The essay below 
The Conversation, an online publication covering the latest research.
The 2022 cold and flu season has started with a bang. A virus that has been unusually rare over the past three years is re-emerging at very high levels, causing a “triple infection” of COVID-19, influenza and respiratory syncytial virus (RSV). The number of hospitalized patients nationwide due to influenza in November this year was the highest level in 10 years.
We are epidemiologists and researchers of infectious diseases, dedicated to understanding how viruses spread and how best to stop them.
To respond to the COVID-19 pandemic, we and our public health colleagues needed to quickly revive and apply decades of evidence on respiratory virus transmission to chart a course forward. . Over the course of the pandemic, epidemiologists have brought new certainty to the fact that face masks, one of the oldest ways to control respiratory viruses, remain one of the most effective tools in a pandemic. established.
Unlike past waves of COVID-19 since spring 2020, this fall’s surge in respiratory illness is not due to a single new virus. Rather, now that masks and other measures have lost their way, the United States is returning to the classic cold and flu seasonal pattern. and subtypes of the virus lead to ever-changing waves of disease.
Nowhere is this pattern more evident than in young children. Our research shows that classrooms house many viruses at once, and an individual child can be infected with two or three while he is sick with one.
Although only inconvenient for most people, respiratory viruses like seasonal flu can cause them to miss work or school. may be connected. After fighting one virus for years, parents are now exhausted by the reality of fighting more.
But there are simple ways to reduce the risk to yourself and others. When it comes to individual decisions, masks are one of the lowest cost and most effective measures you can take to significantly reduce the transmission of many viruses.
Long before the COVID-19 pandemic, researchers were studying the effectiveness of masks in reducing transmission of other respiratory viruses. From 2002 he found that in his first meta-analysis of viral spread during her SARS epidemic in 2003, he showed that one infection was avoided.
The wearing of masks by health care workers has long been considered a primary strategy for protecting at-risk young infants from RSV infections transmitted in hospital settings. Scientific assessment of mask effectiveness has historically been clouded by the fact that mask wearing is often used in combination with other strategies such as hand washing. The use of personal protective equipment such as masks, gowns, gloves and, in some cases, goggles is commonly associated with reduced transmission of RSV.
Similarly, one of the largest pre-COVID-19 randomized studies of mask wearing, conducted in 2006-2007 in more than 1,000 University of Michigan dormitory students, found that respiratory disease symptoms in mask wearers was found to be reduced. This was especially true when masks were combined with hand hygiene.
Recently, researchers measured the amount of virus present in the breath of people with respiratory symptoms to study how well masks blocked the release of viral particles. Those who were randomly selected to wear masks had lower levels of respiratory shedding of influenza, rhinovirus (which causes the common cold), and non-SARS coronaviruses compared to those who did not wear masks.
Three years after the pandemic, the evidence and experience with masks has grown significantly. Laboratory studies and outbreak investigations have shown that masks reduce the amount of virus entering the air and reduce the amount of virus entering the respiratory tract when breathing. wearing a surgical mask has been shown to reduce the chance of testing positive for COVID-19 by 66%, and wearing an N95/KN95 type mask has been shown to reduce the chance of testing positive by 83%.
When school children wear masks, infection decreases
Our own research shows the significant impact of mask wearing on transmission of SARS-CoV-2, the virus that causes COVID-19, and other viruses. We found that school-wide mask requirements were associated with a reduction in his COVID-19 infection while the highly contagious Delta variant was in circulation in the fall of 2021. School-age children living in non-mask-requiring districts had a faster rate of infection in the first few weeks of the school year than children in full or partial mask-requiring districts. A similar pattern has emerged in other states, coinciding with the lifting of school mask requirements in the spring of 2022.
A preliminary study in a frequent mask-wearing community found that the rate of non-COVID respiratory illness in families decreased by 50% between 2020 and 2021 compared to previous years. Our study found that the virus currently ravaging the United States began a resurgence as participants reported easing mask-wearing and other mitigating actions in early 2022. It started with the re-emergence of two “cold” seasonal coronaviruses.
Unfortunately, vaccines are only available for two of the leading causes of respiratory disease: SARS-CoV-2 and influenza. Similarly, antiviral treatments are more commonly available for SARS-CoV-2 and influenza than for RSV. After years of development, an RSV vaccine is expected to become available soon, but not in time to stem the current wave of disease.
In contrast, masks can reduce transmission of all respiratory viruses and interventions need not be tailored to the specific virus circulating. continues to be a low-cost, low-tech way to spend precious time with family and friends free from illness.
This article originally appeared on The Conversation. Please read the original article.
