2006-03-14-Scientists in NE quietly test travelers for bird fluUnderstanding Avian Influenza
2006-03-14-Scientists in NE quietly test travelers for bird flu
Ten times since last summer, Massachusetts state scientists in white biological safety suits have tested specimens from patients whose symptoms and travels suggested that they might have been infected with avian influenza.
All the tests performed at the Jamaica Plain lab came back negative, but the decision to quietly start screening for bird flu signals deepened concerns.
Health officials said the work reflects concern about a possible global pandemic. Fears about the virus resonate even in the deepest corners of Maine, where two weeks ago, a doctor called the health department, beseeching lab workers to review a patient's sample.
''So we did it," said Kenneth Pote, senior scientist at Maine's state lab in Augusta. ''It was just one of these things where the physician freaked more than anything else."
Connecticut is the only other New England state so far that has examined specimens for the H5N1 virus that causes bird flu, with two tests in recent months. As in Massachusetts, the tests in Connecticut and Maine showed no evidence of the lethal virus.
Since 2003, avian influenza has sickened 177 people and has killed 98, according to the World Health Organization. Until this year, all the human cases were reported to have been in Asia.
But the virus has spread westward, in both birds and people. Human cases have been reported in Iraq and Turkey. Now there is concern that migrating birds could carry the virus to the United States this spring.
The New England health departments decided to test throat and nasal specimens because they met criteria established by disease specialists for potential bird flu cases.
Those include medical symptoms such as severe respiratory conditions and a fever. People tested had traveled in areas of the world where avian flu is common among birds. Typically, before a test is warranted, there has to be evidence that the patient had contact with birds.
''In the case of those we tested, they had theoretical contact: They stayed in a hotel, and there were chickens somewhere near, and when they got back from traveling, they were ill," said Dr. Alfred DeMaria, director of communicable disease control for the Massachusetts Department of Public Health.
''You don't want to miss a case," he said.
Disease trackers have found no evidence that the virus can spread efficiently from one human to another. Instead, people who have contracted the infection have typically had close and sustained contact with diseased fowl.
Infectious disease specialists are divided over whether avian influenza will gain the potential to cause a global wave of illness among humans.
Some scientists argue that the virus is only a few genetic steps away from being able to do that, while others remain dubious.
Still, there has been no dispute over the need to ensure that government labs are prepared to rapidly screen throat and nasal specimens for the presence of bird flu.
''You're talking about something that's never been seen here before," said Rosemary Humes, an official with the Association of Public Health Laboratories in Maryland. ''And the public health impact of a positive result is going to be massive."
Five weeks ago, the US Centers for Disease Control and Prevention announced that the organization had received clearance from federal drug regulators to begin shipping sophisticated chemicals for avian flu testing. ''Before, we were giving people the recipe so they could create the test in their own lab," Humes said.
Now, the CDC is shipping the improved testing kit to about 140 state and local government labs in the United States, said Richard B. Kellogg, who leads the CDC's effort to better coordinate the labs' response to situations considered to be health emergencies.
''You need to have a standardized test, because time is working against you," Kellogg said. ''And you need time on your side."
Scientists at state labs in New England, which had been using the less-advanced methods, said last week that they had all received the state-of-the-art testing material from the CDC.
The largest lab in the region -- and one of the most respected in the nation -- sits on a hill near the Forest Hills T station in Jamaica Plain.
There, scientists in the State Laboratory Institute are on call 24 hours a day for potential avian flu specimens and other infectious agents. The most recent suspicious sample arrived Feb. 27.
When a patient's infection raises concerns, a doctor typically uses a swab to derive a fluid sample from the throat or the nose.
Then, it has to be kept at about 39 degrees Fahrenheit before it is transported from the doctor's office to the state lab.
''The virus is very fragile once you take it outside of the body, so it's kept cold," said Sandra C. Smole, director of molecular diagnostics. ''We like to have it within 24 hours of collection."
Once a potential avian flu sample arrives at the state facility, a web of labs inside the building is activated to carry out various steps in the testing process.
In one step, detergent is used to inactivate the viral sample, rendering it harmless. In another step, scientists extract genetic material from the virus for testing.
''If you can find the needle in the haystack, you can amplify what you've found," Kellogg said. ''And then you can put it through an instrument, and it will tell you, 'Hey, now we've found it.' ''
That instrument performs something called a PCR analysis.
And if the testing, which takes four to six hours, is positive?
''That's the 'Ghostbuster' piece -- who you gonna call?" Kellogg said. ''You call the CDC."
A specimen would quickly be shipped, probably by plane, to the CDC in Atlanta for tests to corroborate the state finding.
''And imagine the day," Humes said with a sense of foreboding, ''when it's reported there's H5N1 in this country."