June 8th, 2007 05:17 EST
Global Disease Issues: U.S. Tuberculosis Case Raises Questions
Washington – The 12-day international journey of a U.S. man with a rare form of tuberculosis (TB) has ended with the patient in hospital isolation, congressional hearings into U.S. public health processes and many questions about a new strain of an old disease.
Government officials testified June 4 before a Senate Appropriations subcommittee about how someone with a potentially infectious disease could travel on commercial airline flights to and from Europe and cross the border from Canada into the United States.
The complex story – now the subject of internal investigations by the U.S. Centers for Disease Control and Prevention (CDC) and U.S. Customs and Border Protection – involves the airborne infectious disease tuberculosis.
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told the subcommittee that TB is “one of a group of diseases that continue to persist, emerge and re-emerge in the form of multiple-drug-resistant microbes.”
Globally, nearly 9 million people get TB each year, and 1.6 million die as a result. One-third of the world’s population is infected with latent (inactive) TB, but the disease usually does not become active unless something reduces a person’s immunity – a disease like AIDS, advancing age or some medical conditions.
TB is treated with a six- to nine-month course of “first-line” (the most effective) drugs. If patients do not complete the drug course or are treated improperly, they can develop a multidrug-resistant (MDR) form of the disease.
Those with MDR TB must be treated with more expensive, less effective second-line drugs for 18 to 24 months. If they do not complete this course or are treated with the wrong drugs, they can develop extensively drug resistant (XDR) TB, whose bacteria strains are resistant to first- and second-line drugs.
Fewer than 30 percent of XDR TB patients – like 31-year-old Georgia lawyer Andrew Speaker – who are otherwise healthy and whose immune systems are not compromised, can be cured. More than half of those with XDR TB die within five years of diagnosis. There might be 50,000 cases of XDR TB worldwide.
Speaker’s first diagnosis, in May, was of MDR TB. His TB test, doctors said, was “smear negative, culture positive.” This means that when his respiratory secretions were put into a culture medium, tuberculosis bacteria grew, but when they were smeared on a microscope slide, no bacteria were visible.
“Smear negative-culture positive patients generally pose a very low hazard of transmission,” CDC Director Dr. Julie Gerberding told the subcommittee, “but it’s not zero.”
Speaker’s sample went to CDC for further tests. In the meantime, Speaker said, he was told repeatedly that he was not contagious – not a danger to anyone. He was advised not to travel and to seek treatment at the National Jewish Medical and Research Center in Colorado, a leader in treating lung diseases.
Speaker learned it would take two to three weeks to get into the center, so the lawyer, whose wedding in Greece was less than two weeks away, took a commercial flight to Europe May 12.
On May 22, the CDC lab determined that Speaker had XDR TB, and CDC officials tried to find him. They did not know how contagious he was, but they had to assume the worst. CDC also contacted U.S. Customs and Border Protection to have Speaker’s name put on a lookout list at all U.S. entry points.
Later that day, Speaker contacted CDC from Italy, willing to cooperate. His options, among others, were to check into an Italian hospital or pay more than $100,000 for an air ambulance. CDC’s own aircraft could not be made safe to transport a patient who, they thought at the time, needed respiratory isolation.
Speaker and his new wife decided to get back to the United States and traveled by commercial airliner from the Czech Republic to Canada. There, on May 24, a border guard ignored the lookout advisory and let Speaker and his wife into the country.
CDC reached Speaker on his cell phone May 25 and directed him to Bellevue Hospital in New York City, where he was served with a federal order of isolation – the first one issued since 1963, when an order was issued for a smallpox case. By May 31, Speaker was in isolation in Colorado, where he remains.
Speaker says he might have gotten TB during a five-week humanitarian visit to Vietnam with the Rotary Club in 2006, or during a 2001 trip to Peru.
“We have millions of people around the world crossing borders every day, many of them with TB or other infectious diseases,” Dr. Nils Daulaire, president of the nongovernmental organization the Global Health Council, told the subcommittee. “Unless we address the problems of these diseases at their source, in the world’s poorest communities, no walls we can build will be high enough to protect the American population.”
Internal reviews are ongoing at CDC to determine what procedures are needed to deal with similar cases in the future.
More information about tuberculosis and TB research is available at the NIAID Web site.
Answers to frequently asked questions about XTR TB are available at the World Health Organization Web site.
(USINFO is produced by the Bureau of International Information Programs, U.S. Department of State. Web site: http://usinfo.state.gov)
By Cheryl Pellerin
USINFO Staff Writer