One out of every 10,000 people in the US is infected with tuberculosis. The Asian American population has the highest tuberculosis case rate of any ethnic group: 24 times greater than Caucasians. Additionally, 80% of the population in many Asian countries test positive in tuberculin tests, while only 5-10% of the US population test positive.
One-third of the world’s population have been exposed to tuberculosis. 8 million people a year will progress into active tuberculosis and 2 million will die from the disease worldwide. 80% of the population in many Asian and African countries test positive in tuberculin tests, while only 5-10% of the US population test positive. However, tuberculosis is becoming a greater concern in the US as immune systems are weakened by immunosuppressive drugs, substance abuse and AIDS.
Pulmonary tuberculosis is a contagious bacterial infection primarily affecting the lungs. its primary stages, tuberculosis is asymptomatic. The majority of the people in the US who contract tuberculosis will recover during the primary stages, never showing signs of the infection again. About 90% of those infected have a asymptomatic, latent tuberculosis infection with only a 10% chance that it will progress to the active disease in their lifetimes.
Active Pulmonary tuberculosis develops in the small percentage of people who have compromised immune systems (elderly, infants, those with AIDS, etc). The active disease may occur within weeks after initial exposure. It can also lie dormant for years only to reappear after the initial infection has already been contained. For those cases that eventually develop into the active disease, tuberculosis kills over half of its victims.
A sneeze, cough or spit from a person suffering from active tuberculosis expels tens of thousands of infectious droplets of the disease. The inhalation of just one of these droplets can cause a new infection. The probability of infection is dependent on several factors: the number of infectious droplets expelled by the carrier, the quality of ventilation, the duration of exposure and the particular strain of the disease. Prolonged contact with an infected person faces a 22% infection rate.
People carrying the active disease but are undergoing drug therapy usually cease to be contagious after two weeks. With someone newly infected, it will take at least 21 days up to a month from exposure before the person becomes contagious. Tuberculosis can also be transmitted by eating meat infected with the disease. Transmission can only occur from people with active—not latent, tuberculosis.
Prevention
Have a well-rounded diet. Recent studies have shown a link between vitamin D deficiency and an increased risk of contracting tuberculosis. Other micronutrient deficiencies, like iron and vitamin B12, may contribute to an increased risk.
Quit smoking. Smoking more than twenty cigarettes a day increases the risk of tuberculosis by two to four times.
While a BCG vaccination is available, it is usually given to people living in countries with a high incidence of tuberculosis, and its effectiveness is variable by age. It is over 80% effective for children but its efficacy in adolescents and adults range from 0 to 80%.
Get tested. Preventative therapy is available for those with a positive skin test but have not progressed into active tuberculosis. If it is not treated early, tuberculosis can cause permanent lung damage.
Symptoms
Symptoms for tuberculosis may include: coughs and mild fever, fatigue, unintentional weight loss, coughing up blood, fever and night sweats, phlegm-producing cough, wheezing, chest pain and difficulty breathing.
Treatment
Initial treatment consists of daily doses of a combination of antitubercular drugs until results reveal drug sensitivity to the infection. Treatment is typically continued for another six months. Hospitalization, to prevent the spread of the disease is sometimes required until the contagious period ends with treatment.
Incomplete treatment of tuberculosis, usually due to a failure to take the medications for the prescribed length of time can lead to the development of drug-resistant strains of the bacteria.
All medications used to treat tuberculosis have a degree of toxicity. Rifampin and isoniazid may cause non-infectious hepatitis. Ethambutol sometimes affects the vision of the patient.
