Swine Influenza Introduction
Swine influenza (also called swine flu, hog flu, and pig flu) refers to influenza caused by the influenza virus endemic in pigs (swine). Strains endemic in swine are called swine influenza virus (SIV). The 2009 flu outbreak in humans that is widely known as "swine flu" is due to a new strain of influenza A virus subtype H1N1 that was produced by a reassortment from one strain of human influenza virus, one strain of avian influenza virus, and two separate strains of swine influenza virus. The origins of this new strain are unknown, and the World Organization for Animal Health (OIE) reports that this strain has not been isolated in swine. It passes with apparent ease from human to human.
The National Health Service (NHS) have stated the following:
"Swine flu is a respiratory disease and has some elements of a virus found in pigs. There are no evidence of this disease circulating in pigs in the UK and scientists are investigating its origins.
Swine flu has been confirmed in a number of contries and it is speading from human to human, which could lead to what is referred to as a pandemic flu outbreak."
Pandemic flu is different from ordinary flu because it's a new flu virus that appears in humans and spreads very quickly from person to person worldwide. The World Health Organization (WHO) is closely monitoring cases of Swine flu globally to see whether this virus develops into a pandemic.
Because it's a new virus, no one will have immunity to it and everyone could be at risk of catching it. This includes healthy adults as well as older people, young children and those with existing medical conditions.
Symptoms of H1N1
According to the Centers for Disease Control and Prevention (CDC), in humans the symptoms of H1N1 (swine flu) are similar to those of influenza and of influenza-like illness in general. Symptoms include fever, coughing, sore throat, body aches, headache, chills and fatigue. The 2009 outbreak has shown an increased percentage of patients reporting diarrhea and vomiting.
How H1N1 spreads
The main way that H1N1 seems to spread is by close person-to-person contact. The virus that causes H1N1 is thought to be transmitted most readily by respiratory droplets (droplet spread) produced when an infected person coughs or sneezes. Droplet spread can happen when droplets from the cough or sneeze of an infected person are propelled a short distance (generally up to 3 feet) through the air and deposited on the mucous membranes of the mouth, nose, or eyes of persons who are nearby. The virus also can spread when a person touches a surface or object contaminated with infectious droplets and then touches his or her mouth, nose, or eye(s). In addition, it is possible that the H1N1 virus might spread more broadly through the air (airborne spread) or by other ways that are not now known. H1N1 cannot be spread by pork products, since the virus is not transmitted through food. H1N1 swine flu in humans is most contagious during the first five days of the illness although some people, most commonly children, can remain contagious for up to ten days.
What does "close contact" mean?
In the context of H1N1, close contact means having cared for or lived with someone with H1N1 or having direct contact with respiratory secretions or body fluids of a patient with H1N1. Examples of close contact include kissing or hugging, sharing eating or drinking utensils, talking to someone within 3 feet, and touching someone directly. Close contact does not include activities like walking by a person or briefly sitting across a waiting room or office.