Monitoring Report: Respiratory Viruses - November 2024 Data

BackgroundFew sources regularly monitor hospitalizations associated with respiratory viruses. This study provides current hospitalization trends associated with six common respiratory viruses: COVID-19, influenza, human metapneumovirus (HMPV), parainfluenza virus, respiratory syncytial virus (RSV), and rhinovirus. ObjectiveThis study aims to supplement the surveillance data provided by the CDC by describing latest trends (through March 01, 2026) overall and for each respiratory virus. This study also provides valuable insight into two at-risk populations: infants and children (age 0-4) and older adults (age 65 and over). MethodsUsing a subset of real-world electronic health record (EHR) data from Truveta, a growing collective of health systems that provides more than 18% of all daily clinical care in the US, we identified people who were hospitalized between October 01, 2020 and March 01, 2026. We identified people who tested positive for any of the six respiratory viruses within 14 days of the hospitalization. We report weekly trends in the rate of hospitalizations associated with each virus per all hospitalizations for the overall population and the two high-risk sub populations: infants and children and older adults. ResultsWe included 1,029,468 hospitalizations of 904,312 unique patients who tested positive for a respiratory virus between October 01, 2020 and March 01, 2026. Overall, respiratory virus-associated hospitalizations declined slightly throughout February 2026. By the last week of the month, respiratory virus hospitalizations accounted for 3.6% of all hospitalizations, down from 4.3% at the end of January (-15.3%). This decline was primarily driven by influenza and COVID (-34.2% and -16.0%), while RSV, rhinovirus, HMPV-, and parainfluenza-associated hospitalizations all remained relatively low and stable across the month. Among children aged 0-4 years, respiratory virus-associated hospitalizations increased slightly across February, and accounted for 4.3% of hospitalizations by the end of the month (+11.8%). This increase was primarily driven by HMPV, with HMPV-associated hospitalizations more than doubling throughout February (+111.7%), while RSV-, rhinovirus-, influenza-, COVID- and parainfluenza-associated hospitalizations remained stable (+7.6%, +5.4%, 7.5%, +17.9%, +91.6%). Among adults aged 65 years and older, respiratory virus-associated hospitalizations declined modestly, decreasing from 5.3% to 4.4% of all hospitalizations (-17.0%). This decline was primarily driven by reductions in influenza- and COVID-associated hospitalizations, while RSV-associated hospitalizations increased slightly, and other viruses remained low and stable. Discussion: Respiratory virus-associated hospitalizations declined slightly during February 2026, reflecting a seasonal decrease in respiratory virus activity. Overall, influenza remained the largest contributor to respiratory virus-associated hospitalizations despite declining hospitalization rates. Among children aged 0-4 years, hospitalization rates remained increased slightly, with RSV continuing to represent the largest share of respiratory virus-associated hospitalizations and HMPV-associated hospitalizations more than doubling over the last month. In contrast, older adults experienced modest declines in respiratory virus-associated hospitalizations, driven primarily by decreases in influenza- and COVID-associated hospitalizations. Together, these findings suggest a gradual seasonal decline in respiratory virus burden across the overall population--particularly among older adults. However, RSV, rhinovirus, influenza, and HMPV continue to contribute to hospitalizations in the pediatric population. Trends in surveillanceO_ST_ABSOverall populationC_ST_ABS O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=108 SRC="FIGDIR/small/24317745v10_ufig1.gif" ALT="Figure 1"> O_LINKSMALLFIG WIDTH=200 HEIGHT=108 SRC="FIGDIR/small/24317745v10_ufig1a.gif" ALT="Figure 1"> View larger version (60K): org.highwire.dtl.DTLVardef@bccadeorg.highwire.dtl.DTLVardef@aadc2dorg.highwire.dtl.DTLVardef@15d4f53org.highwire.dtl.DTLVardef@102d3de_HPS_FORMAT_FIGEXP M_FIG C_FIG At the end of February 2026, respiratory virus-associated hospitalizations accounted for 3.6% of all hospitalizations, a slight decrease from the end of January 2026 (4.3%, - 15.3%). Influenza-associated hospitalizations decreased from 2.1% to 1.4% of all hospitalizations (-34.2%) and COVID-associated hospitalizations decreased slightly from 0.8% to 0.6% of all hospitalizations (-16.0%). RSV, rhinovirus, HMPV-, and parainfluenza-associated hospitalizations all remained relatively low and stable across the month. Influenza, COVID, and parainfluenza test positivity decreased slightly (-14.3%, -13.5%, - 15.6%, respectively), while rhinovirus, RSV, and HMPV test positivity increased slightly (+11.8%, +9.2%, +64.1%, respectively). The overall findings suggest a slight seasonal decline. Although influenza-associated hospitalizations declined, influenza still accounted for the largest proportion of respiratory virus-associated hospitalizations. Infants and children (age 0-4) O_FIG O_LINKSMALLFIG WIDTH=174 HEIGHT=200 SRC="FIGDIR/small/24317745v10_ufig2.gif" ALT="Figure 2"> View larger version (42K): org.highwire.dtl.DTLVardef@a3c69aorg.highwire.dtl.DTLVardef@43d0cborg.highwire.dtl.DTLVardef@40f1d3org.highwire.dtl.DTLVardef@1c47dd5_HPS_FORMAT_FIGEXP M_FIG C_FIG In the population aged 0-4 years, respiratory virus-associated hospitalizations increased slightly throughout February and are now at a rate of 4.3% of all hospitalizations in this age group (+11.8%). This increase was primarily driven by HMPV, with HMPV-associated hospitalizations more than doubling throughout February (+111.7%). RSV-, rhinovirus-, influenza-, COVID- and parainfluenza-associated hospitalizations remained stable (+7.6%, +5.4%, 7.5%, +17.9%, +91.6%). RSV-associated hospitalizations accounted for 2.1% of all hospitalizations by the end of the month, representing the largest share of respiratory-virus associated hospitalizations in this age group. In this pediatric population, rhinovirus and RSV test positivity remained stable (+8.8% and -2.1%, respectively), influenza, COIVD, and parainfluenza test positivity decreased slightly (-21.4%, -15.2%, -13.1%, respectively), and HMPV test positivity increased (+46.8%). Together, these patterns suggest that HMPV drove the increase in respiratory virus activity among children aged 0-4 years, while activity for other viruses remained relatively stable. Older adults (age 65 and over) O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/24317745v10_ufig3.gif" ALT="Figure 3"> O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/24317745v10_ufig3a.gif" ALT="Figure 3"> View larger version (52K): org.highwire.dtl.DTLVardef@1213e52org.highwire.dtl.DTLVardef@1827d26org.highwire.dtl.DTLVardef@1e655d8org.highwire.dtl.DTLVardef@10e1567_HPS_FORMAT_FIGEXP M_FIG C_FIG Among adults aged 65 years and older, respiratory virus-associated hospitalizations accounted for 4.4% of all hospitalizations, a slight decrease from the end of January 2026 (5.3%, -17.0%). Influenza- and COVID-associated hospitalizations declined in February (-38.3% and -18.7%, respectively), while RSV-associated hospitalizations increased (+22.6%). HMPV, rhinovirus, and parainfluenza remained low and stable across the month. In this older adult population, influenza and parainfluenza test positivity decreased (-31.2% and -32.6%, respectively), while rhinovirus, RSV, and HMPV test positivity increased (+15.1%, +24.4%, +61.5%). COVID test positivity remained stable across the month (+0.0%). Overall, these findings indicate a slight decrease in respiratory virus-associated hospitalizations among older adults in February, driven primarily by declines in influenza- and COVID-associated hospitalizations.