Adults 18 to 49*

Asthma

2.8 times greater risk

Chronic lung disease, including COPD

5.6 times greater risk

Chronic heart disease

3.7 times greater risk

Diabetes

2.9 times greater risk

Any immunocompromising condition

3.9 times greater risk

Chronic kidney failure

14.8 times greater risk

Non-functioning spleen

7.1 times greater risk

HIV

6.1 times greater risk

Smoking

3.3 times greater risk

_{COPD=chronic obstructive pulmonary disease; HIV=human immunodeficiency virus.}

*Compared with healthy adults in the same age range.