While in-flight transmission of novel coronavirus among passengers is considered to be low, three studies have found instances where coronavirus transmission had probably taken place in-flight. The spread has probably become possible as mask wearing was not compulsory early in the pandemic. But thermal imaging, which has been in place since the beginning, has been found wanting.
Aerosol transmission
Experimental study finds how coronavirus can spread while speaking
Based on experiments and simulations, researchers have found that air emitted during plosive speech sounds — where a consonant (P, B, T, D, K and G) is produced by stopping the airflow using the lips, tongue tip or body followed by a sudden release of air — lead to significantly enhanced directed transport of the virus. When the speech contains a train of such puffs a continuous, turbulent, jet-like flow is formed and is capable of transporting air and droplets to over two metres in just 30 seconds.
Confusion reigns as CDC takes down guidance that confirmed aerosol transmission
A draft of the proposed changes to its recommendations, which was later withdrawn pending finalisation, the CDC confirmed that airborne particles can spread even by breathing, remain suspended in air and be inhaled and spread beyond six feet in certain enclosed settings.
CDC says revised guidance on coronavirus spread ‘posted in error’, removes it
On September 21, CDC removed the revised coronavirus spread guidance that acknowledged airborne transmission through aerosols, saying it was "posted in error". The revised guidance posted three days ago stated that particles carrying the virus can remain suspended in air and spread to distances beyond six feet and is the "main way" the virus spreads.
Finally, CDC acknowledges aerosol as the ‘main way’ of coronavirus spread
On September 18, CDC revised its guidelines to acknowledge that the “main way” the novel coronavirus (SARS-CoV-2) spreads is through aerosols. It also for the first time mentions that virus can spread through breathing, stay suspended in air and travel to distances beyond six feet.
A superspreader transmits coronavirus to 23 others in air-conditioned bus. So how safe will metro rail travel be?
A single person travelling in an air-conditioned bus along with 67 other passengers in Zhejiang province in eastern China on a 100-minute round trip spread the virus to 23 people. With India's Unlock 4 guidelines permitting metro rail services operation from September 7 outside the containment zones, how safe will metro rides be.
Viable coronaviruses collected from air more than six feet strengthens aerosol transmission
Researchers have been able to isolate virus from air samples collected 2 to 4.8 metres away from the patients. The viability of the virus present in air was proved by culturing the virus. The genome sequence of the virus isolated from air is identical to patient samples. Researchers had so far been able to collect … Continue reading Viable coronaviruses collected from air more than six feet strengthens aerosol transmission
Exhaled breath of COVID-19 patients found to contain novel coronavirus
The study found a few patients exhaled coronavirus into the air at an estimated rate of 1000-1,00,000 RNA copies/minute. Breath emission rate was the highest during the earlier stages of COVID-19. Virus emission was found to be a “sporadic event”. Not just talking, singing or shouting, as the World Health Organization indicated on July 9, … Continue reading Exhaled breath of COVID-19 patients found to contain novel coronavirus
WHO acknowledges airborne transmission of coronavirus in closed settings, and asymptomatic spread
The World Health Organization on July 9 acknowledged that novel coronavirus can be airborne in closed settings and spread from one person to another in such settings which are poorly ventilated and after prolonged exposure. It also acknowledged that people without symptoms can spread the virus. The World Health Organization on July 9 acknowledged that … Continue reading WHO acknowledges airborne transmission of coronavirus in closed settings, and asymptomatic spread
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