The cold and flu season isn’t over just yet, and sometimes, no matter how much care we take to remain healthy, a dreaded bug can still take us down.
And among all the coughing and sneezing, we might wonder what exactly is causing our misery. Could it be one of the many strains of the common cold virus, or is it the flu? Or could it be both?
As much as you might put up a fight, there are times you can get a strain of a cold and the flu at the same time. As Dr Kevin Bonham explains on Science Blogs in 2013, this state is called a "superinfection", and that when this happens, your immune system reacts in a certain way.
How the cold and flu can overlap
When you're infected with one virus, your immune response makes it inhospitable for any other virus to attack, which means it is less likely that a second infection will take hold while your body is fighting the first, explains Science Focus. However, although it is rare for anyone to catch a cold and the flu at the same time, it is possible.
The common cold and the flu are caused by different families of viruses. Although there are no published studies looking at the concurrence of both, there is still a slim chance of it happening, said Dr Schaffner to Health.com.
A cold remains up in the nose and sinus area, whereas the flu can enter deep into the lungs and cause complications, especially for those with weaker immune systems. Cold symptoms are also milder and more common, which is why it is known as the "common cold". The most common cause of colds is the rhinovirus. According to the Centers for Disease Control and Prevention (CDC), adults have an average of two to three colds per year.
The flu, on the other hand, is more severe than a cold and may cause symptoms of fever, headache, sore throat, body aches and even some gastrointestinal symptoms – and can even be fatal. The World Health Organization reports that flu epidemics result in three to five million cases of severe illness and about 290 000 to 659999 deaths each year.
Although symptoms differ, the bottom line is that both viruses attack your respiratory tract, and there’s no reason they couldn't infect you at the same time, added Schaffner. Dr Bonham also explains that if the two viruses you contract are very similar, like colds and flu, the first stage of your immune system's response would kick into high gear and the body would go into an "antiviral state" and fight off the two viruses in identical ways, whereas the second stage would target the two viruses individually.
Is it dangerous to have both viruses at the same time?
While having both a cold and the flu concurrently would make you feel downright miserable, the good news is that your body can fight two infections at once. Interestingly, Schaffner explains that you likely wouldn't be able to tell that you have both at once, but that you would certainly feel much worse than if you only had one.
The more important concern is that, according to a 2017 review published in Frontiers in Microbiology, there is actually a higher ability for a bacterial infection, such as pneumonia, to piggyback onto an existing influenza infection. To safeguard yourself from this it is strongly advised that you get the flu vaccine, to reduce your risk of catching the flu as it is the best method to protect yourself against the flu virus. Other measures include among others regular hand washing, cleaning surfaces with disinfectant soap, and avoiding touching objects in public spaces.
And when you can’t distinguish whether you're suffering from a cold or the flu, here are 7 warning signs that it's more than "just a cold".