Ayse Semra Gureser

1 Introduction West Nile virus (WNV) was first isolated from the blood of a febrile woman in the West Nile region of Uganda in 1937 [1]. It is a mosquito-borne pathogen belonging to the family Flaviviridae and genus Flavivirus, and recently renamed Orthoflavivirus nilense by the International Committee on Taxonomy of Viruses [2]. It primarily circulates globally via a mosquito-bird enzootic cycle. Migratory birds play an essential role in spreading this virus into new areas.

Splenectomised patients are associated with lifelong risk of fatal overwhelming post‐splenectomy infection (OPSI), which is mostly caused by Streptococcus pneumoniae. Today OPSI cases can still be reported even in patients with appropriate vaccination. In our study, the levels of vaccine‐specific memory B‐ and T cells were compared between control and splenectomised patients to enlighten the underlying reason.