The burden of influenza in the United States can vary from year to year depending on which viruses are circulating, how many people receive an influenza vaccination, and how effective the vaccination is in that particular year. During the 2023-2024 flu season, around 28,000 people lost their lives to the disease. Although most people recover from influenza without needing medical care, the disease can be deadly among young children, the elderly, and those with weakened immune systems or chronic illnesses. Deaths due to influenza Even though most people recover from influenza without medical care, influenza and pneumonia can be deadly, especially for older people and those with certain preexisting conditions. Influenza is a common cause of pneumonia and although most cases of influenza do not develop into pneumonia, those that do are often more severe and more deadly. Deaths due to influenza are most common among the elderly, with a mortality rate of around 32 per 100,000 population during the 2023-2024 flu season. In comparison, the mortality rate for those aged 50 to 64 years was 9.1 per 100,000 population. Flu vaccinations The most effective way to prevent influenza is to receive an annual influenza vaccination. These vaccines have proven to be safe and are usually cheap and easily accessible. Nevertheless, every year a large share of the population in the United States still fails to get vaccinated against influenza. For example, in the 2022-2023 flu season, only 35 percent of those aged 18 to 49 years received a flu vaccination. Unsurprisingly, children and the elderly are the most likely to get vaccinated. It is estimated that during the 2022-2023 flu season, vaccinations prevented over 929 thousand influenza cases among children aged 6 months to 4 years.

The mortality rate from influenza in the United States is by far highest among those aged 65 years and older. During the 2023-2024 flu season, the mortality rate from influenza for this age group was around 32.1 per 100,000 population. The burden of influenza The impact of influenza in the U.S. varies from season to season, but in the 2023-2024 flu season, there were an estimated 40 million cases. These cases resulted in around 470,000 hospitalizations. Although most people recover from influenza without requiring medical treatment, the disease can be deadly for young children, the elderly, and those with weakened immune systems or chronic illnesses. During the 2023-2024 flu season, around 28,000 people in the U.S. lost their lives due to influenza. Impact of vaccinations The most effective way to prevent influenza is to receive an annual vaccination at the beginning of flu season. Flu vaccines are safe and can greatly reduce the burden of the disease. During the 2022-2023 flu season, vaccinations prevented around 2,479 deaths among those aged 65 years and older. Although flu vaccines are usually cheap and easily accessible, every year a large share of the population in the U.S. still does not get vaccinated. For example, during the 2022-2023 flu season, only about 35 percent of those aged 18 to 49 years received a flu vaccination.

Australia Influenza Mortality jumped by 8% in 2019, from a year earlier.

this graph was created in OurDataWorld, R , Loocker and Tableau

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Introduction: Seasonal influenza, often perceived as a common illness, carries a significant global burden, claiming hundreds of thousands of lives annually. Despite advancements in healthcare and vaccination efforts, the flu remains a formidable threat, particularly affecting vulnerable populations such as infants and the elderly. This article delves into the intricacies of influenza-related mortality, examining regional disparities, contributing factors, and the implications for public health.

The Global Landscape of Influenza Mortality: Data from the Global Pandemic Mortality Project II sheds light on the magnitude of influenza-related deaths, drawing from surveillance metrics spanning from 2002 to 2011. These estimates, while informative, underscore the challenge of accurately gauging mortality rates, especially in low-income countries where testing and mortality records may be lacking.

Respiratory Symptoms and Beyond: The conventional understanding of influenza-related fatalities primarily revolves around respiratory complications. Pneumonia and other respiratory ailments serve as prominent causes of death, contributing to the staggering toll of 400,000 lives claimed annually. However, it is imperative to acknowledge that the impact of influenza extends beyond respiratory symptoms. Complications such as strokes and heart attacks, though not explicitly captured in mortality estimates, further amplify the disease's lethality, warranting comprehensive preventive measures.

Vulnerability Across Age Groups: Influenza's lethality is not uniform across age demographics. Infants and the elderly emerge as the most susceptible cohorts, bearing the brunt of severe complications and mortality. Among individuals aged over 65, the mortality rate stands at approximately 31 per 100,000 in Europe alone, reflecting the disproportionate impact on older populations. The interplay of age-related factors, including weakened immune responses and underlying health conditions, exacerbates the severity of influenza outcomes among these groups.

