Swine Flu: Symptoms, Prevention and Treatment


Swine Flu: Symptoms, Prevention and Treatment

1Rathore K.S., 1Chauhan Priyanka, 1Sharma Surabhi, 1Rathore Savita, 1Vinod Kanwar, 2Nema R.K., 3Sisodia S.S.

1B.N.Girls College of Pharmacy, Udaipur-Raj.313002

2Rishiraj College of Pharmacy, Indore-Mp

3BN Pg College of Pharmacy, Udaipur


Swine flu (swine influenza) is a respiratory disease caused by viruses (influenza viruses known as H1N1) that infect the respiratory tract of pigs and result in nasal secretions, a barking-like cough, decreased appetite, and listless behavior. Swine flu produces most of the same symptoms in pigs as human flu produces in people. Swine flu can last about one to two weeks in pigs that survive. Swine influenza virus was first isolated from pigs in 1930 in the U.S. and has been recognized by pork producers and veterinarians to cause infections in pigs worldwide.

In a number of instances, people have developed the swine flu infection when they are closely associated with pigs (for example, farmers, pork processors), and likewise, pig populations have occasionally been infected with the human flu infection. In most instances, the cross-species infections (swine virus to man; human flu virus to pigs) have remained in local areas and have not caused national or worldwide infections in either pigs or humans. Unfortunately, this cross-species situation with influenza viruses has had the potential to change.

Investigators think the 2009 swine flu strain, first seen in Mexico, should be termed novel H1N1 flu since it is mainly found infecting people and exhibits two main surface antigens, H1 (hemagglutinin type 1) and N1 (neuraminidase type1). Recent investigations show the eight RNA strands from novel H1N1 flu have one strand derived from human flu strains, two from avian (bird) strains, and five from swine strains.

Influenza, commonly called “the flu,” is an illness caused by RNA viruses that infect the respiratory tract of many animals, birds, and humans. In most people, the infection results in the person getting fever, cough, headache, and malaise (tired, no energy); some people also may develop a sore throat, nausea, vomiting, and diarrhoea. The majority of individuals has symptoms for about one to two weeks and then recovers with no problems. However, compared with most other viral respiratory infections, such as the common cold, influenza (flu) infection can cause a more severe illness with a mortality rate (death rate) of about 0.1% of people who are infected with the virus.

The history of swine flu (H1N1) in humans

In 1976, there was an outbreak of swine flu at Fort Dix. This virus is not the same as the 2009 outbreak, but it was similar insofar as it was an influenza A virus that had similarities to the swine flu virus. There was one death at Fort Dix. The government decided to produce a vaccine against this virus, but the vaccine was associated with neurological complications (Guillain-Barré syndrome) and was discontinued. Some individuals speculate that formalin, used to inactivate the virus, may have played a role in the development of this complication in 1976.

There is no evidence that anyone who obtained this vaccine would be protected against the 2009 swine flu. One of the reasons it takes a few months to develop a new vaccine is to test the vaccine for safety to avoid the complications seen in the 1976 vaccine. New vaccines against any flu virus type are usually made by growing virus particles in eggs. A serious side effect (allergic reaction such as swelling of the airway) to vaccines can occur in people who are allergic to eggs; these people should not get flu vaccines. Individuals with active infections or diseases of the nervous system are also not recommended to get flu vaccines.

Swine flu is caused by The H1N1 or “swine flu” virus, which first appeared in April 2009, has gone on to become a worldwide “pandemic.” H1N1 influenza is a virus that causes illness in people and spreads from one person to another in the same way as the common flu. Detected first in April 2009 in Mexico, the disease soon spread across different countries in the world and was declared the swine flu pandemic by the World Health Organization in June 2009. After conducting several laboratory tests, it was determined that the virus responsible for swine influenza was similar to those found in pigs, thus prompting scientists to name it the swine (pig) flu.

