A Virus is a very small organism which can only be viewed under the electron microscope.

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1 Pandemic Influenza Fact Sheet What is a Virus? A Virus is a very small organism which can only be viewed under the electron microscope. Properties of viruses Although they are very small, they are live organisms. They have genetic material which is well protected by protein coat. Some of them even have another protective coat called envelope. Viruses cannot grow outside the living cell. For the production of new viruses they need to enter the host cell. After entry into the host cell, they utilise cellular materials to produce new viruses which later move out of the cell and spread to infect another cell. The infected host cell gets disrupted by the virus. If viruses infect many cells in the host tissue, the function of affected organ is disturbed and infected person suffers from the illness. During the life cycle of the virus inside the host cell, the genetic material of parent virus is copied. The copied genetic materials were packed up by newly formed protein coat and new viruses are produced again. One of the amazing properties of viruses is its ability to adapt to the environment very rapidly by changing their genetic material. This is one of the reasons why viruses circulate in different hosts and environment. What is Influenza A? Influenza is a virus which can infect human, pigs, horses and birds. It has different types of influenza named type A, B, C and D. Influenza virus can also change its genetic material during copying process or the assembly process. Because of changes in the genetic material, different influenza viruses are circulating in their host. Why do we call Influenza A- H1N1? Different influenza viruses developed according to their genetic changes. We name them by using the initials of two spikes like molecules present on the surface of influenza. H stands for Haemagglutin which is responsible for entry of the virus into the host cell. Without H spike, influenza virus cannot enter the host cell.

2 N stands for Neuraminidase which is responsible for release of newly assembled influenza viruses from infected cell so that they can enter another host cell and thereby spread infection in the tissue or organ. Without N newly formed influenza viruses cannot spread to another cell. There are 16 different H and 9 different N molecules of influenza type A viruses presently identified by scientists. Influenza A viruses are named according to their respective H and N molecules; for example, H1N1, H5N1 etc. Influenza A H1N1 means, influenza type A virus which has H molecule No. 1 and N molecule No. 1 on their surfaces. Bird Influenza: All influenza H 1 to 16 and N 1 to 9 are circulating in the migratory water birds. Swine Influenza: Only 2 different H (H1 and H3) and 2 different N (N1 and N2) types: of influenza viruses are circulating in the pigs. Human Influenza: Only H1, H2, H3 and N1 and N2 types of influenza viruses are circulating in Human Beings. Equine Influenza: H3, H7 and N7, N8 types of influenza viruses are circulating in human. Why new Influenza A H1N1 is called pandemic? Influenza A H1N1 is a newly found influenza virus to which all humans have no immunity. It is developed from genetic rearrangements between human, bird and pig influenza viruses. Although it is new, the virus adapted to human very rapidly and behaved like human influenza. Because we never met this new Influenza A-H1N1, human suffers flu like symptoms before we can fight back the virus by our immune system. Our immune system was ambushed by new enemy we never face before. Because of its rapid spread across the world, the World Health Organisation (WHO) announced pandemic Influenza alert in June How is it transmitted? The spread of the virus is possible by virus laden droplets produced from nose, throat and lung of the infected person. If another person inhales the virus laden droplet, his or

3 her lungs will also be infected by the virus. Close contact (within 2-meters) with infected person increases the chances of infection. Another possible transmission of influenza is through the contact with those virus laden droplets. The virus laden droplets (nasal secretions, sputum, droplets) can also be transmitted by rubbing your nose/eyes or mouth by the contaminated hand. How can I protect myself? You can protect yourself by avoiding close contact with a person suffering from influenza so that you are protected from inhalation of the virus laden droplet. A person who is suffering from influenza also prevents the transmission of droplet by covering the mouth and nose during coughing and sneezing. The used tissues or clothes should not be disposed in the open air. You can protect yourself by accidental exposure to the virus by washing your hand frequently. Avoid rubbing or touching nose, eyes, and mouth. Infected person should also wash hands frequently to prevent accidental transmission of droplets. Are there any treatments for Influenza A-H1N1? Pandemic influenza A H1N1 can be treated by antiviral drugs. Consult your physician for treatment. Can I use antiviral-drug for prevention? Antiviral drugs can be used for prevention of Pandemic influenza only when you are at risk of acquiring infection. What is the danger of indiscriminate use of antiviral drugs? The danger of indiscriminate use of antiviral drugs is the development of influenza virus which became resistant to the available drug. The viruses can adapt to the drug and change their genes to produce new generation of virus which is resistant to the drug. So the drugs cannot effectively block the virus and you might suffer the illness in spite of taking treatment. What are the consequences of infection with Influenza A H1N1? You may develop headache, fever, body aches and pain, nausea, vomiting and diarrhoea within 3-7 days of exposure to the virus. You will recover well after 5-7 days. Some people even die from influenza. What are the problems? In some cases the illness is caused not only by influenza, but also by another infection such as bacterial and fungal infection. People with influenza infections are prone to

4 attract another bacterial infection. In that case, secondary bacterial infections may lead to severe pneumonia and death. Who are at risk of suffering serious illness? 1. Pregnant women 2. Adult and children younger than 24 years 3. People with chronic illness such as heart and lung diseases, diabetes. 4. People who are immunosuppressed due to cancer, chemotherapy or immunodeficiency diseases. Can I be protected by human Influenza vaccine? Human Influenza vaccine protects you from currently circulating human influenza A- H1N1, H3N2 and influenza B Pandemic Influenza A-H1N1 is a new virus and cannot provide full protection by currently available influenza vaccine. The vaccine for protection of pandemic influenza A-H1N1 is still developing. Why should I receive Influenza vaccine if it doesn t protect me from pandemic Influenza A -H1N1? You should receive influenza vaccine before winter. It will protect you not only from human influenza virus but also from the complications of influenza such as secondary bacterial pneumonia. Especially children and adults who are at risk of developing serious illness will benefit from human influenza vaccine. How can I help in the prevention of Pandemic Influenza? If you are sick, rest at home. If you are sicker after having flu like symptoms consult the clinic. A person who is suffering from flu or any chest infection should cover the nose and mouth when he or she goes out of their room to prevent droplet transmission. Wash your hands frequently. Some super-market and shops provide free hand sanitisers and tissue papers. You can use it to clean your hand if you are busy shopping. Cover your nose and mouth when sneezing or coughing. Preventing transmission of influenza virus by cough etiquette and frequent hand washing.

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