GITNUXREPORT 2026

Influenza Statistics

The flu causes millions of illnesses and tens of thousands of deaths every single year.

Jannik Lindner

Co-Founder of Gitnux, specialized in content and tech since 2016.

First published: Feb 13, 2026

Our Commitment to Accuracy

Rigorous fact-checking · Reputable sources · Regular updatesLearn more

Statistic 1

Influenza causes fever in 80-90% of symptomatic cases.

Statistic 2

Cough is present in 90-98% of influenza patients.

Statistic 3

Myalgias occur in 60-80% of adults with influenza.

Statistic 4

Headache reported in 70-90% of influenza cases.

Statistic 5

Sore throat in 50-80% of patients.

Statistic 6

Fatigue lasts 2-3 weeks in 30% of cases post-influenza.

Statistic 7

Rhinorrhea more common in children (60%) than adults (30%).

Statistic 8

Incubation period averages 2 days (range 1-4 days).

Statistic 9

Viral shedding peaks day 1, lasts 5-7 days in adults.

Statistic 10

Children shed virus 7-10 days, longer if immunocompromised.

Statistic 11

Pneumonia complicates 2-5% of hospitalized adults.

Statistic 12

Myocarditis in 0.4-4% of fatal influenza cases.

Statistic 13

Encephalitis rare, 0.2-2 per million influenza cases.

Statistic 14

Acute respiratory distress syndrome (ARDS) in 10-20% severe cases.

Statistic 15

Otitis media in 30-50% of children with influenza.

Statistic 16

Febrile seizures in 20-30% of influenza A cases in young children.

Statistic 17

Reye syndrome associated with aspirin use, now <1 case/year.

Statistic 18

Lymphopenia (<1000/mm3) in 30-50% hospitalized patients.

Statistic 19

Elevated CRP (>50 mg/L) in 80% of confirmed cases.

Statistic 20

Procalcitonin >0.25 mcg/L suggests bacterial co-infection in 20%.

Statistic 21

Thrombocytopenia (<150,000) in 10-20% severe cases.

Statistic 22

Dyspnea in 40% of adults seeking care.

Statistic 23

Anosmia/hyposmia in 15-30% of influenza cases.

Statistic 24

Conjunctivitis in 10-20% of cases.

Statistic 25

Hoarseness in 30% of patients.

Statistic 26

Chest pain in 10-15% hospitalized adults.

Statistic 27

Diarrhea in 10-20% of children, 5% adults.

Statistic 28

During the 2022-2023 influenza season in the United States, the CDC estimated 31 million flu illnesses, 360,000 hospitalizations, and 21,000 flu deaths.

Statistic 29

Globally, influenza causes an estimated 1 billion cases annually, including 3-5 million severe cases.

Statistic 30

In the US, influenza results in an average of 34.8 million illnesses, 16 million medical visits, 450,000 hospitalizations, and 41,000 deaths per year from 2010-2023.

Statistic 31

The 2009 H1N1 pandemic caused an estimated 151,700 to 575,400 flu-related respiratory deaths worldwide.

Statistic 32

In Europe, during the 2018-2019 season, WHO reported 72,000 excess deaths attributable to influenza.

Statistic 33

Australia's 2019 flu season saw 313,400 laboratory-confirmed cases, a record high.

Statistic 34

In the UK, influenza and pneumonia accounted for 29,516 deaths in 2022.

Statistic 35

India's influenza surveillance from 2016-2021 detected influenza in 12-20% of acute respiratory illness cases.

Statistic 36

Brazil reported 25,692 influenza deaths in 2020, mostly due to A(H1N1)pdm09.

Statistic 37

In Japan, the 2018-2019 season had 14.5 million influenza cases.

Statistic 38

China's national influenza surveillance (2017-2022) showed A(H3N2) dominating 45% of cases.

Statistic 39

South Africa's 2019 sentinel surveillance detected influenza positivity in 8.5% of patients.

