Vaccination can prevent diseases burdened by high mortality and their complications among patients with altered immunocompetence.

Limited data are available on safety and effectiveness (e.g. optimal serological response) of vaccines in patients with altered immunocompetence.

Vaccination during early course of diseases or before the onset of immunosuppression is recommended, since disease progression may further impair immunity and vaccine efficacy.

While vaccination against Streptococcus pneumoniae and influenzavirus is generally recommended in all patients with altered immunity, other vaccines should be administered according to local recommendations, age and underlying disease.

Experts in vaccination should be involved to increase vaccine coverage in patients with altered immunocompetence.

There is an urgent need for large prospective studies on vaccine efficacy in specific subsets of patients with altered immunity.