What is Tuberculosis?
Tuberculosis (TB) is an infectious illness that normally affects the lungs, though it can affect any organ in the body. It may develop when bacteria spread through droplets in the air. TB can be fatal, but in most cases, it is preventable and treatable.
In the past, TB, also called “consumption,” was a major cause of death globally. With improvements in living conditions and the development of antibiotics, the prevalence of TB reduced dramatically in industrialized countries.
However, in the 1980s, numbers started to increase again. The World Health Organization (WHO) termed it an “epidemic.” They report that it is among the top ten causes of death globally and “the principal cause of death from a single infectious agent.”
As per WHO estimates in 2018, about 10 million people developed TB around the world and 1.5 million people died from the infection including 251,000 individuals who also had HIV.
The largest number of the people affected were in Asia. However, TB remains an issue of concern in many other areas, including Nigeria.
Presently, antibiotic resistance is causing renewed worries about TB among experts. Some strains of the disease are not responding to the most effective treatment available. In this case, TB is hard to treat.
· An individual with TB may experience swollen lymph nodes.
· An individual may develop TB after inhaling Mycobacterium tuberculosis (M. tuberculosis) bacteria.
· When TB affects the lungs, the infection is the most contagious, but a person will usually only become sick after close contact with somebody who has this type of TB.

TB infection (latent TB)
An individual may have TB bacteria in their body and never develop symptoms. In most persons, the immune system can contain the bacteria so that they do not multiply and cause disease. In this case, a person will have a TB infection but no active disease.
Doctors describe this as latent TB. A person may not experience symptoms and be unaware that they have the infection. There is also no risk of spreading a latent infection to another person. However, a person with latent TB still needs treatment.

TB disease (active TB)
The body may not be able to contain TB bacteria. This is mainly common when the immune system is weakened as a result of illness or the use of certain medications.
When this occurs, the bacteria can replicate and cause symptoms, leading to active TB. People with active TB can pass on the infection.
With no medical intervention, TB becomes very active in 5–10% of people with the infection. In about 50% of these people, the progression happens within 2–5 years of getting the infection, according to the CDC.
The possibility of developing active TB is greater in:
• Someone with a weakened immune system
• Someone who first developed the infection in the past 2–5 years
• Older adults and younger children
• People who use injected recreational drugs
• People who have not received proper treatment for TB in the past

Early warning signs of Tuberculosis
A person should visit a doctor if they notice:
• A persistent cough, lasting for about 3 weeks
• Phlegm, which may contain blood in it, when they cough
• A loss of weight and appetite
• A general feeling of tiredness and being sick
• Swelling around the neck
• A fever
• Night sweats
• Chest pain

Symptoms of Tuberculosis
Latent TB: A person with latent TB will not have symptoms, and no damage will appear on a chest X-ray. However, a blood test or skin prick test will show that they have a TB infection.

Active TB: People with TB disease might notice a cough that produces phlegm, fatigue, a fever, chills, and a loss of appetite and weight. Symptoms typically worsen with time, but they can also spontaneously go away and come back.

Beyond the lungs
TB typically affects the lungs, though symptoms can arise in other parts of the body. This is mainly common in people with weakened immune systems.
TB can cause:
• Consistently swollen lymph nodes, or “swollen glands”
• Abdominal pain
• Joint or bone pain
• Confusion
• A persistent headache
• Seizures

Diagnosis for Tuberculosis
People with latent TB will have no symptoms, but the infection can be detected on tests. People should request for a TB test if they:
• have spent time with anyone who has or is at risk of TB
• have spent time in places with high rates of TB
• Work in an environment where TB is present

You will ask about any symptoms and the person’s medical history. Physical screening will also be carried out which involves listening to the lungs and checking for swelling in the lymph nodes.

Two tests can detect whether TB bacteria are present:
• The TB skin test
• The TB blood test
However, these will not indicate if TB is active or latent. To test for active TB disease, the doctor will suggest a sputum test and a chest X-ray.
Everybody with TB needs treatment, regardless of whether the infection is active or latent.

Treatment for Tuberculosis
With early detection and correct antibiotics, TB is treatable.
The right type of antibiotic and duration of treatment will depend on:
• Age along with the general health of the person
• If they have latent or active TB
• The location of the disease
• If the TB is drug-resistant

Treatment for latent TB can differ. It may involve taking an antibiotic once a week for 12 weeks or daily for 9 months.
Treatment for active TB may require taking several drugs for 6–9 months. When an individual has a drug-resistant strain of TB, the treatment will be very complex.
It is important to complete the full course of treatment, even if symptoms disappear. If a person stops taking their medication early enough, some bacteria can survive and turn resistant to antibiotics. In this case, the person can go on to develop drug-resistant TB.
Depending on the parts of the body that TB affects, a medical doctor may also prescribe corticosteroids.

Causes of Tuberculosis
M. tuberculosis bacteria cause TB. They can be transmitted through the air in droplets when an individual with pulmonary TB coughs, sneezes, spits, laughs, or talks.
Only persons with active TB can transmit the infection. However, many people with the disease can no longer transmit the bacteria after they have gotten appropriate treatment for at least 2 weeks.

Prevention of Tuberculosis
Measures for preventing TB from infecting others include:
• Getting a diagnosis and receiving treatment on time
• Staying clear from other people until there is no more risk of infection
• Using a mask, covering the mouth, and ventilating rooms
TB vaccination
In some countries including Nigeria, children receive an anti-TB vaccination — the bacillus Calmette–Guérin (BCG) vaccine — as part of a normal immunization program.
However, experts from the Western world do not recommend BCG inoculation for most people unless they have a great risk of TB. Some of the reasons include a minimal risk of infection in the country and a high possibility that the vaccine will interfere with any future TB skin tests.

Risk factors of Tuberculosis
Persons with weakened immune systems are very likely to develop active TB. The following are some conditions that can weaken the immune system.
HIV
For people who have HIV, doctors consider TB to be an opportunistic infection. This means that a person with HIV has a greater risk of developing TB and experiencing very severe symptoms than a person with a healthy immune system.
Medication for TB can be complex in a person with HIV, but a doctor may develop a comprehensive treatment plan that addresses the two issues.
Smoking
Tobacco use and secondhand smoke raise the risk of developing TB. These factors also make the disease difficult to treat and more likely to return after treatment.
Quitting smoking and avoiding contact with smoke can lower the risk of getting TB.
Other conditions
Some other health conditions that weaken the immune system and can increase the risk of getting TB include:
• Low body weight
• Substance abuse disorders
• Diabetes
• Silicosis
• Serious kidney disease
• Head and neck cancer
Also, some clinical treatments, such as organ transplants, stop the functioning of the immune system.
Spending time in a country where TB is common can also increase the likelihood of developing it.
Complications of Tuberculosis
Without any treatment, TB can be fatal. If it spreads throughout the body, the infection can lead to problems with the cardiovascular system and metabolic function, among other issues.
TB can also cause sepsis, a potentially life-threatening type of infection.

Outlook
An active TB disease is contagious and potentially life-threatening if an individual does not receive appropriate treatment. However, most cases are treatable, especially if the doctors detect them early.
Anyone with a great risk of developing TB or any symptoms of the disease should see a doctor immediately.