A brand new research by UC Davis researchers confirms the low probability that SARS-CoV-2 contamination on hospital surfaces is infectious. The research, revealed June 24 in PLOS ONE, is the unique report on recovering near-complete SARS-CoV-2 genome sequences immediately from floor swabs.
“Our crew was the primary to show that SARS-CoV-2 virus sequences could possibly be recognized from environmental swabs collected from hospital surfaces,” mentioned Angela Haczku, a respiratory immunologist and senior writer on the research.
Altering cleansing and ICU protocols linked to decrease SARS-CoV-2 contamination
In April 2020, a COVID-19 outbreak amongst hospital employees led an interdisciplinary crew of UC Davis researchers to research if there was virus contamination of incessantly used surfaces in affected person serving ICU and employees assembly areas on the UC Davis Medical Heart. At the moment the function of fomites (surfaces) in spreading the illness was extremely debated. They collected a number of samples throughout the first (April 2020) and the second (August 2020) waves of COVID-19 from surfaces and HVAC filters within the hospital.
The researchers analyzed the floor swabs for SARS-CoV-2 RNA and infectivity and assessed the suitability of the RNA for sequencing.
Regardless of a major enhance within the variety of hospital sufferers with COVID-19 throughout the second surge, the crew discovered that solely 2% of swabs examined optimistic in August, in comparison with 11% of samples collected in April.
“The discount within the virus contamination was doubtless as a result of improved ICU affected person administration and cleansing protocols,” Haczku mentioned. Haczku is a professor of medication, director on the UC Davis Lung Heart and affiliate dean for translational analysis on the UC Davis Faculty of Drugs.
Genome sequence of coronavirus discovered on surfaces
The research demonstrated that by genome sequencing, SARS-CoV-2 could possibly be detected even from samples that in any other case examined destructive (undetectable) by generally used PCR exams. The outcomes additionally confirmed that the SARS-CoV-2 RNA picked up from a floor, though containing near- intact genomic sequence, was not infectious. This discovering helps the speculation that contaminated surfaces is probably not a serious means for spreading COVID-19 illness.
“For the primary time, to our information, we had been capable of decide the viral genome sequence from floor swab samples obtained in a hospital surroundings,” mentioned David Coil, mission scientist on the UC Davis Genome Heart and the primary writer on the research. “We discovered SARS-CoV-2 in samples that had been examined destructive by RT-PCR, suggesting that the sequencing expertise is superior for virus detection in environmental samples.”
In keeping with Coil, the genome sequencing carried out on the hospital floor swab samples is essential. By getting correct viral genomic sequences, the researchers might monitor the supply and work out how an an infection strikes.
“Our knowledge indicated that the sequences decided for the viral RNA from surfaces had been similar to those derived from the sufferers hospitalized within the ICU on the time of pattern assortment. The flexibility to determine viral genome sequences from environmental samples might have excessive public well being significance in outbreak surveillance and monitoring the unfold of latest viral variants,” Haczku mentioned.
This research was funded by a UC Davis CRAFT Award and The Chester Robbins Endowment.
UC Davis co-authors are Timothy Albertson, Christian Sandrock, Daniel G Tompkins, Maya Juarez, Brandt Robinson, Shefali Banerjee, Greg Brennan, Satya Dandekar, Stefan Rothenburg , Ana Stoian, A.J. Campbell, Ivy Jose, Samuel L. Díaz-Muñoz, Stuart H. Cohen, Jonathan A. Eisen, Tracey Goldstein and Alexandre Tremeau-Bravard.