H1N1 Swine Flu: Symptoms, Prevention, and Treatment
Author: Disabled World (DW)
Updated/Revised Date: 2 Nov 2026
Table of Contents:
Synopsis - Definition - About This Section - FAQs - Publications - Subtopics
Synopsis
Learn about the H1N1 swine flu virus, including its symptoms, how it spreads, prevention steps, antiviral treatment, and infection control recommendations.
At a Glance
- 1 - You cannot catch swine flu from eating bacon, ham, or other pork products.
- 2 - A close contact is defined as being within six feet of someone with a confirmed case of the virus.
- 3 - Antiviral treatment may use oseltamivir (Tamiflu) or zanamivir (Relenza) and works best when started soon after symptoms begin.
- 4 - A person can be contagious a day before symptoms appear and for up to 7 days after, while children can spread it for as long as 10 days.
Topic Definition
- H1N1 Swine Flu
H1N1 swine flu is a respiratory illness caused by the H1N1 strain of the influenza A virus, which earned its name because earlier cases were linked to direct contact with pigs before the virus began spreading readily from person to person. Its symptoms closely resemble seasonal flu and commonly include cough, fever, sore throat, body aches, fatigue, and chills, though some people also experience nausea, vomiting, or diarrhea, and severe cases can lead to pneumonia and breathing problems. The virus spreads much like seasonal influenza, through droplets released when an infected person coughs or sneezes and by touching contaminated surfaces, and it can worsen existing conditions such as asthma or diabetes. Because it cannot be reliably told apart from other flu without a lab test, prevention through hand washing, respiratory hygiene, and avoiding close contact with sick people, along with prompt antiviral treatment when needed, is central to managing it.
Overview
The Sporadic H1N1 Swine Influenza virus (SIV) infection that people can experience has the potential to produce a number of clinical signs and symptoms. Many of the persons with SIV infection have a history of recent, physical contact with pigs before becoming ill; although proximity without direct contact with pigs has also been reported among persons with SIV. Limited, nonsustained transmission of SIV between people has been documented in published literature. Additionally, there have been confirmed cases of SIV that have not occurred through exposure to pigs.
Symptoms of Swine Flu
Many times, people experience symptoms such as a cough, fever, or sore throat; although symptoms like mild respiratory illness to include nasal congestion without a fever, or occasional severe disease have also been reported. Additional symptoms that have been reported by people with swine flu include diarrhea, vomiting, headache, myalgia, dyspnea, fatigue, and chills. Some people have experienced conjunctivitis, although it is rare. More severe disease to include pneumonia and respiratory failure have also been reported in association with swine flu. A consideration regarding SIV involves the exacerbation of other, underlying and chronic medical conditions that a person may experience, or invasive bacterial infections.
Clinical Care and Collection of Respiratory Specimens
People who either have, or are suspected of having the SIV virus, should be considered potentially contagious for a period of seven days from the date of illness onset. People who continue to exhibit symptoms of illness for a period of time that extends past seven days should be considered contagious until their symptoms have resolved. Children; younger children in particular, have the potential to remain contagious for longer periods of time. During the 2009 H1N1 pandemic, the virus mostly affected children and younger adults rather than older people, and worldwide about 80 percent of the deaths were in people younger than 65. The time a person may remain infectious varies according to the strain of swine flu involved.
Defining Swine Flu Cases
A confirmed case of SIV is defined as a person who is experiencing an acute respiratory illness combined with laboratory confirmation of the SIV virus through one of the following tests:
- Real-time RT-PCR
- Viral culture
- Four-fold rise in swine influenza A virus specific neutralizing antibodies
Suspected cases of SIV are defined as persons who are experiencing respiratory illness who may have had close contact with someone with a confirmed case of SIV while that person was ill or is an acutely ill person, such as someone with an acute respiratory illness, or contact with a person who has a history of recent contact with an animal with either a confirmed or suspected SIV infection. 'Close contact,' is defined as being within a proximity of six feet of someone who has a confirmed case of SIV. An, 'Acute Respiratory Illness,' is defined as the recent onset of at least two of the following things:
- Nasal congestion
- Sore throat
- Cough; with or without a fever or feverishness
Healthcare Worker Recommendations
When interviewing persons who are either suspected of having, or are confirmed with the SIV virus, it is recommended to:
- Keep a distance of at least 6 feet (1.83 m) from the ill person, or use
- Personal protective equipment: fit-tested N95 respirator. If this respirator is unavailable, wear a medical-surgical mask.
When collecting respiratory specimens from an ill confirmed or suspected swine influenza A virus case, the following is recommended:
- Wear a fit-tested disposable N95 respirator or a medical-surgical mask, disposable gloves, gown, and goggles.
- When completed, place all PPE in a biohazard bag for appropriate disposal.
- Wash your hands thoroughly with soap and water or alcohol-based hand gel.
Controlling Infection
Recommended Infection Control for a non-hospitalized patient in an Emergency Room, Clinic, or Home Visit:
Separate the person in a single room, if available, until the person is asymptomatic. If the ill person needs to move to another part of the house, they should wear a mask. The ill person should be encouraged to wash their hands frequently and to follow respiratory hygiene practices. Cups and other utensils that have been used by the ill person should be thoroughly washed with soap and water before they are used by other persons.
