By Fia Curley

Tuberculosis, or TB, is striking a hard blow to minority communities in U.S., while progress is slowing in efforts to eliminate tuberculosis in the country, according to a new CDC’s Morbidity and Mortality Weekly Report.

Surveillance data show that national TB rates fell to an all-time low of 4.6 cases per 100,000 people in 2006 -- a total of 13,767 active cases. But, the decline in the TB rate in 2006 (3.2 percent) was one of the smallest in more than a decade.

According to the report, in 2006, Asians were 21 times more likely to have TB than whites, and blacks and Hispanics were about eight times more likely to have TB. Foreign-born individuals accounted for more than half of all TB cases in the United States in 2006. This group of people had a TB rate nearly 10 times higher than U.S.-born individuals (21.9 vs. 2.3 cases per 100,000), the report said.

"It's a disease of minorities, immigrants, inner-city African Americans and Hispanics and the homeless," said Dr. Masae Kawamura, director of TB Control Section of San Francisco Department of Public Health and the co-principal investigator for the Francis J. Curry National TB Center. "You can't get enough attention to it, unfortunately, in these populations; their priorities are not their health but getting shelter."

Due to drug-resistant strains and its lethal partnering with HIV, the World Health Organization (WHO) has placed even more urgency behind the goal of stopping TB by 2015.

Although TB rates in the United States are lower than those in other countries, a 1980's surge in the numbers has pushed the disease back to the forefront, in particular due to its disproportionate burden in ethnic and racial minorities.

When substance abuse, poverty and crowding in cheap hotels are added into the urban mix, transmission occurs naturally, Kawamura said, emphasizing the importance of "thinking TB."

"All providers caring for minorities need to think TB. Otherwise it will never be diagnosed and they're at the front line of protecting the community," she said. "Until you get to that level, it's hard to get people screened."

Tuberculosis is an infectious disease usually spread though the air when a person who is sick with TB expels the germs to another person by talking, singing, spitting, laughing, sneezing or coughing.

Known as consumption during the early 19th century, the disease caused public concern as it was quickly spread throughout communities of the urban poor. By the 1960s, TB had been vastly eliminated in the US. However, by the 1980s, homelessness and poverty due to HIV, along with under-funded TB programs and immigration caused rates to spike, Kawamura said.

The WHO estimates that a person who is sick from TB can infect an average of 10 to 15 people a year. However, every person who inhales the germs does not become sick. After the germs are inhaled from a sick person, they can lie dormant in the lungs as a person's immune system prevents multiplication. The germs can remain inactive for years and the person lives symptom-free, but a breakdown of the immune system can trigger multiplication and sickness. This is why the focus is on the foreign-born who show signs of active TB five years after immigrating, Kawamura said.

Symptoms can include weight loss, a weak or sick feeling, fever and night sweats. If the disease has infected the lungs, chest pains, a persistent cough that remains for weeks and coughing up blood may also be symptoms.

TB germs can also affect other parts of the body, such as the brain, spine and kidneys when the disease is carried through the bloodstream. If left unchecked, the result could be death.

The silver lining of the situation is that vaccines to cure TB were developed in the early 20th century at the Pasteur Institute in France. A single antibiotic shot will cure dormant strains of TB while a series of shots over a six to 12 month period will cure a person sick with TB. The dark cloud returned when several strains of TB began resisting drugs. Strains begin to mutate and resist drugs because antibiotics are not taken as directed, for instance, when people discontinue treatment because symptoms have subsided or take medicine at unscheduled times.

Couple the issue of drug-resistant TB strains with HIV infection and the scenario proves lethal with almost a 100 percent mortality rate.

HIV, which weakens the immune system, allows the TB to become active. Each disease feeds off of the other, speeding along the process of AIDS. TB kills up to half of all AIDS patients worldwide. People who are HIV-positive and infected with TB are up to 50 times more likely to develop active TB in a given year than people who are HIV-negative.

"It's like throwing gasoline on a fire," Kawamura said. "It leads to disease progression, exposure of other individuals, and then you have outbreaks."

Francis J. Curry National TB Center follows the patient-centered Directly Observed Therapy Strategy (DOTS), which, Kawamura said, treats patients like people, not diseases.

In order to prevent outbreaks and the early onset of AIDS in HIV positive individuals, staff members administer TB vaccines three times a week or more, until they have finished treatments to about 50,000 clinic visitors a year in the San Francisco TB Center.

"It's very important that you have all the pieces to fight TB," Kawamura said. "We have all kinds of tricks to get them to come in—food, bus tokens—but in the end it's all about the relationship. It's about making the patient a VIP, creating a relationship with the patient, and taking them through the long process."

Regardless of funding changes and spikes or declines in the TB rate, Kawamura said the center's staff will remain diligent, promoting TB testing and patient-centered DOTS.

"When you see public health in action you see the difference it makes in people's lives," Kawamura said. "When you see people come in for TB and recover from TB, that's enough motivation. To do that—to see people on death's door recover—it really helps build the communities to make people feel they have a health organization that cares about them."

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Fia Curley is a writer for the OMHRC. Comments? Email: fcurley@omhrc.gov

Links

NIAID Statement on World TB Day
http://www.omhrc.gov/templates/content.aspx?ID=498

CDC TB statistics and facts
http://www.cdc.gov/nchstp/tb/pubs/dtbefax.htm

10 Facts about Tuberculosis
http://who.int/features/factfiles/tuberculosis/en/index.html

Trends in Tuberculosis Incidence --- United States, 2006
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5611a2.htm

Tuberculosis vaccination
http://www.omhrc.gov/templates/content.aspx?ID=3939

Tuberculosis: A Guide for Adults and Adolescents with HIV
http://www.cdc.gov/hiv/pubs/brochure/oi_tb.htm

About Tuberculosis
http://www.stoptb.org/stop_tb_initiative/abouttb.asp

Tuberculosis
http://www.who.int/mediacentre/factsheets/fs104/en/index.html

TB/HIV
http://www.who.int/tb/hiv/faq/en/index.html

TB/HIV links
http://www.who.int/tb/hiv/links/en/index.html

TB diagnosis and treatment
http://www.nationaltbcenter.edu/abouttb/diagnosis_and_treatment.cfm