Nothing says “happy birthday” like blowing your germs all over a piece of food and handing it to your coworkers. Birthday candles are a tradition we’ve somehow accepted until now, but will the pandemic extinguish them for good?
“Covid aside, it’s a bit of a disgusting habit, putting all your spittle over a cake before your family and friends eat it,” Professor Paul Hunter, a professor of medicine at UEA and an expert in infectious diseases tells HuffPost UK. ”Certainly at the moment with Covid-19 around, I wouldn’t encourage it.”
A 2017 study published in the Journal of Food Research highlighted just how gross the tradition is. Volunteers were instructed to blow out birthday candles after eating pizza. The researchers found blowing out the candles resulted in 1400% more bacteria on the icing compared to when the candles were not blown out.
“Due to the transfer of oral bacteria to icing by blowing out birthday candles, the transfer of bacteria and other microorganisms from the respiratory tract of a person blowing out candles to food consumed by others is likely,” the researchers said. Eww.
Although no specific studies on Covid-19 and birthday candles have been conducted, it’s highly likely the ritual would increase Covid-19 transmissions. We know the virus can spread in droplets and smaller aerosols, which are expelled from the nose and mouth when a person is chatting, laughing, singing and even breathing. These particles can then be inhaled into the nose, mouth, airways and lungs of others, and cause infection.
One solution is to use transparent “cake shields”, like those designed by the US company Top It, which is selling shields from $4.99 (£3.92) to fit a single slice to $14.99 (£11.79) for a whole cake. But remember, Covid-19 can spread by touching contaminated surfaces, so be sure to wash your hands extremely throughly if you’re handling the shield.
If you’re celebrating a birthday within your household or bubble, though – where you’re already mixing and likely to catch the virus if one person becomes infected – blowing out candles probably won’t make much difference, says Professor Hunter.
“If I bought a cake for my wife’s birthday and put candles on and it’s just the two of us, there’s no issue about her blowing the candles out,” he says. ”Similarly, if my son and his partner and their child have a party just the three of them, there’s no issue in that context, because it’s in the household.
“The issue is if the neighbours then bring their kids around to celebrate the party, that’s when I’d be twitchy about it.”
Will we ever blow out candles again? The answer remains uncertain and probably depends on if and when we get a vaccine and herd immunity. For now, stick to blowing out a candle on your individual pre-cut slice well away from another human being if you truly must. Sorry to be the party poopers.