Barber ( 2020 ) also quotes Julia Marcus , an epidemiologist at Harvard Medical School , as observing , “ There are bizarre policies that haven ’ t changed or adapted . It ’ s one thing for an individual to decide to stop bleaching their groceries . It ’ s much more difficult to steer the ship of an institution as the science evolves , with different levels of decision-making and different levels of health literacy and risk tolerance .” Marcus is quoted further as remarking on the Morris , et al . study : “ They couched it appropriately . But even with those caveats , it spun into a lot of obsessive behaviors . There ’ s such a high level of tension in our lives and decision-making right now . We all need to feel some ease . For me , the question is , where are the low-risk areas where we can ease off the gas now that we know more about how transmission happens — which is overwhelmingly from being together in indoor environments ? It ’ s not from a book that somebody sneezed on and brought to the library a week ago .”
Lewis ( 2021 ) observes that part of the problem is that “ specialists can ’ t rule out the possibility of fomite transmission , and the guidance from many health agencies about how to deal with surfaces has been unclear as the science has changed … the CDC directs people to a comprehensive list of agents that kill SARS-C0V-2 and says , ‘ Frequent disinfection of surfaces and objects touched by multiple people is important .’ Experts say that it makes sense to recommend handwashing , but some researchers are pushing back against the focus on surfaces . In December , engineer Linsey Marr at Virginia Tech in Blacksburg co-wrote an opinion article for The Washington Post imploring people to ease up on cleaning efforts . ‘ It ’ s become clear that transmission by inhalation of aerosols — the microscopic droplets — is an important if not dominant mode of transmission ,’ says Marr , who studies airborne disease transmission . Excessive attention on making surfaces pristine takes up limited time and resources that would be better spent on ventilation or the decontamination of the air that people breathe , she says .”
As we have seen , the focus on fomites rather than aerosols emerged at the very beginning of the SARS-CoV-2 outbreak and stemmed from common knowledge about other pathogens that are found in bioburden on surfaces and objects . As Lewis ( 2021 ) notes , “ So , as soon as people started falling ill from the coronavirus ,
A member of the research team swabs the hospital floor to help determine where SARS-CoV-2 is , and isn ’ t . Courtesy of UC San Diego Health Sciences
Chasing SARS-CoV-2
Watching what was happening around the world in early 2020 , University of California San Diego School of Medicine researchers knew their region would likely soon be hit with a wave of patients with COVID-19 , the infection caused by the coronavirus SARS-CoV-2 . They wondered how the virus persists on surfaces , particularly in hospitals , and they knew they had only a small window of time to get started if they wanted to capture a snapshot of the “ before ” situation -- before patients with the infection were admitted .
After a call late one Sunday night , a team assembled in the hospital lobby the next day , ready to swab .
In the resulting study , described June 8 , 2021 in Microbiome , researchers swabbed patient room surfaces before , during and after occupancy , and repeatedly collected samples from the skin , noses and stool of COVID-19 patients and their healthcare workers over time . In total , they tested 972 hospital-associated samples for traces of SARS-CoV-2 over two months .
“ Although it feels like we ’ ve been living with this virus for a long time , the study of the interactions between SARS-CoV-2 and other microbes is still new , and we still have a lot of questions ,” said co-senior author Sarah Allard , PhD , assistant project scientist at UC San Diego School of Medicine and Scripps Institution of Oceanography . “ The more we know about how a virus interacts with its environment , the better we can understand how it ’ s transmitted and how we might best disrupt transmission to prevent and treat the disease .”
Their findings : The virus , or at least its genetic signature , abounds . The team detected the virus on the floors next to the beds of patients with COVID-19 ( 39 percent of samples tested ), floors outside patient rooms ( 29 percent ) and surfaces inside the rooms ( 16 percent ). SARS-CoV-2 detection tended to be highest during the first five days after a patient ’ s onset of symptoms .
The researchers are quick to point out that just because they can detect the virus ’ unique genetic signatures on a surface , it doesn ’ t mean the virus is able to infect people . Since they started the study , it has been well documented that SARS-CoV-2 spreads primarily through close human interactions , while surface transmission is likely very rare . What ’ s more , none of the healthcare workers actively caring for patients in the study tested positive for the virus . The study focused on one hospital ,
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