All About of Avian Influenza H5N1

Bird flu (avian influenza) is a disease caused by an influenza virus that primarily affects birds. In the 1990s, was a new strain of bird flu cause arising, notable for its ability to withstand severe illness and death, especially in domestic birds such as ducks, chickens, turkeys or. Therefore, this strain was called highly pathogenic (very strong) of the bird flu.

H5N1 avian influenza

Since the identification of highly pathogenic virus were infected birds in Asia, Europe, Middle East and Africa found. Strict control measures, including destruction of infected flocks and vaccination of healthy birds, have reduced the number of cases, but the virus continues to exist in poultry in parts of Asia and Africa. Avian influenza highly pathogenic strain is not the United States at that time.

The virus is spread from bird to bird by infected birds shed the virus in their saliva, nasal secretions, feces and spread. Healthy birds are infected when they come into contact with contaminated secretions or excretions from infected birds. The contact with contaminated surfaces such as cages could also happen the way the virus from bird to bird. Symptoms in birds range from a slight drop in egg production to the failure of major organs and death.

The first human case of highly pathogenic avian influenza of the disease was identified in 1997 and since then over 560 cases have been identified worldwide with more than 300 deaths. Human cases of HPAI have been largely confined to South Asia and Africa.However, mutations often occur in the virus, and it is possible that some mutations may be a contagious virus epidemic, which could be a regional or a global pandemic of bird flu cause people to create. Fortunately, the changes that have taken place so far, not made the virus more contagious, but remains a concern.

H5N1 cycle

Bird flu is caused by strains of influenza viruses, which evolved to be specifically adapted to penetrate into cells, bird flu. There are three types of influenza A, B and C. The virus that causes bird flu is an influenza A-type with eight RNA strands that make up its genome.Influenza viruses are by analysis of two proteins on the surface of the virus divided. The proteins are called hemagglutinin (H) and neuraminidase (N). There are many different types of proteins, hemagglutinin and neuraminidase. The current highly pathogenic avian influenza of the type 5 and neuraminidase type 1 hemagglutinin has So it is an "H5N1" flu virus.

There are many types of influenza virus, and most prefer to live in a limited number of animals. Sun affects the swine flu swine flu and bird flu strikes in birds. Human influenza is better adapted to humans. Some cases may in accidental hosts, such as when people who have extensive experience contact with sick birds, the bird flu. In addition to humans and birds, we know that pigs can, tigers, leopards, ferrets and domestic cats are often infected with bird flu virus.

Influenza viruses mutate easily and often. These mutations may occur spontaneously or may occur in a single virus, when two different influenza strains is close enough to get exchange genetic material. There are two types of mutations in influenza virus: antigenic variation, where large segments of DNA between the type of influenza virus are exchanged different, and modified antigenic changes, where small RNA sequences were. Antigens variations are usually responsible for the development of new varieties. For example, the causes of 2009 against the swine flu pandemic caused by a virus, the genetic material from swine flu, bird flu and human flu strains. New mutations can escape the virus to the body's immune system and makes it ineffective vaccines. In 2011, a virus mutated strain of highly pathogenic avian influenza in this manner so that existing vaccines ineffective against bird flu used against the new strain. Sometimes a flu virus is mutated in a way which makes it can infect a new species.

A severe flu pandemic occurs when a relatively new strain of influenza virus produced is very contagious to humans. The most deadly pandemic in modern history was the 1918 flu, also known as Spanish flu known (even if it did not originate in Spain). The 1918 virus spread quickly and killed tens of millions of people worldwide.Mortality was particularly high in healthy young adults. Although the virus was in 1918 a human influenza virus, it took a number of genes that probably came from a strain of bird flu. One reason why health authorities to monitor carefully and try to human contact with birds, which is to limit thrive against the bird flu, the chances of a new species, which prefer to avoid resulting in the development of human tissues.

Humans can catch bird flu through contact with infected birds (chickens, for example) or their infected feces or surfaces with faeces. Risk factors include caring for sick birds, killing sick birds, and preparation of sick birds for consumption. Despite the large number of people who have contact with poultry every day in the world, human cases of avian flu are rare. This underlines how difficult it infect the bird flu virus human cells, but mutations such as antigenic changes can reduce these difficulties.

