- Signs & Symptoms
- Risk Factors
- Treatment Options
Although most people recover from the flu within a few weeks, it can cause serious health problems in some people, particularly those with underlying medical conditions, such as heart or lung diseases, people with weakened immune systems, and the elderly.
What are the common signs and symptoms of flu?
The flu or influenza is a viral infection that affects the respiratory system. The signs and symptoms of influenza (flu) can vary in severity.
Common signs and symptoms of flu
- Fever: A common sign of the flu. The body's temperature rises to help fight off the infection. The fever may be as high as 104°F (40°C) in severe cases.
- Cough: A dry, persistent cough is a common flu symptom. The cough may be severe and last several weeks after the other symptoms have resolved.
- Sore throat: The flu can cause a sore throat, accompanied by difficulty in swallowing.
- Headache: A common flu symptom, especially at the start of the illness. The headache may be severe and accompanied by muscle aches and pains.
- Muscle aches and fatigue: The flu can cause muscle aches and weakness, leading to extreme tiredness or fatigue. This can last several weeks after the other symptoms have resolved.
- Nasal congestion: Nasal congestion or a stuffy nose is a common flu symptom. The congestion may be accompanied by a runny nose and sneezing.
- Body aches: The flu can cause body aches, especially in the muscles and joints. The aches may be severe and may be accompanied by a feeling of weakness or fatigue.
- Chills: The flu can cause chills, which are characterized by a feeling of coldness accompanied by shivering.
- Diarrhea and vomiting: Some people with the flu may experience diarrhea and vomiting although these symptoms are more common in children than adults.
- Loss of appetite: Some people with the flu may lose or have a reduced appetite.
It's important to note that not everyone who has the flu will experience all of these symptoms, and the severity of the symptoms can vary from person to person.
What are the complications of flu?
The flu or influenza is usually a mild illness that goes away on its own. However, the flu can lead to serious complications, especially in certain groups of people.
Complications of the flu
- Otitis media
- An inflammation of the muscles can be caused by the flu. It can lead to muscle weakness, pain, and difficulty moving.
- Cardiac complications
- In rare cases, the flu can lead to sepsis, which is a potentially life-threatening condition that occurs when an infection spreads throughout the body and triggers a severe immune response.
- Symptoms of sepsis include fever, rapid breathing, rapid heart rate, and changes in mental status.
- Reye's syndrome
It's important to see a doctor if you have the flu and are experiencing any of these complications, especially in high-risk individuals such as young children, older adults, and those with underlying health conditions.
Who are at the risk of severe complications of the flu?
Flu (influenza) can cause serious health problems, especially for certain people who are at a higher risk of complications. These include people with certain underlying medical conditions, such as heart or lung disease, weakened immune systems, and older adults. People in these groups need to take extra precautions to prevent the flu.
Certain groups of people are at a higher risk of developing severe complications from the flu, including:
- Old adults: As people age, their immune systems weaken, making them more vulnerable to the flu and its complications.
- Children: Children younger than five years, especially those younger than two years, are at a higher risk of developing severe complications from the flu.
- Pregnant women: Pregnancy can weaken the immune system, making pregnant women more vulnerable to the flu and its complications.
- People with certain underlying health conditions: Certain health conditions, such as asthma, diabetes, and heart disease, can increase the risk of severe complications from the flu.
- People with compromised immune systems: People with compromised immune systems, such as HIV or AIDS, cancer, or organ transplant recipients, are at a higher risk of developing severe complications from the flu.
- Native Americans and Alaskan natives: These populations have a higher risk of complications from the flu, likely due to a combination of genetic, environmental, and cultural factors.
Some other factors that increase the risk of flu complications are as follows:
- Lifestyle factors: People who smoke or have poor hygiene are more likely to get the flu.
- Close contact with others: The flu is highly contagious, so being in close contact with people who have flu, in a crowded place or at a school or work environment, increases the risk of getting the flu.
- Obesity: People who are obese are at a higher risk of complications from the flu.
- Lack of vaccination: Those who are not vaccinated are more at risk of getting the flu.
If you get the flu, it is important to seek medical attention as soon as possible, especially if you are at a higher risk of complications.
What causes the flu?
The most common cause of the flu is the influenza virus, which is a type of RNA virus that belongs to the Orthomyxoviridae family. There are several types of influenza viruses, including types A, B, and C. Influenza A and B viruses are responsible for most outbreaks of the flu, whereas influenza C viruses tend to cause milder respiratory infections.
