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DURHAM, N.C. -- Less than 10 years ago, scientists were
predicting the imminent eradication of tuberculosis in the
United States. Now, due mainly to the rise of TB in people
living with HIV and the increase in immigration from Southeast
Asia and Africa, TB once again poses a serious threat to U.S.
public health.

North Carolina, whose incidence rate ranks in the middle of
the 50 states, has a number of counties -- concentrated in the
eastern portion of the state -- with TB incidence rates
rivaling the nation's largest cities.

The declining incidence of TB nationwide during the late
1980s and early 1990s was accompanied by a decrease in federal
spending on TB research and dwindling attention on the disease
from the medical community.

"We're now finding that many health care providers are not
adequately equipped to diagnose and manage patients with TB,"
said Duke University Medical Center TB specialist Dr. Carol
Dukes Hamilton. "The situation is especially true in rural
areas, where many providers have had minimal experience with
TB."

To address this emerging problem, the National Heart, Lung,
and Blood Institute awarded Hamilton and her Duke colleagues a
Tuberculosis Academic Award to develop strategies to improve
education for health care workers in the diagnosis and
treatment of TB.

The five-year, $375,000 award by the National Institutes of
Health agency is intended to help stem the rising incidence of
tuberculosis in the United States. Three such awards have been
granted each year for the past four years; the Duke award is
one of few dealing with TB in rural settings.

Hamilton anticipates that the Duke materials and strategies
can be used as a national model.

"TB is on the rise across the U.S., especially in the
heavily populated urban areas," Hamilton said. "North
Carolina's incidence is very interesting. While we rank 20th in
terms of statewide incidence, we have certain counties whose
incidence is as high as the urban areas such as New York or
Detroit."

In North Carolina, the TB incidence rate is the highest in
the eastern half of the state, Hamilton said. In descending
order, the top five counties with the highest incidence of TB
are Pitt (29.02 cases per 100,000 population), Lenoir (24.46),
Wilson (22.18), Robeson (20.43) and Johnston (14.96).

"Interestingly, at least six counties with the highest
incidence and the largest number of TB cases were not among the
top 10 counties in terms of population," Hamilton said.

Further compounding the problem in North Carolina is that
these rural areas are dramatically underserved by health care
providers, especially physicians, according to Hamilton.
Patients in these areas often are seen by family nurse
practitioners or physician assistants, who have minimal
training in infectious disease or pulmonary medicine, and who
are less likely to be able to travel to receive further
training.

Hamilton and colleagues will develop the educational
materials for improving TB education initially for Duke medical
students, house staff, nurses and physician assistants. Then,
aided by computer and Internet technology, the researchers plan
to take these newly developed educational tools to the
practitioners out in the rural communities.

According to Hamilton, three distinct factors have led to
marked increase in TB rates in the U.S.

"Probably the largest group get TB as a result of having
their immune system weakened by AIDS," she said. "While the
average person who has been exposed to TB has a 5 to 10 percent
lifetime risk of getting sick with TB, HIV-infected people who
have been exposed to TB have a 5 to 10 percent chance each year
of getting sick with it.

"Secondly, the U.S. has seen a dramatic increase in
immigration from Southeast Asia and Africa, where the TB rates
are very high," she continued. "Lastly, the general breakdown
in the fabric of society -- homelessness, poverty and drug
abuse -- is a major contributor to the spread of the
disease."

What makes the rise in TB so frustrating for physicians,
Hamilton said, is that it is usually completely curable with
drugs. However, the drugs must be taken every day for at least
six to 12 months to eradicate the disease, but many patients,
who can start feeling better within six weeks, stop taking the
medications too soon.

Studies have shown that if health care workers go to the
patients and observe them taking their medications, compliance
rates are much higher, Hamilton said. However, in rural areas,
where health care workers are already in short supply, this is
not a practical solution.

"Not only does this non-compliance with medications allow
the disease to return, but it also helps contribute to the
emergence of drug-resistant strains of TB," Hamilton said.
Trials are currently under way on a new anti-TB drug that only
needs to be taken once a week.