Epidemiology and Cost of Infection with Human Parainfluenza Virus Types 1 and 2 in Young Children

Abstract

To determine the morbidity, costs, and epidemiological features of lower respiratory tract infections (LRIs) due to human parainfluenza virus types 1 and 2 (HPIV-1 and HPIV-2), we evaluated 1,213 children P < .001), while African-American children more often had pneumonia (RR = 1.85; 95% CI, 1.36–2.5; P < .001). Forty-five of 70 viruses recovered were HPIV-1 (17 cases) or HPIV-2 (28 cases). Together these two viruses were recovered from 49% of children presenting with croup, 10% of those presenting with bronchiolitis, and 12% of those presenting with pneumonia. Gender- and race-associated differences were documented in the group of children infected with HPIV-2: specifically, this group included more girls than boys (RR = 1.99; 95% CI, 1.02–3.88; P < .04) and more Caucasian than African-American children (RR = 2.64; 95% CI, 1.05–6.63; P = .027). These data extrapolate nationally to ∼250,000 emergency-room visits and ∼70,000 hospitalizations due to HPIV-1 and HPIV-2, with a cost of $50 million for the former and $140 million for the latter.