KARACHI: The antiviral walk-through gates being installed all over the country are “toxic traps” and “provide a false sense of security”, infectious diseases experts said on Friday.

With the country struggling to deal with the Covid-19 pandemic despite an extended lockdown, the gates are being set up in various public spaces — in front of public offices, mosques, hospitals, vegetable markets and railway stations — all over the country as a ‘safety shield’ against the virus.

Talking to Dawn, Dr Shireen Khan, head of tuberculosis and chest diseases department at the Fatimah Jinnah Hospital in Quetta, said these gates are superficial.

“People need to remember that the virus inside your body does not die once you walk through these gates. These [walk-through gates] do not provide complete safety against the virus and there is no recommendation from the WHO in this regard,” said Dr Khan, who is looking after Covid-19 patients in Balochistan.

Such decisions involve huge investments and should be backed by scientific evidence, experts say, while stressing that public safety is paramount.

People must not forgo hand washing, social distancing if they walk through such gates

Dr Khan stressed that the people must not forgo the basic protocols — hand washing, sneezing etiquette, social distancing — if they walk through these gates.

A lot of people feel that these gates are safe “because in films they show people walk in and out of labs after being sprayed”. What they are talking about is biosafety level 4 (BSL-4) — the highest level of biosafety precautions, and is appropriate for work with agents that could easily be aerosol-transmitted within the laboratory and cause severe to fatal disease in humans for which there are no available vaccines or treatments.

In BSL-4 labs, personnel must pass through a chemical shower for decontamination, then a room for removing the positive-pressure suit, followed by a personal shower, according to safety guidelines.

“This is a latest joke being played on the public,” said Dr Shobha Luxmi, infectious disease specialist and assistant professor at the Dow University of Health Sciences (DUHS).

“This is a waste of money,” she said, sharing that someone offered to set up such a tunnel gate at the hospital and she refused the offer. “The virus won’t die. It needs 30 seconds to disintegrate.”

‘Only clothes are sanitized’

“Only clothes are sanitized, that too if a person walks through slowly,” said Dr Mukhtiar Zaman, the head of pulmonology at the Rehman Medical College Peshawar.

He said the basic rule is maintain good hygiene and maintaining social distance. The chemical will cause allergic reaction and breathing issues.

So does “spraying alcohol or chlorine all over your body kill the new coronavirus?”

On the WHO website, this question has been answered very specifically: “No. Spraying alcohol or chlorine all over your body will not kill viruses that have already entered your body. Spraying such substances can be harmful to clothes or mucous membranes (ie eyes, mouth). Be aware that both alcohol and chlorine can be useful to disinfect surfaces, but they need to be used under appropriate recommendations.”

When reached for comment, the Medical Microbiology and Infectious Diseases Society of Pakistan (MMIDSP) said: “Covid-19 virus primarily infects cells in air sacs of the lungs (alveolar macrophages) but is capable of infecting many different cell types and organs in the body. It resides and multiplies within the cells; mature virus exits the cell, finds its way into respiratory secretions and is coughed out and transmission continues.”

During the infectious phase, says MMIDSP president Dr Bushra Jamil of the Aga Khan University Hospital, only an effective antiviral agent can be expected to block multiplication and spread of the virus. Such an antiviral for SARS CoV-2 has not been found yet. If there is any part of the human body which should be decontaminated to block transmission, it is the hands, which brings us back to ‘hand washing’.

All experts agreed that the other important thing is use of mask by symptomatic individuals because virus is in secretions.

“Use of mask by symptomatic individual or asymptomatic infected individual can reduce transmission by blocking droplets. So combination of hand hygiene and universal use of masks (regular cloth mask would do) is effective,” the experts stressed.

Avoid use of bleach in spray form

Given that 70 per cent alcohol for disinfection is expensive, many people are opting for spray solution that contains chlorine (household bleach).

The experts stressed that use of bleach should be avoided in spray form. “Fumigation should never be used on people. It is meant for inanimate objects and surfaces. Also the chemical damages eyes, skin, throat and lungs,” the experts said.

A 2016 research paper Deliberate exposure of humans to chlorine — the aftermath of Ebola in West Africa by Shaheen Mehtar, Andre N. H. Bulabula, Haurace Nyandemoh and Steve Jambawai noted that “there was a statistically significant increase in the clinical symptoms of healthcare workers (HCW) when they were exposed multiple times to chlorine spray. The use of chlorine to disinfect personal protective equipment (PPE) while HCW are wearing it is not only without evidence, ineffectual but can be hazardous to health”.

“Secondly, the available PPE that was used by HCW did not protect them against the adverse effects of chlorine spray. This was because when chlorine is inhaled it converts to hydrochloric acid in the respiratory tract and causes severe clinical symptoms,” the paper went on to add.

The researchers strongly recommend that the spraying of humans with chlorine is banned forthwith; however, appropriate concentration of chlorine may be used for environmental disinfection when recommended by IPC teams.

“Should chlorine be indicated for disinfection, it should be applied as a wipe rather than a spray. Alternatives such as 70 per cent alcohol should be considered,” it added.

Published in Dawn, April 11th, 2020