Why you must change your toothbrush after recovering from cough and cold

Toothbrushes play a crucial role in maintaining oral hygiene, but they can also become breeding grounds for bacteria and viruses, especially after an illness. Many people overlook the importance of replacing their toothbrush after recovering from a cough or cold, assuming that rinsing it under water is enough. However, research and expert recommendations suggest otherwise.


During a cough or cold, the body fights off viruses and bacteria, which can spread to various surfaces, including your toothbrush. When you brush your teeth while sick, germs from your mouth transfer to the bristles. Since toothbrushes are often stored in bathrooms—a humid environment ideal for microbial growth—these germs can continue to thrive.



Studies have shown that viruses like the flu, rhinovirus (which causes the common cold), and even bacteria like Streptococcus can survive on surfaces for hours or even days. If you continue using the same toothbrush after recovering, you may risk reinfecting yourself or spreading germs to others, especially if toothbrushes are stored close together.


Expert explains why you must replace toothbrush after illness

"While there's no direct proof that viruses stay infectious on a toothbrush, research confirms they can harbor bacteria, fungi, and other pathogens—some even forming resilient biofilms. When you have a cold this can make you even more vulnerable to other infections during that time," explains Dr Kunal Sood. Sharing a post on social media platform Instagram, Dr Sood said, "Toothbrushes collect microbes over time, even if they look clean."


He suggests replacing the toothbrush every 3-4 months. "Worn out bristles don’t clean as effectively and can leave more plaque behind," he says. "A fresh toothbrush helps maintain good oral health and may even lower the risk of some systemic diseases," he adds.


With this, it's important to address prevailing myths around toothbrush usage. Many people believe that simply running a toothbrush under water after brushing removes all germs. This is a big myth. Studies show that bacteria and viruses can still cling to bristles, making thorough disinfection or replacement necessary.


Many people believe that toothpaste kills the germs. While toothpaste contains antibacterial properties, it doesn’t eliminate all harmful microorganisms. Germs from saliva and food particles can still accumulate on the bristles.


Good oral hygiene doesn’t just prevent cavities and gum disease—it also plays a vital role in overall health. Studies have linked poor oral hygiene to systemic conditions such as heart disease, diabetes, and respiratory infections. Since the mouth is a gateway to the body, maintaining cleanliness is essential.


Best practices to follow

You must always store the toothbrush properly. Keep your toothbrush in an upright position to allow it to air dry between uses. Avoid storing it in a closed container, as moisture buildup promotes bacterial growth. If you share a bathroom, store toothbrushes separately to minimize cross-contamination.


Always sanitize your toothbrush. While brushing with a toothbrush after falling sick, sanitize it periodically by soaking it in an antibacterial mouthwash for a few minutes.

Alternatively, you can soak the bristles in hot water or hydrogen peroxide to minimize bacterial load. Others use UV sanitizers to destroy germs, although replacing the toothbrush is still the best.


Never share your toothbrush with anyone. Never share a toothbrush, even with family members, since it can spread bacteria and viruses. Label toothbrushes in shared areas to avoid accidental use by others.


Replace your toothbrush immediately after recovering from a cough, cold, flu, or any bacterial infection. If you use an electric toothbrush, change the brush head rather than the entire device.