Tuberculosis (TB)

Tuberculosis, or TB, is typically caused by a bacteria known as Mycobacterium tuberculosis. TB usually affects the lungs, though it can affect other parts of the body, such as the spine, brain and kidneys. 

While TB is not common in the United States, it is very common in certain parts of the world. In fact, the World Health Organization (WHO) estimates that about a quarter of the world’s population has latent TB, which means they have been infected but are not ill or contagious. About 10% of these individuals will develop active TB disease, which is highly contagious. Since the year 2000, an estimated 83 million lives have been saved world-wide through effective testing and treatment programs. 

How Does TB Spread? 

TB spreads through the air when someone with active TB disease coughs, sneezes, spits, or sings. This releases tiny droplets into the air which contain the TB bacteria. When someone breathes these droplets, the bacteria enters the lungs and causes infection. 

Other forms of mycobacteria, such as Mycobacterium bovis, can also cause disease in humans. Mycobacterium bovis - or bovine tuberculosis - is a strain of TB that usually affects cattle. People can also become infected with this strain, typically through consuming unpasteurized (raw) milk products. This strain of TB is far less common in the United States, thanks to pasteurization and disease control in cattle herds. 

With the increasing popularity of raw milk in the US, individuals should be advised that consumption of unpasteurized milk carries significant risk of multiple, serious infectious diseases. For this reason, raw milk and raw milk products should not be consumed. 

TB is not spread by casual touch, like shaking hands, hugging, kissing, or sharing food or drink. Likewise, it is not spread by touching something that someone with TB has been in contact with, such as toilet seats or bed linens. 

Active vs. Latent TB

Not everyone infected with TB bacteria becomes sick, or is contagious to others. 

Latent TB occurs when the bacteria is present in the body, but the immune system is able to keep it under control. Individuals with latent TB have no symptoms and are not contagious to others. You cannot get TB from someone who has latent TB. Without treatment, latent TB can develop into active TB disease. 

Active TB disease occurs when the immune system is not able to control the bacteria. The bacteria multiplies and spreads, causing people to feel sick. People with active TB disease are contagious to others. Without treatment, active TB disease can be fatal.   

What are the Symptoms?

People with active TB disease may have: 

  • Prolonged cough (over three weeks)
  • Coughing up blood or sputum (phlegm from deep inside the lungs) 
  • Chest pain
  • Weakness or fatigue
  • Weight loss and loss of appetite
  • Chills 
  • Fever
  • Night sweats

Symptoms may be mild for several months and are also very similar to other respiratory infections, such as influenza. This can lead to delays in seeking care, and an increased risk of spreading the infection to others. 

Who Should be Tested? 

Individuals with an increased risk should be screened for TB. This includes: 

  • Healthcare professionals
  • Individuals who were born in, frequently travel to, or have spent an extended amount of time (more than a typical vacation) in a country where TB is common. 
  • Individuals who live or work in large group settings where TB is more likely to spread, such as shelters or correctional facilities. 

Many healthcare programs at Weber State require students to have a recent TB test prior to starting clinical rotations. These requirements are set by the individual programs and are outlined in your student handbook. 

In addition, international students from high-incidence countries are encouraged to be screened for TB within their first semester on campus. 

Students who participate in a short-term travel program, such as Alternative Spring Break, likely do not need to be screened for TB upon your return. Students who spend a semester abroad in a high-incidence country should consider testing when you return. 

How is it Tested? 

TB may be tested using either a skin or blood test. 

A TB skin test uses a small needle to inject a tiny amount of a substance called tuberculin just below the skin of your forearm. You will need to return to the clinic within 48-72 hours to check for swelling at the injection site. 

A TB blood test uses a blood sample to determine if TB bacteria is present. 

A positive blood or skin TB test indicates that the bacteria is present in your body, though additional testing is needed to determine if it is active or latent. This may include a chest x-ray and testing of the sputum (phlegm) you cough up. 

Many countries vaccinate infants and small children with the bacille Calmette-Guerin (BCG) vaccine. The BCG vaccine may cause a false-positive TB skin test reaction. If you were vaccinated as a child, blood testing is recommended. 

Both TB skin and blood tests are available free of charge for WSU students through Ogden Clinic. No appointment is needed for currently registered students. 

If TB testing indicates a potential infection, simple x-ray films are also covered for WSU students through Ogden Clinic. If an infection is confirmed, Ogden Clinic physicians will assist you in understanding your treatment options. The cost of medications is not covered by the university, though there may be assistance programs available through your local health department. 

How is TB Treated? 

Treatment is recommended for both the latent and active forms. 

TB is curable with antibiotics, though the bacteria is strong. It can take a long time and several types of antibiotics to kill the bacteria. Treatment for TB can last for three to nine months, depending on whether it is latent or active, and whether you have a drug-resistant strain or not. 

If you have latent TB, treatment is the best way to prevent it from progressing into active TB disease, and potentially spreading to others. Treating TB in the latent stage is also easier, potentially requiring less time on antibiotics and less types of antibiotics. 

It is very important to take all medication as prescribed, and for as long as prescribed, to fully clear the bacteria.Not taking all of your medication can lead to drug-resistant strains of bacteria, which make the disease harder to treat in the future. 

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