If there is one thing that we have learned in the last few years, it’s that health is something we should never take for granted. While there are some things we just cannot predict, luckily, there are some things we can and, even better, also prevent!

Introducing What can flu do? A campaign meant to provide information about seasonal flu and the importance of prevention so everyone can live a happy and healthy winter season.

Covid-19 completely turned our lives upside down, especially at the beginning of the pandemic but eventually, we learned that we can do something. By taking preventive measure, we can minimise the risks of seasonal flu infection.

Knowing the risks

So, what can flu do? In some cases, seasonal flu can lead to severe complications. These cases involve people who are more vulnerable, such as children under the age of 5, healthcare workers, pregnant women and women up to 2 weeks postpartum, the elderly, people suffering from obesity as well as people living with chronic, non-transmissible illnesses (also known as Non-Communicable Diseases, NCDs1) such as chronic cardiac disease, asthma, chronic pulmonary and renal diseases, metabolic syndrome and diabetes2

The following disease states are more prevalent in people negatively affected by flu. Click below to learn more.

  • CARDIOVASCULAR DISEASE

    People with heart disease and those who have had a stroke are at higher risk of developing serious flu complications. Among adults hospitalized with flu during recent flu seasons, heart disease was one of the most common chronic (long-term) conditions—about half of adults hospitalized with flu have had heart disease. Studies have shown that flu illness is associated with an increase in heart attacks and stroke.3

  • BLOOD PRESSURE

    Patients with high blood pressure are at raised risk of heart attack and stroke caused by stress that flu infection puts on the body.4

  • DIABETES

    People living with diabetes (type 1, type 2, or gestational) are at higher risk of developing serious complications from seasonal flu. Flu infection can make it harder to manage blood sugar levels, which can lead to complications such as pneumonia5 and a 9-fold increase in the risk of hospitalisation6 and a 2-fold increase in the risk of death.7 Flu can also raise the risk of cardiovascular issues, exacerbating heart failure and acute ischemic heart disease as well as worse diabetes condition, with a poor glycaemic control and acidosis.8,9

  • CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD)

    In patients with lung diseases, the morbidity and mortality caused by respiratory virus infection, such as flu, is considerably greater.10
    People living with chronic obstructive pulmonary disease (COPD) experience 2-fold increase in the risk of hospitalisation after a flu infection.11
    Even if mild, people with asthma can suffer from further inflammation of the airways with flu infection, developing swollen and sensitive airways, which can lead to pneumonia and other acute respiratory diseases. Flu infections can trigger asthma attacks and a worsening of asthma symptoms.12

  • CHRONIC KIDNEY DISEASE

    People with chronic kidney disease at any stage, people who have had a kidney transplant, and people who are undergoing dialysis treatment are at higher risk of developing serious flu complications. Chronic kidney disease weakens immune response, which can make the immune system less able to fight infections, resulting in hospitalisation and even death.13

  • CANCER

    Some cancer treatments can weaken the body’s resistance towards infections, decreasing the ability of the immune system and increasing the risk of catching flu.14 People with low immunity are more likely to develop flu-related complications: 1 in 3 infected patients develop pneumonia.15 After over 10 years of diagnosis the risks of flu hospitalisation and death increases by 9-fold in haematological cancer survivors and 2-fold in non-haematological cancer.16 Moreover, influenza complications could lead to suspension or delay of anticancer therapies.17 Prevention is of paramount importance for people suffering or who have suffered from cancer, since it can lower the risks of complications from flu.18

  • CARDIOVASCULAR DISEASE

  • BLOOD PRESSURE

  • DIABETES

  • CHRONIC OBSTRUCTIVE
    PULMONARY DISEASE (COPD)

  • CHRONIC KIDNEY DISEASE

  • CANCER

People with heart disease and those who have had a stroke are at higher risk of developing serious flu complications. Among adults hospitalized with flu during recent flu seasons, heart disease was one of the most common chronic (long-term) conditions—about half of adults hospitalized with flu have had heart disease. Studies have shown that flu illness is associated with an increase in heart attacks and stroke.3

Patients with high blood pressure are at raised risk of heart attack and stroke caused by stress that flu infection puts on the body.4

People living with diabetes (type 1, type 2, or gestational) are at higher risk of developing serious complications from seasonal flu. Flu infection can make it harder to manage blood sugar levels, which can lead to complications such as pneumonia5 and a 9-fold increase in the risk of hospitalisation6 and a 2-fold increase in the risk of death.7 Flu can also raise the risk of cardiovascular issues, exacerbating heart failure and acute ischemic heart disease as well as worse diabetes condition, with a poor glycaemic control and acidosis.8,9

