Food Protection Connection: A Closer Look at Bird Flu

(reprinted from Dietary Manager, April 2004)

The newest global health concern poses confusing questions for anyone involved in food protection. Much like mad cow disease (BSE), an infectious illness called bird flu has driven health officials to destroy large groups of animals. In this case, the animals are chickens rather than cows. Twelve thousand chickens in Delaware were destroyed in February 2004, following the discovery of bird flu among them.

Furthermore, bird flu in US poultry flocks has led to bans on imports from the US: South Korea banned US poultry imports in February 2004, and the European Union banned import of live chickens and eggs (for hatching) following the discovery of bird flu in Texas, also in February. These news stories may remind us of cattle import bans that have followed emergence of mad cow disease in the US (see Food Protection Connection, March 2004).

Despite the superficial parallels between mad cow and bird flu, it’s important to note what is different between the two situations. Mad cow disease is a foodborne illness (FBI). It is defined as such because technically, it can travel through food sources to cause infection. Bird flu, however, is not a foodborne illness, even though it is cropping up among chickens.

Bird Flu Beginnings

If it’s not a foodborne illness, then what is bird flu? Much as the name implies, bird flu is a virus-related illness that infects birds. You may also hear it called influenza or avian flu virus. The virus makes birds ill, much as the flu-viruses that circulate among humans make us ill. Health officials say the bird flu virus is common in the wild, but wild birds are largely resistant to it. The problem arises as the virus reaches domesticated poultry, who do not share this resistance. Entire flocks have become infected, with rampant deaths.

There is a human connection. Ordinarily, the avian flu virus would not circulate among humans. But since it has reached poultry farms, it has also affected people who have close contact with live, infected chickens. Humans, like farm chickens and turkeys, have no natural resistance to the virus. In 1997, the chicken-human connection was discovered in Hong Kong, after 18 people were infected, and six died. Within just days, officials destroyed the entire domestic poultry population of Hong Kong to prevent the spread of the virus. Since then, humans have succumbed to the virus in other parts of Asia and the Netherlands, too. Most likely, the virus can also spread from one person to another, although scientists are not entirely sure. Symptoms include eye infections, cough, pneumonia, fever, sore throat, and muscle aches.

Pandemic Potential

Today, scientists worry that the virus has the potential to cause an influenza pandemic. Explains the CDC, “An influenza pandemic is a global outbreak of influenza (flu) that occurs when a new influenza virus emerges, spreads, and causes disease worldwide. Past influenza pandemics have led to high levels of illness, death, social disruption, and economic loss.” In the 20th century, says the CDC, we have seen three pandemics: Spanish Flu in 1918-19, which killed half a million people in the US; Asian Flu in 1957-58; and Hong Kong Flu in 1968-69. The World Health Organization warns that bird flu could be more dangerous than the highly publicized SARS virus.

In all, experts can name 15 strains of avian flu virus. Some are more vicious than others. The strain found in Texas, called H5N2, is mild and probably cannot pass to humans, say health officials. Another strain, H5N1, however, does. Cats and other animals can contract the virus as well. As we have seen with many viruses, the ability of microorganisms to mutate—or change genetically—is an ongoing concern. As viruses change, their ability to travel among living creatures and cause illness can change, too. Currently, though, experts emphasize that there is no bird flu virus in our retail food supply, and there is no evidence that the virus can transmit itself through food.

Questions & Answers

In summary, the mention of poultry and illness in the same breath commands attention from every foodservice professional who is committed to food protection. We offer the following questions and answers as a guide to setting policy and explaining it to others:

Q: Bird flu affects poultry, so is it a foodborne illness?
A: No, because it is not transmitted through food.

Q: With other countries banning poultry imports from the US, can we safely serve poultry and eggs to our clients?
A: Yes, because the bans target live birds and eggs, and are generally intended to limit bird-to-bird transmission. Poultry served as food does not contain the virus, even in its raw, uncooked state. The virus has never been found in retail chicken.

Q: But people have become ill with avian bird flu. Are we really safe?
A: Humans who have contracted the virus had close contact with live birds, such as poultry farm workers. They may contract it by handling bird droppings. Consider the farm-to-fork approach to food safety: The virus strikes on the farm, but not at the fork.

Q: If a foodservice worker has avian flu virus, should he or she be allowed to work?
A: No. This is not due to a food-related risk. Instead, the concern would be spread of the flu from person to person.

Q: So is the bird flu scare just a lot of media hype?
A: No, the threat is real. If the avian flu virus establishes itself among people, it could spread rapidly and cause a worldwide pandemic.

Q: Are these the final answers?
A: Yes, for now. But no, not forever. Scientists are monitoring strains of the avian flu virus closely to identify potential changes that may occur through genetic mutation and to pinpoint transmission of the virus to humans. In short, the food connection for bird flu is a nonissue. Thank goodness, here is one pathogen we can cross off our list of food protection worries.

By Sue Grossbauer