Face masks are being used as the first line of defence of individuals in both China and beyond against the novel coronavirus (2019-nCoV). However, are face masks really enough?
Face masks are an effective means of reducing the spread of respiratory infections. They limit the release of infection causing droplets released through sneezing and coughing in individuals already infected, as well as reducing the inhalation of such droplets in those not infected.
However, a recent correspondence in The Lancet has potentially revealed initial evidence that the virus is capable of infection via the ocular surface. Such a development would render the commonly used face masks to be only partially effective. Given the elongated incubation period reported among some infected with the virus, this could significantly hinder quarantine efforts.
The correspondence letter notes “on Jan 22, Guangfa Wang, a member of the national expert panel on pneumonia, reported that he was infected by 2019-nCoV during the inspection in Wuhan. He wore an N95 mask but did not wear anything to protect his eyes. Several days before the onset of pneumonia, Wang complained of redness of the eyes. Unprotected exposure of the eyes to 2019-nCoV in the Wuhan Fever Clinic might have allowed the virus to infect the body.”
An ocular surface mechanism of infection is not unprecedented. Some studies have indicated such a mechanism in several strains of the flu, indicating that viral infection via this pathway may be the case in that of novel coronavirus. The correspondence letter notes that this has been the case in some of the most closely related viruses to the coronavirus “Severe acute respiratory syndrome coronavirus (SARS-CoV) is predominantly transmitted through direct or indirect contact with mucous membranes in the eyes, mouth, or nose,” indicating this may once again be the case in the 2019-20 outbreak.
They go on to say that “Huang and colleagues should have analysed conjunctival scrapings from both confirmed and suspected 2019-nCoV cases during the onset of symptoms. The respiratory tract is probably not the only transmission route for 2019-nCoV, and all ophthalmologists examining suspected cases should wear protective eyewear.” As this is not the case as of the time of writing, the ocular route of infection — if it is indeed occurring — leaves a gaping hole in the current defences against the disease.
There have been 43,106 cases reported as of February 11th, with 1,018 deaths. Of the 43,106 cases reported, 4,045 have recovered. Of the 38,043 individuals currently infected with coronavirus, 30,698 are reported to be in mild condition. The remaining 7,345 are in critical condition.
India has reported three cases of the novel coronavirus, all of them in the state of Kerala. In fortunate news, one of the infected individuals – a student from Wuhan University in the Hubei province capital where the outbreak originated – has tested negative for coronavirus in a fresh test at the National Institute of Virology. “The blood test result of the first patient from Thrissur from the National Institute of Virology (NIV) testing centre at Alappuzha shows a negative result,” commented an official.
Responses from the Chinese government have indicated they believe the situation to be under control. The senior medical advisor to the Government of China has said that the outbreak of the virus could be over as soon as April and projected that it would reach its peak this month. Despite optimistic predictions, disease cases continue to rise, with ever more cases being reported and an ever present potential for international spread placing the disease on the verge of a pandemic level threat at all times.
The potential for spread through the ocular surface, combined with the as-of-yet unruled out potential of airborne transmission could mean that the capability of effectively isolating the disease when so many cases have already been confirmed may be all but impossible.