Regional Disparities and Determinants: A notable aspect of influenza mortality lies in its disparate distribution across regions. While Europe and North America exhibit relatively lower death rates, countries in South America, Africa, and South Asia grapple with higher mortality burdens. This regional divide underscores the complex interplay of socio-economic factors, healthcare accessibility, and vaccination coverage. Poverty, inadequate healthcare infrastructure, and suboptimal vaccination rates converge to heighten vulnerability to influenza-related complications, amplifying mortality rates in resource-constrained settings.

Implications for Public Health: The revelation of significant regional differentials in influenza mortality necessitates a tailored approach to public health interventions. Strengthening healthcare systems, particularly in low-income regions, is paramount to bolstering surveillance, enhancing diagnostic capabilities, and facilitating timely interventions. Furthermore, targeted vaccination campaigns, coupled with education initiatives, hold promise in mitigating influenza's toll, especially among vulnerable populations. Addressing socio-economic disparities and bolstering healthcare resilience emerge as pivotal strategies in fortifying global defenses against seasonal influenza.

Conclusion: Seasonal influenza, often underestimated in its impact, exacts a substantial toll on global health each year. The multifaceted nature of influenza-related mortality underscores the need for a nuanced understanding and comprehensive mitigation strategies. By addressing regional disparities, prioritizing vulnerable populations, and fortifying healthcare systems, the global community can strive towards mitigating the burden of seasonal influenza, safeguarding lives, and fostering resilient health systems for generations to come.

Over 12 million people in the United States died from all causes between the beginning of January 2020 and August 21, 2023. Over 1.1 million of those deaths were with confirmed or presumed COVID-19.

Vaccine rollout in the United States Finding a safe and effective COVID-19 vaccine was an urgent health priority since the very start of the pandemic. In the United States, the first two vaccines were authorized and recommended for use in December 2020. One has been developed by Massachusetts-based biotech company Moderna, and the number of Moderna COVID-19 vaccines administered in the U.S. was over 250 million. Moderna has also said that its vaccine is effective against the coronavirus variants first identified in the UK and South Africa.

Influenza, also called the flu, is one of the most infectious diseases worldwide. Its symptoms range from mild to severe, and include sore throat, cough, runny nose, fever, headache, and muscle pain, but can also cause severe illness and death among high-risk populations such as the elderly and children. During the 2023-2024 flu season, there were 40 million cases of influenza in the United States. Influenza deaths Although influenza does not require medical attention for most people, it can be deadly, and causes thousands of deaths every year. The impact of influenza varies from year to year. The number of influenza deaths during the 2023-2024 flu season was 27,965. The vast majority of deaths attributed to influenza during the 2023-2024 flu season occurred among those aged 65 years and older. Vaccination An annual influenza vaccination remains the most effective way of preventing influenza. During the 2022-2023 flu season, influenza vaccinations prevented an estimated 2,479 deaths among U.S. adults aged 65 years and older. Although, flu vaccinations are accessible and cheap, a large share of the United States population still fails to get vaccinated every year. In 2022-2023, only 35 percent of those aged 18 to 49 years received a flu vaccination, much lower compared to children and the elderly.

Global Influenza Mortality Share by Country (Units (Male Deaths)), 2023 Discover more data with ReportLinker!

The flu is estimated to cause 400,000 respiratory deaths each year on average across the world. These deaths come from pneumonia and other respiratory symptoms caused by the flu. People also die from other complications of the flu – such as a stroke or heart attack – but global estimates have not been made of their death toll. The Spanish flu caused the largest influenza pandemic in history. Yet, data on the flu is limited. With better testing, countries could improve their response to flu epidemics. It could help to rapidly identify new strains, detect epidemics early, and design better-matched vaccines to target flu strains circulating in the population.

this data set contains the vaccine coverage around the world from 2018 to 2022.

Global Influenza Mortality by Country, 2023 Discover more data with ReportLinker!

