Most individuals have experienced at least a mild version of the flu at some point in their life. Every year, somewhere between 3 and 11 percent of the US population will contract the flu virus.
Typical flu symptoms include fever, chills, sore throat, runny or stuffy nose, cough, head and body aches, or fatigue. It’s common for an infected individual to have only a few of these symptoms manifest strongly, and not everyone will experience every single symptom. It’s also common to confuse the flu with the common cold, especially as not everyone with the flu will experience a fever – a symptom considered a hallmark of the virus. But, the flu differs from the cold as it tends to come on more suddenly. The onset of these symptoms is usually two days but can range from one to four days.
While the flu is usually no cause for concern for healthier individuals, it can often cause or trigger more significant health issues in children, older people, or people with compromised immune systems. These complications could include bacterial pneumonia, ear infections, sinus infections, and worsening of chronic or pre-existing medical conditions.
But can the flu be asymptomatic? Research points to a resounding yes. Quite a large portion of people won’t experience any symptoms – one out of every three people could be asymptomatic. The lack of symptoms in certain people could be due to various reasons, such as pre-existing partial immunity. Some individuals might even have an immune system response that fights off the virus before symptoms even have a chance to show up.
In a study from The Lancet Respiratory Medicine, seasonal or pandemic influenza is asymptomatic in most people with confirmed infection. Roughly 20% of the people who hadn’t received a flu vaccine had evidence of influenza infection, but up to 75% of the infected were asymptomatic. The proportions did not vary significantly between seasonal and pandemic influenza.
There are multiple studies on asymptomatic flu cases that all yield wildly varying results, so while it’s clear that asymptomatic flu cases do exist, it’s important to question how many of these types of cases exist and contribute to flu transmission.
It’s important to note that while asymptomatic individuals are free from many of the miserable symptoms we associate with contracting the virus, they can still transmit flu to others. Because of this, it’s essential to be vigilant about your health and hygiene during flu season. And this also makes getting your yearly flu vaccine the most important thing you can do to help reduce transmission of the flu virus.
Flu shots are key to staying protected. Call Passport Health or book online to schedule your flu vaccination appointment today.
Written for Passport Health by CJ Darnieder. CJ is a freelance writer and editor in Chicago. He is an avid lover of classical music and stand-up comedy and loves to write both in his spare time.