In the past, my oncology practice instructed cancer patients undergoing active chemotherapy not to get the flu vaccine, as it was felt the immunosuppressive therapy they were receiving would render the vaccine ineffective. Instead, we recommended heard immunity, which is telling their friends and loved-ones to get vaccinated, and thereby offering some protection for the patient.
In light of the most recent CDC recommendations, and considering the real risk influenza poses to cancer patients, we have recently changed our stance. During a given flu season, between 21 and 33 percent of cancer patients who are admitted to the hospital with respiratory symptoms may test positive for influenza. Furthermore, the influenza mortality rate is very high, with reports between 11 and 33 percent for cancer patients. (Boltz, 2012)
Symptoms of the flu may include fever, cough, sore throat, runny nose, body aches, headache, chills, and fatigue. Some people may develop vomiting and diarrhea. People may also be infected by the flu and have respiratory symptoms without fever.
Those infected with the flu can spread it to others as far as six feet away. It's believed that flu viruses are spread mainly by droplets produced when people cough, sneeze, or talk. These droplets can then end up in the mouths or noses of nearby individuals, or inhaled through the lungs. Less often, a person might be infected by touching a surface with the flu virus on it, and then touching their nose or mouth. (CDC, 2012)
As we all know, cancer patients going through active treatment are considered to be in an immunocompromised state. This is especially true for patients during the nadir period, when the counts are at their lowest. Thus, it's important to provide these patients with added protection against the flu.
Multiple strategies exist for vaccination of patients on active therapy. If a patient will finish a planned course of treatment during the early/mid influenza season (Nov/Dec through March, peaking in February), some experts feel vaccination should be delayed until chemotherapy is completed. The optimal time for administration following completion of chemotherapy is not known, however, the WBC should have recovered to at least 1000, with a preferable wait time of at least three to four weeks after the last dose of chemotherapy is administered. (Pollyea, 2010)
For patients who will not finish a planned course of chemotherapy until the late influenza season, or who are receiving ongoing therapy, the flu vaccine must be administered while on treatment. This should occur at a time in the chemotherapy cycle that is the farthest out from chemotherapy dosing, and when the WBC is at least above 1000 (e.g. during week three of a 21-day cycle). (Pollyea, 2010)
It's important to note that cancer patients should not receive the nasal spray vaccine, as this is a live virus. Instead, the actual shot should be given, which is made up of inactivated (killed) viruses.
It goes without saying that caregivers of cancer patients should also receive the flu vaccine. If those in closest contact with patients can stay well, the patients' odds of avoiding illness are greatly increased.
As we come into the current flu season, it's important for oncology providers to educate both patients and caregivers about the flu, and the importance of vaccination. And of course, go get your flu shot if you haven’t already!
References:
- Boltz, K. (2012). Influenza vaccination for cancer patients. Retrieved from http://www.chemotherapyadvisor.com Accessed October 14, 2012.
- Centers for Disease Control and Prevention. (2012). Cancer, the flu, and you. Retrieved from http://www.cdc.gov/cancer/flu/#4 Accessed October 14, 2012.
- Pollyea, D.A. (2010). Utility of influenza vaccination for oncology patients. Journal of Clinical Oncology, 28(14), 2481-2490.