- Direct spread
- The flu is primarily spread through respiratory droplets that are produced when an infected person talks, coughs or sneezes. These droplets can be inhaled by people who are nearby or they can land on surfaces and be picked up by others, who can then touch their mouths, noses, or eyes and become infected.
- Indirect spread
- The flu can be spread indirectly through contact with contaminated objects or surfaces, such as door handles or shared objects (phones or keyboards).
- Highly contagious
- The flu is highly contagious and can easily spread through a population, especially in crowded places such as schools, offices, and public transportation. The flu is more likely to spread during the winter months when people spend more time indoors and near one another.
- Risk factors
- People with weakened immune systems, such as young children, older adults, and people with certain medical conditions, are at a higher risk of developing severe symptoms and complications from the flu.
Most people recover from the flu within a week or two. Still, it can be serious or even deadly, especially for older adults, young children, and people with underlying health conditions.
What are the treatment options for the flu?
Flu treatment should be started as soon as possible after symptoms begin.
There are several treatment options for flu (influenza), such as:
- Home remedies
- Can be used to relieve the symptoms of the flu and make you feel more comfortable.
- These remedies include getting plenty of rest, drinking fluids, using a humidifier, and taking a warm bath or shower.
- Supportive care
- Over-the-counter medications
- Prescription inhalers
- If you have asthma or any other respiratory condition, your doctor may prescribe an inhaler to help ease your symptoms.
- Antiviral medications
- Flu vaccination
- Getting vaccinated against the flu is the most effective way to prevent getting sick with the flu.
- The flu vaccine is recommended for everyone older than six months and it is especially important for people at a high risk of developing complications from the flu, such as young children, elderly people, and people with certain medical conditions.
Antiviral medications with home remedies are the most effective way to treat severe flu symptoms. Always consult your doctor before starting any medication.
How can you prevent the flu?
You can prevent the flu by combining hygiene, vaccination, and good health habits.
The following are a few ways in which can help you avoid the flu:
- Get vaccinated: The flu vaccine is the most effective way to prevent the flu. It is available in various forms, including as a shot or a nasal spray, and is recommended for everyone aged six months and older.
- Wash your hands frequently: Proper hand hygiene is important in preventing the spread of the flu and other respiratory illnesses. Wash your hands with soap and water for at least 20 seconds or use an alcohol-based hand sanitizer if soap and water are unavailable.
- Avoid close contact with sick people: If you are around people who are sick, try to keep a distance of at least six feet. If you are sick, stay home to avoid spreading the illness to others.
- Stay home when you are sick: If you are sick, it is important to stay home to avoid spreading the flu to others.
- Cover your mouth and nose when you cough or sneeze: Use a tissue to cover your mouth and nose when you cough or sneeze or use the crook of your elbow if a tissue is not available. This helps prevent the spread of respiratory droplets that can contain the flu virus.
- Wear a face mask: Doing this can help reduce the spread of respiratory droplets, especially when it is difficult to maintain physical distance from others.
- Practice good respiratory hygiene: This includes avoiding touching your face, especially your eyes, nose, and mouth, and avoiding close contact with others when you are feeling ill.
- Clean and disinfect frequently touched objects and surfaces: Flu viruses can survive on surfaces for several hours, so it is important to regularly clean and disinfect frequently touched objects and surfaces, such as doorknobs, phones, and keyboards.
- Practice good health habits: Eating a healthy diet, getting enough sleep, and staying physically active can help boost your immune system and reduce your risk of getting the flu.
It's important to note that the best way to prevent the flu is to get a flu vaccine each year. Vaccination is especially important for people at a high risk of complications from the flu, including young children, older adults, and people with certain underlying health conditions. Following these recommendations, you can help protect yourself and others from the flu.
What Are Flu Complications? https://www.webmd.com/cold-and-flu/flu-complications
Flu Symptoms, Causes and Risk Factors https://www.lung.org/lung-health-diseases/lung-disease-lookup/influenza/symptoms-causes-and-risk
Influenza (flu) https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/flu-influenza
Influenza: Questions and Answers information about the disease and vaccines https://www.immunize.org/catg.d/p4208.pdf
Influenza and other respiratory viruses https://www.paho.org/en/topics/influenza-and-other-respiratory-viruses
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