Did you know Nigeria is one of the 22 countries with the highest rates of tuberculosis in the world?

Photo Credits: PBS, BBC

Name
Tuberculosis

Transmission

• Tuberculosis (TB) is a potentially serious disease caused by the bacteria Mycobacterium tuberculosis
• There are two types of TB infection:
  • ~1/3 of the world’s population is infected with the TB bacteria but not sick (called latent TB infection)
  • ~10% of those with latent TB infection will become ill (called active TB disease) and can then spread the disease to others
• Person-to-person transmission occurs through the air when people with active TB disease cough, sneeze, or spit and the TB bacteria are inhaled by another person
• TB mainly affects the lungs but can spread to other parts of the body

Geography
Worldwide

Incubation Period
No specified incubation period as some people live with latent TB infection without developing the full active TB disease

Signs and Symptoms

• Cough (may include blood or mucus)
• Fever
• Night sweats
• Weight loss
• Chest pain
• Weakness
• Lack of appetite

Diagnosis

• Skin test or a blood test
• TB is difficult to diagnose in children

Treatment
Usually involves a 6-12 month course of 4 standard (called first-line) antimicrobial drugs which must be taken exactly as they are prescribed

Resistance

• All over the world, there is an increasing prevalence of TB that is resistant to the drugs usually used to treat it
• This resistance falls into two categories:
  • Multidrug-resistant TB (MDR-TB): Develops when TB bacteria do not respond to the standard first-line TB drugs. A primary cause of MDR-TB is misuse of drugs or mismanagement of treatment. MDR-TB must be treated with second-line TB drugs, which are more expensive and have more side-effects, and MDR-TB can take at least three times longer to cure (18-24 months). A person with MDR-TB can directly infect others with MDR-TB.
  • Extensively drug-resistant TB (XDR-TB): A very serious disease that develops when second-line drugs are misused or mismanaged and therefore also become ineffective. People with XDR-TB have fewer and more toxic treatment options and poor outcomes. A person with XDR-TB can directly infect others with XDR-TB.

Prognosis

• Without treatment, 45% of people with active TB disease  will die
• The risk of death is higher for people living with HIV, malnutrition, diabetes, or other conditions that suppress their immune systems
• People living with HIV are 20 – 30 times more likely to develop TB and TB is a leading killer among this population (1 in 3 HIV deaths is due to TB)

Prevention: What Can You Do?

• Avoid close contact or prolonged time with known TB patients in crowded, enclosed environments
• If you know you have latent TB infection and you are at high risk of developing active TB disease, (if you are elderly, have HIV, malnutrition, diabetes, etc) speak with your healthcare provider about ways to prevent yourself from developing active TB disease

Sources:
http://www.cdc.gov/tb/topic/basics/default.htm
http://www.who.int/mediacentre/factsheets/fs104/en/
http://www.who.int/tb/areas-of-work/drug-resistant-tb/xdr-tb-faq/en/