Practical Practitioner

By: Pamela Egan, FNP-C CDE

Tuberculosis is still a global concern

Dear Pam,

One of the foreign students at my son’s college came down with Tuberculosis. The school is now requiring that all students be screened. Is TB making a comeback?

Tuberculosis is reappearing in many countries as a public health crisis.

Though ancient, it is not a disease of the past. A staggering 1.9 million around the globe die of tuberculosis each year- another 1.9 billion are infected with Mycobacterium tuberculosis and are at risk for active disease.

In the 20th century, the United States made impressive strides in tuberculosis control. In 1985, however, the United States saw a reversal in this long-standing downward trend, and tuberculosis reemerged as a public health threat. From 1985 to 1992, not only did the number of cases increase from 22,202 to 26,673, but also large outbreaks were reported. Many of these, especially in hospitals and other health-care settings in large cities, were caused by multidrug-resistant M. tuberculosis. Several factors contributed to this increase, including the emergence of the HIV epidemic and large influxes of immigrants from countries in which tuberculosis was common.

In 2001, the 15,989 tuberculosis cases reported to CDC represented only a 2 percent percent decline from 2000, the smallest decline in nine years. These numbers may be the first sign that our control efforts are failing. The proportion of cases in persons born outside the United States is growing. In 2001, that figure reached 50 percent. Another risk, in the current climate of bioterrorism, is the possible intentional spread of multidrug-resistant M. tuberculosis. This risk requires new tools for detection and rapid and effective response.

Tuberculosis, commonly referred to as TB, is a bacterial infection that can spread through the lymph nodes and bloodstream to any organ in your body but is usually found in the lungs. Most people who are exposed to TB actually never develop symptoms. The bacteria can live in an inactive form in the body. Medication can be given to help get rid of the inactive bacteria. However, if the immune system weakens, such as in people with HIV or as we age, the bacteria can activate. In their active state, TB bacteria cause death of tissue in the infected organs, possibly resulting in death.

Because the bacteria that cause tuberculosis are transmitted through the air, the disease can be quite contagious. Tuberculosis is generally caused by exposure to microscopic airborne droplets containing the bacterium Mycobacterium tuberculosis. The disease is almost never transmitted through clothes, bedding or other personal items. Because most people with TB exhale only a few of these germs with each breath, you can contract the disease only if you are exposed to an infected person for a long time.

People who are malnourished or who live in close quarters stand the greatest chance of contracting tuberculosis. Therefore, dormitories face a greater-than-normal risk of becoming infected with TB. By all means, encourage your son to receive the Tuberculin skin test at college.

Because the bacteria generally stay dormant after they invade the body; only 10 percent of people infected with TB will ever come down with the active disease. The remaining 90 percent will show no signs of infection, nor will they be able to spread the disease to others. Dormant infections can eventually become active, though, so even people without symptoms should receive medical treatment. The active form of the infection is more likely to occur in people with weakened immune systems such as those with AIDS, or blood cancers such as leukemia.

Once widespread, TB became relatively rare with the help of antibiotics developed in the 1950s. Today, however, a new and highly resistant form has emerged, creating a public-health hazard in many large cities worldwide. If you have TB- in its active or dormant state- you must seek medical treatment.

This article was originally published December 16, 2002 in The St. Tammany News.

PamelaEgan.com > Health Articles > Disease