H5N1, avian (bird) influenza - be aware and prepare
Cumulative Number of Confirmed Human Cases of Avian Influenza A/(H5N1) Reported to WHO (World Health Organization): since 2003
Azerbaijan
cases = 8
deaths = 5
Bangladesh
cases = 1
deaths = 0
Cambodia
cases = 8
deaths = 7
China
cases = 30
deaths = 20
Djibouti
cases = 1
deaths = 0
Egypt
cases = 50
deaths = 22
Indonesia
cases = 139
deaths = 113
Iraq
cases = 3
deaths = 2
Laos
cases = 2
deaths = 2
Myanmar
cases = 1
deaths = 0
Nigeria
cases = 1
deaths = 1
Pakistan
cases = 3
deaths = 1
Thailand
cases = 25
deaths = 17
Turkey
cases = 12
deaths = 4
Viet Nam
cases = 106
deaths = 52
Total
cases = 390
deaths = 246
Total number of cases includes number of deaths.
WHO reports only laboratory-confirmed cases. (12 December, 2008)
Over 60 countries have reported outbreaks of the H5N1 strain of avian influenza since 2003.
More than 300 million birds have died or been destroyed in an effort to prevent further spread of the virus, according to the U.N. Food and Agriculture Organization.
That level of disease among domestic flocks has been characterized as an animal pandemic, and a costly one. $2.5 billion has gone into the international effort to control and eradicate the disease.
Avian Flu: Frequently Asked Questions
1. What is avian influenza?
Avian influenza (such as H5N1, H9N2) is a type of influenza A. It was known previously to infect birds only, but 18 human cases caused by the H5N1 strain were documented in Hong Kong in 1997 and another two were documented in 2003.
2. What is the difference between viruses causing human influenza and those causing avian influenza?
Human influenza and avian influenza are both caused by influenza viruses. In Hong Kong, human influenza is commonly caused by influenza A (H3N2), influenza A (H1N1) and influenza B viruses, while avian influenza is commonly caused by influenza A (H5N1) and influenza A (H9N2) viruses.
3. What are the symptoms of avian influenza?
The initial symptoms of avian influenza are similar to those of other influenza viruses, including fever, headache, muscle pain, runny nose, cough and sore throat. However, it is more likely to result in high fever, chest infection, respiratory failure, multi-organ failure, and death.
4. How can I tell the difference between having avian influenza and SARS?
You cannot differentiate between avian influenza and SARS by symptoms alone. Confirmation of diagnosis will depend on laboratory tests on clinical samples from the patient.
Transmission
5. How is avian influenza transmitted?
Avian influenza is transmitted from infected live birds to humans. Human-to-human transmission is inefficient. Outbreaks of avian influenza in poultry have recently been reported in some Asian and European countries, and some cases of human infection have been reported. Hong Kong has an effective surveillance system for influenza in birds and humans. The Department of Health has been closely monitoring the situation and has adopted appropriate preventive measures to guard against the disease.
6. Why bother if the H5N1 virus does not usually infect humans?
Avian influenza is transmitted from infected live birds to humans. Although human-to-human transmission is inefficient, all influenza viruses have the ability to change genetically, and scientists are concerned that the H5N1 virus could one day be able to spread easily from one person to another. Because the virus does not commonly infect humans, there is little or no immune protection against it in the human population. If the H5N1 virus could spread easily from person to person, an influenza pandemic could occur. No one can predict when a pandemic might strike. However, experts from around the world are watching the H5N1 situation very closely and are preparing for the possibility that the virus may begin to spread more easily and widely from person to person.
7. Who is susceptible to contracting the disease?
People in close contact with poultry are more susceptible to contracting avian flu. The elderly, children and people with chronic illness have a higher risk of developing complications such as bronchitis and pneumonia.
Posted in: Bird flu| Tags: Bird fluChicken tested H5N1 positive in HK
Do you remember this?
