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.

Should I get the Flu Shot?

Influenza Epidemiology

Influenza Symptoms

Influenza Infection in Animals

Influenza Treatments

Influenza Prognosis

Influenza Pandemics

Influenza Immunization

Influenza Research

Latest Influenza News and Research

Influenza D shows strong potential to spill over to humans

The influenza D virus that researchers say has been flying under the radar since its detection in animals in 2011 can vigorously make copies of itself in human cells and lung tissue samples, a new study shows.

24 Apr 2026

Nasal memory cells help slow influenza virus at entry

Memory cells in the nose slow the influenza virus as soon as it enters the body. They reduce viral levels and may help protect against more severe illness.

23 Apr 2026

UPV researchers develop rapid sensor for detecting active tuberculosis

A research team at UPV is leading the development of a sensor that paves the way for the rapid, selective and cost-effective detection of active tuberculosis.

20 Apr 2026

What still drives childhood vaccine gaps in the United States

A nationwide analysis of provider-verified NIS-Child data from 2010 to 2023 found that US childhood vaccination coverage remained generally high but was consistently shaped by social and structural factors such as maternal education, income, insurance, language, and region. The study also showed that coverage of the combined seven-vaccine series rose over time, yet persistent disparities remained, especially for vaccines such as influenza, hepatitis A, and rotavirus.

19 Apr 2026

Childhood flu infection leaves lasting immune imprint

A study reveals how childhood flu infections impact long-term mortality risk, highlighting implications for vaccination and future outbreak management.

17 Apr 2026

Hidden viral reservoirs in tonsils may explain school-year respiratory outbreaks

A study conducted at the University of São Paulo (USP) in Brazil reveals that tissues such as the tonsils and adenoids can serve as hiding places for the rhinovirus, which causes the common cold and is responsible for most respiratory infections worldwide.

17 Apr 2026

Scientists warn of a silent surge in resistant Aspergillus and Candida

An increasing number of fungi are becoming resistant to medication, posing serious risks for patients with weakened immune systems. That is why fifty researchers from around the world, led by Radboudumc, are calling for action against drug‑resistant fungi. Their call has been published in Nature Medicine.

17 Apr 2026

New flu vaccine approach targets multiple virus strains

Doctors recommend getting your flu shot annually, since the specific influenza strain it targets varies from year to year. But what if the shot could be more effective while protecting against more strains?

15 Apr 2026

NTU Singapore and partners develop new inhaled treatment for severe lung infections

Nanyang Technological University, Singapore (NTU Singapore) is working with China's Southern University of Science and Technology (SUSTech) and Swedish biotechnology company Lipigon Pharmaceuticals AB to develop a new inhaled treatment aimed at helping patients recover faster from severe lung infections.

13 Apr 2026

Nanodisc technology improves study of viral proteins for vaccines

Viruses are masters at invading our cells thanks to specialized proteins that coat their surfaces. When scientists design vaccines, they often create versions of these viral surface proteins to study how our immune systems might respond.

11 Apr 2026

Dynamic AI models detect body tipping points to forecast disease before symptoms

The editorial, "Dynamics-driven medical big data mining: dynamic approaches to early disease forecasting and individualized care," published in Intelligent Medicine (February 2026, Volume 6, Issue 1), was written by Lu Wang (Tianjin Medical University), Han Lyu (Beijing Friendship Hospital, Capital Medical University), and Bin Sheng (Shanghai Jiao Tong University).

10 Apr 2026

Flu vaccines protect children well across Europe, but H3N2 remains harder to stop

Influenza vaccination provided strong real-world protection for children in European primary care across two seasons, with overall vaccine effectiveness of 68% in 2022–2023 and 71% in 2023–2024. Protection was highest against influenza B and H1N1, while H3N2 showed lower and more variable effectiveness, supporting the need for higher uptake and continued monitoring.

8 Apr 2026

High-dose flu vaccine reduces Alzheimer’s risk in older adults

A study reveals high-dose influenza vaccines could modestly reduce Alzheimer's risk in older adults, especially women, offering new insights into prevention.

8 Apr 2026

One Health Summit drives a new wave of coordinated action for global health threats

On World Health Day, global leaders gathered in France for a milestone "One Health Summit", where the World Health Organization (WHO) and partners announced a new wave of concrete actions to better protect people, animals and the planet from future health crises.

7 Apr 2026

Waterfowl movement patterns influence spread of avian influenza outbreaks

The movement patterns of waterfowl, including ducks, swans and geese, may affect the spread of highly pathogenic avian influenza in bird populations, according to a new study from the University of Georgia.

7 Apr 2026

Flu vaccination may cut heart attack and stroke risk after infection

In Danish adults aged 40 years or older, laboratory-confirmed influenza was linked to a sharp short-term rise in first-time heart attack and stroke risk, especially in the first 7 days after infection. Prior same-season influenza vaccination was associated with about half the excess cardiovascular risk among infected individuals, suggesting possible protection even in breakthrough cases.

6 Apr 2026

Novel mucosal vaccine offers broad protection against diverse influenza viruses

A novel vaccine platform has been developed to induce broad, protective immunity against numerous influenza virus infections, showing promise as an effective mucosal vaccine strategy, according to a study published by researchers in the Institute for Biomedical Sciences at Georgia State University.

3 Apr 2026

High-dose flu shots inked to lower Alzheimer's dementia risk in older adults

A large US claims-based study found that adults aged 65 and older who received a high-dose flu vaccine had a lower observed risk of Alzheimer dementia than those who received a standard-dose vaccine, with the association lasting up to 25 months in per-protocol analyses and 28 months in intention-to-treat analyses. The signal appeared stronger and more sustained in women, though the authors stress that the findings are observational and need confirmation in longer prospective studies.

2 Apr 2026

Flu vaccine halves heart attack risk after breakthrough infection

Influenza vaccination could significantly reduce the risk of influenza-associated heart attack and stroke even among people who get infected after getting the vaccine, according to research just published in Eurosurveillance.

2 Apr 2026