WHO: Influenza A (H1N1): Number of Deaths: Japan data was reported at 0.000 Person in 06 Jul 2009. This stayed constant from the previous number of 0.000 Person for 05 Jul 2009. WHO: Influenza A (H1N1): Number of Deaths: Japan data is updated daily, averaging 0.000 Person from Apr 2009 (Median) to 06 Jul 2009, with 74 observations. The data reached an all-time high of 0.000 Person in 06 Jul 2009 and a record low of 0.000 Person in 06 Jul 2009. WHO: Influenza A (H1N1): Number of Deaths: Japan data remains active status in CEIC and is reported by World Health Organization. The data is categorized under High Frequency Database’s Disease Outbreaks – Table WHO.D002: World Heath Organization: Influenza A (H1N1): By Countries.

Influenza and pneumonia caused around 10.9 deaths in the U.S. per 100,000 population in 2023. Influenza, or the flu, is a viral infection that is highly contagious and especially common in the winter season. Influenza is a common cause of pneumonia, although most cases of the flu do not develop into pneumonia. Pneumonia is an infection or inflammation of the lungs and is particularly deadly among young children and the elderly. Influenza cases Influenza is very common in the United States, with an estimated 40 million cases reported in 2023-2024. Common symptoms of the flu include cough, fever, runny or stuffy nose, sore throat and headache. Symptoms can be mild but can also be severe enough to require medical attention. In 2023-2024, there were around 18 million influenza-related medical visits in the United States. Prevention To prevent contracting the flu, people can take everyday precautions such as regularly washing their hands and avoiding those who are sick, but the best way to prevent the flu is by receiving the flu vaccination every year. Receiving a flu vaccination is especially important for young children and the elderly, as they are most susceptible to flu complications and associated death. In 2024, around 70 percent of those aged 65 years and older received a flu vaccine, while only 33 percent of those aged 18 to 49 years had done so.

WHO: Influenza A (H1N1): Number of Deaths: Australia data was reported at 10.000 Person in 06 Jul 2009. This records an increase from the previous number of 9.000 Person for 05 Jul 2009. WHO: Influenza A (H1N1): Number of Deaths: Australia data is updated daily, averaging 0.000 Person from Apr 2009 (Median) to 06 Jul 2009, with 74 observations. The data reached an all-time high of 10.000 Person in 06 Jul 2009 and a record low of 0.000 Person in 21 Jun 2009. WHO: Influenza A (H1N1): Number of Deaths: Australia data remains active status in CEIC and is reported by World Health Organization. The data is categorized under High Frequency Database’s Disease Outbreaks – Table WHO.D002: World Heath Organization: Influenza A (H1N1): By Countries.

Project Tycho datasets contain case counts for reported disease conditions for countries around the world. The Project Tycho data curation team extracts these case counts from various reputable sources, typically from national or international health authorities, such as the US Centers for Disease Control or the World Health Organization. These original data sources include both open- and restricted-access sources. For restricted-access sources, the Project Tycho team has obtained permission for redistribution from data contributors. All datasets contain case count data that are identical to counts published in the original source and no counts have been modified in any way by the Project Tycho team. The Project Tycho team has pre-processed datasets by adding new variables, such as standard disease and location identifiers, that improve data interpretabilty. We also formatted the data into a standard data format.

Each Project Tycho dataset contains case counts for a specific condition (e.g. measles) and for a specific country (e.g. The United States). Case counts are reported per time interval. In addition to case counts, datsets include information about these counts (attributes), such as the location, age group, subpopulation, diagnostic certainty, place of aquisition, and the source from which we extracted case counts. One dataset can include many series of case count time intervals, such as "US measles cases as reported by CDC", or "US measles cases reported by WHO", or "US measles cases that originated abroad", etc.

Depending on the intended use of a dataset, we recommend a few data processing steps before analysis:

• Analyze missing data: Project Tycho datasets do not inlcude time intervals for which no case count was reported (for many datasets, time series of case counts are incomplete, due to incompleteness of source documents) and users will need to add time intervals for which no count value is available. Project Tycho datasets do include time intervals for which a case count value of zero was reported.
• Separate cumulative from non-cumulative time interval series. Case count time series in Project Tycho datasets can be "cumulative" or "fixed-intervals". Cumulative case count time series consist of overlapping case count intervals starting on the same date, but ending on different dates. For example, each interval in a cumulative count time series can start on January 1st, but end on January 7th, 14th, 21st, etc. It is common practice among public health agencies to report cases for cumulative time intervals. Case count series with fixed time intervals consist of mutually exxclusive time intervals that all start and end on different dates and all have identical length (day, week, month, year). Given the different nature of these two types of case count data, we indicated this with an attribute for each count value, named "PartOfCumulativeCountSeries".