Illness caused by the swine flu virus ranges from mild to extreme in different cases. While many of the patients have recovered even without medical treatment, the virus has also caused a number of deaths as well as hospitalizations, which has made it a matter of grave concern for the authorities. Any person, irrespective of age or sex can contract the disease but the risk seems bigger in children and old age people as also in people with lower immunity levels, pregnant women and people suffering from heart disease, kidney ailment or asthma. A person displaying swine flu symptoms should consult a medical practitioner immediately and get himself tested.

 Link between Guillain-Barre syndrome and swine flu vaccines

Guillain Barre Syndrome (GBS), a rare neurological disorder, was an identified risk with swine flu vaccines used in the United States in 1976 – it is thought that one extra case of GBS occurred with every 100,000 doses of vaccine. The reason why the 1976 vaccine increased the risk of GBS remains unknown. Many studies have looked at whether other flu vaccines used since 1976 carry a risk of GBS and no robust evidence of a causal link has been found. No cases of GBS have been found in the clinical trials of H5N1 vaccines.

Most illnesses caused by the swine flu epidemic were of a mild nature and patients recovered even without or with very little medication required. However, recently the virus has caused a lot of panic after a number of deaths were reported. The swine flu virus is extremely contagious and spreads through coughing and sneezing or when a person touches a contaminated surface and then touches his nose or mouth. The symptoms of swine flu are very similar to those of the seasonal flu such as high fever, runny nose, loss of appetite, cough, sore throat etc.

Infectious Period

Persons with swine influenza A (H1N1) virus infection should be considered potentially contagious for up to 7 days following illness onset. Persons who continue to be ill longer than 7 days after illness onset should be considered potentially contagious until symptoms have resolved. Children, especially younger children, might potentially be contagious for longer periods. The duration of infectiousness might vary by swine influenza A (H1N1) virus strain. Non-hospitalized ill persons who are a confirmed or suspected case of swine influenza A (H1N1) virus infection are recommended to stay at home (voluntary isolation) for at least the first 7 days after illness onset except to seek medical care.

Reason for why swine flu (H1N1) now infecting humans

Swine flu viruses may mutate (change) so that they are easily transmissible among humans. Many researchers now consider that two main series of events can lead to swine flu (and also avian or bird flu) becoming a major cause for influenza illness in humans.

First, the influenza viruses (types A, B, C) are enveloped RNA viruses with a segmented genome; this means the viral RNA genetic code is not a single strand of RNA but exists as eight different RNA segments in the influenza viruses. A human (or bird) influenza virus can infect a pig respiratory cell at the same time as a swine influenza virus; some of the replicating RNA strands from the human virus can get mistakenly enclosed inside the enveloped swine influenza virus. For example, one cell could contain eight swine flu and eight human flu RNA segments. The total number of RNA types in one cell would be 16; four swine and four human flu RNA segments could be incorporated into one particle, making a viable eight RNA segmented flu virus from the 16 available segment types.

Various combinations of RNA segments can result in a new subtype of virus (known as antigenic shift) that may have the ability to preferentially infect humans but still show characteristics unique to the swine influenza virus. It is even possible to include RNA strands from birds, swine, and human influenza viruses into one virus if a cell becomes infected with all three types of influenza (for example, two bird flu, three swine flu, and three human flu RNA segments to produce a viable eight-segment new type of flu viral genome). Formation of a new viral type is considered to be antigenic shift; small changes in an individual RNA segment in flu viruses are termed antigenic drift and result in minor changes in the virus. However, these can accumulate over time to produce enough minor changes that cumulatively change the virus’ antigenic makeup over time (usually years).

Second, pigs can play a unique role as an intermediary host to new flu types because pig respiratory cells can be infected directly with bird, human, and other mammalian flu viruses. Consequently, pig respiratory cells are able to be infected with many types of flu and can function as a “mixing pot” for flu RNA segments. Bird flu viruses, which usually infect the gastrointestinal cells of many bird species, are shed in bird feces. Pigs can pick these viruses up from the environment and seem to be the major way that bird flu virus RNA segments enter the mammalian flu virus population.

