[By Sopuruchi Onwuka]
The uptick in air transportation and widespread use of face shields as protection against airborne novel coronavirus pathogens might be the major cause for resurgence of infections across the world.
The new insights into the mode of viral spread flow from the initial test of the billion pound sterling supercomputer, Fugaku, developed by the Japanese government to study the characteristics of the novel coronavirus which has held the world hostage since January this year.
International infection causes surveyed by The Oracle Today suggest that cohabiting air pressurized aircraft cabins with infected persons could increase the risk of multiple infections in short flight duration periods.
The fears of inflight infection surge was amplified in the reported case of the weekend’s London-Vietnam flight during which one coronavirus vector infected over 15 people during the trip.
According to the report by the American Center for Disease Control (CDC) the single plane passenger infected 15 people with the virus which causes the dreaded Covid-19 that has been responsible for the prevailing global pandemic that killed hundreds of thousand people and sickened over a million people across the globe.
In a NBC News review by The Oracle Today in Lagos, the American CDC stated in a study published Friday that a single passenger was the source of a coronavirus infection outbreak aboard a flight from London to Hanoi, Vietnam.
The 27-year-old woman from Vietnam was said to had suffered sore throat and a cough before the flight, and later identified as the vector that transmitted the deadly virus to 12 passengers in business class, two in economy and a crew member in the flight under review.
Although the flight was made on March 1, it amply highlights the infection risk associated with flying with an infected passenger.
Inflight infection risks are behind the stringent measures taken by the civil aviation industry requiring all passengers to strictly comply with all infection prevention protocols while embarking on an air trip.
In Nigeria, passengers are required to carry coronavirus test certificate that declared the passengers free of the infection in addition to onspot checks for high temperature, wearing of face masks and other precautionary measures deployed at the airports.
The study of the London-Vietnam flight showed that “the risk for on-board transmission of SARS-CoV-2 during long flights is real and has the potential to cause Covid-19 clusters of substantial size,” the authors wrote.
“Our findings call for tightened screening and infection prevention measures by public health authorities, regulators, and the airline industry.”
Health officials said that at the time of Flight VN54’s arrival, passengers and crew members were not required to wear masks in airplanes or at airports. All passengers from Covid-19-infected areas, including the U.K., were screened by thermal imaging upon arrival, but the study does not say whether the woman was flagged for symptoms.
Since March, the CDC has found that nearly 11,000 people were exposed to the coronavirus on flights, another report by the Washington Post contained.
In its public health guidance, the CDC says that viruses are not easily spread on planes because of their air filtration systems but that sitting within 6 feet of other people and touching frequently used surfaces on long-haul flights can increase the risk of contracting Covid-19, according to one of the reports.
The authors of the Vietnam flight study declared: “As long as Covid-19 presents a global pandemic threat in the absence of a good point-of-care-test, better on-board infection prevention measures and arrival screening procedures are needed to make flying safe.”
The recommended mandatory face coverings, routine hand-washing and testing protocols, and quarantine policies for arriving passengers from countries of high risk.
But a separate report by The Guardian of London quotes Japanese the supercomputer as saying that face masks which have become vogue in Nigeria may have to be made compulsory as face shields have proved ineffective at trapping aerosols.
According to the report, plastic face shields are almost totally ineffective at trapping respiratory aerosols, casting doubt on their effectiveness in preventing the spread of coronavirus.
Government-backed research institute in the western city of Kobe, Riken, stated that about half of larger droplets measuring 50 micrometres found their way into the air.
A simulation using Fugaku, the world’s fastest supercomputer, found that almost 100% of airborne droplets of less than 5.0 micrometres in size escaped through plastic visors of the kind often used by people working in service industries.
A micrometer is one millionth of a metre.
Team leader at Riken’s centre for computational science, Makoto Tsubokura, said the simulation combined air flow with the reproduction of tens of thousand droplets of different sizes, from under 1 micrometre to several hundred micrometres.
He cautioned against wearing face visors as an alternative to masks.
“Judging from the results of the simulation, unfortunately the effectiveness of face guards in preventing droplets from spreading from an infected person’s mouth is limited compared with masks,” Tsubokura told the Guardian.
“This is especially true for small droplets of less than 20 micrometres,” he said, adding that all of the much smaller aerosol particles were found to escape through the gap between the face and the face shield. “At the same time, it somehow works for the droplets larger than 50 micrometres.”
Tsubokura suggested that people who are advised not to wear masks, such as those with underlying respiratory problems and small children, could wear face shields instead, but only when outdoors or in indoor settings that are properly ventilated.
Fugaku, which can perform more than 415 quadrillion computations a second, recently found that face masks made from non-woven fabric are more effective at blocking the spread of Covid-19 via airborne droplets than those made of cotton and polyester
The billion pound sterling supercomputer has also run simulations on how respiratory droplets spread in partitioned office spaces and on packed trains when the carriage windows are open.
Although it will not be fully operational until next year, experts are hoping it will help identify treatments for Covid-19 from about 2,000 existing drugs, including those that have yet to reach the clinical trial stage.
Japanese authorities have throughout the pandemic outlined that aerosol transmission and ventilation for critical factors in their public health advice.
The report noted that use of face shields is becoming a common sight in sectors that emphasize contact with the public, such as shops and beauty salons as some countries open up their economies.