Safety of 7vPCV vaccination in pediatric alloHSC transplant recipients. (A) Frequency of local reactions and advanced local reactions (≥ 5 cm in diameter, pain interfering with limb movement) following 7vPCV vaccination. Error bars indicate 95% CIs. Frequencies were significantly different for redness and swelling between the first and third vaccination (P ≤ .05) as determined by Fisher exact test. No significant differences were found between age groups except for swelling after the first vaccination, which was more frequent in the younger (1-5 years) age group (27.8% versus 5.9%; P = .04) (B) Frequency of fever as the most common systemic adverse event. The left panel shows the overall rate of fever (body temperature ≥ 38.0°) and high-grade fever (body temperature ≥ 39.5°) following the first, second, and third 7vPCV vaccine for the entire group. The right panel compares fever rates between the younger (1-5 years; n = 18) and older (6-16 years; n = 35) age group with significant differences following the second and third vaccination (P <.05) as determined by Fisher exact test. No other significant differences were found. Additional systemic adverse events considered potentially related to study medication by the investigators include gastroenteritis (n = 2), unspecific exanthema (n = 1), herpes labialis (n = 1), and persistent thrombocytopenia leading to drop out from the study (n = 1).