Monday Pharmaceutical Mystery: February 25

Why is this patient requesting the flu vaccine in the middle of June?

It is the middle of June and a male, aged 20 years, comes into your pharmacy with a written prescription for Haemophilus influenzae vaccine. You have never seen this patient before and you notice the prescription is written by a surgeon. You inquire more and find out that the patient has chronic idiopathic thrombocytopenic purpura. He said that his usual pharmacy could not get this vaccine because it was not flu season, and the CDC had not yet released the new batch of flu vaccines. When he told this to the surgeon, the surgeon sent him to your pharmacy and said that you would order it.

Mystery: Why is this patient requesting the flu vaccine in the middle of June? Also, all pharmacies have access to the same vaccines. What is the difference between the 2 pharmacies?

Solution: The first pharmacy mistakenly thought the prescription was for the influenza virus vaccine. But the H influenzae is a Gram-negative, coccobacillary, facultatively anaerobic pathogenic bacterium belonging to the Pasteurellaceae family.

This vaccine is part of the septectomy protocol used to treat resistant and chronic ITP. Surgeons will often order such vaccines prior to removing the spleen since it involves the immune system.


Centers for Disease Control and Prevention. Vaccine Information for Adults: Asplenia and Adult Vaccination. CDC website. Updated May 2, 2016. Accessed February 22, 2019.