Swine flu emergency

Children should get urgent medical attention if they have fast breathing or trouble breathing, have bluish or gray skin color, are not drinking enough fluid, are not waking up or not interacting, have severe or persistent vomiting, are so irritable that the child doesn’t want to be held, have flu-like symptoms that improve but then return with fever and a worse cough, have fever with a rash, or have fever and then have a seizure or sudden mental or behavioral change. Adults should seek urgent medical attention if they have trouble breathing or shortness of breath, pain or pressure in the chest or abdomen, sudden dizziness, confusion, severe or persistent vomiting, or flu-like symptoms that improve, but then come back with worsening fever or cough.

Swine flu precautions

Swine flu or the H1N1 virus is a type A influenza, which is normally reported in pigs and has rarely affected humans in the past. A few cases that had been reported in people, who had been around pigs, over the past few years, were of a mild nature. However, in April 2009, swine flu started to affect thousands of persons around the world, just days after being reported in a Mexican village, and thus prompted the World Health Organization to declare it a pandemic.

It is advisable to avoid travelling to affected countries and stay away from crowded places. The easily available swine flu mask can also protect from the virus. While there are no vaccines available that can guard against swine flu, certain precautions can ensure protection from this deadly disease.

Swine Flu High Risk Groups –

Swine flu high risk groups, people who are thought to be at risk for serious, life-threatening infections, are a little different and can include:

  • pregnant women
  • people with chronic medical problems, such as chronic lung disease, like asthma, cardiovascular disease, diabetes, and immunosuppression
  • children and adults with obesity

It is already known that you are particularly at risk if you have:

  • chronic (long-term) lung disease,
  • chronic heart disease,
  • chronic kidney disease,
  • chronic liver disease,
  • chronic neurological disease (neurological disorders include motor neurone disease, multiple sclerosis and Parkinson’s disease),
  • immunosuppression (whether caused by disease or treatment) or
  • diabetes mellitus.

Also at risk are:

  • patients who have had drug treatment for asthma within the past three years,
  • pregnant women,
  • people aged 65 and older, and
  • young children under five.
  • It is vital that people in these higher-risk groups who catch swine flu get antivirals and start taking them as soon as possible.

The complications of swine flu

One of the most common complications of any type of flu is a secondary bacterial chest infection, such as bronchitis (infection of the airways).This can become serious and develop into pneumonia. A course of antibiotics will usually cure this, but the infection sometimes becomes life-threatening. Other rare complications include:

  • tonsillitis,
  • otitis media (a build-up of fluid in the ear),
  • septic shock (infection of the blood that causes a severe drop in blood pressure),
  • meningitis (infection in the brain and spinal cord), and
  • encephalitis (inflammation of the brain).

Swine flu symptoms – Know it to avoid it

As the H1N1 Influenza spreads its wings over different parts of the globe, it is extremely important to be familiar with the symptoms of swine flu so that the disease can be detected at an early stage and preventive measures can be taken to check its rise.

If you or any of the persons around you are suffering from fever in excess of 100.4 °F as well as any of the other below mentioned H1N1 influenza symptoms, then you may have contracted swine flu.

  • The most common of all swine flu symptoms is high body temperature, in excess of 38 °C/100.4 °F.
  • Swine flu (swine influenza) is a respiratory disease caused by viruses (influenza viruses) that infect the respiratory tract of pigs and result in nasal secretions, a barking-like cough, decreased appetite, and listless behavior.
  • Headache
  • Loss of appetite
  • Stinging throat
  • Runny nose
  • Extreme tiredness (fatigue)
  • Aching muscles
  • dyspnea
  • chills
  • Loss of energy, vomiting
  • Diarrhea
  • myalgia
  • influenza-like illness (fever, cough or sore throat)
  • mild respiratory illness (nasal congestion, rhinorrhea) without fever and occasional severe disease also has been reported
  • Conjunctivitis
  • Sudden, persistent cough

While these symptoms can be considered an indication of swine flu, the symptoms have also been reported in people suffering from other diseases. Therefore, despite having these symptoms, the patient or the doctor cannot be sure of swine flu until the test reports confirm the same. The disease is especially dangerous for children, where it can result in neurological disorders or alterations in the state of mind. It is still not clear why the situation occurs, but if not treated, it can prove to be fatal.

