FA16 Immunization Module’s Updates

Vaccinating Immunocompromised Patients

Recent studies suggest that an important factor in determining the effectiveness of vaccines in immunocompromised patients may rely on the timing of the vaccination with respect to chemotherapy.

One study compared the response towards an influenza vaccine to the timing of the administration of chemotherapy [1].  The quality of the vaccine response was analyzed by identifying seroconversion.

Seroconversion is the time in which a patient first develop antibodies in high enough levels that makes antibodies detectable. This study defined a positive humoral response if there was a four-fold or greater increase in antibody titer after vaccination.  In healthy individuals, antibodies usually appear within one week of exposure to the vaccine.  However, in immunocompromised individuals, seroconversion might not occur until the third week.

In the group of patients with HIV who received influenza immunization between their chemotherapy courses, 93% showed seroconversion.  This was significantly higher when compared to patients who received influenza immunization at the time when they were administered chemotherapy.  Only 50% of them showed seroconversion.

Therefore, these results indicate that humoral responses may possible by improved if influenza vaccines are given between chemotherapy courses rather than concurrently with chemotherapy courses.  This recommendation is supported by another study whose results showed that immunocompromised individuals who received influenza vaccination within 7 days receiving chemotherapy had a very poor humoral response [2]. 

Sources:

[1] http://www.sciencedirect.com/science/article/pii/S1473309909701756#fig1

[2] http://www.nature.com/bjc/journal/v82/n7/pdf/6691088a.pdf

  • Emily McLaughlin
  • Jeremy Huckleby Jeremy
  • Omar Calderon