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 Symptoms

Influenza Treatments

Influenza Immunization

Influenza Epidemiology

Should I get the Flu Shot?

Influenza Research

Influenza Infection in Animals

Influenza Pandemics

Influenza Prognosis

Latest Influenza News and Research

AI model predicts flu vaccine strains more accurately than WHO

AI-based models like VaxSeer outperform traditional methods in flu vaccine strain selection, enhancing effectiveness and addressing global influenza challenges.

2 Sep 2025

Research reveals molecular details of ME/CFS and long COVID

Patients with chronic fatigue syndrome/myalgic encephalomyelitis (ME/CFS) have heightened innate immune responses to bacteria, viruses, and fungi. While these responses are essential to fight infection, they can cause damage when unchecked.

1 Sep 2025

Genetic clustering of swine influenza revealed in Northern Italy

A new scientific article, titled "Swine influenza surveillance in Italy uncovers regional and farm-based genetic clustering", has been published by Istituto Zooprofilattico Sperimentale delle Venezie as part of the Horizon Europe PAIR project.

29 Aug 2025

New guidelines improve care for respiratory infections in leukemia patients

People with leukemia have a weakened immune system due to the disease itself and treatment, which leads to an increased susceptibility to infections.

28 Aug 2025

New guidelines highlight importance of vaccination for heart patients

The American College of Cardiology has issued Concise Clinical Guidance (CCG) recommending vaccines to protect adults with heart disease against respiratory illness, including influenza, COVID-19 and RSV, and other diseases where vaccination is shown to offer cardiovascular protective benefits.

26 Aug 2025

Generative AI model scans emergency notes to identify high-risk avian influenza exposures

Researchers from the University of Maryland School of Medicine developed a new and highly effective application of an artificial intelligence (AI) tool to quickly scan notes in electronic medical records and identify high-risk patients who may have been infected with H5N1 avian influenza or "bird flu", according to new findings published in the journal Clinical Infectious Diseases.

25 Aug 2025

As measles exploded, officials in Texas looked to CDC scientists. Under Trump, no one answered.

As measles surged in Texas early this year, the Trump administration's actions sowed fear and confusion among CDC scientists that kept them from performing the agency's most critical function — emergency response — when it mattered most, an investigation from KFF Health News shows.

25 Aug 2025

COVID-19 vaccine successes boosted hesitancy - can trust and equity restore immunization?

Researchers show that countries with higher initial COVID-19 vaccine acceptance also achieved stronger booster uptake, but trust and access remain decisive. The commentary warns that vaccine successes also fueled hesitancy, demanding structural reforms, clear communication, and proactive strategies to protect immunization.

21 Aug 2025

Early infection traits help predict future disease spread

When a disease-causing virus or other organism is transmitted from one species to another, most of the time the infection sputters and dies out.

21 Aug 2025

How shifting landscapes drive new bird flu threats across Asia

Landscape changes across the East Asian–Australasian Flyway have reshaped waterfowl migration, increasing interactions with poultry. This shift amplified cross-species viral transmission and raised the risk of avian influenza virus reassortment and diversification.

20 Aug 2025

MIT technique reveals how AI models predict protein functions

Within the past few years, models that can predict the structure or function of proteins have been widely used for a variety of biological applications, such as identifying drug targets and designing new therapeutic antibodies.

19 Aug 2025

It’s almost flu season. Should you still get a shot, and will insurance cover it?

For parents of school-aged children, the fall to-do list can seem ever-growing. Buy school supplies. Fill out endless school forms.

18 Aug 2025

Respiratory viruses awaken dormant breast cancer cells and raise relapse risk

Respiratory viruses such as influenza and COVID-19 can reactivate dormant breast cancer cells in the lungs, raising the risk of metastasis. The process is driven by IL-6–induced cell changes and immune suppression, with the highest recurrence risk soon after infection.

14 Aug 2025

Rare immune mutation unlocks universal antiviral protection

For a few dozen people in the world, the downside of living with a rare immune condition comes with a surprising superpower-the ability to fight off all viruses.

14 Aug 2025

‘Alternative facts’ aren’t a reason to skip vaccines

President Donald Trump's administrations have been notorious for an array of "alternative facts" — ranging from the relatively minor (the size of inaugural crowds) to threats to U.S. democracy, such as who really won the 2020 election.

14 Aug 2025

Rising human adaptive potential seen in 2.3.4.4b clade of H5N1

In recent years, there has been growing concern over the H5N1 influenza virus. It was first identified in birds three decades ago and has now gradually found its way to humans.

12 Aug 2025

Global Virus Network committed to the continued development of mRNA vaccines

The Global Virus Network (GVN), a coalition of leading human and animal virologists from 80+ Centers of Excellence and Affiliates in more than 40 countries dedicated to advancing pandemic preparedness, is unequivocally committed to the continued development and deployment of mRNA vaccines and the global scientific collaboration that makes such innovation possible.

12 Aug 2025

Understanding the biomarkers and mechanisms associated with anti-NMDAR encephalitis

Encephalitis is a potentially life-threatening condition that involves inflammation of the brain. While some cases of encephalitis are caused by a bacterial or viral infection, other cases of 'autoimmune' encephalitis result when the body's own immune system attacks the brain.

8 Aug 2025

Expanded vaccine screening in emergency departments could benefit underserved populations

About 49% of people are unaware of one or more vaccines recommended for them. Further, 86% have not received one or more of these vaccines.

7 Aug 2025

Immune surveillance in children sheds light on virus rebound after COVID

The first paper from a multi-year clinical research study has been published in The Lancet Infectious Diseases: Dynamics of Endemic Virus Re-emergence in Children in the USA Following the COVID-19 Pandemic (2022-2023): A Longitudinal Immunoepidemiologic Surveillance Study and demonstrates how the approach can improve modeling to better predict future outbreaks.

7 Aug 2025