As with any sort of flu, how bad the symptoms are and how long they last will vary depending on treatment and individual circumstances. Most cases reported in the UK to date have been relatively mild, with affected people starting to recover within a week.

You can go back to school or work when you are feeling well and are no longer infectious. Adults are most infectious soon after they develop symptoms and remain infectious while their symptoms continue, which is usually for up to five days. They can normally return to work within seven days. In children, symptoms continue for up to seven days and they can normally return to school within 10 days.

Diagnosis of swine flu (H1N1)

Swine flu is presumptively diagnosed clinically by the patient’s history of association with people known to have the disease and their symptoms listed above. Usually, a quick test (for example, nasopharyngeal swab sample) is done to see if the patient is infected with influenza A or B virus. Most of the tests can distinguish between A and B types. The test can be negative (no flu infection) or positive for type A and B. If the test is positive for type B, the flu is not likely to be swine flu (H1N1). If it is positive for type A, the person could have a conventional flu strain or swine flu (H1N1). However, the accuracy of these tests has been challenged, and the U.S. Centers for Disease Control and Prevention (CDC) has not completed their comparative studies of these tests. However, a new test developed by the CDC and a commercial company reportedly can detect H1N1 reliably in about one hour; as of October 2009, the test is only available to the military.

Swine flu (H1N1) is definitively diagnosed by identifying the particular antigens associated with the virus type. In general, this test is done in a specialized laboratory and is not done by many doctors’ offices or hospital laboratories. However, doctors’ offices are able to send specimens to specialized laboratories if necessary. Because of the large number of novel H1N1 swine flu cases (as of October 2009, the vast majority of flu cases [about 99%] are due to novel H1N1 flu viruses), the CDC recommends only hospitalized patients’ flu virus strains be sent to reference labs to be identified.

Points to remember

Swine flu spreads through an infected person’s secretion released at the time of sneezing or coughing. People with symptoms of swine flu can pass on the disease to others from one day before to seven days after getting the infection. The virus can also contaminate surfaces and infect a healthy person if he happens to touch his nose or mouth after touching the dirty surface.

Swine Flu Test

Swine flu or the H1N1 virus is a disease that has spread in a large number of countries around the world in a very short span of time. It is the alarming rate with which the disease spreads that has worried experts, who are trying to check its rise. Swine flu symptoms are a lot like the symptoms of seasonal flu, which makes it extremely difficult to distinguish between the two without carrying out prescribed swine flu tests in the laboratories set-up especially for the purpose.

Steps to ensure swine flu protection

Simply by following the simple guidelines here, you should at least lessen your chances of becoming sick with Swine Flu. Like in the case of seasonal flu, the below mentioned precautions can help protect you against the H1N1 virus:

