:
The 2014 MIT research on coughs and sneezes, combined with ongoing research to support the fact that COVID-19 is airborne ( you can read this MedicalBrief article which clearly states 10 medical reasons supporting airborne transmission) should be enough to convince just about anyone that in addition to social distancing and hand sanitising, indoor air purification measures should be added to our standard arsenal of pandemic precautions for the workplace.
What can we do about airborne particles?
Adding air purification to indoor spaces where people gather - particularly workplaces, healthcare settings and schools - is a necessary addition to our arsenal against the war on COVID-19 and influenza because these units are specifically designed to trap and destroy airborne particles.
All of our VIRUSKILLER™ Air Purifiers kill 99.9999% of viruses in a single air pass, including Coronavirus*. Installing these units will both improve indoor air quality and stop the airborne transmission of infectious illnesses, making indoor spaces safer for customers, visitors, patients and staff.
Maintaining rigid hygiene protocols and pandemic protection measures are an excellent way to try and avoid both COVID-19 and the flu this winter, but they rely on EVERYONE doing their part. The major cause of the transmission of illness is other people because as soon as there is a break in the chain of protection, everyone is at risk.
Covid-fatigue is real, causing people to not wear their masks, wash their hands or maintain social distancing, and it's been identified as a major possible driver of a potential third wave of Covid-19 infections according to the director-general of the Department of Health. But implementing an air purification solution in your workplace can go a long way in reassuring colleagues that every possible precaution is being taken to ensure their wellbeing this winter.
Find out more about air quality in our consumer survey infographic, or why not download the VIRUSKILLER™ range brochure? You can also contact our team to find out more about how the VIRUSKILLER™ can service your environment.