Since the coronavirus emerged at the end of 2019, scientists have investigated how people can reduce their risk.
Early research suggests the infection is mild in four out of five cases, however, it is known to have killed more than 3 million people worldwide.
Lockdown combined with the UK's successful vaccination programme means deaths have plummeted. Just 17 deaths within 28 days of a positive coronavirus test were recorded on 27 April – a 98.7% reduction from 8 January's peak daily fatality toll of 1,325.
While it may sound reassuring, officials and scientists alike have repeatedly stressed "no one is safe until everyone is safe". In addition, no vaccine offers complete protection, particularly as new variants continue to emerge.
People aged 42 or over in England are being encouraged to book a jab. While the coronavirus' risk declines with age, younger people can still become critically ill or endure lingering long COVID post-infection.
With the pandemic not yet over, simple habits like maintaining good oral hygiene and staying active could help people stay safe.
Take a supplement
Official bodies like the NHS and World Health Organization (WHO) have not specifically recommended certain supplements amid the pandemic, citing a lack of evidence.
Nevertheless, the research surrounding certain vitamins and minerals is fairly compelling.
In April 2021, scientists from King's College London reported taking probiotics, omega-3 fatty acids, multivitamins or vitamin D had a "modest but significant" effect at warding off the coronavirus.
This benefit was only observed among women, however, possibly due to differences between a male or female's immune response.
The role of vitamin D in particular has been debated throughout the pandemic.
Coronavirus aside, the NHS stresses "everyone should consider taking a daily supplement containing 10 micrograms of vitamin D during the autumn and winter".
Since the pandemic emerged, statistics have repeatedly shown non-white people are more likely to both catch the coronavirus and become seriously ill.
In March 2021, scientists from the University of Chicago reported Black people with "deficient" vitamin D were up to twice as likely to catch the infection. The same was not true for the study's white participants, potentially due to "lighter skin increasing vitamin D production in response to sunlight".
While evidence may be limited, many have argued vitamin D is easily available and safe even at high doses, prompting hundreds of experts to sign an open letter urging governments make the "sunshine supplement" a coronavirus strategy.
With the results not explained by vitamin D, the sun's UVA rays may trigger the release of nitric oxide, a compound that has reduced the coronavirus' replication in laboratory studies.
Watch: Do coronavirus vaccines affect fertility?
Maintain oral hygiene
Brushing your teeth twice a day helps to ward off gum disease, decay and bad breath. While the habit may be an unconscious part of our daily routine, maintaining good oral hygiene has been described as "life-saving" amid the pandemic.
In February 2021, French scientists reported gargling with mouthwash that contains the antiseptic povidone iodine reduced coronavirus particle numbers in a patient's nose and throat. This may help prevent the infection's transmission.
A Qatar University study later suggested people with severe gum disease are almost nine times more likely to die with the coronavirus than infected individuals without the oral condition.
Although it is unclear, "inflammation in the oral cavity may open the door to the coronavirus becoming more violent", with gum disease making the mouth "leakier".
A team of international scientists has therefore recommended people take "simple but effective daily steps to maintain oral hygiene", like regularly brushing their teeth, using interdental sticks or even gargling with salt water.
While not everyone is convinced, others have claimed there is nothing to lose with keeping your teeth in tip-top condition.
The NHS recommends people brush their teeth with a fluoride toothpaste twice a day for around two minutes. Flossing, using interdental brushes and gargling mouthwash – not immediately after brushing – can also be effective.
Obesity is a known risk factor for coronavirus complications, with exercise helping people maintain a healthy weight.
Regular physical activity has been linked to a stronger immune response and lower levels of inflammation, a key driver of the coronavirus-related disease COVID-19.
Adults should be active every day, with anything being better than nothing.
Aim for at least 150 minutes of moderate-intensity exercise – like brisk walking, dancing or even pushing a lawnmower – a week. If pressed for time, do 75 minutes of vigorous exercise – such as jogging, fast swimming or skipping rope – every seven days.
Adults should also do strengthening exercises – like yoga, heavy gardening or even carrying children – on at least two days a week.
The WHO has recommended people who sit for much of the day, like office workers, exceed these exercise recommendations to offset their sedentary lifestyle.
Exercise also helps ward off frailty, another risk factor for coronavirus complications. Scientists from the University of Leicester have even reported slow walkers are almost four times more likely to die with the coronavirus.
Early in the outbreak, the UK's chief medical adviser Professor Chris Whitty stressed "if you are going to give up smoking, this is a very good moment to do it".
Health secretary Matt Hancock has also warned "it is abundantly clear from the research into previous coronaviruses [from the same virus class] that smoking makes the impact of a coronavirus worse".
US medics later reported heavy smokers, who have had the habit for over 30 years, are 89% more likely to die with the coronavirus.
Smoking is known to reduce a person's lung function and dampen their immune response.
Quitting is said to have immediate benefits, with lung health and breathing both improving relatively quickly.
Watch: What is long COVID?
Getting a good night's sleep may be easier said than done for some. Nevertheless, sufficient shut eye is critical for our overall health, with a US study suggesting every additional one hour of sleep reduces a person's risk of catching the coronavirus by 12%.
Enduring work-related burn-out every day was also linked to more than double the risk of developing the infection.
The WHO recognises burn-out as an "occupational phenomenon", defined as "a syndrome resulting from chronic workplace stress that has not been successfully managed". This leads to low energy, "feelings of negativism or cynicism" towards your job and reduced "efficacy" at work.
Chronic stress and insomnia have both been linked to inflammation and an impaired immune system.
People who struggle to nod off could try creating "sleep hygiene" habits, like going to bed and rising at the same time every day, even on weekends.
Winding down with a warm bath, light yoga, soothing music or a relaxing book can also promote a good night's sleep. Some also find writing a to-do list for the next day helps clear their mind of any distractions.
Try to also avoid using electronic devices, like smartphones, an hour before bed.
Creating a sleep-friendly environment – with a comfortable mattress, black-out curtains and no noise – can also help.
Burn-out and stress can be relieved by confiding in a loved one, exercising regularly, doing calming breathing exercises and setting aside time to relax. See a GP if your stress feels severe or cannot be eased.