01 H1N1 Flu Disease FAQs (General Information)
The H1N1 flu virus is a new strain of the influenza or flu virus that first appeared last April and has spread around the world. This new virus was first detected in people in the United States in April 2009. This virus is spreading from person-to-person worldwide, probably in much the same way that regular seasonal influenza viruses spread.
On June 11, 2009, the World Health Organization (WHO) signaled that a pandemic of 2009 H1N1 flu was underway. World Health Organization (WHO) http://www.who.int/csr/disease/swineflu/en/index.html.
The symptoms of H1N1 flu in people are similar to the symptoms of regular human seasonal flu infection. They include: fever, lethargy (lack of energy), lack of appetite, and coughing. Some people with H1N1 flu have also reported runny nose, sore throat, nausea, vomiting, and diarrhea.
Like seasonal flu, H1N1 flu in humans can vary in severity from mild to severe. Severe disease with pneumonia, respiratory failure, and even death is possible with H1N1 flu infection. Sometimes bacterial infections may occur at the same time as or after infection with flu viruses and lead to pneumonias, ear infections, or sinus infections.
What is the incubation period of the H1N1 (swine) flu? How long will it take to get the flu after being exposed?
The estimated incubation period is unknown and could range from 1 to 7 days, and more likely 1 to 4 days. Persons with novel H1N1 flu virus infection should be considered potentially contagious (able to spread disease) for up to 7 days after illness onset. Persons who continue to be ill longer than 7 days should be considered potentially contagious until symptoms have resolved. Children, especially younger children, might be contagious for longer periods. People with influenza-like illness should stay home for at least 24 hours after their fever is gone (without the use of fever-reducing medicine).
At this time, there is not enough information to predict how severe this H1N1 flu outbreak will be over the course of the flu season, or how it will compare with seasonal influenza.
With seasonal flu, we know that seasons vary in terms of timing, duration and severity. Seasonal influenza can cause mild to severe illness, and at times can lead to death. Each year, in the United States, on average 36,000 people die from flu-related complications and more than 200,000 people are hospitalized from flu-related causes. Of those hospitalized, 20,000 are children younger than 5 years old. Over 90% of deaths and about 60 percent of hospitalization occur in people older than 65.
So far, with H1N1 flu, the largest number of H1N1 flu confirmed and probable cases have occurred in people between the ages of 5 and 24-years-old. Pregnancy, as well as previously recognized high risk medical conditions from seasonal influenza appear to be associated with increased risk of complications from the H1N1 flu.
Certain people are more likely to get complications from H1N1 flu. They are 1) Children younger than 5 years old; 2) Pregnant women; and 3) People of any age with chronic (long-lasting) medical conditions (such as asthma, diabetes, kidney disease, or heart disease). Unlike with seasonal flu, adults older than 64 years do not appear to be at increased risk of H1N1 flu-related complications thus far.
Complications from the flu can include pneumonia, bronchitis, and sinus and ear infections. The flu can also make chronic health problems worse. For example people with asthma may experience asthma attacks while they have the flu and people with chronic congestive heart failure may have worsening of this condition that is triggered by the flu. If you are concerned about your health risks, see your doctor.
The H1N1 flu virus is spread from person to person the same ways that seasonal flu is spread: usually when someone with the flu coughs or sneezes close to another person, or coughs or sneezes into their own hands and touches another person’s hands or face.
Sometimes people may become infected by touching something with flu viruses on it, such as a door knob or handle, and then touching their mouth or nose. Flu virus survives in the environment for a few hours and sometimes longer. The H1N1 virus is new. Research is being conducted to better understand its characteristics. Studies have shown that influenza (flu) viruses in general can survive on environmental surfaces and can infect a person for up to 2 to 8 hours after being deposited (left) on surfaces like cafeteria tables, doorknobs, and desks.
Frequent hand washing by people with and without the flu will help reduce the chance of spreading the virus from person to person and from environmental surfaces. You cannot get the H1N1 swine flu from eating pork or touching a pig.
If you have a flu-like illness, your doctor will consider multiple factors when he or she examines you. Not all patients will be screened for H1N1 virus. Factors that will guide your doctor's decision to test include whether the virus is widespread, exposure to probable or confirmed cases, and severity of illness.
