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 Pandemics

Influenza Prognosis

Should I get the Flu Shot?

Influenza Epidemiology

Influenza Treatments

Influenza Research

Influenza Immunization

Influenza Infection in Animals

Latest Influenza News and Research

Study reveals how germinal centers consistently produce antibodies

A new study tracking thousands of B cells across more than 100 germinal centers in mice reveals how the system consistently produces highly effective antibodies.

7 Jun 2026

Flu drugs may reduce cognitive decline in people with HIV

A class of flu drugs may reduce cognitive decline and premature aging in people living with chronic viral infection, reports a new study led by Northwestern University that began with blood samples from people with HIV and extended into preclinical drug trials.

5 Jun 2026

Universal Sarbeco coronavirus vaccine proves safe in first human trial

The first human clinical trial of a universal Sarbeco coronavirus vaccine, developed by the University of Cambridge and spin-out DIOSynVax (DVX) Ltd, has shown that the vaccine is safe and has no significant side-effects.

4 Jun 2026

Cross-reactive T cells target measles and dangerous Nipah viruses

T cells are some of the immune system's most important warriors. They can stop tumor growth and even fight off severe infections.

2 Jun 2026

New discovery provides insights into how seasonal influenza viruses infect people

Scientists investigating how influenza viruses replicate within cells "accidentally" discovered that different flu viruses use distinct strategies to infiltrate cells in the first place.

2 Jun 2026

Pediatric influenza vaccination effectively protects young children

Pediatric flu vaccines significantly reduce the number of childhood cases of influenza, new research from Harvard Medical School confirms.

1 Jun 2026

How a tiny H5N1 dose triggers massive virus shedding in cow milk

Experimental infection studies in lactating Holstein cows showed that H5N1 B3.13 can infect the bovine mammary gland at doses as low as 10 TCID50, producing extremely high viral loads in milk. However, the virus did not transmit to sentinel cows through repeated exposure to contaminated milking equipment or through close contact under high-biocontainment conditions, suggesting that real-world dairy-farm spread depends on additional cofactors.

25 May 2026

New computational pipeline improves effectiveness of pan-Ebola neutralizing antibodies

A team led by Professor Wei Yang at the National Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, has developed a computational-experimental pipeline that synergistically optimizes antibody framework regions (FR) and complementarity-determining regions (CDR).

24 May 2026

Boston Children's scientists create new booster-free mRNA vaccine strategy

In a new study published in Nature Immunology, researchers at Boston Children's Hospital demonstrated that pairing the original COVID-19 mRNA vaccine with an immune system enhancer, known as an adjuvant, extended the duration of the vaccine's protection in mice from a few months up to two years.

22 May 2026

Wastewater tracking catches hospital fungus before patients show symptoms

A new UNLV-led wastewater surveillance study brings scientists one step closer in the global race to detect and deter skyrocketing cases of a potentially deadly drug-resistant fungus that puts hospital patients at risk of serious blood, heart, or brain infections.

20 May 2026

Adjuvanted and high-dose flu vaccines protect older adults equally well

In a large study of 429,595 adults aged 65 years or older, adjuvanted and high-dose influenza vaccines showed no significant difference in protection against PCR-confirmed influenza. The findings support current recommendations that both enhanced vaccines are reasonable options for older adults, while second-season results may further refine the evidence.

20 May 2026

New mRNA vaccine strategy dramatically amplifies cancer-fighting T cells

Engineers from the University of Houston, MIT and Harvard have developed a new mRNA-based strategy that dramatically amplifies the T-cell response to vaccines - an advance that could lead to far more powerful cancer vaccines and stronger protection against infectious diseases.

19 May 2026

Health experts outline symptoms and risks of shipboard hantavirus

It's one of the cruisegoer's biggest fears: a contagious disease outbreak at sea.

18 May 2026

Turning the flu virus into a powerful tool to fight cancer

A recent Views & Comments article published in Engineering highlights advances in repurposing influenza viruses as flexible therapeutic platforms for infectious diseases and cancer, driven by progress in reverse genetics and viral vector engineering.

14 May 2026

New mRNA adjuvant dramatically boosts T-cell vaccine responses in mice

MIT engineers have developed a new way to amplify the T-cell response to mRNA vaccines - an advance that could lead to much more powerful cancer vaccines and stronger protection against infectious diseases.

13 May 2026

Wastewater monitoring may predict influenza outbreaks one week earlier

Seasonal influenza can spread rapidly, and timely information on rising cases is essential for public health decisions and healthcare resource planning.

13 May 2026

Study reveals hidden airborne infection pathways in multi-family buildings

Airborne diseases like measles, influenza and COVID-19 can easily spread between units in multi-family buildings via a type of bathroom ventilation system commonly used around the world, new research suggests.

13 May 2026

Cardiometabolic diseases remain leading cause of excess American mortality

Between 1999 and 2022, the US had substantially higher death rates than other wealthy nations, largely due to cardiovascular disease, metabolic diseases (including diabetes), Alzheimer's disease and related dementias, and drug and alcohol complications.

8 May 2026

Infectious H5N1 virus detected in dairy farm air

Findings from California dairy farms show H5N1 in air and wastewater, indicating overlooked transmission routes and implications for outbreak management.

8 May 2026

Study explores nasal spray flu vaccine effects in children

A new study will explore the effects of a nasal spray flu vaccine on children's immune systems, aiming to boost future protection and lower vaccine hesitancy rates.

7 May 2026