Statistic 40

Canada estimated 12,200 flu hospitalizations in 2022-2023.

Statistic 41

In the EU/EEA, 2016-2017 season had up to 170,000 influenza-associated excess deaths.

Statistic 42

Mexico's 2022-2023 season reported 1,200 influenza deaths.

Statistic 43

Influenza accounts for 5-10% of all pneumonia cases globally.

Statistic 44

In the US, children under 5 experience 20% of flu hospitalizations.

Statistic 45

Elderly over 65 represent 70-85% of flu deaths in the US annually.

Statistic 46

Pregnant women have 4-8 times higher hospitalization risk from flu.

Statistic 47

Indigenous populations in Australia have 5 times higher flu hospitalization rates.

Statistic 48

In the US, 2009 H1N1 caused 43-89 thousand deaths.

Statistic 49

Global influenza surveillance detects 100,000+ samples yearly via GISRS.

Statistic 50

Influenza A(H1N1)pdm09 circulates at 20-30% positivity in recent seasons.

Statistic 51

H3N2 causes longer illness duration and higher hospitalization in elderly.

Statistic 52

B/Victoria lineage dominated 40% of cases in 2023 Northern Hemisphere.

Statistic 53

In Africa, influenza positivity rates average 10-15% in SARI cases.

Statistic 54

Russia's 2022-2023 season had 25 million cases reported.

Statistic 55

In the US, flu peaks between December and February in 90% of seasons.

Statistic 56

Southeast Asia sees year-round influenza with two peaks.

Statistic 57

In 1918 pandemic, global deaths estimated at 50 million.

Statistic 58

Global flu deaths 290,000–650,000 annually respiratory.

Statistic 59

US average 34,000 flu deaths per year (2010-2020).

Statistic 60

2017-2018 US season: 61,000 deaths.

Statistic 61

Children <5: 100-200 US flu deaths yearly.

Statistic 62

>65yo: 70-90% of US flu deaths.

Statistic 63

Cardiovascular deaths from flu: 2x pneumonia deaths.

Statistic 64

Pregnant women mortality risk 7x higher.

Statistic 65

Obesity BMI>40: 2-3x mortality risk.

Statistic 66

1918 pandemic: 675,000 US deaths.

Statistic 67

1957 Asian flu: 1.1 million global deaths.

Statistic 68

1968 Hong Kong flu: 1 million global deaths.

Statistic 69

2009 H1N1: 12,469 lab-confirmed US deaths.

Statistic 70

H5N1 avian: 455 human cases, 52% CFR (1997-2023).

Statistic 71

Economic cost US: $11 billion/year healthcare.

Statistic 72

Lost productivity: $60-100 billion/year US.

Statistic 73

Global DALYs from flu: 16.3 million yearly.

Statistic 74

ICU admission mortality 17% adults.

Statistic 75

Bacterial pneumonia causes 20-40% excess flu deaths.

Statistic 76

Underreporting: flu deaths 10-52x pneumonia-coded.

Statistic 77

Annual flu vaccine 40-60% effective against infection.

Statistic 78

High-dose vaccine in >65yo: 24% efficacy vs hospitalization.

Statistic 79

Vaccination prevents 11,000 US deaths yearly.

Statistic 80

Coverage in US children: 60% by season end.

Statistic 81

Elderly coverage: 70% in recent years.

Statistic 82

Vaccine reduces GP visits by 50-60%.

Statistic 83

Live attenuated vaccine 80% effective in children 2-17yo.

Statistic 84

Adjuvanted vaccine 50% better in frail elderly.

Statistic 85

Universal vaccine trials show 20-40% heterologous protection.

Statistic 86

Antiviral prophylaxis 70-90% effective post-exposure.

Statistic 87

School closures reduce spread by 20-30%.

Statistic 88

Handwashing + sanitizer: 20% reduction transmission.

Statistic 89

Face masks in community: 10-20% risk reduction.

Statistic 90

Travel restrictions delay outbreaks by 1-2 weeks.

