Influenza

Influenza (the flu) is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness, and at times can lead to death. The best way to prevent the flu is by getting a flu vaccination each year. Every year in the United States, on average 5% to 20% of the population gets the flu; more than 200,000 people are hospitalized from flu complications, and; about 36,000 people die from flu-related causes. Some people, such as older people, young children, and people with certain health conditions, are at high risk for serious flu complications.

Types of Influenza

Influenza is caused by three types of RNA viruses called influenza types A, B and C, which all belong to the family Orthomyxoviridae.

Influenza Immunization

Influenza Infection in Animals

Influenza Treatments

Influenza Epidemiology

Influenza Research

Should I get the Flu Shot?

Influenza Prognosis

Influenza Symptoms

Influenza Pandemics

Latest Influenza News and Research

Some acute and chronic viral infections linked to increased risk of cardiovascular disease

In the weeks following a bout of influenza or COVID, the risk of heart attack or stroke may rise dramatically, and chronic infections such as HIV may increase the long-term risk of serious cardiovascular disease events, according to new, independent research published today in the Journal of the American Heart Association, an open access, peer-reviewed journal of the American Heart Association.

29 Oct 2025

Doctors muffled as Florida moves to end decades of childhood vaccination mandates

Florida plans to end nearly a half-century of required childhood immunizations against diseases that have killed and maimed millions of children. Many critics of the decision, including doctors, are afraid to speak up against it.

27 Oct 2025

New epimodulation approach improves outbreak forecasts

During an epidemic, some of the most critical questions for healthcare decision-makers are the hardest ones to answer: When will the epidemic peak, how many people will need treatment at once and how long will that peak level of demand for care last? Timely answers can help hospital administrators, community leaders and clinics decide how to deploy staff and other resources most effectively.

24 Oct 2025

A parent's guide to manage pediatric respiratory illnesses during the virus season

As we head deeper into fall and toward the holiday season, your little one may start to exhibit symptoms like a runny nose, cough, or fever.

24 Oct 2025

How COVID mRNA vaccines may make cancer treatments more effective

Researchers found that COVID-19 mRNA vaccines, when given within 100 days of starting immune checkpoint inhibitors, were linked to significantly longer survival in lung and melanoma cancer patients. The vaccines trigger a powerful type-I interferon response that primes tumors to become more responsive to immunotherapy.

23 Oct 2025

Machine learning model can accurately predict avian influenza outbreak patterns in Europe

Local factors such as seasonal temperature, the year-dependent water and vegetation index, and data on animal density can be used to predict regional outbreaks of avian flu in Europe.

23 Oct 2025

Despite the hoopla, vaccines should be in reach this cough-and-cold season

For people whose autumn agenda includes getting vaccinated against respiratory diseases — covid, flu, and, for some, RSV — this year may be surprisingly routine.

22 Oct 2025

Report maps vaccination's comprehensive benefits for health and economy

A new Gerontological Society of America report, "Concentric Value of Vaccination: Intersecting Health, Economic, and Societal Benefits," provides evidence on the advantages of immunization for individual and population health, economic outcomes, and societal well-being.

22 Oct 2025

CRISPR therapy shows promise against influenza in human lung chips

The Influenza A virus (IAV) has been the cause of six major flu pandemics, responsible for 50 to 100 million deaths globally.

15 Oct 2025

Immune checkpoint inhibitor TIGIT found to promote tissue healing

Immune checkpoint inhibitors are well known as a form of cancer treatment. Researchers at UZH have now identified a new, important function of these inhibitors: promotion of tissue healing.

15 Oct 2025

WHO launches EIOS 2.0 to accelerate detection and response to public health threats

Today, the World Health Organization (WHO), in collaboration with key partners and supporters, launched version 2.0 of the Epidemic Intelligence from Open Sources (EIOS) system, used globally for the early detection of public health threats.

14 Oct 2025

Bird flu virus survives in raw-milk cheese for months

Findings indicate H5N1 virus stability in raw-milk cheese for 120 days, emphasizing the need for revised safety measures in dairy products to protect health.

14 Oct 2025

HEPA purifiers do not fully reduce classroom viral exposure

In a secondary analysis of a study of 200 classrooms, Mass General Brigham researchers found respiratory viral exposures were still high in those with HEPA purifiers, suggesting additional interventions are needed.

10 Oct 2025

Natural nasal microbes offer broad-spectrum antiviral protection

Respiratory viral diseases pose severe threats to animal health and global food security, especially in intensive pig farming systems.

10 Oct 2025

Taste-based flu test that detects infection within minutes

Researchers examine the effectiveness of a novel taste-based sensor for the early detection of influenza infection.

8 Oct 2025

Wary of RFK Jr., Colorado started revamping its vaccine policies in the spring

As Health and Human Services Secretary Robert F. Kennedy Jr.’s dismantling of federal vaccine policy continues to roil the Centers for Disease Control and Prevention, some Democratic-led states have struck out on their own, setting up new systems to help them assess the science and maintain immunization access for their residents.

7 Oct 2025

Breakthrough in RNA-targeted drug discovery offers hope against viral diseases

In a quest to develop new antiviral drugs for COVID-19 and other diseases, a collaboration led by scientists at The Wertheim UF Scripps Institute has identified a potential new drug against the virus that causes COVID-19.

6 Oct 2025

AI combined with the One Health approach can improve pandemic preparedness

Artificial intelligence could be a valuable tool for detecting emerging diseases earlier, researchers from five European universities and research institutes argue in The Lancet Infectious Diseases.

3 Oct 2025

New molecular sensor for taste-based detection of influenza

Flu season is fast approaching in the northern hemisphere. And a taste-based influenza test could someday have you swapping nasal swabs for chewing gum.

2 Oct 2025

Affordable drug found to be effective in treating seriously ill COVID-19 patients

A widely available and affordable drug has been shown to be effective in treating seriously ill COVID-19 patients, according to a new international study led by researchers at the Australian National University (ANU) in collaboration with King's College London.

29 Sep 2025