Following the city district government’s March 21 notification regarding “environmental disinfection and decontamination,” in order to prevent Covid-19 from spreading, Lahore saw a number of sanitisation walkthrough cabins that were installed at the entrances and exits of some public office buildings as well as places and localities identified as ‘hotspots’ for the virus. The cabins, popularly called ‘disinfection tunnels,’ spray those passing through them with a disinfectant. Of late, however, their utility is increasingly being questioned.

Primarily, the disinfectant is the problem. It contains sodium hypochlorite solution. Some experts are of the opinion that the spray can hurt eyes and enter one’s nostrils and mouth. The disinfectants are meant for surfaces, not human bodies, they say.

Interestingly, neither the Coronavirus Expert Advisory Group (CEAG), constituted by the Punjab government, nor the Drug Regulatory Authority of Pakistan (DRAP) have issued any standard operating procedures (SOPs) in this regard. The absence of an official policy, outlined by the federal/provincial or district government, is a cause for serious concern.

According to Dr Naseem Akhtar, the head of Infectious Diseases, and the focal person on Covid-19 at Pakistan Institute of Medical Sciences (PIMS), no national or international organisation working on containing the pandemic has recommended this method of disinfection. “Chlorine spray may sterilise only the surfaces, it won’t sanitise the human body,” she tells TNS. “And if you use a higher concentration [of chlorine], your body may catch harmful infections.”

Dr Shahid Malik, professor of Public Health and Community Medicine and general secretary of Pakistan Medical Association (PMA), sees the disinfection tunnels as “a money-making exercise. Those at the helm of affairs are making big bucks in cahoots with some private companies.”

He insists that no recommendations have been given by the government advisory panel on Covid-19 or the DRAP in this regard.

By design

Technically speaking, the disinfection tunnels are user-friendly and portable walkthrough corridors that can be customised. They are generally between 10 and 20 feet in length, and 6-10 feet in width and height. They are made of panaflex, fibreglass or cladding sheets. Their features include a frame with lighting, running pipes both on the ceiling and on the sides, an air pump, a pressure pump, and a tank. The spray solution is made with 6,000 litres of water, 30 grams of chlorine and 2.1 litres of methanol.

Disinfection tunnels cost somewhere between Rs 50,000 and Rs 300,000, depending on the quality of the materials used. Also, they may be automatic — i.e. those fitted with motion sensors — or manual, in which case the visitors passing through them need to operate the spray themselves. It is the latter type of tunnels that is most commonly seen in Lahore. The one installed on The Mall has an automatic sensor that detects movement as people pass through it, and sprays chlorine water on them. A tank filled with chlorine is placed next to the tunnel.

More than 20 disinfection tunnels have been set up in the city, by the Metropolitan Corporation of Lahore (MCL), in cooperation with Lahore Development Authority (LDA) and the Water and Sanitation Agency (WASA).

Interestingly, neither the Coronavirus Expert Advisory Group (CEAG), constituted by the Punjab government, nor the DRAP have issued any Standard Operating Procedures (SOPs) in this regard.

The lay people seem to trust them to kill the virus. Fahad Zameer, a shopper at a grocery store, says that globally, disinfection tunnels have yielded positive results: “They are a common practice now. China and other countries have installed them and obtained great results.”

Zubair Chattha, a private installer, says that “small amounts of chlorine, mixed with water, and sprayed on your clothes/body can’t be harmful. If it were a health hazard, the authorities would not have allowed them to be set up.”

False security

Some experts say that the disinfection tunnels give the users a “false sense of security”. Those who walk through them may be inclined to go without feeling the need to wash their hands or practice social distancing as they should.

Another consideration is the sanitisation time which, in the case of these tunnels, is not monitored. A few seconds in the spray aren’t enough to inactivate the virus.

Dr Shoaib Niazi, the focal person on Covid-19 at Mayo Hospital and senior vice president of Young Doctors’ Association-Punjab, says: “They are meant to give the people a false sense of satisfaction. “Such things are popping up because the government did not engage the right people in the right jobs.”

The World Health Organization (WHO) clearly states that spraying alcohol or chlorine over your body will not kill the viruses that have entered your body. In fact, these substances can harm your mucous membranes (i.e. eyes, mouth). They can disinfect surfaces, but they must be used with appropriate precautions.

China was the first country to use the disinfection tunnels in Wuhan and other cities badly hit by the virus. Later, Malaysia, Indonesia, Turkey, India and some other countries picked up the idea. Soon afterwards, question were raised about their efficacy and safety. Early this month, such tunnels across Mexico City were removed. Most recently, Morocco banned both the use and marketing of these tunnels in the country over concerns for exposure to hazardous products.

A senior official at the National Institute of Health (NIC), Field Epidemiology and Disease Surveillance Division, says that China and other countries are using disinfection sprays to sanitise their streets, roads and buildings. “The standard staying time inside the so-called disinfection tunnels is between three and eight seconds. A simple hand wash takes you 20 seconds. So, technically speaking, sterilisation is not possible at these walkthroughs.

“If a person is completely drenched, while a street is being washed with disinfectant, that might be different. But in that case, harmful effects on human body cannot be ruled out,” he adds.

Recently, the World Bank sanctioned a Rs 33 billion loan for Pakistan, under its Pandemic Response Effectiveness Project (PREP) which lays down strategies on healthcare. It did not suggest setting up the sanitisation walkthrough cabins. The Ministry of National Health Services Regulations and Coordination issued guidelines on fumigation or fogging of antimicrobial agents (chlorine etc), but did not recommend routine procedures in a healthcare environment.

Dr Izhar Ahmed Chaudhry, an executive member of the Pakistan Medical Association (PMA), says the unchecked chlorine spray at the disinfection tunnels is hazardous. He says inhaled chlorine can trigger severe clinical symptoms.