In patients with lung diseases, the morbidity and mortality caused by respiratory virus infection, such as flu, is considerably greater.10
People living with chronic obstructive pulmonary disease (COPD) experience 2-fold increase in the risk of hospitalisation after a flu infection.11
Even if mild, people with asthma can suffer from further inflammation of the airways with flu infection, developing swollen and sensitive airways, which can lead to pneumonia and other acute respiratory diseases. Flu infections can trigger asthma attacks and a worsening of asthma symptoms.12

People with chronic kidney disease at any stage, people who have had a kidney transplant, and people who are undergoing dialysis treatment are at higher risk of developing serious flu complications. Chronic kidney disease weakens immune response, which can make the immune system less able to fight infections, resulting in hospitalisation and even death.13

Some cancer treatments can weaken the body’s resistance towards infections, decreasing the ability of the immune system and increasing the risk of catching flu.14 People with low immunity are more likely to develop flu-related complications: 1 in 3 infected patients develop pneumonia.15 After over 10 years of diagnosis the risks of flu hospitalisation and death increases by 9-fold in haematological cancer survivors and 2-fold in non-haematological cancer.16 Moreover, influenza complications could lead to suspension or delay of anticancer therapies.17 Prevention is of paramount importance for people suffering or who have suffered from cancer, since it can lower the risks of complications from flu.18

Preventive actions

There are some simple actions that we can all take in our daily lives to protect ourselves from getting seasonal flu and reduce the risk of serious flu-related complications so that we can focus on living our lives in the healthiest way possible.

Let's find out what we can do to minimise risks of the flu!

Get your flu shot19

Annual vaccination is the most effective way to protect yourself20 and to prevent serious complications, particularly for vulnerable people.21 Also, vaccines can help to reduce the recovery period and avert the risks of hospitalisation.22

Wash your hands regularly23

Make sure that you wash your hands with soap and running water regularly and dry them thoroughly with a single-use towel. You can also use an alcohol-based hand rub if you can’t get to soap and water. The World Health Organisation (WHO) recommends also singing “happy birthday” twice to make sure you have spent the right amount of time washing your hands.

Avoid touching your eyes, nose, and mouth24

Germs are most likely to enter your body through the eyes, nose, and mouth. If you do have to touch your eyes, nose, or mouth, do it with a clean tissue, or wash your hands first.

Avoid being around sick people25

Flu is contagious, which means that it spreads easily in crowded spaces. When a person who is actively infected with the flu coughs or sneezes, droplets containing the virus can spread as far as one meter, and infect others who breathe them in. Try to keep a safe distance from the people around you.

If you do not feel well, stay home26

If you feel sick, it is better to isolate to reduce the spread of the virus and the possibility of infecting someone that might be more vulnerable than you.

Flu FAQ

We want to provide you with answers to some frequently asked questions about seasonal flu!

  • What are the symptoms associated with flu?

    Typical features of influenza include abrupt onset of fever and respiratory symptoms such as cough, sore throat, and running nose, as well as systemic symptoms such as headache, muscle aches, and fatigue. The severity of infection can range from asymptomatic illness to hospitalisation, viral pneumonia and death.27

  • Is seasonal flu the same every year?

    Flu viruses are constantly changing, and these genetic changes are monitored by competent authorities like European Centre for Disease Prevention and Control (ECDC), Centres for Disease Control and Prevention (CDC) and World Health Organization (WHO). The information collected by these agencies is crucial given it helps determine whether vaccines and antiviral drugs will work against circulating flu viruses as well as the potential for animal flu viruses to infect humans.28

  • What is the difference between seasonal flu and COVID-19?

    Seasonal flu and COVID-19 both result in respiratory illnesses, but they are caused by different viruses. COVID-19, which spreads more easily than flu, is caused by infection such as the coronavirus variant first identified in 2019. Flu is caused by infection from a flu virus (influenza viruses).
    People infected with COVID-19 can also take longer to develop symptoms, and people can remain contagious for longer periods of time. Compared to flu, COVID-19 also seems to cause more serious illnesses in some people.29

  • Can I get flu and COVID-19 at the same time?

    Yes, it is possible to catch both viruses at the same time. The most effective way to prevent hospitalisation and severe complications from COVID-19 and influenza is vaccination and continue to follow prevention measures.30

  • How infectious is influenza and how is it spread?

