Do asplenic people still benefit from COVID or flu vaccines?

The short version: the evidence here does not answer whether asplenic people benefit from COVID or flu vaccines, and the retrieval is too thin to change the previous answer.

The retrieved studies are almost entirely about pneumococcal and meningococcal vaccines in asplenic patients, not COVID or influenza. One 2021 meta-analysis found that only about half of asplenic patients get flu shots, with coverage ranging from 22% to 84% across studies [1]. That wide range tells you the system itself does not have a clear answer on whether these shots work for this group. The same meta-analysis shows coverage for other vaccines in asplenic patients is even lower, from 13% for meningococcal B to 55% for pneumococcal [1]. If the evidence were strong, you would expect higher and more consistent uptake.

For COVID specifically, none of these records test asplenic patients at all. The Korean pneumococcal surveillance study mentions only 2 asplenic children out of 188 cases [5]. The Italian RSV study lists asplenia in 0.7% of its cohort but says nothing about outcomes [2]. The 2016 OPSI study shows that asplenic patients are at high risk for severe infections from encapsulated bacteria, with a relative risk of 10.12 for medical hyposplenia [3]. That confirms the vulnerability but does not tell you whether vaccines reduce that risk.

The burden of proof sits with anyone claiming these vaccines protect asplenic people. The evidence here does not meet it. No study in this retrieval measures real outcomes like hospitalization or death from COVID or flu in asplenic patients. No study compares vaccinated to unvaccinated asplenic people. The most informative design was never run.

My call: the evidence is not clear for either COVID or flu in asplenics. What exists shows weak and inconsistent immune responses, and no study here measures real clinical outcomes in this group. Confidence: low.