BackgroundWe assessed the severity of the 2009 influenza pandemic by comparing pandemic mortality to seasonal influenza mortality. However, reported pandemic deaths were laboratory-confirmed – and thus an underestimation – whereas seasonal influenza mortality is often more inclusively estimated. For a valid comparison, our study used the same statistical methodology and data types to estimate pandemic and seasonal influenza mortality. Methods and FindingsWe used data on all-cause mortality (1999–2010, 100% coverage, 16.5 million Dutch population) and influenza-like-illness (ILI) incidence (0.8% coverage). Data was aggregated by week and age category. Using generalized estimating equation regression models, we attributed mortality to influenza by associating mortality with ILI-incidence, while adjusting for annual shifts in association. We also adjusted for respiratory syncytial virus, hot/cold weather, other seasonal factors and autocorrelation. For the 2009 pandemic season, we estimated 612 (range 266–958) influenza-attributed deaths; for seasonal influenza 1,956 (range 0–3,990). 15,845 years-of-life-lost were estimated for the pandemic; for an average seasonal epidemic 17,908. For 0–4 yrs of age the number of influenza-attributed deaths during the pandemic were higher than in any seasonal epidemic; 77 deaths (range 61–93) compared to 16 deaths (range 0–45). The ≥75 yrs of age showed a far below average number of deaths. Using pneumonia/influenza and respiratory/cardiovascular instead of all-cause deaths consistently resulted in relatively low total pandemic mortality, combined with high impact in the youngest age category. ConclusionThe pandemic had an overall moderate impact on mortality compared to 10 preceding seasonal epidemics, with higher mortality in young children and low mortality in the elderly. This resulted in a total number of pandemic deaths far below the average for seasonal influenza, and a total number of years-of-life-lost somewhat below average. Comparing pandemic and seasonal influenza mortality as in our study will help assessing the worldwide impact of the 2009 pandemic.

WHO: Influenza A (H1N1): Number of Deaths: India data was reported at 0.000 Person in 06 Jul 2009. This stayed constant from the previous number of 0.000 Person for 05 Jul 2009. WHO: Influenza A (H1N1): Number of Deaths: India data is updated daily, averaging 0.000 Person from Apr 2009 (Median) to 06 Jul 2009, with 74 observations. The data reached an all-time high of 0.000 Person in 06 Jul 2009 and a record low of 0.000 Person in 06 Jul 2009. WHO: Influenza A (H1N1): Number of Deaths: India data remains active status in CEIC and is reported by World Health Organization. The data is categorized under High Frequency Database’s Disease Outbreaks – Table WHO.D002: World Heath Organization: Influenza A (H1N1): By Countries.

https://fluprint.com/about/section_1.png" alt="Influenza vaccination responders">

The problem

Influenza virus has a devastating societal impact, causing up to 650,000 deaths every year worldwide. Specifically, vulnerable are children and elderly. It is estimated that 1 in 1000 children and elderly every year are hospitalized due to influenza infection. Vaccination can prevent influenza-like illnesses, and thus lower the risk of the virus outbreak. However, currently available vaccines do not always provide protection, even among otherwise-healthy people, leading to serious pandemics. Development of better vaccines depends on our understanding why current vaccines work in some individuals, while fail in others.

About dataset

The FluPRINT is the name of a unified database for a large-scale study exploring novel cellular and molecular underpinnings of successful immunity to influenza vaccines. It contains information on more than 3,000 parameters measured using mass cytometry, flow cytometry, phosphorylation-specific cytometry (phospho-flow), multiplex ELISA, clinical lab tests (hormones and complete blood count), serological profiling with hemagglutination inhibition assay, and virological tests. The dataset represents fully integrated and normalized immunology measurements from 747 individuals from eight clinical studies conducted between 2007 to 2015 at the Human Immune Monitoring Center of Stanford University. The dataset represents a unique source in terms of value and scale, which will broaden our understanding of influenza immunity.