Statistic 91

Neuraminidase inhibitors prophylaxis 79% effective.

Statistic 92

Herd immunity threshold ~60-70% for seasonal flu.

Statistic 93

Egg-based vaccines mismatch 10-20% due to adaptation.

Statistic 94

mRNA flu vaccines phase 3 trials show 75% efficacy.

Statistic 95

Nasal spray vaccine safe in egg-allergic children.

Statistic 96

Annual revaccination needed due to drift.

Statistic 97

Oseltamivir prophylaxis 89% in households.

Statistic 98

Zanamivir 96% prophylaxis efficacy.

Statistic 99

Baloxavir single dose 90% prophylaxis.

Statistic 100

Influenza virus spreads via droplets within 1-2 meters.

Statistic 101

Aerosol transmission possible in poorly ventilated spaces.

Statistic 102

Infectious period 1 day before to 5-7 days after symptom onset.

Statistic 103

Children shed higher viral loads, longer periods.

Statistic 104

Surface fomites viable up to 48 hours on hard surfaces.

Statistic 105

Virus survives 24 hours on porous surfaces.

Statistic 106

R0 for seasonal flu 1.3 (range 1.2-1.4).

Statistic 107

H1N1pdm09 R0 estimated at 1.5.

Statistic 108

Household secondary attack rate 10-38%.

Statistic 109

School settings have 14-40% attack rates.

Statistic 110

Nosocomial transmission in 1-5% of hospitalized patients.

Statistic 111

Hand hygiene reduces transmission by 16-21%.

Statistic 112

Masks reduce risk by 70-80% in household contacts.

Statistic 113

Social distancing >1m lowers risk by 82%.

Statistic 114

Ventilation reduces airborne transmission by 30-70%.

Statistic 115

Animal reservoirs include pigs (triple reassortant), birds (H5N1).

Statistic 116

Human-to-human sustained for novel strains rare without adaptation.

Statistic 117

Superspreading events contribute 10-20% transmissions.

Statistic 118

Asymptomatic shed virus in 30-50% cases.

Statistic 119

Pre-symptomatic transmission 40-60% of cases.

Statistic 120

Contact tracing identifies 20-30% secondary cases.

Statistic 121

Public transport high risk, attack rate 5-10%.

Statistic 122

Cold weather increases survival, transmission peaks winter.

Statistic 123

Humidity <20% optimal for aerosol stability.

Statistic 124

UV light inactivates virus in minutes.

Statistic 125

Oseltamivir shortens illness by 0.5-1 day.

Statistic 126

Within 48 hours, antivirals reduce complications by 50%.

Statistic 127

Hospitalized patients: oseltamivir reduces mortality 25%.

Statistic 128

Baloxavir faster viral clearance than oseltamivir.

Statistic 129

Zanamivir safe alternative for oseltamivir-resistant cases.

Statistic 130

Peramivir IV for critically ill, reduces ICU stay.

Statistic 131

Supportive care: hydration, antipyretics standard.

Statistic 132

Avoid salicylates in children to prevent Reye.

Statistic 133

Antibiotics only for bacterial superinfection (10-20% cases).

Statistic 134

ECMO survival 60% in severe pediatric H1N1.

Statistic 135

Steroids not recommended routinely, increase mortality.

Statistic 136

Remdesivir in vitro active, limited clinical benefit.

Statistic 137

Favipiravir phase 3 showed no benefit over oseltamivir.

Statistic 138

Recovery median 7 days in uncomplicated cases.

Statistic 139

Resistance to oseltamivir 0.5-2% seasonal H1N1.

Statistic 140

H3N2 resistance low (<1%).

Statistic 141

Post-exposure prophylaxis 75-90% effective.

Statistic 142

Outpatient antivirals reduce hospitalization 40% high-risk.

Statistic 143

ICU mortality 20-30% in severe influenza.

1/143

Sources

Trusted by 500+ publications

+497

Even though it feels like a familiar seasonal annoyance, influenza remains a formidable global adversary, claiming tens of thousands of lives in the US alone each year, with worldwide estimates reaching up to a billion cases and hundreds of thousands of severe outcomes annually.

Key Takeaways

During the 2022-2023 influenza season in the United States, the CDC estimated 31 million flu illnesses, 360,000 hospitalizations, and 21,000 flu deaths.
Globally, influenza causes an estimated 1 billion cases annually, including 3-5 million severe cases.
In the US, influenza results in an average of 34.8 million illnesses, 16 million medical visits, 450,000 hospitalizations, and 41,000 deaths per year from 2010-2023.
Influenza causes fever in 80-90% of symptomatic cases.
Cough is present in 90-98% of influenza patients.
Myalgias occur in 60-80% of adults with influenza.
Influenza virus spreads via droplets within 1-2 meters.
Aerosol transmission possible in poorly ventilated spaces.
Infectious period 1 day before to 5-7 days after symptom onset.
Annual flu vaccine 40-60% effective against infection.
High-dose vaccine in >65yo: 24% efficacy vs hospitalization.
Vaccination prevents 11,000 US deaths yearly.
Oseltamivir shortens illness by 0.5-1 day.
Within 48 hours, antivirals reduce complications by 50%.
Hospitalized patients: oseltamivir reduces mortality 25%.

The flu causes millions of illnesses and tens of thousands of deaths every single year.

Clinical Aspects

Influenza causes fever in 80-90% of symptomatic cases.
Cough is present in 90-98% of influenza patients.
Myalgias occur in 60-80% of adults with influenza.
Headache reported in 70-90% of influenza cases.
Sore throat in 50-80% of patients.
Fatigue lasts 2-3 weeks in 30% of cases post-influenza.
Rhinorrhea more common in children (60%) than adults (30%).
Incubation period averages 2 days (range 1-4 days).
Viral shedding peaks day 1, lasts 5-7 days in adults.
Children shed virus 7-10 days, longer if immunocompromised.
Pneumonia complicates 2-5% of hospitalized adults.
Myocarditis in 0.4-4% of fatal influenza cases.
Encephalitis rare, 0.2-2 per million influenza cases.
Acute respiratory distress syndrome (ARDS) in 10-20% severe cases.
Otitis media in 30-50% of children with influenza.
Febrile seizures in 20-30% of influenza A cases in young children.
Reye syndrome associated with aspirin use, now <1 case/year.
Lymphopenia (<1000/mm3) in 30-50% hospitalized patients.
Elevated CRP (>50 mg/L) in 80% of confirmed cases.
Procalcitonin >0.25 mcg/L suggests bacterial co-infection in 20%.
Thrombocytopenia (<150,000) in 10-20% severe cases.
Dyspnea in 40% of adults seeking care.
Anosmia/hyposmia in 15-30% of influenza cases.
Conjunctivitis in 10-20% of cases.
Hoarseness in 30% of patients.
Chest pain in 10-15% hospitalized adults.
Diarrhea in 10-20% of children, 5% adults.

Clinical Aspects Interpretation

Influenza, far more than "just a bad cold," is a master of misery that reliably brings a choir of coughs and a symphony of aches, but reserves its true virtuosity for severe complications that remind us why this annual virus demands serious respect.

Epidemiology

During the 2022-2023 influenza season in the United States, the CDC estimated 31 million flu illnesses, 360,000 hospitalizations, and 21,000 flu deaths.
Globally, influenza causes an estimated 1 billion cases annually, including 3-5 million severe cases.
In the US, influenza results in an average of 34.8 million illnesses, 16 million medical visits, 450,000 hospitalizations, and 41,000 deaths per year from 2010-2023.
The 2009 H1N1 pandemic caused an estimated 151,700 to 575,400 flu-related respiratory deaths worldwide.
In Europe, during the 2018-2019 season, WHO reported 72,000 excess deaths attributable to influenza.
Australia's 2019 flu season saw 313,400 laboratory-confirmed cases, a record high.
In the UK, influenza and pneumonia accounted for 29,516 deaths in 2022.
India's influenza surveillance from 2016-2021 detected influenza in 12-20% of acute respiratory illness cases.
Brazil reported 25,692 influenza deaths in 2020, mostly due to A(H1N1)pdm09.
In Japan, the 2018-2019 season had 14.5 million influenza cases.
China's national influenza surveillance (2017-2022) showed A(H3N2) dominating 45% of cases.
South Africa's 2019 sentinel surveillance detected influenza positivity in 8.5% of patients.
Canada estimated 12,200 flu hospitalizations in 2022-2023.
In the EU/EEA, 2016-2017 season had up to 170,000 influenza-associated excess deaths.
Mexico's 2022-2023 season reported 1,200 influenza deaths.
Influenza accounts for 5-10% of all pneumonia cases globally.
In the US, children under 5 experience 20% of flu hospitalizations.
Elderly over 65 represent 70-85% of flu deaths in the US annually.
Pregnant women have 4-8 times higher hospitalization risk from flu.
Indigenous populations in Australia have 5 times higher flu hospitalization rates.
In the US, 2009 H1N1 caused 43-89 thousand deaths.
Global influenza surveillance detects 100,000+ samples yearly via GISRS.
Influenza A(H1N1)pdm09 circulates at 20-30% positivity in recent seasons.
H3N2 causes longer illness duration and higher hospitalization in elderly.
B/Victoria lineage dominated 40% of cases in 2023 Northern Hemisphere.
In Africa, influenza positivity rates average 10-15% in SARI cases.
Russia's 2022-2023 season had 25 million cases reported.
In the US, flu peaks between December and February in 90% of seasons.
Southeast Asia sees year-round influenza with two peaks.
In 1918 pandemic, global deaths estimated at 50 million.

Epidemiology Interpretation

These global statistics, ranging from a billion annual cases to tens of thousands of tragic but preventable deaths, collectively paint influenza not as a mere seasonal nuisance but as a persistently formidable and democratic scourge, reminding us that the common flu is anything but common in its consequences.

Mortality

Global flu deaths 290,000–650,000 annually respiratory.
US average 34,000 flu deaths per year (2010-2020).
2017-2018 US season: 61,000 deaths.
Children <5: 100-200 US flu deaths yearly.
>65yo: 70-90% of US flu deaths.
Cardiovascular deaths from flu: 2x pneumonia deaths.
Pregnant women mortality risk 7x higher.
Obesity BMI>40: 2-3x mortality risk.
1918 pandemic: 675,000 US deaths.
1957 Asian flu: 1.1 million global deaths.
1968 Hong Kong flu: 1 million global deaths.
2009 H1N1: 12,469 lab-confirmed US deaths.
H5N1 avian: 455 human cases, 52% CFR (1997-2023).
Economic cost US: $11 billion/year healthcare.
Lost productivity: $60-100 billion/year US.
Global DALYs from flu: 16.3 million yearly.
ICU admission mortality 17% adults.
Bacterial pneumonia causes 20-40% excess flu deaths.
Underreporting: flu deaths 10-52x pneumonia-coded.

Mortality Interpretation

The flu presents itself as an annual nuisance, yet it operates with the grim efficiency of a serial killer, disproportionately targeting the old, the young, the pregnant, and the sick while quietly amassing a staggering body count and economic toll that rivals some wars.

