Agency Warns of Surge in Drug-Resistant TB

Tuberculosis may reach the point where most new cases in some countries are resistant to many drugs unless far greater efforts are made now to stop the spread of the infection, World Health Organization officials said yesterday.
That chilling forecast is based in part on the organization’s analyses showing that on average, a patient infected with drug-resistant tuberculosis in 2004 was resistant to more drugs than a similar patient with that diagnosis in 1994, Dr. Paul P. Nunn, a TB expert for the organization, said at a news conference.
The case of Andrew Speaker, the Atlanta man with extremely drug-resistant tuberculosis who took commercial flights for his wedding in Greece and honeymoon in Europe and set off an international health scare, has focused attention on the disease, and prompted the news conference.
Health officials say that Mr. Speaker’s was not an isolated case because the extremely resistant form has been reported in 37 countries. With the growth of international travel, health officials say that TB anywhere is TB everywhere. About 420,000, or 5 percent, of the estimated 8.8 million new cases of tuberculosis in the world are now resistant to many standard antituberculosis drugs, Dr. Mario C. Raviglione, who directs the W.H.O.’s tuberculosis department, said in an interview. About 30,000 of the 420,000 cases are extremely drug-resistant, meaning they are resistant to first-line and a number of second-line drugs.
Dr. Raviglione said the organization had begun to undertake statistical modeling studies to estimate how prevalent drug-resistant tuberculosis might become. Outcomes from such studies depend on a number of variables and none have been published. “It is possible that in some settings drug-resistant tuberculosis could completely replace standard tuberculosis,” Dr. Raviglione said.
That possibility is greatest in settings where poor public health services and laboratory facilities mean that no one knows the number and proportion of tuberculosis cases that are susceptible and resistant to drugs. In such areas, many people do not know they have tuberculosis.
An area of great concern is Africa, where AIDS patients often develop tuberculosis. Other areas are China, Eastern Europe and India.
Coughing, sneezing, singing and other activity spread the tuberculosis bacteria in the air. Anyone can become infected, but prolonged exposure is usually required.
Yesterday, the W.H.O. and a bipartisan group of United States senators called for more money to fight the disease.
The W.H.O., a United Nations agency in Geneva, said $1 billion would be needed each of the next two years. The agency has developed a plan to help countries better diagnose, treat and prevent drug-resistant tuberculosis that it said would save 134,000 lives in the next two years and 1.2 million lives by 2015.
In Washington, Senator Sherrod Brown, Democrat of Ohio; Senator Kay Bailey Hutchison, Republican of Texas; and Senator Edward M. Kennedy, Democrat of Massachusetts, have introduced a bill intended to fight the re-emergence of TB in this country and to combat it globally.
Many poor countries do not have sufficient monitoring systems for tuberculosis identification or laboratories that can detect drug-resistant forms. Also, researchers need to develop tests to detect the disease more quickly and new drugs to treat it, experts say.
Those efforts are needed because the overwhelming majority of standard tuberculosis cases can be cured, though treatment takes months, if not years.
But W.H.O. data shows that the cure rate drops to about 67 percent for multiple-drug-resistant cases and less than 30 percent for extremely resistant disease. Those numbers do not distinguish between otherwise healthy patients and those who have AIDS or other illnesses as well.
Mr. Speaker is being treated at the National Jewish Medical and Research Center in Denver, where Dr. Charles Daley, one of his doctors, said in a news conference that he may need surgery like many other patients with drug-resistant tuberculosis. But surgery is not an option for patients in most poor countries.

Drug-Resistant Tuberculosis Increasing From Use of Second-Line Drugs

March 23, 2007 — The March 23 issue of the Morbidity and Mortality Weekly Report (MMWR) describes 1993-2006 trends in extensively drug-resistant tuberculosis and in tuberculosis incidence in the United States."The worldwide emergence of extensively drug-resistant tuberculosis (XDR TB) and a provisional definition for this form of TB were first reported in November 2005," write N. S. Shah, MD, from Albert Einstein College of Medicine in Bronx, New York, and colleagues. "XDR TB presents a global threat and a challenge to TB-control activities in the United States. To prevent the spread of XDR TB, renewed vigilance is needed through drug-susceptibility testing, case reporting, specialized care, infection control, and expanded capacity for outbreak detection and response." The Emergency Global Task Force on XDR TB, convened by the World Health Organization in October 2006, revised the case definition to specify resistance to at least isoniazid and rifampin among first-line anti-TB drugs, resistance to any fluoroquinolone, and resistance to at least one second-line injectable drug (amikacin, capreomycin, or kanamycin).Using the revised case definition and provisional data for 2006, this report updates the 2006 report on XDR TB in the United States. The investigators analyzed US National TB Surveillance System (NTSS) data for reported XDR-TB cases from 50 states and the District of Columbia (DC) during 1993 to 2006. All culture-confirmed cases with initial drug-susceptibility test (DST) results reported for at least isoniazid and rifampin were included in the analysis.Of 49 cases (3% of evaluable multidrug-resistant [MDR] TB cases) meeting the revised case definition for XDR TB, 17 (35%) were reported during 2000 to 2006. Compared with cases identified during surveillance from 1993 to 1999, those from 2000 to 2006 were more likely to be in foreign-born persons and less likely to be in persons infected with human immunodeficiency virus (HIV). Of 202,436 culture-confirmed TB cases reported to NTSS during 1993 to 2006, 190,312 had initial DST results for at least isoniazid and rifampin, including 2927 cases (2%) with initial resistance to both drugs (MDR TB). Of 1665 (57%) of 2927 MDR-TB cases that had DST results reported for at least one fluoroquinolone and one injectable second-line drug, 49 cases (3%) met the revised definition of XDR TB, including 32 cases reported during 1993 to 1999 and 17 cases during 2000 to 2006. The 49 XDR-TB cases were reported from 9 states and 1 city, with the largest numbers reported from New York City (19 cases) and California (11 cases). Of 29 cases (59% of the 49 persons with XDR TB) for which HIV status was known, 16 (55%) were HIV-positive. Of 19 persons with XDR TB with known HIV status during 1993 to 1999, 14 (74%) were HIV-positive. Of 10 persons with known HIV status during 2000 to 2006, 2 (20%) were HIV-positive