Additional info: https://zenodo.org/record/3222451#.XOb7MaR7lPY

Citation

Tomic A, Tomic I, Dekker CL, Maecker HT and Davis MM. The FluPRINT dataset, a multidimensional analysis of the influenza vaccine imprint on the immune system. Sci Data, doi: 10.1038/s41597-019-0213-4, 2019. 

BackgroundAssessing the mortality impact of the 2009 influenza A H1N1 virus (H1N1pdm09) is essential for optimizing public health responses to future pandemics. The World Health Organization reported 18,631 laboratory-confirmed pandemic deaths, but the total pandemic mortality burden was substantially higher. We estimated the 2009 pandemic mortality burden through statistical modeling of mortality data from multiple countries.Methods and FindingsWe obtained weekly virology and underlying cause-of-death mortality time series for 2005–2009 for 20 countries covering ∼35% of the world population. We applied a multivariate linear regression model to estimate pandemic respiratory mortality in each collaborating country. We then used these results plus ten country indicators in a multiple imputation model to project the mortality burden in all world countries. Between 123,000 and 203,000 pandemic respiratory deaths were estimated globally for the last 9 mo of 2009. The majority (62%–85%) were attributed to persons under 65 y of age. We observed a striking regional heterogeneity, with almost 20-fold higher mortality in some countries in the Americas than in Europe. The model attributed 148,000–249,000 respiratory deaths to influenza in an average pre-pandemic season, with only 19% in persons <65 y. Limitations include lack of representation of low-income countries among single-country estimates and an inability to study subsequent pandemic waves (2010–2012).ConclusionsWe estimate that 2009 global pandemic respiratory mortality was ∼10-fold higher than the World Health Organization's laboratory-confirmed mortality count. Although the pandemic mortality estimate was similar in magnitude to that of seasonal influenza, a marked shift toward mortality among persons <65 y of age occurred, so that many more life-years were lost. The burden varied greatly among countries, corroborating early reports of far greater pandemic severity in the Americas than in Australia, New Zealand, and Europe. A collaborative network to collect and analyze mortality and hospitalization surveillance data is needed to rapidly establish the severity of future pandemics.Please see later in the article for the Editors' Summary

Influenza Vaccine Market Outlook

In 2023, the global influenza vaccine market size was valued at approximately USD 5.3 billion and is expected to reach USD 8.2 billion by 2032, growing at a compound annual growth rate (CAGR) of 4.9% during the forecast period. This growth can be attributed to increasing awareness about the importance of vaccination among the global population, advancements in vaccine technology, and the continuous efforts by governments and healthcare organizations to reduce the burden of influenza-related illnesses and deaths.

The growing awareness and educational campaigns about the importance of influenza vaccination are significant growth factors for the market. Health organizations like the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) have been proactive in promoting yearly flu vaccinations, especially for vulnerable populations such as the elderly, young children, and individuals with compromised immune systems. These efforts are amplified through various media channels, community outreach programs, and collaborations with healthcare providers, resulting in increased vaccination rates.

Technological advancements in vaccine production are another critical driver of market growth. Innovations such as cell-based and recombinant vaccine production methods have improved the efficiency and speed of vaccine development. These technologies not only enhance the scalability of vaccine production but also contribute to the development of more effective and safer vaccines. For instance, the transition from traditional egg-based methods to cell-based production reduces the dependence on egg supplies and enhances the responsiveness to influenza virus mutations, ensuring a more tailored vaccine formulation each flu season.

Government initiatives and funding play a pivotal role in driving the influenza vaccine market. Numerous governments globally recognize the public health implications of influenza outbreaks and are investing significantly in vaccination programs. Subsidies, grants, and public-private partnerships are common strategies employed to ensure widespread vaccine availability and affordability. Additionally, policies mandating vaccinations for certain groups, such as healthcare workers and school children, further bolster market demand. These governmental measures not only increase vaccine uptake but also drive continuous research and development in the field.

