Preventing COVID-19 Spread: Face Mask or Face Shield?

Ghana’s social media space has in the last two months been awash with photos of face shields up for sale as protective gears in the fight against COVID-19.

Some of those who advertise them for sale claim them to be better alternatives to face masks.

Face masks, like face shields, are among many different personal protective equipment (PPE) that help to prevent the spread of some infections including COVID-19.

Other PPEs include goggles to protect the eyes, gowns and aprons to protect the skin, and gloves to protect the hand.

Face masks also protect the mouth and nose from catching infections while the face shield provides covering for the face, mouth, nose, and eyes from infections.

The face mask is typically three-layered made up of a melt-blown polymer, placed between non-woven fabric with an elastic band or strap to hold the ear or tie behind the head while face shield basically is any type of clear plastic film with an elastic strap to hold it to the face or the handles of eyeglasses to hold to the ear.

According to the World Health Organization (WHO), SARS-CoV2 virus, which causes COVID-19 is spread from person-to-person through contact with infected surfaces and through direct contact with respiratory droplets generated when an infected person coughs or sneezes.

Among other preventive etiquettes, the WHO has for months been emphasizing the need to wear masks to limit the spread of COVID-19 so its importance has not been in doubt.

“The use of masks is part of a comprehensive package of the prevention and control measures that can limit the spread of certain respiratory viral diseases, including COVID-19,” the WHO says.

But the advent and craze about face shields prompted further studies into its effectiveness in terms of fighting COVID-19.

The WHO, in a new guideline reviewed by Fact-checkghana, indicated that although face shields are protective equipment, they are inferior to face masks because they do not offer as much protection against droplet transmission.

“In the context of non-medical mask shortage, face shields may be considered as an alternative noting that they are inferior to mask with respect to prevention of droplet transmission,” the published WHO document notes.

Scientists explain that to the extent that some research has proven that SARS-CoV2, the virus that causes COVID-19 could be airborne it is advised that face shields be worn over face masks.

While face shields provide covering for the mouth, eye and nose, they allow for some amount of unfiltered air and possible SARS-CoV2-bearing air to reach the eyes, mouth or nose.

For that reason, the WHO advises, “If face shields are to be used, ensure proper design to cover the sides of the face and below the chin.”

Nana Kofi Quakyi, an adjunct Assistant Professor in the Department of Health Policy and Management at New York University’s School of Global Public Health also holds that same view.

He says claiming that face shields are more important or a perfect alternative to face masks is akin to selling false security.

“A face shield like this can be a complement to a face mask, but it is not a replacement… Don’t market these shields as substitutes for facemasks. All you’d be selling is false security.”

The Head of Surveillance at the Ghana Health Service, Dr Asiedu Bekoe, at a press briefing in July 2020 also emphasized the point that face shields alone do not offer as much protection from COVID-19 as the face mask does.

“For the purpose of addressing the challenge of infection, the first port of call is the face mask… We want to implore all Ghanaians that let’s use the face mask because that is the purest way that you can prevent yourself from getting infection.”

“If you wear the face shield, then it must be on top of a face mask but it should not be an alternative to the use of the face mask and I want to assure all Ghanaians that it is not for convenient that we are replacing face shields with face masks but it is for the purpose of preventing infections,” he said.

He however gave an exception that face shields can be worn alone by persons communicating with people who are hearing-impaired and may rely on lip-reading to communicate.