Why you should never kiss a child

There is a cognitive bias called the “curse of knowledge” (sometimes also the “curse of experience”). This happens when we mistakenly assume that everyone knows as much as we do about a given topic. For example, as a clinical microbiologist, I assumed that everyone knew that kissing a newborn on the head was a terrible idea.

Dr. Karan Raj, a surgeon with the United Kingdom’s National Health Service, recently made a TikTok video warning people about the dangers of kissing a baby, and judging by the thousands of comments, it was news to many on the social network.

Late last year, UK charity The Lullaby Trust released the results of a survey showing that 54% of new parents and parents-to-be “would allow friends and family to kiss their newborn without realizing the risk of serious infection.”

But why is this so dangerous?

A baby’s immune system is not yet fully developed at birth, so the risk of contracting a serious infection is much higher.

During the first three months or so of life, a person’s immune system has fewer infection-fighting innate immune cells, such as neutrophils and monocytes, compared to adults. This means that infections that cause mild symptoms in adults or older children can be life-threatening in infants.

An example is herpes virus infection. Cold sores cause cold sores in adults, but newborns can quickly become seriously ill after contracting the virus. If herpes only affects the eyes, mouth, or skin, most recover with antiviral treatment. But if the virus becomes systemic and affects organs, the infection becomes much more serious and can even be fatal. The smaller the baby, the more vulnerable he is to herpes infection, especially in the first four weeks after birth.

Newborns are also more vulnerable to infectious bacteria than older children and adults. First of all, to infections with intracellular pathogens (bacteria that can penetrate and survive inside the cells of the host), such as group B streptococci (GBS). These bacteria usually live in the gastrointestinal and genital tracts of their hosts without causing disease. GBS infections in infants cause sepsis, pneumonia, meningitis, and blood infections.

Infants are also susceptible to infections caused by strains coli which are not harmful to adults and cause pneumonia, meningitis and sepsis, all of which can have serious consequences.

Show affection safely

Parents of very young children should not feel uncomfortable asking visitors not to kiss or touch their child. If the visitor truly cares about the baby’s well-being, his request should not be offended. And parents shouldn’t feel like they’re exaggerating.

The kindest thing any visitor can do is not to put your baby in danger, but if you have to kiss him for good reasons, there are some things you can do to reduce the risk of infection.

First, be sure to wash your hands thoroughly. And avoid kissing him on the lips or face; do this on the foot or back of the neck. If you have any active infection, consider whether you really need to visit your newborn, especially if he is less than a month old.

Herpes infections are especially dangerous for very young children, so cover any cold sores with a bandage.

If you don’t feel well but feel you can’t miss the appointment, wear a mask and stay away from your child, especially if they have a respiratory illness.

Always keep in mind that children are very vulnerable to infections. Although kissing is a sign of affection, it can seriously make your newborn sick, and if it does, you’ll feel terrible.