The role of the Flu Vaccine in public health cannot be overstated. Each year, the flu vaccine is reformulated to combat the most prevalent strains of the influenza virus, providing a crucial line of defense against potential outbreaks. This annual update is vital as it helps to reduce the incidence of flu-related complications, hospitalizations, and deaths. The flu vaccine is especially important for high-risk groups, including the elderly, young children, and those with chronic health conditions. By receiving the flu vaccine, individuals not only protect themselves but also contribute to the broader community immunity, reducing the spread of the virus and protecting those who are unable to be vaccinated. The continuous development and distribution of the flu vaccine are essential components of global health strategies aimed at minimizing the impact of seasonal influenza.

Regionally, North America and Europe have historically dominated the influenza vaccine market due to well-established healthcare systems, high awareness, and robust government support. However, Asia Pacific is expected to witness the fastest growth during the forecast period. Factors such as increasing population, rising healthcare expenditure, and improving healthcare infrastructure contribute to this regional surge. Moreover, emerging economies in the region are increasingly investing in healthcare, including vaccination programs, to combat infectious diseases, thereby driving market growth.

Vaccine Type Analysis

The influenza vaccine market is segmented by vaccine type into trivalent and quadrivalent vaccines. Trivalent vaccines, which contain three strains of the influenza virus (two A strains and one B strain), have been the standard for many years. However, quadrivalent vaccines, which include an additional B strain, have gained prominence due to their broader protection. The shift towards quadrivalent vaccines is driven by the need for enhanced efficacy, especially given the unpredictable nature of influenza virus mutations. As a result, manufacturers are

For centuries influenza epidemics have plagued man; with influenza probably being the disease described by Hippocrates in 412 BC. Today it remains a major cause of morbidity and mortality worldwide with large segments of the human population affected every year. Many animal species can be infected by influenza viruses, often with catastrophic consequences. An influenza pandemic is a continuing global level threat. The 1918 influenza pandemic is a modern example of how devastating such an event could be with an estimated 50 million deaths worldwide.

Influenza viruses belong to the family of Orthomyxoviridae; viruses with segmented RNA genomes that are negative sense and single-stranded (Baltimore 1971). Influenza virus strains are named according to their type (A, B, or C), the species from which the virus was isolated (omitted if human), location of isolate, the number of the isolate, the year of isolation, and in the case of influenza A viruses, the hemagglutinin (H) and neuraminidase (N) subtype. For example, the virus of H5N1 subtype isolated from chickens in Hong Kong in 1997 is: influenza A/chicken/Hong Kong/220/97(H5N1) virus. Currently 16 different hemagglutinin (H1 to H16) subtypes and 9 different neuraminidase (N1 to N9) subtypes are known for influenza A viruses. Most human disease is due to influenza viruses of the A type. The events of influenza infection have been annotated in Reactome primarily use protein and genome references to the Influenza A virus A/Puerto Rico/8/1934 H1N1 strain.

The influenza virus particle initially associates with a human host cell by binding to sialic acid receptors on the host cell surface. Sialic acids are found on many vertebrate cells and numerous viruses make use of this ubiquitous receptor. The bound virus is endocytosed by one of four distinct mechanisms. Once endocytosed the low endosomal pH sets in motion a number of steps that lead to viral membrane fusion mediated by the viral hemagglutinin (HA) protein, and the eventual release of the uncoated viral ribonucleoprotein complex into the cytosol of the host cell. The ribonucleoprotein complex is transported through the nuclear pore into the nucleus. Once in the nucleus, the incoming negative-sense viral RNA (vRNA) is transcribed into messenger RNA (mRNA) by a primer-dependent mechanism. Replication occurs via a two step process. A full-length complementary RNA (cRNA), a positive-sense copy of the vRNA, is first made and this in turn is used as a template to produce more vRNA. The viral proteins are expressed and processed and eventually assemble with vRNAs at what will become the budding sites on the host cell membrane. The viral protein and ribonucleoprotein complexes are assembled into complete viral particles and bud from the host cell, enveloped in the host cell's membrane.

Infection of a human host cell with influenza virus triggers an array of defensive host processes. This coevolution has driven the development of host processes that interfere with viral replication, notably the production of type I interferon. At the some time the virus counters these responses with the viral NS1 protein playing a central role in the viral response to the host cells defense.