Temporal changes in causes of death in children with sickle cell disease. Three categories of death are shown on the y-axis: deaths due to acute chest syndrome (ACS) and multiorgan failure syndrome (MOFS), deaths due to sepsis, and deaths of all other causes. Together, deaths due to ACS and MOFS are now more common than fatal sepsis. Notably, no member of the cohort has died from Haemophilus influenzae type b sepsis () or Streptococcus pneumoniae sepsis () since the availability of the protein-conjugate vaccine against either bacterium (dotted lines).