  • Avoid going near people with swine flu symptoms.
  • Avoid going to crowded places.
  • Cover your mouth and nose properly with a tissue while sneezing or coughing and dispose off the infected tissue in a proper way, away from the reach of other people.
  • It is recommended to get a seasonal flu vaccination. Though it may not prevent you from swine flu, it won’t do any harm.
  • Keep good hygiene and wash your hands regularly with soap and warm water. It is advisable to use an alcohol based hand wash. Use the antibacterial soaps to cleanse your hands. Wash them often, for at least 15 seconds and rinse with running water.
  • Get enough sleep -Try to get 8 hours of good sleep every night to keep your immune system in top flu-fighting shape.
  • Drink sufficient water-Drink 8 to10 glasses of water each day to flush toxins from your system and maintain good moisture and mucous production in your sinuses.
  • Sick people should stay home to avoid passing on the disease to others.
  • Always wear the swine flu mask when travelling to crowded places.
  • Disposing of dirty tissues promptly and carefully.
  • Cleaning hard surfaces, such as door handles, often and thoroughly using a normal cleaning product.
  • Carry anti-viral medicines with you.
  • If you feel sick or show any of the swine flu symptoms, consult your doctor immediately and get yourself tested for the virus.
  • Boost your immune system-Keeping your body strong, nourished, and ready to fight infection is important in flu prevention. So stick with whole grains, colorful vegetables, and vitamin-rich fruits.
  • Keep informed-The government is taking necessary steps to prevent the pandemic and periodically release guidelines to keep the pandemic away. Please make sure to keep up to date on the information and act in a calm manner.
  • Do not risk it. If you are experiencing influenza like symptoms, simply stay home. Since these symptoms mirror regular cold and influenza symptoms, it is better to be safe than sorry.
  • Find out how to cough and sneeze. Here’s the deal – cough or sneeze into the interior of your elbow on your arm. This is the only way to keep from spreading germs to your hands and to everything you touch.
  •  A little hand sanitizer goes a long, long way. Simply have a tube of hand sanitizer with you at all time. This way you can continually clean your hands.
  •  Be wary of public places. Door handles and even ink pens are breeding grounds for germs. Avoid touching them at all costs.
  •  Be cautious on airplanes, trains and buses. The close quarters of an aeroplane is a place where germs like the swine flu pathogen lurk so protect yourself.
  • Wash your vegetables and fruit entirely. Purchase your vegetables and vegetables locally if you can. Wash them with water and soak them to extend the effectiveness.
  •  Go to your doctor. If you are experiencing any flu like symptoms you should see your doctor at once. As stated earlier, only your health practitioner can diagnose your particular strain of the flu.

Swine flu treatment – Don’t panic

Although swine flu has been spreading at a rapid pace in India as well as in most other countries of the world, it must be remembered that swine flu is a curable disease and can be effectively cured if treated properly. As is the case in seasonal flu, the treatment of swine flu includes-

  • Proper rest and care.
  • A swine flu patient must not be involved in too much strenuous work and
  • Should drink plenty of liquids to keep himself hydrated.
  • Alcohol and tobacco are strictly prohibited for swine flu patients and medicines such as paracetamol can be taken to get relief from fever and muscle pain.
  • In extreme cases, antiviral drugs and hospitalization may be required. The best way, however, to avoid any emergency situation is to contact your doctor immediately if you suspect of having swine flu. If you happen to recently travel to an infected region or have been around those infected with the virus, then contact your doctor and take all preventive steps to ensure your safety. Remember, early detection will lead to proper treatment being administered and could mean the difference between life and death.
  • Keep the patient in a separate room, away from other members of the household.
  • Everyone in the house should wash their hands regularly and wear a mask while going near the patient.
  • The members of the house should also take antiviral drugs such as tamiflu, if the doctor prescribes it.
  • Children should not be given medicines such as aspirin for its tendency to cause neurological disorders.

Remember, prevention is better than cure

Although no swine flu vaccine is available in the market to ensure safety against the disease, certain medicines, which can cure the disease, are available. This virus is resistant to the antiviral medications amantadine (Symmetrel) and rimantadine (Flumadine). There are 2 medications in the market that have been shown to be effective against swine flu zanamivir (Relenza) and oseltamivir (Tamiflu). These medicines have to be administered within 2 days of the onset of symptoms (which last about a week), and are said to shorten the duration of symptoms by about 2 days. Because early detection is vital for the efficacy of these drugs, rapid detection is necessary. Many manufacturers are currently working on versions of a rapid swine flu test to allow early detection in minutes, as opposed to days as is with traditional virus testing.

