In March 2020, the world’s top countries implemented non-pharmaceutical interventions (INPs), adding the use of masks, social estating, school closures and telework to prevent the spread of Covid-19. these interventions have curbed the Covid-19 pandemic, but we now know that they have helped curb the spread of influenza.
Ideally, the effectiveness of an intervention (e. g. dressing with a mask) is measured by examining the effects being attempted (for example, the number of Cases of Covid-19). With seasonal diseases like influenza, the ability to compare the existing year with past years makes it easier, but with Covid-19, we have no comparison history. It is also difficult to evaluate the effectiveness of interventions in Covid-19 through other means due to the variable availability of tests, the lack of design and the evolution of the criteria to receive a test. For example, some deniers have argued that NMNs have little epidemiological impact.
But since influenza, like Covid-19, is a respiratory disease, it is moderate to assume that covid-19 interventions also deserve the spread of influenza, and if we see Covid-19 NPI running on influenza, we deserve to infer that they also paint to some extent in Covid-19. In addition, a new study published in the CDC’s Weekly Morbidity and Mortality Report (MMWR) examines the data between national responses to Covid-19 and the decrease in influenza cases in the United States and 3 southern hemisphere countries.
In the United States, there is a transparent difference in the trajectory of this year’s flu season, scheduled until the arrival of the Covid-19.
First, the 2020 summer flu is gone. Although little known, other people can “get the flu” at any time of the year, not just in winter. The intensity of influenza transmission is measured by the positivity rate, the fraction of respiratory infections that tested the flu positive. In the U. S. summer, flu positivity tends to be around 1% or 2%, while in 2017 it was 2. 36%. In 2018, it was 1. 04%. In 2019 it was 2. 35% and in the first summer with Covid-19 it was reduced from five to ten times to 0. 20%.
Second, covid-19’s arrival in the United States (marked through the president’s statement of a national state of emergency) coincided with the decline of the same old winter flu season. Comparing the rate at which the 2020 flu seasons ended “compared to other years, the authors were going to have a concept of how NPI cuts off flu transmission. While peak flu seasons are gradually ending, the 2020 season has come to an early end. If we count the “end” of the season flu as the time when the positivity rate drops to its overall interstellar point around 2%, it turns out that the 2020 flu season ended at most two months earlier.
Finally, the authors analyzed influenza in 3 countries, Australia, Chile and South Africa, in the southern hemisphere, which is vital because winter in the southern hemisphere corresponds to summer in the northern hemisphere. The flu in the southern hemisphere is expected to heat up, but this is not what happened in 2020. This year, the flu almost undetectable in the Southern Hemisphere with Australia, Chile and South Africa reporting a total of only 51 positive samples from 83307 samples analyzed for an unheard of positivity rate of 0. 06%. By comparison, the average positivity in 2017-2019 in those countries 13. 7%, meaning that influenza cases in the southern hemisphere decreased by more than 99%.
The result of these analyses is that multinationals followed to mitigate the spread of Covid-19 are almost also guilty of drastic discounts on influenza transmission and, because they decrease influenza transmission, they are likely to also decrease Covid-19 transmission.
The exam also highlights knowledge that will be of interest to other people after the Covid-19 pandemic who may want to compare it to the flu. The exam used two other sets of knowledge. The knowledge of the US comes from a large number of diagnostic laboratories that are under the WHO Collaborating Laboratory System or the National Surveillance System for Enteric and Respiratory Viruses. Data for Australia, Chile, and South Africa are from the Global Influenza Surveillance and Response System. All knowledge used in the exam is open access, which means it is in the public domain, provided through public agencies to scientists and laymen alike. Data for the United States can be downloaded from CDC’s FluView platform. Data for Australia, Chile and South Africa can be received from the FluNet system of the World Health Organization. Both websites provide interactive teams for anyone and explore the knowledge that they find interesting. Just as hobby astronomers have discovered exoplanets, I bet there are epidemiological patterns waiting to be discovered by anyone with the interest, imagination, and diligence to study them.
I’m a pinté scientist at the University of Georgia, where I’m a professor at the Odum School of Ecology and director of the Center for Infectious Disease Ecology. I fell in love with nature as a child and theoretical biology when I was a young adult. My studies use mathematics, statistics, pc models and experiments to perceive the dynamics of biological populations. I’m interested in ecological turning points, the ecology of emerging infectious diseases and extinction. My purpose is to make science that fears people, earth and the planet.