Wear Respirator in Place of Face Masks for Bird Flu Virus Protection
While the bird flu can be serious, unless you have household chickens and live in a country where there's an outbreak now, the bird flu probably is not an immediate health threat for you or your family. Experts believe only 160 people have contracted the disease since it was identified as a threat 8 years ago.The pandemic flu virus in humans is most likely to come from a change in the avian flu virus H5N1.
Human influenza is transmitted by inhalation of infectious droplets and droplet nuclei, by direct contact, and perhaps, by indirect (fomite) contact, with self-inoculation onto the upper respiratory tract or conjunctival mucosa. The relative efficiency of the different routes of transmission has not been defined. For human influenza A (H5N1) infections, evidence is consistent with bird-to-human, possibly environment-to-human, and limited, nonsustained human-to-human transmission to date.
Experts are concerned that this flu could mutate (undergo a genetic change) into a new form that can spread from person to person. Right now there's no vaccine for the bird flu, so they're worried that if it does mutate, it will be difficult to stop and will cause a pandemic, which is a global outbreak.
Outbreaks are usually alarming events that can elicit great anxiety in the general public. This anxiety can endure even when new knowledge about the outbreak is reassuring. The extreme behaviours that can result are well documented and range from the wearing of masks and avoidance of travel, through fear of hospitals and stigmatization of patients and minority groups, to riots, loss of confidence in governments, and significant drops in consumer consumption. Outbreaks thus have the potential to cause social disruption and economic losses well beyond health care costs and out of proportion to the true severity of the risk.
Viruses often change (mutate). They may then spread more easily among animals and humans. They can also become more deadly. The strain of influenza that is now common in birds in Asia could change into a flu that spreads more easily to humans. National and world health organizations worry that a mutated bird flu virus could cause a world-wide epidemic (pandemic). Many people have at least some immunity to human viruses, which means their body can more easily fight the virus. A pandemic happens when there are worldwide epidemics of flu caused by a new flu virus to which people have little or no immunity.
In 1997, exposure to live poultry within a week before the onset of illness was associated with disease in humans, whereas there was no significant risk related to eating or preparing poultry products or exposure to persons with influenza A (H5N1) disease.Exposure to ill poultry and butchering of birds were associated with seropositivity for influenza A (H5N1) . Recently, most patients have had a history of direct contact with poultry , although not those who were involved in mass culling of poultry.
Plucking and preparing of diseased birds; handling fighting cocks; playing with poultry, particularly asymptomatic infected ducks; and consumption of duck's blood or possibly undercooked poultry have all been implicated. Transmission to felids has been observed by feeding raw infected chickens to tigers and leopards in zoos in Thailand and to domestic cats under experimental conditions. Transmission between felids has been found under such conditions. Some infections may be initiated by pharyngeal or gastrointestinal inoculation of virus.
The best protection of all is an effective vaccine. The world will need to produce vastly increased volumes of vaccine when the time comes. This is a huge challenge. Currently there is no vaccine that we know will be effective. Nor is there sufficient manufacturing capacity at present. There are no immediate and easy solutions to these issues.
Face masks may do little to prevent infection during an influenza pandemic, but wearing them might help comfort people in crowds, the U.S. Centers for Disease Control and Prevention said .
And people who must care for someone else who is sick during a pandemic should wear a respirator -- a specially designed, form-fitting mask, the CDC said.
It admitted that no one has done the research to show what good, if any, a surgical-style mask would do in stopping the spread of a virus.
Experts say a flu pandemic is inevitable. No one can say when it will come, or what strain of virus, but there were three flu pandemics in the last century.
The chief suspect is the H5N1 avian flu virus infecting flocks of birds across Asia, parts of Europe and Africa. It rarely infects people but has killed at least 172 of the 291 people whose infection was confirmed by the World Health Organization.
If it develops the ability to pass easily from one person to another, it would infect tens of millions of people and could kill millions, WHO says. A good vaccine would take months to manufacture.
Many experts have been asking questions about whether masks might help people protect themselves and might be worth stockpiling now.
