Maintaining Your Health on Mackinac
What Is Currently Known About Avian (Bird) Flu?
By Yvan Silva, M.D.

Birds can become infected with flu virus strains that are specific to birds and not humans. The now notorious H5N1 bird flu strain was first identified in Asia in 1997. This virus, like other avian viruses, spreads among birds, causing death on a huge scale. Millions of domestic birds have been culled in affected countries and vaccination of birds has been employed in large numbers in order to prevent and contain the spread among the birds. Of major concern now is the fact that the bird flu virus has "passed" into humans.

Bird flu is spread by direct and continuing contact with diseased birds by uncooked flesh, blood, droppings, and feathers. At this time, a few cases of human infections have been confirmed; these were within similar households with domestic birds with the disease or in individuals with close commercial contact. Tourists have not been reported to have contracted bird flu. There are no travel advisories by U.S. health agencies against visiting countries because of avian flu. For travelers, it is advisable to monitor releases on Web sites of the U.S. government and the World Health Organization. Current recommendations are against travel to areas where outbreaks have occurred; avoidance of poultry farms, markets with live birds, and areas heavily contaminated with bird droppings.

Avian flu is not transmissible through cooked meat and there is no reason to avoid eating chicken. Health experts have warned against eating raw or partially cooked poultry products. European authorities are recommending that only cooked eggs be consumed. Eggshells are known to carry the virus and proper hand washing and disposal are recommended. Several restaurants in Europe, also responding to a decrease in demand, have stopped serving some poultry products including chicken, duck, and goose. Salads made with raw eggs are also off the menu.

When travel to an affected area is necessary, there are several precautions that are helpful. As with other infectious diseases, proper hygiene is essential. Frequent hand washing with soap and, when soap is not available, appropriate sanitizer products should be used.

There is no human vaccination available for protection against avian flu. However, protective vaccination, as usual, is recommended against regular flu. As with other international travel planning, up to date prophylaxis recommended for the areas to be visited should be undertaken; malaria is an example. There are two antiviral drugs that are effective against flu and against the bird flu, as well. Tamiflu and Relenza for prophylaxis are not routinely recommended for travelers. People with occupational risks or high risk contacts with infected birds might consider using them. Physician prescriptions are required. If there is contact with live poultry and fear that exposure to bird flu might have occurred, it is important to follow these guidelines: monitor yourself closely for 10 days for signs of fever, chills, cough, or difficulty breathing. If these symptoms are significant, immediate medical consultation is advisable along with information regarding the areas where contact may have occurred and the nature of the contact.

Recent experience with the SARS epidemic has provided important information about the potential for a pandemic, and the difference between the SARS and other viruses. SARS affected 29 countries; 8,437 people were diagnosed with the infection and 813 died. The epidemic lasted six months. SARS had a longer incubation period than other viruses and SARS was most contagious when infected individuals were most symptomatic, that is they were very ill. Other flu strains have a shorter incubation period. Affected individuals may have minor symptoms or none at all, and widespread containment is therefore a bigger challenge.

Health authorities all over the world are now poised with concerns about a potential global pandemic. Antiviral drugs are being stockpiled, and planning for prevention of spread by quarantine and other measures is underway. Prompt reporting of cases, tracking of migratory birds dying from infection, testing of individuals suspected of having the bird flu, and heightened overall surveillance are evident in media and health agencies reporting.

In the event of a pandemic, the U.S. government would probably consider the screening of all passengers arriving from high risk destinations for flu-like symptoms. If it does occur in the

U.S., it is probable that sick individuals would be quarantined. U.S. quarantine stations currently in operation are staffed by physicians, public health officials, and support staff. If needed, more stations will be opened. It is possible that cancellation of large public events will become necessary, guidelines for home and workplace will be issued, and health care facilities will be expanded to accommodate larger numbers of patients. When it becomes a public health threat, quarantine regulations are enforceable by law.

For now, this much is known. Human cases of avian flu are being reported sporadically in various countries. Passage of the H5N1 virus from infected birds to human beings has occurred. There is no vaccine available for humans against this threat. The risk for infection is positive for close contact with infected birds. Avian flu is not transmitted via properly cooked meat. Travel to high risk destinations should only be undertaken, as with all international potential risks, after attention to appropriate national and international travel advisories.

It is not known when and where an outbreak may occur. It is not known if a national or global pandemic will ensue. Should these threats ensue, intensive local and regional surveillance, enforced quarantine, and other preventive measures can be anticipated.

Dr. Silva is a professor of surgery at Wayne State University and a resident of Woodbluff on Mackinac Island.