The flu is contagious. People who catch the flu can transmit the virus to another person even before symptoms appear.
A person can still be contagious up to
Keep reading to learn more about how the flu spreads and how people can limit its transmission. We also discuss treatment options and when to see a doctor.
The flu is a contagious infection of the respiratory tract.
Respiratory droplets from sneezing, coughing, breathing, or talking are larger than
Droplets can also deposit on surfaces or objects, or transmission can occur through direct person-to-person contact. Although it is
People who catch the flu are most contagious in the
Other people may carry the virus but not present any symptoms. These asymptomatic individuals can still transmit the virus to another person who may become sick.
People who are generally in good health when they get the flu may be able to infect another person up to 1 week after becoming sick. Young children and people with weakened immune systems may be able to infect others with the flu virus for longer than 7 days.
Once a person catches the flu, they may experience the following
- runny nose
- stuffy nose
- muscle or body aches
- high fever
- sore throat
- vomiting and diarrhea (more common in children)
Not everyone who has the flu will develop a fever.
These symptoms may resemble those of the common cold. Flu symptoms will usually
Most people recover from the flu within a
- young children
- immunocompromised individuals
- pregnant women
- older adults
Complications from the flu may develop in as little as
For most people, the flu causes
Doctors can prescribe antiviral medications to treat or prevent the flu during outbreaks in hospitals or long-term care facilities.
Antiviral drugs to treat the flu resulting from the influenza A and B viruses include:
- oseltamivir (Tamiflu)
- zanamivir (Relenza)
- peramivir (Rapivab)
Doctors can prescribe oseltamivir to people aged 1 year and older to prevent the flu in those belonging to high risk groups in outbreak situations.
Amantadine (Symmetrel) and rimantadine (Flumadine) are two antivirals effective against only influenza A. However, in recent years, influenza A has developed a resistance to these two drugs.
The best treatment for the flu is prevention. Flu viruses are
All year round, but particularly during the flu season, people
- stay home if they are ill
- avoid contact with others who are sick
- cover their nose and mouth when sneezing
- wash their hands often
- avoid touching their face, eyes, mouth, and nose
- clean and disinfect surfaces and objects with a cleaner that kills viruses that cause the flu
The best way to prevent the flu is to get the flu vaccine every year. Experts recommend vaccination for everyone aged 6 months and older, with people over 65 years of age receiving high dose vaccination.
The vaccine contains some egg protein, but it is safe for people with an egg allergy who only develop hives.
Healthy people who catch the flu do not usually need
Medical attention is necessary for people in high risk populations, such as young children, adults over 65 years of age, and people with certain chronic health conditions.
Anyone who feels very ill or worried about their flu symptoms should speak with a doctor. The following table lists the
|Rapid breathing or trouble breathing||Shortness of breath or difficulty breathing|
|Blue color to the lips or face||Persistent pain or pressure in the chest or abdomen|
|Chest pain||Dizziness, confusion, inability to stimulate|
|Ribs pulling in with each breath||Seizures|
|Severe muscle pain||Not urinating|
|Not urinating, dry mouth, no tears when crying||Severe weakness or unsteadiness|
|Not alert or interacting with others||Severe muscle pain|
|Seizures||Fever or cough that improves but then returns or worsens|
|Fever above 104°F||Worsening of chronic conditions|
|Any fever in children less than 12 weeks old|
|Fever or cough that improves but then returns or worsens|
|Worsening of chronic conditions|
Some people may not know whether they have the flu or another infection because the symptoms of the flu are
If a doctor needs to know whether a person has the flu, they will order a laboratory test that detects parts of the virus in nasal or throat secretions.
A doctor may not always order a test to detect the flu virus in people with flu symptoms. The results of the test do not necessarily influence how the doctor will treat the person. With mild symptoms, doctors recommend that people stay home to prevent the spread of the flu.
People at risk of complications from the flu should consult with a doctor to monitor the progression of the infection closely. These individuals are more likely to require hospitalization and have a higher risk of complications. In some cases, the flu can even be fatal.
The flu is contagious from the day before symptoms begin, which means that people can transmit the flu virus to another person before they notice that they are unwell.
An otherwise healthy person remains contagious until about a week after the appearance of symptoms. Others may continue to spread the flu after 7 days.
To limit the spread of the flu, doctors recommend annual flu shots, frequent hand washing, and cleaning of frequently touched surfaces at home, school, and work.