Increase hospital isolation wards to avoid airborne COVID-19 infections - Experts

KUALA LUMPUR: The uncertainty surrounding the current pandemic situation, with daily cases hovering around 4,000 to 5,000 cases, is still a cause for concern even after three weeks of a nationwide total lockdown.

The number of COVID-19 hospitals and quarantine and low-risk treatment centres (PKRC) have been increased in an effort to ensure adequate health facilities across the country to cater to COVID-19 patients.

Ventilation in wards or halls of COVID-19 hospitals or treatment centres is of utmost importance as airborne infections can happen at an alarming rate if the ventilation system is not according to specification or maintained well.

The World Health Organisation (WHO) has also stated previously that enclosed buildings with inadequate ventilation have a higher risk of COVID-19 infections compared to being outside of buildings.

This is because the SARS-CoV-2 virus can be airborne for up to eight hours and travel as far as two metres, exceeding six metres at times, based on research conducted by ventilation experts from local universities recently.

The virus which sticks to micro-surfaces can spread through the air and if preventive measures are not taken, it can lead to the risk of infection to hospital patients and employees in non-COVID-19 wards, said Universiti Kebangsaan Malaysia (UKM) Earth Sciences and Environmental Department senior lecturer, Assoc Prof Dr Mohd Shahrul Mohd Nadzir.

It will not only disrupt the hospital's operations but can cause complications to patients in those wards as they would have to isolate themselves and their close contacts would need to undergo screening tests and be quarantined.

"Therefore, ventilation guidelines in health facility buildings such as those issued by WHO should be applied to hospitals or centres treating COVID-19 patients to ensure other patients or health employees are not exposed to airborne infections," he told Bernama, adding that the recycled air in enclosed and air-conditioned areas would help spread the virus in the air via aerosol.

WHO issued a reference entitled 'Roadmap to Improve and Ensure Good Indoor Ventilation In the Context of COVID-19' that is specific to three types of buildings, health facilities, residential and non-residential buildings.

Commenting on the matter, National Institute of Occupational Safety and Health (NIOSH) indoor air quality expert Nor Mohd Razif Noraini said a special ventilation system for isolation wards is needed in a hospital environment to handle infectious diseases such as COVID-19.

For spaces and normal wards that have been converted into infectious disease wards like COVID-19 wards, there should be preparation and improvements to existing ventilation systems to enable the safe dispersal of contaminants, including bacteria and virus.

"The risk of infection can be reduced by creating a pressure differential (negative pressure) in the ward area.

"Other measures that can be practised include creating a temporary isolation area through the use of dividers in a large area that will help regulate the air flow," he said.

The use of technology such as the filtering of contaminants can also reduce airborne virus in the area as many existing hospitals in Malaysia were designed and built based on current health needs and the country's population size.

"Therefore, when a pandemic occurs, isolation areas such as isolation wards with good ventilation systems are very much needed and there are very few such areas throughout the hospitals in Malaysia," he said.

In order to ensure there are adequate isolation facilities in the future, upgrading existing hospitals, and designing and building new hospitals with a higher ratio of isolation wards to normal wards is necessary.

In addition, conversion of normal wards to temporary isolation wards can be done by outfitting existing wards and areas with portable ventilation.

"The use of other areas, such as treatment centres, need to ensure proper ventilation for such temporary isolation systems.

"This includes using exhaust fans and other ventilation techniques, like local exhaust ventilation," he added.

Based on his observation, he said the steps outlined have been practised by COVID-19 treatment wards adding that it was not known whether these steps were in line to suggested specifications and the level of their effectiveness had yet to be determined.

This is largely due to the lack of temporary guidelines or policies in Malaysia regarding effective ventilation for isolation areas during pandemics, he said.

-- BERNAMA