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Scientists Warn Coronavirus Can Enter The Body Through The Eyes


Scientists have claimed the coronavirus can enter the body through the eyes after finding they contain a protein employed by the infection to bind to cells.

The coronavirus - scientifically called SARS-CoV-2 - latches onto ACE-2 receptors, referred to as the 'gateway' into cells inside body. 

These receptors are found within the tract and therefore the lungs, which is where the virus first infiltrates cells, also as other organs.

A team led by Johns Hopkins University School of drugs have now found the eyes produce ACE-2, making them a target for the virus.

It means if droplets from an infected person's sneeze or cough were to land on the surface of the attention , the virus could begin infiltrating cells there.

It may explain why some patients have suffered conjunctivitis - an inflammation of the attention which causes it to become red and infected.

Not only could the virus enter the body through the eyes, but tears may function a selection of infection, scientists said. 

The team was led by Lingli Zhou of the Department of Ophthalmology, Johns Hopkins University School of drugs , Baltimore.

They analysed ten human post-mortem eyes from people that didn't die of COVID-19 for the expression of ACE2 (angiotensin-converting enzyme 2).

ACE-2 is known to be the entry point for the virus. Its spiky surface binds to the receptors and, from there, infects the cell and replicates. 
It's suggested that somebody with more ACE-2 receptors could also be more vulnerable to an outsized viral load - first infectious dose of an epidemic - entering their bloodstream.

The team also searched for TMPRSS2, an enzyme that helps viral entry following binding of the viral spike protein to ACE2. 

ACE2 and TMPRSS2 must both be present within the same cell for the virus to effectively replicate.

All eye specimens expressed ACE-2 within the tissue that lines the within of the eyelids, called conjunctiva, the clear outer layer of the attention , called the cornea, and therefore the limbus, which is that the border between the cornea and therefore the white of the attention .

TMPRSS2 was also expressed, consistent with the pre-print paper on MedRxiv yet to be reviewed by other scientists. 

Dr Zhou and colleagues wrote: 'Together, these results indicate that ocular surface cells including conjunctiva are vulnerable to infection by SARS-CoV-2, and will therefore function a portal of entry also as a reservoir for person-to-person transmission of this virus.' 

The research was triggered by 'extensive speculation' that eye surfaces are a possible site of virus entry. 

Although the virus primarily spreads through droplets of saliva or discharge from the nose from an infected person lands on the insides of another person's nose or mouth, scientists have said it's entirely possible it could enter through the attention .

Reports have suggested that COVID-19 may cause conjunctivitis, which was a symbol in around 30 per cent of patients in one study.

The researchers explained this might be as a results of the virus travelling from the tract to the eyes - a secondary complication often linked with an epidemic .

But it could even be an immediate results of the virus attacking the attention cells within the first place by binding to ACE-2 receptors. 

Dr Zhou noted that viral particles are often found in tears that 'could end in transmission to other individuals'. 

'Infection of ocular surface cells could lead on to the attention as being a crucial carrier, with ocular virus shedding constituting a big mechanism for infection of other individuals,' they wrote.

'This highlights the importance of safety practices including face masks and ocular contact precautions in preventing the spread of COVID-19 disease.' 

It was not specified if the overall population would benefit in the least from eye protection, or if the teachers meant doctors specifically. 

Medics on the pandemic frontline are alleged to wear goggles or face visors so as to guard their eyes. 

Doctors first warned the killer coronavirus might be spread through the eyes in January, when the epicentre was in Wuhan, China, and had reached only a couple of other countries.

Just 26 patients have died within the outbreak in China when doctor Wang Guangfa said he thought he had contracted the SARS-like infection because he wasn't wearing protective goggles. 

Several days before the onset of pneumonia, Dr Wang - a Peking University respiratory specialist - complained of redness of the eyes. 

Paul Kellam, professor of virus genomics at Imperial College London, told MailOnline at the time it had been 'absolutely possible'.

'If you've got droplets sneezed at you, they're going to wash from your eye to your nose,' he told MailOnline. 'Your eye connects to your nose through the lachrymal duct . 

'If you suffer from allergies and if your eyes run, so will your nose. Or if you set medication in your eyes, you’ll taste at the rear of your throat.

'It isn’t unusual for flu and other viruses to be transmitted this manner . you'll also get respiratory infections through the attention .' 

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