Individuals with the flu virus are generally contagious in the initial three to four days after their infection starts. Healthy adults could spread it one day before symptoms occur and up to 5 to 7 days after falling ill. Children and people with weak immune systems are at higher risk of getting infected and may pass the virus for longer than seven days.

It is crucial to take the necessary precautions to protect yourself and protect other people around you (cancer patients, diabetic patients, heart patients, pregnant women, etc.). People with these types of conditions are at higher risk of developing severe complications from the flu.

If a person is physically weak or has a weak immune system, he or she is more likely to get the flu as compared to others. Cancer patients have weaker immune systems due to their treatments and are more vulnerable to infections. It is recommended that patients with such conditions and their friends and family receive a flu shot.

• It is safe for patients diagnosed with most types of cancers to get the flu vaccine.
• If you are undergoing chemotherapy or have a fragile immune system (e.g., recently had a stem cell transplant), you should talk to your provider about when it is best to get your shot.
• If anyone around you has any flu symptoms, keep a safe distance, and practice good self-hygiene.

Live versus inactivated vaccines

Cancer patients should discuss with their doctor whether they can get vaccines or not. Typically, persons with a weak immune system should not get any vaccines that include a live virus. These vaccines may cause life-threatening infections in this group of people. Your doctor can guide you about which vaccines are safe for you.

The chances of catching the flu increase in cancer patients due to immunodeficiency; therefore, taking a flu shot becomes mandatory. However, it is advised that cancer patients consult with their doctor before getting any flu shot.

• The first step is to consult a doctor to learn when you can safely get the flu vaccine.
• If your cancer treatment is ongoing, you can take a shot at specific times only.
• During chemotherapy, doctors may suggest taking your flu shot between cycles or two weeks before treatment starts.
• The body's immune system and its immune response weaken due to strong and long term steroids and repeated radiation therapy. In this case, only a doctor can decide when it would be best for you to receive it.
• Doctors may recommend receiving flu shots only after 4-6 months after transplantation. A major problem following transplantation is that it lowers the number of immune cells (which defend against the flu) in the recipient's body.
• Immunotherapy helps the body fight cancer. If you are receiving it, ask your doctor for ways to prevent the flu.