The CDC's answer? Maybe.
"We also know that many people may choose to use masks for an extra margin of protection even if there is no proof of their effectiveness," CDC director Dr. Julie Gerberding told reporters.
"If people are not able to avoid crowded places, large gatherings or are caring for people who are ill, using a face mask or a respirator correctly and consistently could help protect people and reduce the spread of pandemic influenza."
Other measures already recommended by the CDC and WHO include hand washing, staying away from other people and discouraging crowds.
Some experts have argued that wearing a face mask might give people a false sense of security.
Face masks might be useful in the following instances, the CDC said:
-- If people have the flu and think they might have close contact with other people -- within about 6 feet.
-- If they live with someone who has the flu symptoms or will be spending time in a crowded public place and thus may be in close contact with infected people.
-- If people must be in a crowd.
-- People should use a respirator mask if they must be in close contract with someone who is ill.
"Face masks are not designed to protect people from breathing in very small particles, such as viruses," said Dr. Michael Bell, an infection control expert at CDC.
"Rather, face masks help stop potentially infectious droplets from being spread by the person wearing them. They also keep splashes or sprays from coughs and sneezes from reaching the mouth and nose of the person wearing the face mask."
Currently the H5N1 avian influenza virus is the most likely candidate virus for the next influenza pandemic. There is only one condition missing - a virus that is rapidly transmitted from person to person.Since 1997, when the first human cases of bird flu appeared, hundreds of millions of sick or exposed birds — primarily chickens — have been destroyed. In many cases, affected farms were also quarantined. The WHO considers this approach the first-line defense against avian viruses.
Some argued against telling the public anything that was not told first to stakeholders. Should a public health decision that all aircraft should be equipped with respiratory masks be made public before airline executives have been informed? Others argued that the public itself should be viewed as a stakeholder; past problems had arisen because legitimate public concerns were not considered in the decision-making process.
Highly infective avian flu viruses, such as H5N1, have been shown to survive in the environment for long periods of time, and infection may be spread simply by touching contaminated surfaces. Birds who recover from the flu can continue to shed the virus in their feces and saliva for as long as 10 days.Healthcare workers and household contacts of patients with avian influenza may also be at an increased risk of the bird flu.
Cook chicken until the juices run clear, and it reaches a minimum internal temperature of 165 F.Carefully wash cutting boards, utensils and all surfaces that have come into contact with raw poultry in hot, soapy water. Wash your hands thoroughly before and after handling poultry and dry them with a disposable towel.Because eggshells are often contaminated with bird droppings, avoid mayonnaise, hollandaise sauce, ice cream, and any other foods containing raw or undercooked eggs.Keep a careful eye on young children, who are likely to put their hands in their mouths and who may not wash thoroughly.
Infants with the flu may simply seem sick all of a sudden or "just don't look right." The flu that people get is not the same strain of virus as the avian flu.Spread by virus-infected droplets that are coughed or sneezed into the air, the flu is contagious. People infected with the flu are contagious from a day before they feel sick until their symptoms have resolved (usually about 1 week for adults, but up to 2 weeks for kids).
Never pick up used tissues.Never share cups and eating utensils until you're better.Stay home from work or school when you're sick with the flu. Cover your mouth and nose with a tissue when you cough or sneeze.
A person can spread the flu starting one day before they feel sick. Adults can continue to pass the flu virus to others for another three-to-seven days after symptoms start.Symptoms start one-to-four days after the virus enters the body. Some persons can be infected with the flu virus but have no symptoms. During this time, those persons can still spread the virus to others.
There was no advance warning for the three pandemics of the previous century. We have to keep a look out for a change in the pattern of human flu cases. We must detect human to human transmission at the earliest stage possible. Each country - each community - needs public health early warning systems that work.. This means improving surveillance for disease in animals and humans, field investigations, diagnostic support, and incentives for people to report.
The five keys to safer food :
- Keep clean
- Separate raw and cooked
- Cook thoroughly
- Keep food at safe temperatures
- Use safe water and raw materials