Hong Kong health authorities closed down a poultry market here Saturday after excrement samples collected from hencoops at the marketplace were confirmed infected with the deadly strain of H5N1 avian influenza virus.
Dr. York Chow, Secretary for Food and Health, announced at a press conference here Saturday afternoon that the Po On Road Market in Kowloon an infected area of the H5N1 virus and ordered the immediate suspension of trading in the market.
Chow said after days of laboratory testings, five of the 20 excrement samples collected from three poultry stores on June 3 were confirmed H5N1 positive and an order was issued immediately to cull about 2,700 chickens in the market.
"We are still investigating on the source of the H5N1 virus infections," he said, adding other 64 poultry markets had reported no H5N1 cases.
Chow said there has been no report of human case of H5N1 infections but the department had decided to raise the response level from "vigilance" to "serious" in the city.
In response to the latest H5N1 virus find, Chow said, the Food and Health Department had suspended immediately the live poultry imports from the Chinese mainland and trading from local chicken farms will be suspended immediately
He said such suspension will last for as long as 21 days if necessary.
Chow said the Hong Kong Special Administrative Region government had noticed the Ministry of Agriculture and the General Administration of Quality Supervision, Inspection and Quarantine on the latest development of bird flu in Hong Kong.
Chow said there had been no unusual incidents reported in the registered chicken farm in the Chinese mainland and none abnormal death of poultry had been reported by store owners during the past days.
Thomas Tsang, Controller of the Center for Health Protection, said the center would conduct health checkups and prescribe anti- virus medicine for those people in close contact with live poultry.
Tsang also called on doctors in the city to quickly report suspected cases of H5N1 infection to the center once they diagnose those patients with a fever.
The Agriculture, Fisheries and Conservation Department said they would strengthen the testing of live poultry on the bird flu virus and disinfecting of poultry whole sale markets.
Posted in: Bird flu| Tags: Bird flu H5N1Asian H5N1 Influenza A Viruses In Domestic Ducks
Scientists are looking at a novel strategy to prevent the spread of pandemic avian influenza. They have developed a vaccine that protects ducks, a known natural reservoir for the virus.
Waterfowl are considered to be the natural reservoir of influenza A viruses due to the isolation of all subtypes from these hosts. Current research indicates that influenza A viruses are continuously evolving within their natural environment and can be transmitted to a variety of animals, including humans. H5N1 avian influenza A viruses are now endemic in domestic poultry in many Asian countries and ducks are believed to be the primary source of infection. Reducing the spread of H5N1 in ducks could play a key role in minimizing the risk of a pandemic outbreak.
In the study researchers first identified dominant pathogenic strains of H5N1 influenza A viruses circulating in Asian poultry and found that four caused symptomatic illness in domestic ducks, but not all were lethal. In addition the researchers reversed the genetics of the viruses in domestic ducks to develop three different inactivated oil emulsion whole-virus H5 influenza vaccines. Following one round of inoculation with the vaccines ducks were completely protected when challenged with a lethal dose of the H5N1 virus.
"The vaccines provided complete protection against the lethal challenge of the homologous and heterologous H5N1 avian influenza A virus with no evidence of morbidity, mortality, or shedding of the challenge virus," say the researchers. "The complete protection offered by these vaccines will be useful for reducing the shedding of H5N1 avian influenza A viruses among vaccinated agricultural avian populations."
The concern is greatest in rural areas of affected countries, where traditional free-ranging ducks, chickens and wildlife mingle, frequently sharing the same source of water, according to a joint statement by the UN Food and Agriculture Organization (FAO), the World Health Organization (WHO) and the Office International des Epizooties (OIE).
Findings pointing to an altered role for domestic ducks join other recent evidence that the H5N1 virus circulating in parts of Asia has increased its virulence in chickens and mice (a laboratory model for mammals), and has expanded its host range to include mammals, such as certain members of the felidae family (e.g. cats and tigers), not previously considered susceptible to infection.
Posted in: Bird flu| Tags: H5N1 Bird flu