To reproduce and spread, a virus has to enter your body, take over healthy cells and force them to make copies of itself. Relenza stops the release of new copies of the virus from infected cells in the lungs. This slows the spread of the virus, reduces the symptoms and length of time that you feel unwell for and makes it harder for the virus to spread to other people. Relenza should first be taken within 48 hours of symptoms appearing in adults (36 hours in children). It works better the earlier you start taking it.

To reproduce and spread, a virus has to enter your body, take over healthy cells and force them to make copies of it. Tamiflu stops the flu virus entering your cells and blocks the release of new copies of the virus. This slows the spread through your body, reduces the symptoms and the length of time that you feel unwell for and makes it harder for the virus to spread to other people. Tamiflu should first be taken within 12 to 48 hours of symptoms appearing. It works better the earlier you start taking it.

Relenza reduces the duration of flu symptoms by one-and-a-half days on average. Tamiflu reduces the duration of symptoms by up to two days.

Vaccine for H1N1 swine flu

The best way to prevent novel H1N1 swine flu would be the same best way to prevent other influenza infections, and that is vaccination. The CDC has multiple recommendations for vaccination based on who should obtain the first doses when the vaccine becomes available (to protect the most susceptible populations) and according to age groups. The CDC based the recommendations on data obtained from vaccine trials and infection reports gathered over the last few months. The current (October 2009) vaccine recommendations from the CDC say the following groups should get the vaccine as soon as it is available:

  • pregnant women,
  • people who live with or provide care for children younger than 6 months of age,
  • health-care and emergency medical services personnel,
  • people between 6 months and 24 years of age, and

People from the ages of 25 through 64 who are at higher risk because of chronic health disorders such as asthma, diabetes, or a weakened immune system.

Currently, the CDC is stating that people ages 10 and above are likely to need only one vaccine shot to provide protection against novel H1N1 swine flu and further suggest that these shots will be effective in about 76% of people who obtain the vaccine. New vaccine trial data showed that healthy adults produce protective antibodies in about 98% of people in 21 days. Unfortunately, the vaccine shot in children ages 6 months to 9 years of age is not as effective as it is in older children and adults. Consequently, the CDC currently recommends that for ages 6 months up to and including 9 years of age, the children obtain two shots of the novel H1N1 vaccine, the second shot 21 days after the first shot.

Pregnant women are strongly suggested to get vaccinated as stated above. Although some vaccine preparations (multidose vials) contain low levels of thimerosal preservative (a mercury-containing preservative), the CDC still considers the vaccine safe for the fetus and mother. However, some vaccine preparations that are in single-dose vials will not have thimerosal preservative, so those pregnant individuals who are concerned about thimerosal can get this vaccine preparation when it is available.

Another type of vaccine (currently named Influenza A [H1N1] 2009 Monovalent Vaccine Live, Intranasal) has been made available during the first week in October 2009. It is a live attenuated novel H1N1 flu vaccine that contains no thimerosal, is produced by MedImmune, LLC, and is sprayed into the nostrils. This vaccine is only for healthy people 2-49 years of age, and some data suggest that it is less effective in generating an immune response in adults than the vaccine injection. The dosing schedule is as follows:

  • Children 2-9 years of age should receive two doses (0.1 ml in each nostril; total equals 0.2 ml per dose) — the second dose should be given the same way about one month after the first dose
  • Children, adolescents and adults, 10-49 years of age should receive one dose — (0.1 ml in each nostril; total equals 0.2 ml per dose)

The following is a list of the CDC-approved H1N1 vaccines and the companies that name and manufacture them as of 10/29/09:

  • Influenza A (H1N1) 2009 Monovalent Vaccine by CSL Limited
  • Influenza A (H1N1) 2009 Monovalent Vaccine by Novartis
  • Influenza A (H1N1) 2009 Monovalent Vaccine by Sanofi Pasteur
  • Influenza A (H1N1) 2009 Monovalent Vaccine Live, Intranasal by MedImmune, LLC

The following vaccination schedule is recommended in the UK:


  • For all children aged from six months to nine years: – two half doses (0.25ml each) given with a minimum of three weeks between doses.
  • For individuals aged 10-59: – one dose (0.5ml) given.
  • For individuals aged 60 years and over: – one dose given (this advice will be reviewed when more data become available).
  • For individuals aged 10 years and over with weakened immune systems:- two doses (0.5ml each) given with a  minimum of three weeks between doses.


  • For children aged from six months and adults:- two doses (0.5ml each) given with a  minimum of three weeks between doses. 
  • This dosage schedule is based on advice given by the Joint Committee on Vaccination and Immunisation, following consideration of clinical data available on the vaccines. The dosage and recommendations will be kept under review as more clinical data become available.

Recommendations for public health personnel

For interviews of healthy individuals (i.e. without a current respiratory illness), including close contacts of cases of confirmed swine influenza virus infection, no personal protective equipment or antiviral chemoprophylaxis is needed. See section on antiviral chemoprophylaxis for further guidance. For interviews of an ill, suspected or confirmed swine influenza A virus case, the following is recommended:

  • Keep a distance of at least 6 feet from the ill person; or
  • Personal protective equipment: fit-tested N95 respirator [if unavailable, wear a medical (surgical mask)].

For collecting respiratory specimens from an ill confirmed or suspected swine influenza A virus case, the following is recommended:

  • Personal protective equipment: fit-tested disposable N95 respirator [if unavailable, wear a medical (surgical mask)], disposable gloves, gown, and goggles.
  • When completed, place all PPE in a biohazard bag for appropriate disposal.
  • Wash hands thoroughly with soap and water or alcohol-based hand gel.

Recommended Infection Control for a non-hospitalized patient (ER, clinic or home visit):

Separation from others in single room if available until 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 hand frequently and follow respiratory hygiene practices. Cups and other utensils used by the ill person should be thoroughly washed with soap and water before use by other persons.

When crowded settings or close contact with others cannot be avoided, the use of facemasks or respirators in areas where transmission of swine influenza A (H1N1) virus has been confirmed should be considered as follows:

  • Whenever possible, rather than relying on the use of facemasks or respirators, close contact with people who might be ill and being in crowded settings should be avoided.
  • Facemasks should be considered for use by individuals who enter crowded settings, both to protect their nose and mouth from other people’s coughs and to reduce the wearers’ likelihood of coughing on others; the time spent in crowded settings should be as short as possible.
  • Respirators should be considered for use by individuals for whom close contact with an infectious person is unavoidable. This can include selected individuals who must care for a sick person (e.g., family member with a respiratory infection) at home.

The types of face masks and respirators

Unless otherwise specified, the term “facemasks” refers to disposable masks cleared by the U.S. Food and Drug Administration (FDA) for use as medical devices. This includes facemasks labeled as surgical, dental, medical procedure, isolation, or laser masks.

Such facemasks have several designs-

  • One type is affixed to the head with two ties, conforms to the face with the aid of a flexible adjustment for the nose bridge, and may be flat/pleated or duck-billed in shape.
  • Another type of facemask is pre-molded, adheres to the head with a single elastic band, and has a flexible adjustment for the nose bridge.
  • A third type is flat/pleated and affixes to the head with ear loops. Facemasks cleared by the FDA for use as medical devices have been determined to have specific levels of protection from penetration of blood and body fluids.
  • Unless otherwise specified, “respirator” refers to an N95 or higher filtering facepiece respirator certified by the U.S. National Institute for Occupational Safety and Health (NIOSH).

Take note of what you’ve learned here about the swine flu. Look after yourself and protect yourself as best as you possibly can.


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