    Influenza viruses are mainly spread by droplets generated when an infected person coughs or sneezes, but also through touching surfaces where infectious droplets have landed. People with influenza can be infectious from the day before their symptoms start until about five to seven days after onset of illness. The highest infectivity potential is in the first three or four days after their illness begins, however young children, immune-compromised individuals and those who are critically ill with influenza can shed the virus in the respiratory tract for longer periods.31

  • When is the best time to get vaccinated?

    It is best to get vaccinated before or early in the flu season, ideally before the flu begins spreading in your community. In the northern hemisphere, seasonal circulation of flu is observed between November up to May, and, according to the ECDC, October is an optimal time to receive flu vaccination.32 However, if not already vaccinated you can get vaccinated at any time during the season and, as long as the flu virus is spreading, it will help protect you.33 Getting your flu shot is now even more important, particularly for vulnerable populations, considering the potential co-circulation of the COVID and flu viruses.34

  • Is it better to get sick with flu than to get a flu vaccine?

    No. Flu can be a serious disease, particularly among young children, older adults, and people already suffering from chronic, non-transmissible illnesses (as Non-Communicable Diseases, NCD). Any flu infection can carry a risk of serious complications, even among otherwise healthy children and adults. Therefore, getting vaccinated is a safer choice than risking illness to obtain immune protection.35

  • What may be the side effects of the vaccine?

    Like all medicines, vaccines can cause side effects.36

  • How do I get a flu vaccine?

    In Ireland, you can get your flu vaccine from your GP or pharmacist.

Flu Glossary

Click on the words below to know more about seasonal flu!

Influenza or Flu

Influenza or Flu

There is no difference between influenza and flu. Seasonal flu or influenza is a preventable disease that each year infects approximately ten to thirty per cent of Europe’s population and causes hundreds of thousands of hospitalisations across Europe.37

Virus

Virus

Viruses are infectious units whose small size makes them ultra-filterable. Viruses can replicate only in the living cells that they infect. Within the host cell, viruses start the production of the components from which they are made. They can re-route and modify the course of cellular processes for the optimal execution of their own reproduction.38 Seasonal influenza is caused by the influenza virus.39

Bacteria

Bacteria

Bacteria are unicellular living organisms that can reproduce themselves through the process of cell division.40 There are bacteria that are bad, that we call pathogenic, and they will cause diseases, but there are also good bacteria.41

Vaccine

Vaccine

A preparation that is used to stimulate the body’s immune response against diseases. Vaccines are usually administered through needle injections, but some can be administered by mouth or sprayed into the nose.42

Symptom

Symptom

A physical or mental problem experienced by an individual which may indicate a disease or condition.43 Flu symptoms can be fever, chills, cough, sore throat, runny nose, body aches, headaches and fatigue.44

Incubation Period

Incubation Period

The time interval between initial contact with an infectious agent and appearance of the first sign or symptom of disease in question.45 For flu, the incubation period ranges from one to seven days, and in most cases, it lasts two to three days.46

Strain Variation

Strain Variation

A strain is a variant that is built differently, and so behaves differently, to its parent virus.47 Every two or three years, more virulent flu strains circulate, causing seasonal epidemics.48

Antigenic Drift

Antigenic Drift

It is a constant process that can occur after vaccines are manufactured,49 and which is a subtle change in the surface glycoprotein caused by a point mutation or deletion in the viral gene. This results in a new strain that requires yearly reformulation of the seasonal influenza vaccine.50

Immunity

Immunity

Those physiological mechanisms that enable an individual’s body to recognize materials as foreign and to neutralize, eliminate, or metabolize them without injury to its own tissue.51

Comorbidities

Comorbidities

When more than one disease or condition is present in the same person at the same time. Conditions described as comorbidities are often chronic or long-term conditions.52

Chronic Diseases

Chronic Diseases

Chronic diseases are defined broadly as conditions that last 1 year or more and require ongoing medical attention or limit activities of daily living or both.53

Non-Communicable
Diseases (NCDs)

Non-Communicable Diseases
(NCDs)

Chronic, non-transmissible diseases which are often of long duration and are the result of a combination of genetic, physiological, environmental, and behavioural factors. The main types of (Non-Communicable Diseases) NCDs are cardiovascular diseases, cancers, chronic respiratory diseases, and diabetes.54

Chronic Obstructive Pulmonary Disease (COPD)

Chronic Obstructive Pulmonary
Disease (COPD)

A group of lung conditions that cause breathing difficulties. The main symptoms include increasing breathlessness, particularly when you are active, a persistent chesty cough, frequent chest infections, persistent wheezing.55