No active TB cases found yet after scare

Public health authorities have found no evidence so far that anyone who had contact with a junior doctor infected with tuberculosis has developed an active, contagious case of the bacterial illness, authorities said yesterday.

More than 3,300 patients and healthcare workers have been evaluated in the past two weeks for telltale signs of the disease, including cough, high fever, chills, and fatigue. None of those examined reported being beset with such symptoms.

Tuberculosis spreads only when someone is symptomatic.

''The fact that we have found no active cases to date is reassuring," said Dr. Anita Barry, top disease tracker at the Boston Public Health Commission. ''But we do also have patients out there who have not responded to requests to come in and be tested. It's for their own health that we would like them to come in."

In Boston alone, about 2,200 healthcare workers and patients have been evaluated. Still, health authorities estimate that's just half of those who should be seen.

The junior physician, a surgical resident, rotated through five hospitals: Boston Medical Center, the VA hospitals in Jamaica Plain and West Roxbury, Brockton Hospital, and Cape Cod Hospital.

Disease investigators have said they believe the woman was infectious from Dec. 1, 2004, until June 2, when she was removed from treating patients. Authorities have not released her identity, citing federal laws prohibiting the disclosure of patient information.

As part of the evaluation of patients and health workers who may have had contact with the doctor, skin tests are being administered that show whether an individual has been exposed to TB.

Cape Cod Hospital officials said yesterday that six of 140 patients tested have shown signs of TB exposure.

''But none of the six show any signs or symptoms of TB," said David Reilly, a hospital spokesman.

Patients and healthcare workers who have a positive skin test are sent for further evaluation, including a chest X-ray, to determine whether they have a contagious case of TB. Studies have shown that 90 percent of people with a positive skin test never become ill and, thus, do not pose a health threat.

Authorities from the Boston Public Health Commission acknowledged that some of those who received the skin exam in Boston also tested positive. Representatives of the agency said they expected within a week to release a detailed report on how many people tested positive and whether their exposure probably stemmed from contact with the doctor.

Figuring that out, though, is a daunting proposition. It involves scouring medical records and testing logs from an array of sources, looking to determine whether a patient or healthcare worker tested positive earlier on the skin test, known as a PPD.

Federal disease specialists estimate that if TB skin tests were administered randomly to US adults, 5 to 10 percent would test positive.

''And many times, there's just no way to know when that infection actually occurred," said Sue Etkind, director of the state's division of tuberculosis prevention and control.

Stephen Smith can be reached at stsmith@globe.com.