Can You Get a Flu Shot When You Have a Cold?

People who get sick with the flu generally recover on their own within one week. Still, some develop severe symptoms and complications. In very severe cases, complications can result in death. Getting vaccinated against the flu can help you avoid severe illness during flu season.

But what if you come down with mild cold symptoms, like a stuffy nose and sore throat, right before you get a flu shot? You might wonder whether getting the flu shot is safe when you have a cold.

Mild cold symptoms don't affect the efficacy of the flu shot. However, if your symptoms are moderate to severe, it's a good idea to consult a healthcare provider.  

Should You Get a Flu Shot if You’re Sick?

For the most part, getting a flu shot while sick is safe. Generally, mild cold symptoms will not impact the efficacy of a flu shot. However, getting a flu shot while you're sick might depend on the severity of your symptoms, Aditya Gaur, MD, director of clinical research at St. Jude Children's Research Hospital, told Health. 

"Typically, someone with a mild illness can be given a flu shot," explained Dr. Gaur. In contrast, "[if] it's a moderate or severe illness, vaccination is postponed until the person recovers."

Delaying your annual flu shot might increase your risk of getting sick. Flu season typically occurs during the fall and winter, with cases rising from December to February. So, try to get your flu shot before then, ideally in the fall, even if you have mild cold symptoms.

"A mild illness is not a contraindication to getting the flu shot, and delaying it can potentially result in a missed opportunity for vaccination and related protection against flu," noted Dr. Gaur.

When To Postpone Your Flu Shot

You should consult with a healthcare provider before receiving either form of the vaccine (nasal spray or injection) if you have moderate to severe illness with or without fever.

"[A] healthcare provider may delay giving the flu shot to avoid confusing signs and symptoms of their illness with side effects of the vaccine," added Dr. Gaur.

For example, some people have muscle soreness, headaches, and fever after receiving a flu shot. If you already have those symptoms, it might be hard to tell whether you are reacting to the vaccine.

Can You Get Sick From a Flu Shot?

The flu shot can't give you the flu. It's made up of a "dead," also known as inactivated, form of a flu virus. In contrast, the nasal spray vaccine comprises a live flu virus. However, the virus is weak or attenuated, so it can't get you sick.

Flu-like symptoms after getting a flu shot do not mean you are infected. In fact, flu-like symptoms are common side effects after receiving any vaccine.

Instead, if you get sick in the first few days after your shot, you might have caught the flu virus before your body had time to form antibodies. On average, your body needs about two weeks to develop vaccine-induced immunity.

How To Protect Against the Flu

No vaccine guarantees complete protection from illness. However, the flu shot is one of the best ways to protect yourself as much as possible from getting sick or having severe symptoms.

Also, when more people get the flu shot, the virus is less likely to spread to high-risk populations like people with weak immune systems, older adults, and infants. Often, those people are more likely to develop severe symptoms if they get sick.

In addition to getting the flu shot annually, other ways to protect against the flu include:

• Stay socially distant from people who are sick or if you are sick.
• Stay home if you are sick.
• Cover your mouth and nose with the crook of your elbow if you cough or sneeze.
• Wash your hands regularly. 
• If you cannot access soap and water, hand sanitizer with at least 60% alcohol helps kill flu viruses.
• Do not touch your face (e.g., your eyes, nose, and mouth) without washing your hands. 
• Clean and disinfect any surface or items that people touch.

A Quick Review

Annually getting the flu shot is one of the best ways to protect against the flu and reduce the risk of severe symptoms. You do not need to postpone your appointment if you have mild cold symptoms before getting a flu shot. However, talk with a healthcare provider if you have moderate to severe symptoms.