The classical swine flu virus an influenza type A (H1N1) virus was first isolated from a pig in 1930. Swine flu viruses cause high level of illness, but low death rates in pigs. Like all influenza viruses, swine flu viruses change constantly. Pigs can also be infected by avian influenza and human influenza viruses. When influenza viruses from different species infect pigs, the viruses can reassort (i.e. swap genes) and new viruses that are a mix of swine, human and/or avian influenza viruses can emerge.

Suspect Case:

A suspect case is defined as an individual with fever (temperature 100.4°F/ 38°C) and one or more of the following manifestations- cough, sore throat, or shortness of breath.

Probable Case:

A probable case is defined as an individual with an influenza test that is positive for influenza A, but is unsubtypable by reagents used to detect seasonal influenza virus infection or an individual who died of an unexplained acute respiratory illness.

Confirmed Case:

A confirmed case is defined as an individual who is confirmed in the laboratory with PCR or virus culture for pandemic influenza virus 2009.


A cluster of pandemic influenza 2009 is defined as two or more suspect, probable or confirmed cases of pandemic influenza 2009 found at a time in a localised area, having evidence of transmission among them.



Swine flu, or H1N1, is a type A influenza virus that can infect humans. It is similar to the seasonal influenza virus, but can be more severe in people who may be at high risk because of a preexisting condition. According to the Centres for Disease Control, risk factors include chronic medical conditions such as diabetes, heart disease, and asthma.

Aches and Fevers:

Swine flu is severe body aches, this can include muscle weakness and difficulty standing up or walking. Headaches in combination with body aches are also quite common.

Upper-Respiratory Symptoms:

A common element of swine flu is upper-respiratory symptoms. These can be similar to a cold, except more severe. A runny or stuffy nose combined with head congestion is typically present. Itchy or watery eyes may also be a symptom.


Feelings of general malaise or weakness are common with swine flu, as is overall discomfort. Many people infected with the virus are tired and too weak to complete most normal day-to-day activities, and may sleep longer and more often than usual. Staying home and getting plenty of rest is the best way to fully recover from swine flu.


In some cases of swine flu, people experience gastrointestinal effects. These can range from stomachaches and cramping to nausea and vomiting, and diarrhoea. Swine flu may be confused with food poisoning because of the symptoms of stomach pain and Diarrhoea .

Signs of Swine Flu
Signs of Swine Flu

Warning signs:

Other signs to watch for may indicate that swine flu is developing into a secondary medical condition that can be serious or life- threatening. Because swine flu involves the respiratory tract, there is a risk for developing pneumonia, respiratory failure, and bronchitis.

According to the Centres for Disease Control and Prevention (CDC), in humans the symptoms of the 2009 "swine flu" H1N1 virus are similar to those of influenza and of influenza-like illness in general. Symptoms include fever, cough, sore throat, body aches, headache, chills and fatigue.


There currently is no vaccine to protect humans against the H1N1 flu virus. The following tips will help you prevent flu infections such as the common flu and the H1N1 flu.  

  1. Wash your hands often with soap and water, especially before eating and after sneezing or coughing.  
  2. You can also use an alcohol gel product available over the counter, which is also effective in protecting against flu.  
  3. When you cough or sneeze, cover your mouth and nose with your elbow or sleeve. Or use a tissue and be sure to throw away the tissue after use.
  4.  Wash your hands after you sneeze or cough.  
  5. Try to avoid close contact with sick people. Avoid touching your eyes, nose, or mouth. Germs spread this way. 
  6. Try to stay in good general health. Get plenty of sleep, be physically active, manage your stress, drink plenty of fluids, and eat nutritious food.