Overview
Influenza or flu common viral infection that can be deadly, especially in high-risk groups. flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs. Some people, such as older people, young children, and people with certain health conditions, are at higher risk of serious flu complications. There are two main types of influenza (flu) viruses: Types A and B. The influenza A and B viruses that routinely spread in people (human influenza viruses) are responsible for seasonal flu epidemics each year
Causes
Influenza viruses travel through the air in droplets when someone with the infection coughs, sneezes or talks. You can inhale the droplets directly, or you can pick up the germs from an object — such as a telephone or computer keyboard — and then transfer them to your eyes, nose or mouth. People with the virus are likely contagious from about a day before symptoms appear until about five days after they start. Children and people with weakened immune systems may be contagious for a slightly longer time.
Influenza viruses are constantly changing, with new strains appearing regularly. If you’ve had influenza in the past, your body has already made antibodies to fight that specific strain of the virus. If future influenza viruses are similar to those you’ve encountered before, either by having the disease or by getting vaccinated, those antibodies may prevent infection or lessen its severity. But antibody levels may decline over time. Also, antibodies against influenza viruses you’ve encountered in the past may not protect you from new influenza strains that can be very different viruses from what you had before.
Symptoms
The flu may seem like a common cold with a runny nose, sneezing and sore throat. But colds usually develop slowly, whereas the flu tends to come on suddenly. And although a cold can be a bother, you usually feel much worse with the flu. Listed below some of the symptoms for both adult and children.
For Children
Children often have similar symptoms to adults but can also have gastrointestinal symptoms, such as nausea, vomiting, and diarrhea.
- breathing difficulties
- rapid breathing
- bluish face or lips
- chest pain or ribs pulling inward as they breathe
- severe aches
- dehydration, for example, not urinating for 8 hours and crying dry tears
- lack of alertness or interaction with others
- a fever above 104°F or any fever in a child under 12 weeks of age
- a fever or cough that goes away but then comes back
- a worsening of any other medical conditions
For Adult
- breathing difficulties
- pain or pressure in the chest or abdomen
- dizziness, confusion, or loss of alertness
- seizures
- not urinating, which may indicate dehydration
- severe pain, weakness, and unsteadiness
- a fever or cough that goes away and then comes back
- a worsening of other existing health conditions.
When to see a Doctor
Most people who get the flu can treat themselves at home and often don’t need to see a doctor. If you have flu symptoms and are at risk of complications, see your doctor right away. Taking antiviral drugs may reduce the length of your illness and help prevent more-serious problems.
If you have emergency signs and symptoms of the flu, get medical care right away. For adults, emergency signs and symptoms can include:
- Difficulty breathing or shortness of breath
- Chest pain
- Ongoing dizziness
- Seizures
- Worsening of existing medical conditions
- Severe weakness or muscle pain
Prevention
- practicing good hygiene, including frequent hand washing
- keeping the immune system strong by following a healthful diet
- quitting or avoiding smoking, as smokers are more likely to develop complications
- staying away from people who have the flu
- People should also stay away from others when they have the flu to avoid spreading it themselves.
