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 Pandemics

Influenza Symptoms

Influenza Research

Influenza Epidemiology

Influenza Prognosis

Influenza Treatments

Influenza Infection in Animals

Should I get the Flu Shot?

Influenza Immunization

Latest Influenza News and Research

New model measures social drivers behind infectious disease outbreaks

Influenza spreads in a crowded barracks or prison. Ebola proliferates when per-capita hospital beds plummet below the typical levels in developed countries.

19 Aug 2026

Bladder infection amplifies cognitive problems after traumatic brain injury

A urinary tract infection that follows a moderate brain injury can worsen cognitive problems caused by the injury, new research in mice shows.

19 Aug 2026

Why pregnancy vaccination looks very different in Germany than it did 19 years ago

A 19-year German claims analysis of more than 2.8 million pregnancies found that recorded maternal vaccination increased substantially after national recommendations for influenza and pertussis immunization were introduced. Influenza vaccination reached 19.4% and pertussis vaccination about 37% in 2020-2022, while COVID-19 vaccination was not captured in the databas

19 Aug 2026

Novel norovirus vaccine approach may be adaptable for other RNA viruses

Every RNA virus — from stomach bugs and influenza to chickenpox and the common cold — has its own story to tell, with a unique combination of symptoms, rates of transmission, duration, and chemical blueprint.

19 Aug 2026

Study examines how public deliberation can strengthen public health policymaking

Public health policies are commonly evaluated by their financial costs and expected outcomes. However, policy decisions must also be supported by strong evidence, political feasibility, effective implementation, and public trust to achieve lasting public health benefits.

13 Aug 2026

H5N1 infections remain rare among workers exposed to infected birds

A two-year cohort study of 428 people exposed to H5N1-infected birds in England found fewer than 1% met criteria for infection, with no severe disease or secondary human transmission. The findings support continued PPE use, biosecurity, and targeted surveillance while highlighting challenges around occupational exposure, mucosal contamination, and pandemic preparedness.

10 Aug 2026

Antiviral treatment lowers ICU risk for children with influenza

A new nationwide study finds antiviral treatment is linked to fewer intensive care unit (ICU) admissions and shorter hospital stays for children hospitalized with influenza.

10 Aug 2026

Airplane wastewater pilot shows how airports could track pathogens across borders

Researchers showed that airplane wastewater from a shared US-UK transatlantic route could be collected and analyzed to detect respiratory and enteric pathogen genetic material. The pilot also captured SARS-CoV-2 lineage patterns, including earlier detection of XEC on UK-origin flights, while showing the need for harmonized assays and broader sampling.

4 Aug 2026

Children remain more vulnerable to influenza despite protective antibody levels

Researchers analyzing 1,518 South African household participants found that higher pre-season antibody titers were associated with lower infection risk for three of four influenza viruses studied. Children remained more susceptible after accounting for measured exposure and antibody titers, while younger children shed viral RNA longer than older adults.

3 Aug 2026

Arginine boosts immune defenses against cancer and viral infections

The amino acid arginine helps to keep the human body humming, most notably by synthesizing proteins that carry out a range of cellular processes.

31 Jul 2026

Research reveals how a hidden immune cell army defends human lung tissue

New research led by scientists at La Jolla Institute for Immunology (LJI) and University of Liverpool (UOL) provides the first comprehensive look at how a hidden immune cell army defends the vast, vulnerable tissue of the human lungs.

28 Jul 2026

Early vitamin B3 treatment may benefit children with rare genetic condition

Children with a rare and often fatal genetic condition may benefit from early treatment with vitamin B3, halting their significant deterioration, according to a new study.

28 Jul 2026

Wild bird surveillance reveals how H5Nx flu keeps returning to China

Long-term wild bird surveillance across China revealed shifting H5Nx avian influenza patterns, with H5N1, H5N8, and clade 2.3.4.4b viruses changing over time and across migratory flyways. Genomic analyses suggest recent H5Nx detections in China largely reflect repeated reintroductions through migratory birds rather than sustained local circulation.

26 Jul 2026

Survey finds widespread uncertainty over pregnancy vaccine recommendations

Most Americans are unaware or unsure of which vaccines the Centers for Disease Control and Prevention (CDC) recommends during pregnancy, according to a nationally representative survey of U.S. adults by the Annenberg Public Policy Center (APPC) of the University of Pennsylvania.

22 Jul 2026

ddPCR and NGS for viral surveillance in antiviral drug development

hVIVO explains how ddPCR and NGS support viral surveillance in antiviral trials, from detection and quantification to resistance sequencing.

From hVIVO 20 Jul 2026

Mapping how influenza virus rewires human host cells

Researchers at EMBL Hamburg and collaborators at the Leibniz Research Institute for Molecular Pharmacology (FMP) have mapped how the influenza A virus rewires infected human cells in unprecedented detail.

20 Jul 2026

Study identifies immune response causing severe COVID-19 susceptibility

Although the COVID-19 pandemic has largely subsided, scientists continue to investigate why the virus proved so deadly, causing at least three million deaths worldwide, according to the latest estimates by the World Health Organization (WHO).

19 Jul 2026

New viral library helps scientists study thousands of proteins

To prevent viruses from sickening or killing us - whether it's an individual case of hepatitis B or a COVID pandemic - it's crucial to understand how the proteins they make initiate changes in our bodies that allow them to flourish.

11 Jul 2026

Foodborne threats demand stronger pandemic planning, review says

A Perspective review in npj Science of Food argues that pandemics can weaken food safety systems even when the pathogen is not foodborne. The authors call for One Health planning that integrates food safety into pandemic preparedness, surveillance, laboratory capacity, workforce readiness, and regulation.

2 Jul 2026

Review highlights strong safety and effectiveness of mRNA vaccines

A comprehensive new review published in The Lancet affirms that currently approved mRNA vaccines are safe and highly effective at preventing infectious diseases, including COVID-19.

30 Jun 2026