Based on the period of COVID-19 NPIs in effect in China, the researchers examined the epidemiology and seasonal trends of influenza.
Influenza activity significantly decreased, indicating that the COVID-19-related actions were successful in halting the spread of other viral respiratory infections. According to a study, ongoing public health initiatives in China to combat COVID-19 may be linked to a decline in influenza prevalence.
The COVID-19 epidemic led to the unprecedented global adoption of extensive public health initiatives. During the epidemic worldwide reports of seasonal virus detection have dropped sharply. There is little available data on the effect of pediatric influenza-related hospitalizations.
Preliminary evidence of the long-term association between preventive and control strategies and influenza transmission in China during the COVID-19 pandemic is provided by the study, which was published in the journal Health Data Science.
Method: Motif, setting, and data frame
The Canadian Immunization Monitoring Program, ACTive, provided information on hospitalizations, ICU admissions, and in-hospital mortality due to influenza in children across Canada. 90% of all pediatric tertiary care beds in Canada are part of this nationwide active surveillance project. The eleven influenza seasons from the 2010–2011 season to the 2020–2021 season comprised the research period. After the COVID-19 pandemic, time series modeling was performed to compare the observed and expected hospitalizations for it.
Research Findings
Zirui Guo from the Peking University School of Public Health stated that from December 2019, different nonpharmaceutical interventions (NPIs) including the COVID-19 vaccine have been employed to prevent and control the community spread of COVID-19. Guo noted that it was unclear how the evolving influenza outbreak related to COVID-19 prevention and control.
A major seasonal epidemic or possibly a pandemic can result from acute respiratory infectious illness. But in early 2020, the researchers noted a noticeable decline in the US, Japan, and other parts of the Northern Hemisphere. During their peak season in 2020, Australia, Chile, and other countries in the Southern Hemisphere also reported this observation.
Influenza, Epidemiological Pattern In COVID Era
Professor Min Liu stated that the COVID-19 outbreak “changed the epidemiological pattern and features of influenza”. During the 2020–2022 COVID–19 pandemic, a considerable decline in its activity was seen in China, notably in the winter and spring.
Furthermore, seasonality was present in China’s north and south from 2010 to 2019 but was not present during the 2020–2021 season. Based on the period of COVID-19 NPIs in effect in China, the researchers examined the epidemiology and seasonal trends of it.
They discovered that regular COVID-19 public health initiatives throughout the nation may be linked to a decline in virus infection. In the winter and spring, when COVID-19 and influenza tend to spread rapidly, respiratory infections are more common.
According to the researchers, the comeback of other respiratory viruses that had been controlled by COVID-19 NPIs in 2020–2021 was widely acknowledged. Following a lengthy low flu season in 2020–2022, they said that everyone has lost the chance to develop stronger protection against influenza.
They also added that as time passes, high-risk groups, such as children and the elderly, become more susceptible to widespread and serious infection. Along with improving influenza vaccination coverage, they recommended strengthening surveillance and establishing an extensive surveillance system for both the influenza virus and SARS-CoV-2 in order to safeguard these susceptible groups.
Given the limitations of our analysis, Liu recommended conducting further research to support the findings. The study remarked, “Additional factors, such as the percentage of patients that tested positive for influenza and the number of reported cases, may reinforce and validate the findings”.
