The National Tuberculosis Day was observed on Aug. 19 in the Philippines to raise our awareness about a disease that has devastating health, social, and economic consequences.
One of our professors in medical school said “You are not a Filipino if you do not have tuberculosis.” That was more than three decades ago and it may have been an overstatement but it impressed in our minds that tuberculosis (TB) was then a prevalent infection in our country. Unfortunately, it still is prevalent and is a leading cause of death in adults not only in our country but also worldwide.
In a study by Gabrielle P. Flores et al. published in the medical journal Lancet in January 2022, the Philippines ranks fourth in TB incidence worldwide. About one million Filipinos have active TB and nearly 70 Filipinos die every day from TB, a preventable and treatable disease.
In its report dated Oct. 14, 2021, the World Health Organization stated that in 2020, 30 countries accounted for 86 percent of new (incident cases) TB patients. Of these, eight countries alone accounted for two-thirds of total new cases worldwide – India was the leading country, then China, Indonesia, Philippines, Pakistan, Nigeria, Bangladesh, and South Africa.
The Philippines in 2016 created a high-level national coordination committee whose members are secretaries of various government agencies and heads of private organizations.
The Department of Health has an Updated Philippine Strategic TB Elimination Program (Phase 1: 2020-2023) and has intensified its campaigns on information, screening, and treatment.
The theme of the United Nations General Assembly held in New York, U.S.A. in September, 2021 for TB control was “ United to end tuberculosis: An urgent global response to a global epidemic.”
TB as an epidemic is defined as a disease that affects a large number of people in a certain population, community, or region. It still affects several populations especially in underdeveloped nations. It is not only a health concern, but a socio-economic one as well.
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TB is caused by the rod-shaped bacterium Mycobacterium TB. Inhalation of infected aerosol droplets may lead to immediate clearance of the organism in 90 percent of cases. A primary active disease with immediate onset of symptoms develops in five to 10 percent, while other patients develop a latent or silent infection. This latent TB becomes an active disease when the affected person’s immune defense becomes weak. Reactivation of the bacteria can occur in five to 10 take years but can lead to symptomatic and progressive disease.
The major site for primary infection and TB disease are the lungs. Complications of TB of the lungs include the following: hemoptysis or coughing up of blood, pneumothorax or the release of air into the lung cavity from a damaged portion of the lung, extensive scarring of the lungs, respiratory failure, septic shock due to severe infection, and chronic infection of the lungs with a mold or fungus (Aspergillosis).
A study by the U.S. National Cancer Institute showed pulmonary TB was associated with an increased risk of lung cancer after adjustment for active lung smoking and socioeconomic status.
Another study in China showed TB was associated with a 1.78 fold increase in the risk of lung cancer among nonsmokers and an association with adenocarcinoma. This association is thought to be mediated by the immune and chronic inflammatory response brought about by TB infection. The cell walls of the organism causing TB are also thought to induce production of substances (Example: reactive oxygen species) that damage a person’s DNA.
TB can also affect other organs like the heart and cause tuberculous pericarditis, the skin, the lymph nodes, the brain (tuberculous meningitis), stomach, and intestines.
Treatment takes a long time and some strains are resistant to commonly used drugs. Residual scarring even after treatment can be a cause of functional and physical disability. (Sources: World Health Organization and Department of Health websites, UpToDate, Medscape)