What is it?

• Novel H1N1 flu, popularly known as swine flu, is a respiratory infection caused by an influenza virus first recognized in spring 2009. The new virus, which is officially called swine influenza A (H1N1), contains genetic material from human, swine and avian flu viruses.
• Technically, the term "swine flu" refers to influenza in pigs. Occasionally, pigs transmit influenza viruses to people, mainly hog farm workers and veterinarians. Less often, someone infected occupationally passes the infection to others. You can't catch swine flu from eating pork.
• Unlike typical swine flu, H1N1 flu spreads quickly and easily. In June 2009, when the infection's spread had been verified worldwide, the World Health Organization declared H1N1 flu a global pandemic.
• An H1N1 vaccine has been developed for the 2009-10 flu season.

Symptoms

Swine flu symptoms in humans are similar to those of infection with other flu strains:

• Fever
• Cough
• Sore throat
• Body aches
• Headache
• Chills
• Fatigue
• Diarrhoea
• Vomiting

Swine flu symptoms develop three to five days after you're exposed to the virus and continue for about eight days, starting one day before you get sick and continuing until you've recovered.

Causes

Influenza viruses infect the cells lining your nose, throat and lungs. The virus enters your body when you inhale contaminated droplets or transfer live virus from a contaminated surface to your eyes, nose or mouth on your hand.

Risk factors

Because novel H1N1 virus is new, everyone is at some risk. Health care workers who provide direct patient care are at particular risk of catching H1N1 flu. College students and children in school and child care are also at high risk. Children typically pick up the virus in the classroom and pass it to other members of the household.

Complications

Influenza complications include:

• Worsening of chronic conditions, such as heart disease, diabetes and asthma
• Pneumonia
• Respiratory failure

Severe complications of human swine flu H1N1 seem to develop and progress rapidly.

References:

http://www.cdc.gov/h1n1flu/sick.htm

http://www.flu.gov/about_the_flu/h1n1/

http://www.medicinenet.com/swine_flu/article.htm

https://en.wikipedia.org/wiki/Influenza_A_virus_subtype_H1N1

https://www.nlm.nih.gov/medlineplus/h1n1fluswineflu.html