Since the outbreak of the deadly coronavirus across the world, there have been lot of misconceptions and misinformation about the Virus. Famous among the argument is whether Covid-19 is airborne or not. TheICIR chronicles the available facts and evidence about the novel Coronavirus.
ACCORDING to the International Journal of Infectious Diseases (IJID), Coronaviruses (CoVs), a large family of single-stranded RNA viruses, can infect animals and also humans, causing respiratory, gastrointestinal, hepatic, and neurologic diseases, CoVs are further divided into four genera: alpha-coronavirus, beta- coronavirus, gamma-coronavirus and delta-coronavirus.
To date, there are six human coronaviruses (HCoVs) being identified, including the alpha-CoVs HCoVs-NL63 and HCoVs-229E and the beta-CoVs HCoVs-OC43, HCoVs-HKU1, severe acute respiratory syndrome-CoV (SARS-CoV), and Middle East respiratory syndrome-CoV (MERS-CoV).
New coronaviruses appear to emerge periodically in humans, mainly due to the high prevalence and wide distribution of coronaviruses, the large genetic diversity and frequent recombination of their genomes, and the increasing of the human-animal interface activities. The Covid-19 is the currently ravaging disease with over one million cases world-wide.
Keywords: Severe Acute Respiratory Syndrome (SARS), Coronavirus (CoV), Middle East respiratory syndrome (MERS), Personal Protective Equipment (PPE)
History of Covid-19
In late December 2019, a number of local health authorities reported clusters of patients with pneumonia of unknown cause, which were epidemiologically linked to a seafood market in Wuhan, Hubei Province, China.
The pathogen, a novel coronavirus (SARS-CoV-2), was identified by local hospitals using a surveillance mechanism for “pneumonia of unknown etiology” that was established in the wake of the 2003 SARS outbreak with the aim of allowing timely identification of novel pathogens.
Since December 2019, multiple cases occurring un-explainable pneumonia were successively reported in some hospitals in Wuhan city with a history of exposure to a large seafood market in Wuhan city, Hubei province, China. It has been confirmed to be an acute respiratory infection caused by a novel coronavirus. So far, this disease has rapidly spread from Wuhan to China’s other areas, and 66 countries. And then, clustered cases and confirmed cases without a history of travel to Wuhan emerged as the s disease started to advance.
To help create awareness and tackle its spread, the World Health Organization (WHO) on 12 January 2020 named the virus, it was given the name-tag, ‘Covid-19’.
In the following month, the 2019-nCoV was reorted to have quickly spread inside and outside of Hubei Province and even other countries. Another issue that rocked the global community, was the sharp increase of the case number which caused widespread panic among the people.
On 30 January 2020, the World Health Organization (WHO) declared that CoVID-19 is a “public-health emergency of international concern” . The pandemic is escalating rapidly. TheICIR searched the associated literature in CoVID-19 to summarize the epidemiology, clinical characteristics, diagnosis and treatments and preventions of the infection of SARS-CoV-2.
As the time of filing this report, no specific approved cure for the pandemic have globally agreed upon as over 65 thousand deaths have been recorded world wide. According to TheICIR Covid-19 dash board, as at press time, recorded over 222 thousand persons with more than 1 million cases globally.
According to Neeltje van Doremalen, Dylan H. Morris, et al’s conclusion published in New England Journal of Medicine tiltled “Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1″ published in the midst of the pandemic, on March 17th, 2020, the scientists who analysed the aerosol and surface stability of SARS-CoV-2, compared it with SARS-CoV-1 and postulated that the longest viability of both viruses was on stainless steel and plastic as the estimated median half-life of SARS-CoV-2 was approximately 5.6 hours on stainless steel and 6.8 hours on plastic. This was reached after an intensive evaluation of the stability of SARS-CoV-2 and SARS-CoV-1 in aerosols and on various surfaces and their decay rates were also estimated using a Bayesian regression model.
The data for the experiment was performed on 10 experimental conditions involving two viruses (SARS-CoV-2 and SARS-CoV-1) in five environmental conditions (aerosols, plastic, stainless steel, copper, and cardboard). All experimental measurements are reported as means across three replicates.
At the end of the experiment, the scientists concluded that Covid-19 is not an airborne virus. But it can be contracted through contact with infected surfaces of plastic and stainless steel.
On the covid-19 contracting mechanism, another contradictory argument postulated that Covid-19 can be transmitted through air (airborne).
According to the National Academy of Sciences (NAS) in a letter written to the Kelvin Droegemeier, head of the White House Office of Science and Technology Policy, posited that that the novel coronavirus can spread through the air as not just via the large droplets emitted in a cough or sneeze.
Despite the inconclusiveness of current studies “the results of available studies are consistent with aerosolization of virus from normal breathing,” Harvey Fineberg, who heads a standing committee on Emerging Infectious Diseases and 21st Century Health Threats, wrote.
The NAS panel raised concerns that personal protective equipment (PPE) could itself be a source of airborne contamination.
“A study of SARS-CoV-2 raises concerns about transmission via aerosols generated from droplet contaminated surfaces. Liu, et. al. collected 35 aerosol samples in two hospitals and public areas in Wuhan. From samples collected in patient care areas the highest concentration of virus was found in toilet facilities (19 copies m-3), and in medical staff areas the highest concentrations were identified in personal protective equipment (PPE) removal rooms (18-42 copies m-3). By comparison, in all but two crowded sites, the concentrations of virus found in public areas was below 3 copies m-3. The authors
conclude that a direct source of SARS-CoV-2 may be a virus-laden aerosol resuspended by the doffing of PPE, the cleaning of floors, or the movement of staff. It may be difficult to re-suspend particles of a respirable size.
However, fomites could be transmitted to hands, mouth, nose or eyes without requiring direct respiration into the lungs”.
This stance by Harvey Fineberg can be associated with the result of the researchers at Wuhan University in China led by Yuan Liu found that the novel coronavirus can be re-suspended in the air when healthcare workers remove their personal protective equipment (PPE), clean the floors, and move through infected areas.
Before these report, the U.S. Centers for Disease Control (CDC) and Prevention and other health agencies have insisted the primary route of transmission for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is through the larger respiratory droplets, up to 1 millimeter across, that people expel when they cough and sneeze. Gravity grounds these droplets within 1 or 2 meters, although they deposit the virus on surfaces, from which people can pick it up and infect themselves by touching their mouth, nose, or eyes. But if the coronavirus can be suspended in the ultrafine mist that we produce when we exhale, protection becomes more difficult, strengthening the argument that all people should wear masks in public to reduce unwitting transmission of the virus from asymptomatic carriers.
With the contrasting stances, the transmission of SARS-CoV-2 (Covid-19) through human respiratory droplets and contact with infected persons is clear, the aerosol transmission (airborne) of SARS-CoV-2 has been studied.
While efforts continue to ascertain the globally agreed nature of the Coronavirus and a cure for it, the checks and findings by The ICIR has revealed that two positions are clear, the Covid-19 is a respiratory disease, the Covid-19 can also be contracted through surface droppings and contact with infected persons. So, the Covid-19 can be said to be airborne under special conditions.
Findings also show that against the misconception that Covid-19 can be contracted by merely breathing in an infected area, such as not been established as a verifiable or globally accepted claim. The best we have is close metres to an infected person but not by generally breathing in air.