Gyakori influenza: ez a vége egy örökké tartó betegségnek?

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  Quantumrun Foresight
• Február 11, 2022

Insight összefoglaló

The shifting patterns of flu seasons and their strains, possibly influenced by measures taken during the COVID-19 pandemic like social distancing, mask-wearing, and increased hygiene practices, has seen a decrease in flu illnesses and a potential extinction of some strains. Additionally, as these changes affect how scientists predict and combat upcoming flu strains, the influenza landscape may alter, resulting in implications across several sectors. These impacts range from improved public health and increased workplace productivity, to a decline in flu vaccine production that may redirect pharmaceutical focus towards more specialized diseases.

The common flu context

Every year, different strains of the flu spread across the world, generally in response to a seasonal pattern of colder and/or drier weather. According to the Centers for Disease Control and Prevention (CDC), the flu season typically peaks between December and February each year, resulting in 45 million illnesses, 810,000 hospitalizations, and 61,000 fatalities. The 2020 pandemic caused by SARS-CoV-2 has infected at least 67 million individuals and killed 1.5 million globally. Towards the end of the first wave of COVID-19 in several countries, health workers observed an early and sudden end to the 2019–20 flu season in the Northern Hemisphere.

Experts believe that this may have been caused by fewer individuals going into healthcare settings for testing alongside effective pandemic-fighting measures such as mask-wearing, social distancing, enhanced hand hygiene, and restricted travel. Positive tests for the flu virus decreased by 98 percent in the US after the COVID pandemic began, while the number of samples submitted for testing reduced by 61 percent. The CDC graded the 2019–20 flu season in the US as "moderate" estimating that 38 million people became ill with influenza, while 22,000 died. 
 
Scientists are hoping that this year's interrupted seasons will provide new insights regarding the transmission and behavior of the flu virus. In 2021, entire populations are continuing to wear masks, wash their hands often, and physically separate themselves, so these precautions may help to keep the flu at bay in 2021 as well. Vaccinations are also contributing to infection prevention. The CDC reports that more Americans have received flu vaccinations this season than in the previous four flu seasons. Almost 193.2 million people had been immunized against the flu in January 2021, compared to just 173.3 million in 2020. 

Bomlasztó hatás 

It has also been hypothesized that a low-flu season may eliminate less common influenza strains. Around the world, scientists track the mutation of flu viruses by examining samples from confirmed flu cases that visit hospitals and doctors' offices. This allows them to forecast the likely batch of common strains that will proliferate the following year and then develop vaccinations to fight against those strains. This procedure is repeated twice a year, considering the Northern and Southern hemispheres. However, no traces of two prevalent flu strains have been identified since March 2020: influenza B viruses from the Yamagata branch and a clade of influenza A H3N2 virus known as 3c3. As a result, it's conceivable, but not certain, that these strains may have gone extinct. 

As life in the US and other highly vaccinated countries eventually returns to normal, the possibility of flu transmission between individuals will return as well. However, the current scenario may make forecasting which strains will drive the next flu season easier because there may be less flu diversity to worry about. If the B/Yamagata lineage is eradicated, future vaccines may only need to defend against three primary strains of the virus, rather than the four-strain strategy now in use. 

Unfortunately, the absence of viral competition in human hosts might potentially pave the way for new swine-flu variants in the future. These viruses are typically hindered by natural immunity. Alternatively, if flu incidence is low for a few seasons, this may allow swine viruses to have a greater impact.

Implications of the common flu evolving

Wider implications of the common flu evolving may include:

• An uptick in overall public health, reducing strain on healthcare systems, freeing up resources for the treatment of other illnesses.
• A decline in seasonal sick leave resulting in increased productivity in workplaces, boosting economic growth.
• The scaling back of flu vaccine production, affecting pharmaceutical companies economically, as a major source of annual revenue vanishes.
• A shift in the pharmaceutical industry towards more specialized or rare diseases as the common flu no longer commands the vast research and development investments.
• Fewer severe flu cases in vulnerable populations contributing to an increased life expectancy.
• The lessened need for flu-related medical supplies leading to a reduction in medical waste, providing environmental benefits through reduced waste generation.

Megfontolandó kérdések

• If the flu can almost be eradicated in 2021, do you think it may be possible to combat the flu more easily in future seasons?
• Which steps do you consider helped the most to halt the spread of flu during the COVID pandemic?