Updated September 10, 2012
What is the incubation period for the influenza virus?
The “incubation period” for an illness refers to the period between the time an individual becomes infected with the illness and the time they begin showing symptoms. The Centers for Disease Control and Prevention (CDC) estimates that it’s between one and four days. The CDC considers people infected with influenza to be infectious—able to transmit the infection to other people—one day before they begin showing symptoms.
How should we clean work spaces if someone in our area becomes sick with flu-like symptoms?
You should follow the same infection-control practices you would use during the normal cold and flu season. To prevent the spread of illness, disinfect commonly touched hard surfaces in the workplace, including counter tops, door knobs, telephones, copy machines, work stations, and bathroom surfaces by wiping them down with a household disinfectant according to directions on the product label. Studies have shown that flu viruses do not remain infectious on environmental surfaces for more than eight hours. Frequent hand washing is the best way to avoid infection from contaminated surfaces.
What are the symptoms of influenza and how serious is it?
Symptoms of influenza include fever, cough, sore throat, body aches, headache, chills, and fatigue. Some people have also reported diarrhea, nausea, and vomiting.
What should I do if I have flu symptoms?
If you have flu-like symptoms, stay home and rest. If you are an MIT student, call MIT Medical to notify them of your illness and to get advice on treatment. If you do become ill, you should avoid contact with other people except to get medical care and stay home until your temperature has remained normal for 24 hours without the use of fever-reducing drugs such as acetaminophen and ibuprofen.
Most patients experience a moderate respiratory illness and recover completely without medical intervention. Antiviral drugs including Tamiflu and Relenza are recommended only in severe cases or in patients with medical conditions that put them at risk for serious complications from the flu.
To avoid spreading the illness to others, the Massachusetts Department of Public Health recommends that individuals who become sick with the flu should avoid close contact with other people until 24 hours after a fever has resolved and body temperature has remained normal without the use of fever-reducing drugs such as acetaminophen and ibuprofen. Human Resources at MIT has additional information on Institute current leave and payment policies, and the policies that will be in effect in the case of more widespread illness or another emergency.
When should I see a medical provider?
Generally, you do not need to be seen for flu-like symptoms unless you are pregnant or have an underlying medical condition that puts you at higher risk for developing serious complications from the flu (see "Who is at higher risk for developing serious complications from influenza?"), or unless your symptoms are serious. In adults, this means:
In children, serious symptoms include:
Who is at higher risk for developing serious complications from flu?
The people who are at higher risk of serious complications from influenza are the same individuals who are at higher risk for developing serious complications from seasonal influenza. These include:
If a member of my family is sick with the flu, do I need to stay home from work?
No. You should stay home only if you get sick with flu-like symptoms (see "What should I do if I have flu symptoms?"). Human Resources at MIT can provide additional information on the Institute's policies regarding time off to care for a sick family member.
How many flu vaccinations will I need for the 2012-13 flu season?
Adults will need just one vaccination. Children between 6 months and 9 years old will need two doses, spaced at least a month apart, if this is the first time they’re receiving a flu vaccination.
How do I get vaccinated against flu?
See our vaccination page to learn how to obtain a flu vaccination.
Is the flu vaccine safe?
Every year, the seasonal flu vaccine produces mild side effects in approximately 5 to 10 percent of people (most commonly, soreness at the site of the vaccination). An extremely small number of people experience a more serious allergic reaction. In general, however, most experts believe that the risk from flu itself is greater than any potential risks from a vaccine, particularly for the most vulnerable groups. The CDC estimates that during a 30-year span (the period from 1976-1977 flu season to the 2006-2007 season), the number of flu-associated deaths in the U.S. ranged from about 3,000 to 49,000 people per season.
There are some people who should not get a flu vaccine without first consulting a physician. These include:
Should I get a vaccination to prevent pneumonia?
Since one of the most severe complications of influenza is the increased risk of developing bacterial pneumonia—especially with the pneumococcus bacteria—pneumococcal vaccine (Pneumovax) is recommended for some people, including:
For more information, see Pneumococcal Polysaccharide Vaccine: What You Need to Know (PDF).