Impact of Social Distancing and Travel Restrictions on non-COVID-19 Respiratory Hospital Admissions in Young Children in Rural Alaska

Abstract Hospitalizations due to non-COVID-19 respiratory illnesses decreased dramatically after social distancing was implemented in a high-risk population in rural Alaska. Our data from the past ten respiratory seasons show that this decline is unprecedented. This demonstrates the potential secondary benefits of implementing social distancing and travel restrictions on respiratory illnesses.

A c c e p t e d M a n u s c r i p t 3

Background
Social distancing was implemented in many regions in the spring of 2020 to limit the spread of SARS-CoV-2, the virus responsible for coronavirus disease 2019 (COVID-19). Many reports have compared the respiratory illness rates during social distancing to one or two previous seasons; however, it is important to evaluate the difference over multiple seasons due to year to year variations in influenza, respiratory syncytial virus (RSV), and other respiratory illnesses [1][2][3]. People in the remote Yukon-Kuskokwim Delta (YKD) region of Alaska have a high burden of respiratory illnesses, with up to ten times the rate of infant hospitalization for pneumonia compared to the general US population [4] and the highest reported rates of infant RSV hospitalization in the United States, reaching 259 per 1,000 infants [5]. All YKD residents who require hospitalization go through the YKD Regional Hospital (YKDRH), allowing detection of all hospitalizations in this population. Our team has conducted passive surveillance for RSV and acute respiratory infection (ARI) hospitalizations in YKD children under 3 years of age since 1996 [6].
Three social distancing mandates were issued by the Governor of Alaska in the spring of 2020. The first, on March 20 th , closed all schools, the second, on March 27 th , limited intrastate travel and travel to small communities, and the third, on March 28 th , closed nonessential businesses, prohibited public gatherings, and required people stay 6 feet apart from non-household members. These mandates limited both the transmission of pathogens within the YKD and the introduction of pathogens from outside regions.
At that time, no cases of SARS-CoV-2 were documented within the YKD and there was no evidence it was circulating in this population. We compared the total, ARI, and RSV hospitalization rate in YKD children <3 years in the first 5 months of 2020 to the previous ten respiratory illness seasons.   One limitation of our study is the inability to distinguish what proportion of the decline in ARI hospitalizations in YKD children is due to avoidance of care versus a decrease in circulation of respiratory pathogens secondary to the health mandates. Numerous reports show people avoided medical care for a range of conditions during the peak months of the pandemic, resulting in in-home deaths and delayed diagnoses [7][8][9]. We hypothesize that if the precipitous decline was due only to avoidance of care, there would have been an increased number of children presenting late to care, leading to an increase in critically ill children and deaths due to ARI. Instead, only one child was hospitalized with respiratory failure and no respiratory related deaths were recorded in April or May. Because of the lack of severe respiratory outcomes in this population, we conclude that the observed decline was primarily driven by the reduction in pathogen circulation due to travel restrictions and social distancing.
Our data show a large amount of variability in ARI admissions year to year, therefore comparing the 2019-2020 season to one or two other seasons, as done in other publications, may be misleading. Here we compare the 2019-2020 season to the ten preceding seasons and show a precipitous and sustained decline in ARI admissions related to the start of social distancing mandates.
These data compare ARI hospital admissions during the recent 2019-2020 season with ten preceding seasons in a unique population in rural Alaska with a history of very high rates of respiratory hospitalizations and limited medical accessibility. Due to its extreme isolation, all children receive care from a single health center or are transferred by small