Why Kids are More Susceptible to Falling Sick During Winter

As the days get shorter and cooler, every parent across New Zealand collectively girds their loins as cold and flu season descends upon us. According to the Centers for Disease Control and Prevention, the average adult gets two to three colds yearly, with children typically getting even more.

But what is it about winter that makes it feel like every child has a perpetual sniff, sneeze or cough? It's not due to being just cold or wet, as many of us are incorrectly led to believe from our younger years – but instead how we act to get away from those factors that make us sick. 

To get sick, one has to be exposed to an infection – and in winter, there's plenty of opportunity for just that.   

One of the critical reasons kids tend to get sick more often in winter is that we all spend more time indoors, which means enclosed spaces, close proximity to each other, and a lot more face-to-face engagement. 

That increased time spent indoors leads us to another guilty party – humidity. In the colder months, decreased humidity means that any nasal and throat droplets of around 1.5 micrometres in diameter tend to stay in the air a lot longer than they usually would. Since most of us are in each other's breathing zones indoors (about 1 meter), it's the perfect environment to spread some germs effectively.     

And then there's cold air. Although cold air in itself won't make you sick, there is a theory that viruses tend to survive for longer in cooler weather because they're able to circulate more easily. Additionally, some studies have shown that colder temperatures may slow the immune system's normal response, suppressing the virus's ability to replicate. Our noses, a natural defence generally, are less likely to be effective in the cold air as the tissue inside can become dry and cracked, making the cilia (tiny hairs) inefficient at catching and expelling germs.   

Another key contributor is that we don't generally get enough access to sunshine in the winter. The little we get is often lower in UV radiation than in summer, affecting our Vitamin D levels.  

So, what can you do to encourage your children to stay healthier this time of year? 

The first line of defence is regular hand washing for at least 20 seconds with soap, especially before mealtimes and after blowing noses. Remember that it's important for kids to see mum and dad leading by example and regularly washing their hands too. 

It's also an ideal time to encourage sneezing and coughing into elbows for those times when water or hand sanitiser aren't immediately available. 

Try to discourage your children from touching their face, eyes, mouth or nose, particularly if they haven't recently washed their hands and have

been touching surfaces like doorknobs, handrails, computer keyboards etc. 

And be sure to get your kids outdoors for plenty of fresh air and exercise, as these are factors that positively support a healthy immune system, especially when used alongside a diet rich in fruits, vegetables, and other nutrient-dense foods.  

You could also consider a Vitamin D supplement to boost their immunity during these trying winter months.

And the last tip – ditch the toothbrush after being sick. You may not be able to re-catch your cold (although things like strep are a different story), but your germs would love the opportunity to jump ship onto the other brushes around it.