Influenza A (H1N1) (referred to as "swine flu" early on) is a new influenza virus causing illness in people. This new virus was first detected in people in the United States in April 2009 with the 1st case in India being detected on May 16th, 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 this novel H1N1 flu was underway, thus classifying it as Phase 6. This virus was originally referred to as “swine flu” because laboratory testing showed that many of the genes in this new virus were very similar to influenza viruses that normally occur in pigs (swine) in North America. But further study has shown that this new virus is very different from what normally circulates in North American pigs. It has two genes from flu viruses that normally circulate in pigs in Europe and Asia and bird (avian) genes and human genes. Scientists call this a "quadruple reassortant" virus.

The symptoms of novel H1N1 flu virus in people include fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and fatigue, which are quite similar to those of seasonal flu. A significant number of people who have been infected with this virus also have reported diarrhea and vomiting.

•	Remain home at the earliest sign of illness.
•	Minimize contact in the community to the extent possible.
•	Designate a single household family member as caregiver for the patient to minimize interactions with asymptomatic persons.

In most patients swine flu causes a mild disease. Only in certain high risk population is the infection severe. Influenza A (H1N1) is a new virus and one to which most people have no or little immunity and, therefore, this virus could cause more infections than are seen with seasonal flu. Thus the overall vulnerability of the population can play a major role. For example, people with underlying chronic conditions, such as cardiovascular disease, hypertension, asthma, diabetes, rheumatoid arthritis, and several others, are more likely to experience severe or lethal infections. The prevalence of these conditions, combined with other factors such as nutritional status makes swine flu a dangerous infection for these patients to catch.

The following groups are at a higher risk for swine flu related complications -

•	Children less than 5 years old
•	Persons aged 65 years or older
•	Children and adolescents (less than 18 years) who are receiving long-term aspirin therapy and who might be at risk for experiencing Reye syndrome after influenza virus infection
•	Pregnant women
•	Adults and children who have chronic pulmonary, cardiovascular, hepatic, hematological, neurologic, neuromuscular, or metabolic disorders
•	Adults and children who have immunosuppression (including immunosuppression caused by medications or by HIV)
•	Residents of nursing homes and other chronic-care facilities.

If you see any of the following emergency warning signs, you should take your child to hospital immediately:

•	Fast breathing or trouble breathing
•	Bluish or gray skin color
•	Not drinking enough fluids
•	Severe or persistent vomiting
•	Not waking up or not interacting
•	Being so irritable that the child does not want to be held
•	Flu-like symptoms improve but then return with fever and worse cough