Disinfect with 'drone spray and chambers'? Expert says 'not recommended'

In Malaysia, under nationwide lockdown due to the virus, authorities have gone on a disinfection spree in areas with high case numbers to reduce the risk of further transmission.

But images of plumes of disinfectant spray fired from trucks into the air or from spray guns on to roads have riled health experts.

"Disinfecting roads is clearly not going to be impactful," said Christopher Lee, a former deputy director general in Malaysia's health ministry and an infectious disease specialist. "Waste of resources and man hours."

Malaysia's director-general of health Noor Hisham Abdullah said on Tuesday the government would be issuing guidelines to local authorities to make sure disinfection operations are carried out properly.

Back in Indonesia, telephone box-shaped disinfection chambers are being set up across the capital Jakarta, offering passers-by a quick blast to rid their clothes and skin of potential germs.

"I think it's good...I feel sanitized after touching a lot of things from the bus...I feel well-protected," said Jakarta resident Fany Anisa after exiting one of the chambers outside a bus stop in central Jakarta.

The private initiative being rolled out with the support of local authorities has been criticised by one expert who is advising the government's virus-fighting taskforce.

"It is not good for skin, mouth and eyes, it will cause irritation," said Wiku Adisasmito, a public health professor at the University of Indonesia.

Leong Hoe Nam, an infectious disease expert at Singapore's Mount Elizabeth hospital, said mass disinfections are eye-catching and may boost morale but are not effective virus controls.

"It would have better effect using a water cannon to disperse people and make them go home," he said.