SINGAPORE - In April, when Covid-19 infections showed no signs of abating and the evidence was growing in favour of wearing face masks to prevent transmissions, it became compulsory for everyone to don one that covered their mouths and noses as long as they were not at home.
People soon learnt that the authorities meant business when those who for whatever reason did not have a mask on faced fines.
And after several ugly incidents, mask-wearing, like handwashing and standing 1m apart, became a semblance of daily life.
But as the pandemic drags on, the resolve to comply with these measures has begun to falter.
Dr Annabelle Chow, principal clinical psychologist at Annabelle Psychology, told The Straits Times in September that continuous exposure to Covid-19 news and advisories could desensitise people to their importance.
A survey conducted by ST that month of 1,000 respondents found that 44 per cent were tired of following necessary health measures such as wearing a mask, checking in with SafeEntry, and limiting the size of physical gatherings.
In addition, mask wearing was also found to cause acne and irritation dubbed "maskne", a result of heat building up inside the mask, as well as chafing.
Dr Eileen Tan, a dermatologist at the Mount Elizabeth Novena Hospital, said she was seeing 15 to 20 per cent more complaints related to mask-wearing, which involved eczema, acne and skin infections.
Some patients had severely dry and itchy skin because of having to wear a mask for prolonged periods, like healthcare workers had to do.
The sheer number of disposable masks in use also posed a question mark for plastics pollution.
A study published in the Environmental Science and Technology journal in June estimated that 129 billion disposable face masks were used across the world every month throughout the pandemic.
Mask debris, latex gloves and other forms of personal protective equipment (PPE) have begun showing up in oceans, sounding the alarm among conservationists and non-governmental organisations (NGO) around the world.
For instance, French NGO Operation Mer Propre, which picks up litter along the Cote d'Azur, began finding such waste floating in the Mediterranean sea in as early as May.
In Singapore, five to six pieces of masks have been found during each clean-up organised by environmental volunteer groups at local parks, beaches and waterways.
While it is not yet known whether the PPE litter from the pandemic will increase the volume of plastic waste, Associate Professor Federico Lauro from the Singapore Centre for Environmental Life Sciences Engineering at the Nanyang Technological University said it is likely that the use of plastics has gone up due to shifts in consumer behaviour.
For instance, aside from mask usage, people have come to depend on food deliveries, which will increase the use of plastic bags and containers.
While there is far less plastic content in a mask, mask litter will still add to the plastic debris to the ocean, which will take a long time to degrade, said Prof Lauro.
"And as these tiny fragments of plastic are being ingested by marine fish and invertebrates, its chemical components may accumulate through the food chain. As a result, we may end up eating our disposable masks for dinner," he added.
However, it is undeniable that mask-wearing played its part in bringing the transmission of Covid-19 in the community to close to zero.
In fact, it also served to protect people from influenza this year.
Polyclinics are seeing close to a quarter of the number of patients for acute respiratory infections (ARI) than they did last year.
According to the Ministry of Health's Weekly Infectious Disease Bulletin, there was a daily average of 784 patients seeking treatment for ARI from Dec 13 to Dec 19, compared with 3,050 patients last year.
Among those seeking treatment, none has tested positive for the flu since June.
Associate Professor Alex Cook, vice-dean of research at the National University of Singapore's Saw Swee Hock School of Public Health, said masks when worn properly also halt the transmission of the rhinovirus, parainfluenza, adenovirus, and several other types of coronaviruses.
However, it is "hard to tell" if these heightened hygiene habits will persist in the long term, he said.
"One of the main reasons why we wear masks now is because of the risk of asymptomatic or pre-symptomatic infection that could be actively transmissible. The danger of that is sufficiently pronounced that an untargeted policy wherein everyone wears a mask is valuable.
"In normal times, however, we would not wear a mask to hedge against the risk of a rhinovirus infection, for instance, since the risk is low and historically tolerated," he added.
But a silver lining which could arise from this pandemic is that people coming down with a cold or the flu in future may follow the same practices as they did for Covid-19 - avoiding going to work, cutting out social contact, and wearing a mask to reduce the spread to others, he noted.
And if a future Disease X were to be a respiratory infection, he said, people would have benefited from the "dry run" offered by Covid-19, through the knowledge of what works and what doesn't, having technology and increased lab capacity, and knowing the importance of social distancing and mask wearing.