Beware! New Study Reveals That Covid-19 Virus Can Infect Cells In Eyes

The study highlighted importance of washing hands, as rubbing one's eyes should now be viewed as an entry point for infection, the researchers said.

New Delhi: A new study conducted by a team of researchers in the US has revealed direct evidence that the Covid-19 spreading virus, SARS-CoV-2 can infect the cells in the eyes. 

SARS-CoV-2 is thought to transmit and begin infection in the upper respiratory tract. However, the study's findings showed that SARS-CoV-2 can infect surface cells of the eye. 

The findings of the study conducted by the Mount Sinai Hospital showed that SARS-CoV-2 can infect surface cells of the eye. While aerosol transmission is thought to be the primary route of spread, viral particles have been detected in ocular fluid suggesting the eye may be a vulnerable point of viral entry. Because it is thought to transmit by the upper respiratory tract, the use of face masks has been recommended for the general public.

Published in the journal Cell Stem Cell, has an immediate impact on preventive measures to help mitigate the spread of Covid-19 and support new guidance for eye protection that can be instituted worldwide. It also highlights the importance of washing hands, as rubbing one's eyes should now be viewed as an entry point for infection, the researchers said.

The study was done on adult human eyes in an in vitro stem cell model. The donor cells were infected with SARS-CoV-2 and then analyzed through RNA sequencing. The sequences were then mapped to the human genome and compared to non-infected control cells from adult tissues. The expression of the exposed cell where then evaluated.

'Transcriptional analysis of ex vivo infected ocular surface cells and hESC-derived eye cultures revealed robust induction of NF- k B in infected cells as well as diminished type-I/III interferon signalling. Together these data suggest that the eye can be directly infected by SARS-CoV-2 and implicates limbus as a portal for viral entry,' it said in the study. 

The exposed cells revealed the presence of infection-associated proteins including ACE2, the virus receptor and TMPRSS2, an enzyme which allows viral entry. IFN-beta, a protein that has antiviral and antibacterial properties was also found to be suppressed from the exposure to the virus. In addition, the researchers found that ocular surface cells, particularly the limbus, were susceptible to infection, while the central cornea was less vulnerable.

"We hope this new data results in additional measures to protect the eyes. We also intend to use these models to test approaches to prevent ocular infections," said Timothy Blenkinsop, Assistant Professor, at Mount Sinai according to IANS.