The world is suffering from the pain and terror of coronavirus. Till now people were feeling hard to cope with the knowledge of new adaption to self-isolation, social distancing, washing hands repeatedly and sanitizing everything like an OCD patient, and lastly wearing a mask all the time.
On 29th of March, 2020 World Health Organization confirmed that Coronavirus is not airborne.
This confirmation gave people a sigh of relief that at least its not floating in the air and they can breathe freely. People somehow got confused about this statement that if it is not airborne then why are people asked to put on masks? and many other questions developed in mind about its transmission. Hence WHO took a step to clarify these questions. According to the assessed reports, the virus can float up to a radius of 1 meter and that is the reason people are asked to maintain social distancing. If an affected person sneezes or spits while talking, the virus can transmit, hence wearing a mask becomes necessary.
But the only relief people were having inside turns out to be gone now. On the 9th of July, the World Health Organization updated its reports about the transition of coronavirus saying that primary transition can occur through close contact with an infected person. But the airborne transition can take place in specific health care settings as well.
These twitter posts were an update about Modes of transmission of coronavirus which was implied for IPC (infection prevention and control recommendations).
Respiratory droplets from infected individuals can also land on objects or other surfaces. It is likely that people can also be infected with #COVID19 by touching these surfaces & touching their 👀, 👃 or 👄 before cleaning their 👐. https://t.co/WHHe4vuyF8— World Health Organization (WHO) (@WHO) July 9, 2020
She clearly states the possibility of coronavirus of remaining in the air in crowded indoor spaces with low ventilation and short-range aerosol transition can occur.
This update has come after 3 days after a group of two hundred and thirty-nine scientists from thirty-two countries publishes a statement named ‘It is Time to Address Airborne Transmission of COVID-19’ where the scientists appealed the relevant national and international bodies along with the medical community to recognize the potential of coronavirus’ airborne spread.
On the 7th of July the World Health Organisation’s technical lead on the pandemic, Dr. Maria said that “we have been talking about the possibility of airborne transmission or aerosol transmission as one of the modes of transmission.”
In the settings of crowded indoor like fitness classes, choir practice, and restaurants the possibility of aerosol transmission although combined with droplet transmission, has occurred according to the numerous recent studies by WHO. There is this slightest thought which passes by WHO is that even in these situations the virus can not be transmitted by the aerial route. It states that “the detailed investigations of these clusters suggest that droplet and fomite transmission could also explain human-to-human transmission within these clusters.” When an individual is in these crowded situations, transmission can occur through the primary mode as well – if an infected person sneezes, talks, or coughs. When the transmission occurs through an infected surface like elevator buttons, phones, switches, or doorknob that is referred to as fomite transmission, which can also be aa reason in such settings.
The aerosol transmission was no put concern earlier outside the areas which involve healthcare workers engaged in certain medical procedures. But now the current evidence claim that virus transmission through aerial route is possible outside the settings of medical facilities as well.
The need for this hour is urgent high-quality research for analyzing the relative importance of various transmission routes, what is the role of airborne transmission in the truancy of aerosol-generating procedures, requirement of virus dose for transmission to take place and most importantly the risk factor and settings of super-spreading events at the limit of pre-symptomatic and asymptomatic transmission.
The researches and studies which led to the conclusion:~
- Wuchang Fangcang Field hospital & Renmin Hospital (Wuhan)
One of the first studies about the same which was published in Nature was done here. The aerodynamic nature of the virus was investigated in this study by measuring its viral ribonucleic acid i.e. the RNA in aerosols. The study further discovered that the concentration of virus in aerosols was detected extremely low in ventilated patient rooms and isolation wards but it was very high in the toilet areas which was used by the patients. The study further stated that “Levels of airborne Sars-Cov-2 RNA in the most public areas was undetectable, except in two areas that were prone to crowding.” It also mentioned that “Although we have not established the infectivity of the virus detected in these hospital areas, we propose that Sars-Cov-2 may have the potential to be transmitted through aerosols.”
- US National Institute of Allergy and Infectious Disease
A correspondence was published in the New England Journal of Medicine in April by the researchers of NIAID where the stability of the virus on different surfaces and in aerosols was evaluated. The duration of the experiment was of about 3 hours and it was found that the virus remained in aerosols throughout the time being. The study further stated that “Our results indicate that aerosols and fomite transmission of Sars-Cov-2 is plausible since the virus can remain viable and infectious in aerosols for hours.”
But the World Health Organization expressed disagreement on this by saying that 3-hour activation of the virus in aerosol particles does not show a clinical setting where aerosol-generating procedures are being performed rather this was an “experimentally induced aerosol-generating procedure.”
- US Centers for Disease Control and Prevention (CDC)
CDC published a study named ‘High SARS-CoV-2 Attack Rate following Exposure at a Choir Practice‘ in May. the ‘super spreading events‘ were studied by the researchers and they found that thirty-two confirmed cases and twenty probable coronavirus cases occurred in 2.5 hours of choir practice which was attended by sixty people and one symptomatic index patient. After this 2 people died and 3 were hospitalized. The study reported that might be just the act of singing contributed to the transmission through the release of aerosols which got affected by the loudness of vocalization. It also stated that “Certain persons, known as super emitters, who release more aerosol particles during speech than do their peers, might have contributed to this and previously reported COVID-19 super spreading events.” During a speech, the loudness of vocalization is correlated to aerosol release. Super emitters have been hypothesized as contributors to super spreading events.
So from all this, we conclude that mask-wearing becomes a more crucial measure of protection than it was previously, everyone should avoid visiting crowded places as much as possible and if one has to visit a closed area proper ventilation availability should be on the prior checklist.