Avian Influenza (Bird Flu)

Abstract

THERE IS NO PANDEMIC AVIAN INFLUENZA in the world today but we must be prepared. We do not know when or where a pandemic may begin or how severe it will be. What is a pandemic? A pandemic is a global disease outbreak. A pandemic flu happens when a new flu virus appears in humans causing serious illness, large numbers of deaths and spreads simultaneously worldwide. Pandemics of flu are caused by new viruses. Humans have little or no protection against a new pandemic virus because they have not been infected with a similar virus before.

Ongoing worldwide efforts to produce a vaccine for humans is in process by manufactures and clinical trials are being preformed in several countries.

History of three pandemic influenza viruses in the 20th century:

• 1918-19-"Spanish Flu" (A(HlNl) known to have caused the highest number of influenza deaths. More than 500,000 people died in the United States and approximately more than 50 million may have died worldwide.

• 1957-58-"Asian Flu" (A(H2N2) approximately caused 70,000 deaths in the United States. It was identified in China in February 1957; it then spread to the United States by June 1957.

• 1968-69-"HongKongFlu" (A(H3N2) caused approximately 34,000 deaths in the United States. The virus was identified in China in early 1968 and it spread to the United States in the same year. This type of virus (H3N2) still circulates today.

The viruses from 1957-58 and 1968- 69 were both caused by viruses containing a combination of human influenza virus and an avian influenza virus. The 1918-19 influenza pandemic virus appears to have had an avian origin.

There has not been a confirmed case of Avian Influenza (HSNl) in humans in the United States and the American government monitors every aspect of the disease to keep the public informed since it developed in 1997. Since it developed in 1997 to 2006, there were several outbreaks of low pathogenic avian influenza A viruses (HS and H7 subtype) and one outbreak of highly pathogenic avian influenza A (HSN2) in poultry in the United States. In 2003 New York reported that a person was infected with the H7N2 avian influenza A virus, the patient recovered and was sent home. Maryland, Delaware and New Jersey reported outbreaks of the (H7and N2) to poultry without human transmission in 2004. In the same year, Texas reported an outbreak of HSN2 to poultry without human transmission. In 2006 Michigan, Maryland and Pennsylvania reported LPLI HSNl in wild swans and wild ducks.

The World Health Organization (WHO) has reported many cases of humans infected with the avian influenza A virus (HSNl). Vietnam and Indonesia have the highest number of human cases reported. Other countries such as those in Eastern Europe, Africa and Asia have also reported human cases. Mortality is reported in almost 60% and the majority are children and adults less than 40 years old. The highest mortality occurred in cases ranging from 10 to 19 years old. Education is critical to prepare for a pandemic. We need to understand what a pandemic is as well as what needs to be done at all levels in order to be prepared.

When a pandemic influenza virus emerges, its global spread is considered inevitable. Countries may delay arrival of the virus through measures of restricting travel and closing borders but it will be very difficult to stop it. This is why it is very important to be armed with information because the public can play a big role in helping the government control the disease.

**Cumulative Number of Confirmed Human Cases of Avian Influenza A/ (HSNI) Reported to World Health Organization (WHO). 30 April 2008

**Total number of cases includes number of deaths. WHO reports only laboratory-confirmed cases. All dates refer to onset of illness.

**For a full detailed timeline of major events for each country reporting avian influenza in animals and humans go to: www. who. int/ cs r I disease/ avian influenza/ai timeline/en/index.html

Flu Terms Defined

(from www.avianflu.gov) Seasonal (or common) flu: A respiratory illness that can be transmitted person to person. Most people have some immunity and a vaccine is available.

Avian Influenza (or bird flu): Caused by influenza viruses that occur naturally among wild birds. The HSNI variant is deadly to domestic fowl and can be transmitted from birds to humans. There is no human immunity and no vaccine is available worldwide yet, but there is global ongoing research to develop a vaccine. Several countries are trying "test" vaccines to treat the HSNI virus. These clinical trials will help improve the research to develop a vaccine for the future to be used worldwide.

Pandemic flu: A virulent human flu that causes a global outbreak or pandemic of serious illness and deaths. Because there is little natural immunity, the disease can spread easily from person to person. Currently, there is no pandemic flu.

An informed and responsive public is essential to minimizing the health effects. Today, people do not have all the correct information about the avian flu. Ignorance can only hurt us, this is why it is very important to arm yourself with information as well as be prepared in case the pandemic reaches our country.