Dangerous new Covid-19 threat appears in aerosol form
WITH the massive spike in Covid-19 infections, the National Command Council must, as a matter of extreme urgency, study the report of the 239 scientists from 32 countries which graphically reveals a new emerging Covid-19 threat – namely aerosol infection in an open-air transmission mode.
It is clearly evident that a new wave of infections could be contamination by tiny droplets, or aerosols, present in the vicinity of dense human traffic, compared with larger droplets that are expelled when a sick person coughs or sneezes, or transmitted through contact with surfaces.
Masks can prevent infections, but aerosol infections can spread through our eyes, which suggests that a new strategy has to be urgently formulated.
Tiny aerosols are released into the atmosphere when a person without symptoms exhales, talks or sings.
A new limited lockdown under level 3 should consider instructions that citizens minimise time spent in an open-air environment and that institutions should be required to install air filters and ultraviolet lights that can kill airborne viruses.
Preventing airborne transmission of the virus should be our next front for the battle against Covid-19. It is possible that the current huge surge could be linked to a rapidly changing scenario involving aerosol as a deadly emerging factor.
Covid-19, like many viruses, is less than 100mm in size but expiratory droplets (from people who have coughed or sneezed) contain water, salts and other organic material, along with the virus.
The water content from the droplets evaporates, the microscopic matter becomes small and light enough to stay suspended in the air. Over time the concentration of the virus will build up, increasing the risk of infection, particularly if the air is stagnant.
Intervention by the health experts is urgently warranted to recognise and understand airborne transmission of Covid-19 and similar viruses, to minimise the build-up of virus-laden air in places typically containing high densities of people, as is evident in our major cities.
Reports exist of people who were infected, even though they had not shaken hands or stood close to one another.
Air-conditioned units are also a critical factor in the transmission chain.
Like cigarette smoke, aerosol particles spread around a person in a cloud, with the concentration being highest near the smoker and lower as one gets further away.
Research indicates that droplets could contain seven million virus particles per millilitre. A minute of high-pitched speech could generate more than 1 000 virus-containing droplets that could hang in the air for 8 to 10 minutes.
Crowded areas such as supermarkets, taxis and any highdensity institutions could be a risky environment and a possible breeding area.
Unless and until we as a nation exercise strict personal control, the chances of containing the virus, let alone defeating it, are diminished every day, as we blatantly and brazenly defy health regulations.
Covid-19 is a rapidly evolving enemy, whose venom continues to defy any medical assault – an elusive foe whose shadow now appears in an aerosol silhouette.