All URI's declined during COVID
due to non-pharmaceutical interventions to slow down the spread of infection and lessen the burden on health care systems.
https://www.nature.com/articles/s415...utton%20sticky
Abstract |
The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused substantial global morbidity and deaths, leading governments to turn to non-pharmaceutical interventions to slow down the spread of infection and lessen the burden on health care systems.
These policies have evolved over the course of the COVID-19 pandemic, including after the availability of COVID-19 vaccines, with regional and country-level differences in their ongoing use. The COVID-19 pandemic has been associated with changes in respiratory virus infections worldwide, which have differed between virus types.
Reductions in respiratory virus infections, including by influenza virus and respiratory syncytial virus, were most notable at the onset
of the COVID-19 pandemic and continued in varying degrees through subsequent waves of SARS-CoV-2 infections. The decreases in community infection burden have resulted in reduced hospitalizations and deaths associated with non-SARS-CoV-2 respiratory infections.
Respiratory virus evolution relies on the maintaining of a diverse genetic pool, but evidence of genetic bottlenecking brought on by case reduction during the COVID-19 pandemic has resulted in reduced genetic diversity of some respiratory viruses, including influenza virus.
By describing the differences in these changes between viral species across different geographies over the course of the COVID-19 pandemic, we may better understand the complex factors involved
in community co-circulation of respiratory viruses.
...
Conclusions
The COVID-19 pandemic has led to unprecedented societal and human behaviour changes that have altered the community circulation of non-SARS-CoV-2 respiratory viruses.
Although changes in testing priorities and available resources may have influenced the earliest reports of non-SARS-CoV-2 respiratory virus activity, subsequent studies across multiple geographic locations have shown consistent reductions in the activity of most respiratory virus species. However, as the COVID-19 pandemic progressed, there were increasing differences in the application of NPIs and community circulation of SARS-CoV-2 that led to variability in the return of some respiratory viruses.
Most notably, influenza virus activity, including the clinical burden of disease and paediatric mortality, remained low through the 2020-2021 season before influenza virus activity increased in 2021-2022.
While influenza A and influenza B viruses have begun circulating more widely, influenza B/ Yamagata viruses have hardly been detected, and ongoing surveillance will inform whether these viruses might be extinct.
Detections of RSV infections initially remained low, with the resurgence of interseasonal circulation in many locations since 2021.
There is also evidence that influenza virus diversity and RSV diversity have been reduced as a result of the COVID-19 pandemic, but whether these changes are maintained requires continued surveillance and genomic analyses.
Unlike many of the enveloped viruses, non-enveloped viruses, including rhinovirus, demonstrated remarkable persistence through NPIs, with early evidence showing similar species circulation before and during the COVID-19 pandemic. In part, the persistence of non-enveloped viruses despite NPI implementation may be due to prolonged shedding, their greater diversity and their persistence on environmental surfaces.
These collective findings and lessons learned during the COVID-19 pandemic have important implications for pandemic preparedness. Although the changes in circulation of non-SARS-CoV-2 respiratory viruses cannot be attributed to any one factor, the near-simultaneous implementation of NPIs at individual, community, environmental and country levels, in addition to behavioural changes, seems to have been an important contributor to reducing community circulation, decreasing the associated health care burden and blunting the evolution of non-SARS-CoV-2 respiratory viruses. As such, these collective NPI strategies and global collaboration will be important public health considerations for the next pandemic.