In California, most doctors are no longer testing patients. Instead they are mostly treating flu illness, as needed.
You are unlikely to get infected with the same exact strain of influenza (flu) more than once. Most people with flu-like illness since spring 2009 don't know whether they were infected with H1N1 or another flu virus strain. If you think you had H1N1 infection, ask your doctor if you should be vaccinated.
Even if you had a confirmed case of H1N1 flu, you can still get infected with other flu strains. You should get the seasonal flu vaccine if it is recommended by your health care provider.
No, the current H1N1 flu virus is a new virus, different from the 1918 pandemic flu strain that was so deadly. It's too soon to draw any definitive conclusions about what this variation of the virus will do but it appears to be acting more like a seasonal flu. Persons at high risk of illness and complications, as well as those with cancer, with weakened immune systems, or with HIV infection may be at higher risk for severe illness due to H1N1 flu.
The viruses detected in the U.S. in April 2009 are different from the H1N1 flu virus that caused an outbreak in 1976. Most genetic parts of these viruses are similar to other H1N1 viruses from North America and Europe.
The signs and symptoms of H1N1 flu are the same in pregnant women as in other people: fever, cough, and sore throat. Other symptoms can include body aches, headache, runny nose, fatigue, vomiting and diarrhea.
Because pregnant women can get sicker than other people who get 2009 H1N1 flu, they should call their doctor right away if they have flu symptoms.
Infants who are not breastfeeding are in general at higher risk of infection and hospitalization for severe respiratory illness than infants who are breast fed. Women who are not sick with flu should be encouraged to start breastfeeding early and feed often. Ideally, a baby should get most of its nutrition from breast milk to receive as many antibodies as possible from its mother.
The risk for H1N1 transmission (spread) through breast milk is unknown. However, with seasonal flu, it seems that the virus does not usually get into the blood stream and cross into breast milk. Sick women who are able to express (pump) their milk for bottle feedings by a healthy family member should be encouraged to do so if their doctor or other health care provider agrees. A mother who is taking antiviral medications (drugs that fight viruses) to prevent or treat H1N1 infection can still breastfeed if her health care provider agrees.
Sick women who don't have anyone to help with infant care while they are ill should wash their hands often, and practice good hygiene habits when coughing or sneezing. Women with flu-like illness are advised to use facemasks when feeding and caring for their babies.
During an epidemic, CDC works with state and local public health agencies to reduce transmission (spread) and illness severity and provide information to help healthcare providers, public health officials, and the public. See www.cdc.gov for more information about CDC's activities.
See H1N1 Flu FAQ for Information about the California Department of Public Health (CDPH) and H1N1 Flu activities 03.13 What is being done to protect Californians?
For workplace and occupational health issues associated with H1N1 influenza (flu) virus, visit the H1N1 Flu and the National Institute of Occupational Safety and Health (NIOSH) Web sites for the latest guidance documents. (http://www.cdc.gov/niosh.)
Businesses should prepare for influenza first, by reviewing their current pandemic flu plan or developing a new plan. Involve employees in development and review of the plan. Conduct an exercise, drill, or discussion to test key components of the plan. Share the plan with employees and explain what policies, leave options, pay, and benefits will be available to them. See CDPH H1N1 Flu Information for Businesses and Employers http://www.cdph.ca.gov/HealthInfo/discond/Pages/H1N1Employers.aspx, and CDC H1N1 Resources for Businesses and Employers http://www.cdc.gov/h1n1flu/business/.
Businesses should also prepare for influenza by taking the following actions:
Engage state and local health department to confirm channels of communication and methods for dissemination (sharing) of local outbreak information.
Review sick-leave policies and consider making them flexible and consistent with public health recommendations. Make sure employees are well-aware of these policies.
Try to provide flexible leave policies to allow workers to stay home to care for sick household members or for children, if schools dismiss students or childcare programs close.
Share best practices with other businesses in the community. Work with companies in your supply chain as well as chambers of commerce and local associations to improve response efforts.
Add a "widget" or "button" to the company Web page or employee Web site so employees can access the latest information on the flu.
Purchase supplies such as tissues, soap, and alcohol-based hand cleaners to encourage healthful habits in the workplace.
California Department of Public Health, Office of Public Affairs