A potentially serious infectious bacterial
disease that mainly affects the lungs
Tuberculosis
Tubercule :
Osis :
Round
Condition
nodule
Cause :
• mycobacterium
tuberculosis
(in humans)
• mycobacterium bovis
(in animals)
Mycobacterium Tuberculosis - Characteristics
• Gram positive
• Obligate Aerobe
• Non spore forming
• Non motile rod
• Mesophile
• Generation time – 15 to 20 hrs
• Lipid rich cell wall
How TB
affects
Epidemiology
Incidence of TB in India
Treatments that we know of -
Yet to be Solved -
Question:
Why does tuberculosis still remain the world's most infectious killer after
COVID?
Answer:
Introduction to TB - Tuberculosis (TB), once called consumption, is a highly
infectious disease that primarily affects the lungs. It’s an ancient disease and
proliferated in the middle ages. Currently, it’s the second main infectious cause of
death, after COVID-19. According to WHO, 1.5 million people died from the
disease in 2020. TB is most common in developing countries but TB is usually
curable and preventable under the right conditions. The neo Latin word
Tuberculosis is formed of two words – Tubercule (meaning round nodule or
swelling) and Osis (meaning condition). The main causative pathogen is
mycobacterium tuberculosis in humans and mycobacterium bovis in animals.
About the pathogen - The mycobacteria are an interesting bunch. They’re a genus
of Actinobacteria, slender, rod shaped and need oxygen to survive, that is, they’re
strict aerobes. They live and thrive at moderate temperatures and have a slow
generation time. They have an unusually waxy cell wall, which is due to
production of mycolic acid. Because of this waxy cell wall, they’re rigid, allowing
them to resist mild disinfectants and survive on dry surfaces for a long period of
time.
Symptoms - The most common symptoms of TB include chills, fever, unexplained
fatigue, night sweats, appetite loss and weight loss. TB in the lungs usually gives
rise to persistent mild to severe cough, chest pain and blood in sputum. Along with
general symptoms, TB that spreads to other organs can also cause blood in urine
and loss of kidney function, if TB affects the kidneys; back pain and stiffness,
muscle spasms, and spinal irregularity if TB affects the spine and the lymphatic
system; nausea and vomiting, confusion, and loss of consciousness, if TB spreads
to the brain.
Existing Treatments - Active, drug-susceptible TB disease is treated with a
standard 6-month course of 4 antimicrobial drugs that are provided with
information and support to the patient. Without such support, treatment adherence
is more difficult. Since 2000, an estimated 66 million lives were saved through TB
diagnosis and treatment. Doctors prescribe multiple antibiotics like isoniazid,
ethambutol and rifampin because some TB strains are resistant to certain drug
types.
Challenges faced –
The multiple drug resistant strains of TB make it harder to treat. Also, the
existing medications come with side effects on liver health.
Bacille Calmette Guerin, a vaccine administered to infants only provides
substantial immunity against TB.
Cases of latent TB are hard to diagnose, and even if they’re diagnosed,
traditional treatment takes up to 9 months.
People living with HIV are 18 times more likely to develop active TB
disease than people without HIV. HIV and TB form a lethal combination,
each speeding the other's progress. In 2020, about 215,000 people died of
HIV-associated TB.
What needs to be done - Even though cases of TB, especially the multi drug
resistant type have decreased, there still remains the need for faster acting
antibiotics, effective vaccines and better diagnosis and tracking.
Epidemiology of TB
Developing countries like the Indian subcontinent and parts of Africa have most TB patients in
the world. In 2020, an estimated 10 million people fell ill with tuberculosis (TB) worldwide. 5.6
million Men, 3.3 million women and 1.1 million children. TB is present in all countries and age
groups. 1.5 million People died from TB in 2020, making the second largest infectious killer
after COVID-19. Though almost one third of the world is infected with mycobacterium
tuberculosis, two third of the infections don’t result in symptoms, thus these cases are never
reported and tracked. Around 10% of TB infections are in children.
Incidence of TB in
India
Before COVID-19 became a
global pandemic, India was
dealing with another, much
older epidemic—TB—which
affected 2.64 million Indians
in 2019 and killed nearly
450,000 people in the country.
That is over 1000 TB deaths
every single day, well before
COVID-19 entered the
picture. In fact, no country has
a higher TB burden than India,
which accounts for a quarter
of the 10 million global TB
cases and 1.4 million TB
deaths each year.
Improving much?
Cases of latent TB are hard to
diagnose, and even if they’re
diagnosed, traditional
treatment takes up to 9
months. People living with
HIV are 18 times more likely
to develop active TB disease
than people without HIV. HIV
and TB form a lethal
combination, each speeding
the other's progress. In 2020,
about 215,000 people died of
HIV-associated TB. Since
2000, an estimated 66 million
lives were saved through TB
diagnosis and treatment.
Doctors prescribe multiple
antibiotics like isoniazid,
ethambutol and rifampin
because some TB strains are
resistant to certain drug types.
