Global Epidemiology and Disease Burden of Human Parainfluenza Virus in Adults: A Systematic Review

Abstract

Parainfluenza virus (PIV) is a common cause of respiratory illness in children and immunocompromised adults, but little is known about its epidemiology or disease burden in the general adult population. This review evaluates published global epidemiological and disease burden for PIV in adults, including high-risk patients (immunocompromised or with chronic illnesses), and identifies existing data gaps. A PRISMA systematic review of publications from 2014 to 2023 in PubMed reporting PIV prevalence and disease burden (including hospitalisations, mortality) in adults (≥ 18 years) and high-risk patients was performed. Sixty-five studies were included; which skewed towards Asia, Europe, and North America, highlighting a data gap in global PIV prevalence. Overall prevalence of PIV (all strains) ranged from 0 to 15.2% [median 2%] in the general adult population (not considered high-risk but tested for infection). PIV3 was the most prevalent strain (0.6-15.2% [2.9]), followed by PIV4 (0.4-6.5% [1.9]), PIV1 (0.5-2.8% [1.1]), and PIV2 (0-2.9% [1.1]). PIV prevalence was generally higher in high-risk adults (up to 41% in certain risk groups) and those aged ≥ 65. Mortality rates ranged from 2 to 40% in those high-risk, while need for respiratory assistance ranged from 0.9% to 64.2% and hospitalisation from 3.7% to 45.3%. None of the studies reported cost-related healthcare resource utilisation. Variability of study designs, data stratification, and patient populations in the selected studies challenged evaluating the true prevalence of PIV and its burden. PIV infection carries an underappreciated burden, with substantial morbidity and mortality risks, especially in high-risk patients. Significant knowledge gaps exist regarding global prevalence and economic burden in the general adult population.

Keywords: PIV; burden; parainfluenza virus; prevalence; respiratory illness.

FIGURE 1

Published regional prevalence of PIV. Prevalence of PIV reported in previously published studies (2014−2023) is plotted by broad geographic region (North America, [18, 45, 59, 68, 76, 79] South America, [19, 69] EU/UK, [16, 17, 29, 48, 60, 62, 66] Middle East, [15, 47] Asia, [20, 21, 38, 44, 50, 52, 72, 73, 74, 75, 80] South Asia, [42, 58, 67] and Australia [14]). Prevalence was defined as the percentage of detected PIV infections (any strain) out of all samples tested from the respective population, inclusive of hospitalised adults, surveillance data, or those already testing positive for a respiratory virus. In some cases, prevalence rates included here were manually calculated or pooled across multiple age groups from statistical data reported in the published sample set. N denotes the number of studies contributing to the listed range of PIV prevalence, by region. Countries with data available are colour coded and scaled from light to dark blue based on the highest prevalence reported for that region for any strain of PIV (see inset on bottom left). Countries lacking data are coded in white. *Upper limit includes prevalence calculated based on reported rates for PIV4a and PIV4b combined. EU, European Union; PIV, parainfluenza virus; UK, United Kingdom.

FIGURE 2

Published regional positivity rate of PIV subtypes out of total PIV infections. Rate of positive PIV‐subtype specific infections out of all tested PIV infections reported in previously published studies (2014−2023) are plotted by broad geographic region (North America, [3, 18, 55, 70] South America, [19] EU/UK, [16, 17, 23, 24, 54] Middle East, [15] Asia, [20, 21, 22, 37, 40, 53, 57] and Australia [14]). Subtype rates were manually calculated or pooled across multiple age groups from statistical data reported in the published sample set where available, if not explicitly reported in the literature. Only 10 studies included in the reference set reported rates for all 4 PIV subtypes; thus, the figure above includes data from references reporting rates for only some of the PIV subtypes (see Supporting Information S1: Table S3). N denotes the number of studies contributing to the listed range of PIV subtype rates, by region. Countries with data available are colour coded blue, with countries lacking data within the sample set coded in white. The highest reported rate for each strain is colour coded and scaled light to dark blue per region (see inset on bottom left), with PIV3 being the most commonly detected PIV infection subtype in most regions, with the exception of Asia, where PIV3 and PIV4 were reported at similar peak detection rates. *Range includes one study reporting specific rates for PIV4a and PIV4b (see Supporting Information S1: Table S3). EU, European Union; PIV, parainfluenza virus; UK, United Kingdom.

FIGURE 3

Published regional burden of PIV infection (mortality, need for oxygen, and hospitalisation/ICU admission rate). Rate of previously published (2014−2023) patient burden outcomes including mortality rates, need for oxygen or mechanical ventilation, and hospitalisation or ICU admission rates are plotted by broad geographic region (North America, [3, 25, 28, 79] EU, [23, 24, 26, 27, 29, 36] Middle East, [15] Asia, [22, 32, 34, 35, 37, 43] and Australia [31]). N denotes the number of studies contributing to the listed range of reported patient outcomes, by region. Countries with data available are colour coded blue, with countries lacking data within the sample set coded in white. Burden data across patient outcomes were limited in most parts of the world. EU, European Union; ICU, intensive care unit; PIV, parainfluenza virus.