KUALA LUMPUR: The government is expected to unveil a comprehensive guide on improving ventilation and indoor air quality in commercial and non-commercial buildings soon, amid the Covid-19 situation and spread of more transmissible variants.
The guide is expected to detail tailored practices for buildings, including workplaces, hospitals and homes, to reduce the risk of indoor virus transmission.
Tan Sri Dr Jemilah Mahmood, special adviser to Prime Minister Tan Sri Muhyiddin Yassin on public health, viewed this as one of the crucial steps in the country's multi-pronged approach to contain Covid-19 as the nation transitions to the "next normal".
The likeliest long-term outcome is that the virus becomes endemic, thus, requiring Malaysia to continuously apply the Swiss Cheese Model of pandemic defence at the individual and collective levels, she said.
"We need a diverse range of interventions, or layers of protection, providing a barrier to the spread of the disease, like slices of Swiss cheese in a stack.
"These layers consist of good hand hygiene, cough and sneeze etiquette, the use of face masks (or double-face masks, which is preferred in close and confined settings or in hospitals and crowded places) and physical distancing.
"Other interventions include aggressive testing and contact tracing, quarantine of exposed indi-viduals, restricting movements and closing borders.
"Another layer of protection is ensuring proper ventilation in buildings and, of course, vaccinations.
"I have maintained since last year that we have to learn to live with the virus for at least another two years.
"This is because this virus outsmarts us. It is 10 steps ahead of us, and that is the nature of viruses," she told the New Straits Times.
Understanding the major risk of indoor spread, she said countries that had vaccinated far more of their population than Malaysia were reversing their decisions on easing restrictions and face mask requirements.
In the United Kingdom, for example, there were strong calls for face masks to be made mandatory in classrooms, while Israel, which has achieved herd immunity, had reimposed indoor face mask requirements.
The United States Environmental Protection Agency said people, on average, spent 90 per cent of their time indoors.
The US Centers for Disease Control and Prevention said the odds of catching Covid-19 indoors were about 18 times higher than outside, mainly due to the lack of sunlight and open-air ventilation.
Thirteen months after the World Health Organisation (WHO) declared Covid-19 a pandemic, the agency formally recognised that the virus was airborne in April.
It cited that the virus could spread from an infected person's mouth or nose in small liquid particles when they cough, sneeze, speak, sing or breathe.
These particles range from larger respiratory droplets to smaller aerosols.
Aerosols are respiratory droplets less than 100 micrometres in diameter that can remain suspended in the air for hours, like smoke, and be inhaled. They can travel more than 2m and accumulate in poorly ventilated indoor air, leading to super-spreader events.
Droplets are particles larger than 300 micrometres and, due to air currents, fall to the ground in seconds within 2m of the source.
Dr Jemilah, who has been a vocal advocate for the formal recognition of aerosol spread in Malaysia, described WHO's acknowledgement as a "game-changer" as countries now better understood the importance of ventilation, using face masks and physical distancing in indoor environments, even for fully vaccinated people.
She said the ventilation policy should be in place before reopening the economy, as states transition to subsequent phases under the National Recovery Plan.
The Department of Occupational Safety and Health, Academy of Sciences Malaysia and various ministries — including Health, Human Resources, Housing and Local Government, Education, and Higher Education --— have to collectively work on coming up with this watertight policy that can be applied to different settings of a pandemic, she said.
"We do not have to start from scratch. WHO has published the 'Roadmap to improve and ensure good indoor ventilation in the context of Covid-19', which could be used as a guide, contextualised to Malaysian context.
"Singapore also came up with a guide along with simple graphics to educate people on ways to keep their indoor spaces safe. I hope the public can look at the WHO guidelines and begin practising it. Even vaccination centres have to take this seriously."
She said restaurants should redesign their eating spaces, being mindful of the direction of airflow in arranging tables. They should also increase the use of outdoor dining spaces and install Plexiglas barriers indoors if necessary.
"Without adequate ventilation, aerosols remain suspended in the air, becoming concentrated as time goes by, and the longer people linger in a contaminated area, the more virus particles they would likely inhale."