KUALA LUMPUR, June 26 — The Health Ministry has again reiterated its stance on the use of "disinfection tunnels” against Covid-19, labelling such devices as ineffective and possibly harmful.

In discouraging their use, Health Director-General Datuk Dr Noor Hisham Abdullah said there was no clinical evidence to suggest such tunnels were beneficial or even able to safeguard an individual against diseases.

He then cited statements issued by the World Health Organisation (WHO) and the Health Ministry itself on the proper use of disinfectants.

"We are worried that using this tunnel, firstly it is not going to disinfect a person because the virus is in the body and not on the surface. And on the surface, (chemical) exposure is in a short period of time and not adequate as well.

"Third, we are worried because the chemical sprayed into an individual may cause irritation to the skin and eye, it may also trigger asthmatic attack for example, so we do not encourage the usage of these tunnels. So I think that statement is very clear from the Health Ministry,” he said during a press conference.

Dr Noor Hisham was earlier asked to respond to reports of several schools using such devices to disinfect students after secondary schools across the country reopened on June 24 after almost three months of closure due to Covid-19.

Previously in April, Dr Noor Hisham said the Health Ministry does not recommend so-called "disinfection boxes” being proposed as a countermeasure to Covid-19.

At that time, Dr Noor Hisham said the ministry’s technology evaluation branch conducted assessments on several models of the disinfection boxes from various countries and also on the existing models in the country and found out that it is not effective.

According to a WHO advisory, the international health body also said spraying of individuals with disinfectants (such as in a tunnel, cabinet, or chamber) is not recommended under any circumstances.

"This practice could be physically and psychologically harmful and would not reduce an infected person’s ability to spread the virus through droplets or contact.

"Even if someone who is infected with Covid-19 goes through a disinfection tunnel or chamber, as soon as they start speaking, coughing or sneezing they can still spread the virus,” it said.

It added that the toxic effect of spraying with chemicals such as chlorine on individuals can lead to eye and skin irritation, bronchospasm due to inhalation, and potentially gastrointestinal effects such as nausea and vomiting.