Although direct contact with diseased poultry is the highest risk of indirect exposure to bird droppings is also a risk. Is contact with unwashed eggs from sick birds or water contaminated with feces from poultry is a potential risk of the disease.

Human transmission has occurred in individual cases. In order for the care of a person is infected with bird flu, a risk factor for the disease. There is a theoretical risk in laboratory workers to handle the bird flu virus. An alleged incident in 2009 occurred when a company accidentally sent live avian flu virus samples to research laboratories, which were then used to vaccinate ferrets. The contaminated vaccine made yet in the human cases.

Symptoms appear about two to eight days after exposure, on average. Infected people experience typical flu symptoms like fever, cough, sore throat and muscle aches. Some people also have nausea, vomiting, diarrhea and eye infections. This can lead to pneumonia and even respiratory arrest progress. The bird flu leads to a very aggressive form of pneumonia (respiratory distress syndrome or ARDS), which is often fatal.

Routine tests for human influenza A is positive in patients with bird flu, but are not specific to the bird flu virus. To make an accurate diagnosis of bird flu, specialized testing is needed. In the U.S., the local health department and the Centers for Disease Control and Prevention provide access to specialized tests. The virus can be detected in the sputum of several methods, including the culture or polymerase chain reaction (PCR). Culture should be in laboratories, the appropriate certification of biological safety are done. The PCR, the nucleic acid of influenza virus A PCR must be identified in specialized reference laboratories for avian influenza strains available.

During and after infection with bird flu, the body makes antibodies against the virus. Blood tests can detect these antibodies, but this requires a trial to the beginning and again later in a few weeks.Therefore, the results are not available until the patient recovered or died.

Due to the limited number of human cases, it was not possible to conduct rigorous studies on the treatment of bird flu. The current recommendation of the World Health Organization is to use an antiviral drug called oseltamivir (Tamiflu). In September 2011, the CDC has said: "Two other antiviral medications oseltamivir and zanamivir, would probably work to be caused by H5N1 influenza, but need further studies carried out to demonstrate their effectiveness."

The prognosis in cases of human bird flu remains low. Many cases occur in people who are poor live in rural areas in underdeveloped countries, and no new access to intensive care or antiviral therapy.About 60% of persons diagnosed with avian flu ultimately die from the disease.

Bird flu can be achieved by avoiding contact with sick poultry from countries affected by the virus to prevent its. In 2011, Egypt has reported the most cases to date. Prevention also includes safety measures such as the destruction of poultry flocks, where sick birds were identified, and the vaccination of healthy cattle. Combined with import bans, has effectively limited the spread of this culling bird flu, but of course has negative effects on the poultry and egg industry.Unlike some researchers suggest that SARS was from the world or the Ebola virus, which has a close spatial extent eliminated, there goes the bird flu in important regions of the world and can spread widely by migrating birds.

Properly handling and cooking poultry and eggs can kill viruses like the bird flu virus. Hands should be washed before and after handling poultry and eggs, and surfaces that come into contact with food must be thoroughly cleaned with hot soapy water. Cooked poultry must be an internal temperature of at least 165 F.

Respirators and others should be used when caring for patients with bird flu. If a person is in close contact with an infected patient, the person can immediately be offered to oseltamivir in an attempt to prevent infection.

In  2007 the FDA approved the first vaccine in the United States for the people against the virus HPAI. The vaccine is made from inactivated virus and does not contain any live virus. It has been shown to stimulate the immune system to produce antibodies against the virus of bird flu, which could probably do to protect people against bird flu. The vaccine was purchased by the federal government for inclusion in the Strategic National Stockpile CDC. It is not for the general public, partly because the U.S. does not currently have a problem with the highly pathogenic bird flu. Vaccine side effects include a sore arm, fatigue, muscle pain and temporary.The vaccine was tested in many patients, however, and it can be other side effects is not yet covered. The current vaccine is effective against the strain that causes large outbreaks of bird flu, but it can not be found as effective against a new mutant strain in 2011.

Research on vaccines against the influenza virus is not yet complete, and new development as a vaccine antigen that is addressed often and relatively constant over the flu virus, a vaccine that protects against most leading, if not all of the influenza virus. If this research is successful, the potential influenza outbreaks, including avian influenza, can be reduced or avoided in the future.