Background: Acute respiratory infections (ARIs) result in millions of
illnesses and hundreds of thousands of hospitalizations annually in the
US. The responsible viruses include influenza, parainfluenza, human
metapneumovirus, coronaviruses, respiratory syncytial virus (RSV), and
human rhinoviruses. This study estimated the population-based
hospitalization burden of 18 respiratory viruses (RV) over 4 years, from
7/1/2015 to 6/30/2019 among adults ≥18 years of age for Allegheny County
(Pittsburgh), Pennsylvania. Methods: We used population-based statewide
hospital discharge data, health system electronic medical record (EMR)
data for RV tests, census data, and a published method to calculate
burden. Results: Among 26,211 eligible RV tests, 67.6% were negative
for any virus. The viruses detected were rhinovirus/enterovirus (2,552;
30.1%), influenza A (2,299; 27.1%), RSV (1,082; 12.7%), human
metapneumovirus (832; 9.8%), parainfluenza (601; 7.1%), influenza B
(565; 6.7%), non-SARS-CoV-2 coronavirus (420; 4.9% 1.5 years of data
available), and adenovirus (136; 1.6%). Most tests were among female
(58%) and white (71%) patients with 60% of patients ≥65 years, 24%
50-64 years and 16% 18-49 years. The annual burden, ranged from
137-174/100,000 population for rhinovirus/enterovirus; 99-182/100,000
for influenza A; 56-81/100,000 for RSV. Among adults <65
years, rhinovirus/enterovirus hospitalization burden was higher than
influenza A; whereas the reverse was true for adults ≥65 years. RV
hospitalization burden increased with increasing age. Conclusions: These
virus-specific ARI population-based hospital burden estimates showed
significant non-influenza burden. These estimates can serve as the basis
for several areas of research that are essential for setting funding
priorities and guiding public health policy.