Prevention

Annual flu vaccine 40-60% effective against infection.
High-dose vaccine in >65yo: 24% efficacy vs hospitalization.
Vaccination prevents 11,000 US deaths yearly.
Coverage in US children: 60% by season end.
Elderly coverage: 70% in recent years.
Vaccine reduces GP visits by 50-60%.
Live attenuated vaccine 80% effective in children 2-17yo.
Adjuvanted vaccine 50% better in frail elderly.
Universal vaccine trials show 20-40% heterologous protection.
Antiviral prophylaxis 70-90% effective post-exposure.
School closures reduce spread by 20-30%.
Handwashing + sanitizer: 20% reduction transmission.
Face masks in community: 10-20% risk reduction.
Travel restrictions delay outbreaks by 1-2 weeks.
Neuraminidase inhibitors prophylaxis 79% effective.
Herd immunity threshold ~60-70% for seasonal flu.
Egg-based vaccines mismatch 10-20% due to adaptation.
mRNA flu vaccines phase 3 trials show 75% efficacy.
Nasal spray vaccine safe in egg-allergic children.
Annual revaccination needed due to drift.
Oseltamivir prophylaxis 89% in households.
Zanamivir 96% prophylaxis efficacy.
Baloxavir single dose 90% prophylaxis.

Prevention Interpretation

The flu vaccine is a patchwork shield—sometimes it's a robust fortress for kids and a life-saving barrier preventing thousands of deaths, while for the elderly it's more of a sturdy but leaky umbrella, yet we keep sewing on new layers each year because even imperfect armor is far better than going into battle naked.

Transmission

Influenza virus spreads via droplets within 1-2 meters.
Aerosol transmission possible in poorly ventilated spaces.
Infectious period 1 day before to 5-7 days after symptom onset.
Children shed higher viral loads, longer periods.
Surface fomites viable up to 48 hours on hard surfaces.
Virus survives 24 hours on porous surfaces.
R0 for seasonal flu 1.3 (range 1.2-1.4).
H1N1pdm09 R0 estimated at 1.5.
Household secondary attack rate 10-38%.
School settings have 14-40% attack rates.
Nosocomial transmission in 1-5% of hospitalized patients.
Hand hygiene reduces transmission by 16-21%.
Masks reduce risk by 70-80% in household contacts.
Social distancing >1m lowers risk by 82%.
Ventilation reduces airborne transmission by 30-70%.
Animal reservoirs include pigs (triple reassortant), birds (H5N1).
Human-to-human sustained for novel strains rare without adaptation.
Superspreading events contribute 10-20% transmissions.
Asymptomatic shed virus in 30-50% cases.
Pre-symptomatic transmission 40-60% of cases.
Contact tracing identifies 20-30% secondary cases.
Public transport high risk, attack rate 5-10%.
Cold weather increases survival, transmission peaks winter.
Humidity <20% optimal for aerosol stability.
UV light inactivates virus in minutes.

Transmission Interpretation

The flu is a crafty, airborne menace that thrives in our winter breath, spreads before we even feel sick, and is foiled by the simple, heroic acts of handwashing, masking, and giving each other a little space.

Treatment

Oseltamivir shortens illness by 0.5-1 day.
Within 48 hours, antivirals reduce complications by 50%.
Hospitalized patients: oseltamivir reduces mortality 25%.
Baloxavir faster viral clearance than oseltamivir.
Zanamivir safe alternative for oseltamivir-resistant cases.
Peramivir IV for critically ill, reduces ICU stay.
Supportive care: hydration, antipyretics standard.
Avoid salicylates in children to prevent Reye.
Antibiotics only for bacterial superinfection (10-20% cases).
ECMO survival 60% in severe pediatric H1N1.
Steroids not recommended routinely, increase mortality.
Remdesivir in vitro active, limited clinical benefit.
Favipiravir phase 3 showed no benefit over oseltamivir.
Recovery median 7 days in uncomplicated cases.
Resistance to oseltamivir 0.5-2% seasonal H1N1.
H3N2 resistance low (<1%).
Post-exposure prophylaxis 75-90% effective.
Outpatient antivirals reduce hospitalization 40% high-risk.
ICU mortality 20-30% in severe influenza.

Treatment Interpretation

While antivirals offer a modest head start in the race against the flu clock—shaving off half a day, cutting complications, and saving lives in a pinch—their true power is a conditional shield, best deployed early and strategically within a broader battle plan of supportive care and sober respect for the virus's lethal potential.