Tuberculosis Risk factors

Anyone of any age, race or nationality can contract TB, but certain factors increase your risk of the disease. These factors include:

• Lowered immunity. When your immune system is healthy, macrophages can often successfully wall off TB bacteria, but your body can't mount an effective defense if your resistance is low. A number of factors can weaken your immune system. Having a disease that suppresses immunity, such as HIV/AIDS, diabetes or the lung disease silicosis, and receiving treatment with corticosteroids, arthritis medications or chemotherapy drugs can damage your body's ability to protect itself.
• Close contact with someone with infectious TB. In general, you need to spend an extended period of time with someone with untreated, active TB to become infected yourself. You're most likely to catch the disease from a family member, roommate, friend or close co-worker.
• Nationality. People from regions with high rates of TB — especially Africa, Asia and Latin America, and in the case of MDR-TB, the former Soviet Union — are more likely to develop TB.
• Age. Older adults are at greater risk of TB because normal aging or illness may weaken their immune systems. They're also more likely to live in nursing homes, where miniepidemics of TB can occur.
• Substance abuse. Long-term drug or alcohol use weakens your immune system and makes you more vulnerable to TB.
• Malnutrition. A poor diet or one too low in calories puts you at greater risk of TB.
• Lack of medical care. If you are on a low or fixed income, live in a remote area, have recently immigrated to the United States, or are homeless, you may lack access to the medical care you need to diagnose and treat TB.
• Living or working in a residential care facility. People who live or work in prisons, immigration centers or nursing homes are all at risk of TB. That's because the risk of the disease is higher anywhere there is overcrowding and poor ventilation.
• Living in a refugee camp or shelter. Weakened by poor nutrition and ill health and living in crowded, unsanitary conditions, refugees are at especially high risk of TB infection.
• Health care work. Regular contact with people who are ill increases your chances of exposure to TB bacteria. Wearing a mask and frequent hand washing greatly reduce your risk.
• International travel. As people migrate and travel widely, they may expose others or be exposed to TB bacteria.