Infection Control for hospitalized patients involves the following procedures:
- Use an airborne infection isolation room (AIIR) with negative pressure air handling, if available; otherwise use a single patient room with the door kept closed.
- For suctioning, bronchoscopy, or intubation, use a procedure room with negative pressure air handling.
- Standard, Droplet and Contact precautions for 7 days after illness onset or until symptoms have resolved.
- In addition, personnel should wear N95 respirators when entering the patient room.
Treatment With Antivirals
Treating either confirmed or suspected cases of swine flu with antivirals can include the use of either Zanamivir (Relenza) or Oseltamivir (Tamiflu). Recommendations regarding the use of antivirals can change as information on their susceptibilities becomes available.
Antiviral treatment for confirmed or suspected ill case of swine influenza virus infection may include either oseltamivir (Tamiflu) or zanamivir (Relenza), and the antivirals peramivir (Rapivab) and baloxavir (Xofluza) are also approved to treat influenza today. It is important to initiate the treatment as soon as possible after the onset of symptoms. Close contacts of confirmed and suspected cases of SIV should be monitored for fever and respiratory symptoms for a period of seven days after their last known exposure to a person with a confirmed case of SIV infection.
Dr. Christine Nevin-Woods, executive director of the Pueblo City-County Health Department, has presented a list of actions that people can take to stay healthy during any outbreaks of swine flu. These actions include:
- Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hand cleaners are also effective.
- Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
- Avoid touching your eyes, nose, or mouth. Germs spread that way.
- Try to avoid close contact with sick people.
- Influenza is thought to spread mainly person-to-person through coughing or sneezing of infected people.
- If you are sick, stay home from work or school and limit contact with others to keep from infecting them.
Preparedness and stockpiling may be needed if an illness is near or in your area. Social distancing is implemented to reduce the spread of the illness. Social distancing may be used to prevent large crowds of people from gathering. For example, schools and shopping centers may be closed; sporting events or other special events may be canceled to protect the community from spreading illness.
H1N1 Facts and Statistics
H1N1 flu is also known as swine flu. It's called swine flu because, in the past, the people who caught it had direct contact with pigs. That changed in 2009, when a new virus emerged that spread among people who hadn't been near pigs. Just like the regular flu, swine flu can lead to more serious problems including pneumonia, a lung infection, and other breathing problems. And it can make an illness like diabetes or asthma worse.
- Despite the name, you can't catch swine flu from eating bacon, ham, or any other pork product.
- It's hard to tell whether you have swine flu or seasonal flu because most symptoms are the same. People with swine flu may be more likely to feel nauseous and throw up than people who have seasonal flu. But a lab test is the only way to know for sure.
- Swine flu is contagious, and it spreads in the same way as the seasonal flu. When people who have it cough or sneeze, they spray tiny drops of the virus into the air. If you come in contact with these drops or touch a surface (such as a doorknob or sink) that an infected person has recently touched, you can catch H1N1 swine flu.
- People who have swine flu can be contagious one day before they have any symptoms, and as many as 7 days after they get sick. Kids can be contagious for as long as 10 days.
- The World Health Organization (WHO) declared the H1N1 pandemic over on August 10, 2010. By then, more than 214 countries and overseas territories or communities had reported laboratory confirmed cases of pandemic influenza H1N1 2009, including over 18,000 deaths.
- Because most deaths were never tested, the CDC estimates that 151,700 to 575,400 people died worldwide during the first year the virus circulated, and that in the United States the virus caused about 60.8 million cases, 274,304 hospitalizations, and 12,469 deaths from April 2009 to April 2010.
Frequently Asked Questions
Can you get swine flu from eating pork?
No, you cannot catch H1N1 swine flu from eating properly handled and cooked pork products, since the virus spreads between people through respiratory droplets and contaminated surfaces.
How is H1N1 swine flu different from seasonal flu?
The symptoms are largely the same, though people with swine flu may be more likely to feel nauseous or vomit, and only a lab test can confirm which virus is responsible.
Is there a vaccine for H1N1 swine flu?
Yes, an H1N1 vaccine was developed, and the strain is now commonly included in seasonal flu vaccines, so an annual flu shot offers protection against it.
Who is most at risk of complications from swine flu?
Young children, older adults, pregnant people, and those with chronic conditions such as asthma, diabetes, or weakened immune systems face a higher risk of serious complications.
How can I protect my family from swine flu at home?
Wash hands often, cover coughs and sneezes, clean shared surfaces, keep sick family members separated when possible, and avoid sharing cups and utensils until they recover.
When should someone see a doctor for flu symptoms?
Seek medical care for trouble breathing, chest pain, persistent high fever, confusion, severe or worsening symptoms, or if you are in a high-risk group.
How long should a person with swine flu stay home?
People are generally advised to stay home until symptoms, especially fever, have resolved, since they can remain contagious for about seven days or longer in children.
Is H1N1 still circulating today?
Yes, the H1N1 strain that caused the 2009 pandemic now circulates as one of the regular seasonal flu viruses. The yearly flu vaccine includes protection against it.
Curated and edited by Ian C. Langtree, Founder and Editor-in-Chief, Disabled World. This section is maintained by the Disabled World editorial team. Last updated: