Lecture 27: Tuberculosis Flashcards
what is pulmonary tuberculosis?
An infectious disease caused by Mycobacterium Tuberculosis, commonly in the lungs
It is an airborne disease spread by droplets and coughing/sneezing etc
what diagnosis options are there for TB?
- Sputum smear microscopy
- Culture myobacterium tuberculosis
- chest x-ray
- GeneXpert MTB/RIF
what treatments options are there for TB?
- standard treatment: 6 months combination treatment with rifampicin, ethambutol, pyrazinamine and levofloxacin
- drug resistant TB: minimum og 9-11 month combination treatment
- DOTs (directly observed therapy) - people need to complete 6 months treatment and have someone supervise it.
how does mycobacterium tuberculosis in humans work?
what is the progression of pulmonary tuberculosis?
- Latent TB (no symptoms) affects 1.7 billion people and 5-10% of these will become TB disease.
what preventions exist for TB?
Primary prevention: Bacillus Calmette-Guerin (BCG) vaccine. Commonly given to children in high TB-prevalence countries (so not in NZ).
- but it has incomplete protection. only lasts up to ~20 years
There is also prevention treatment to stop the progression from Latent TB to TB disease but this is only given to high-risk groups
who is most at risk of Pulmonary TB disease?
- Close contacts who are living or working with (e.g. overcrowding or workers in factories)
- Children aged <5 years
- Those with HIV
- Co-morbidities e.g. diabetes
- people in low socio-economic groups
- poor housing, nutrition, education and poverty
- smoking and alcohol
what are the symptoms of TB?
- chronic cough
- fever
- anorexia
- hemoplysis (coughing blood)
- night sweat
- fatigue
- weight loss
- chest pain
what is the descriptive epidemiology of global TB?
WHO Global TB Report 2021
- 5.8 million newly diagnosed with TB in 2020
- 1.3 million TB deaths
- 206,030 people with multi-drug resistant (MDR) TB were detected and notified
- 23% of world’s population is estimated to have latent TB infection
who does TB affect most in the world?
8 countries account for 2/3 of the new cases
- India (26%)
- Indonesia (8.5%)
- China (8.4%)
- Philippines (6%)
- Pakistan (5.7%)
- Nigeria (4.4%)
- Bangladesh (3.6%)
- South Africa (3.6%)
how does TB relate to the top causes of death worldwide?
2019 data shows that TB is among the top causes of death world-wide
what is the data for TB notifications in New Zealand?
TB notifications in New Zealand by year and ethnicity data
Small numbers of TB in NZ.
TB is a notifiable disease in NZ
there is ~300 per year which is been stable from 2013-2020 and the highest rates are in asian ethnicities
what are the goals for TB?
what is the sustainable development goal for TB?
By 2030, end epidemics of AIDS, tuberculosis, malaria and neglected tropical diseases and combat hepatitis, water-borne diseases and other commincable diseases
What are the global trends of TB incident cases and incidence rate
Global trends in the estimated number of incident TB cases (left) and the incidence rate (right) 2000-2020
All TB cases have slightly gone down over this period of time. more of a decrease in HIV-positive TB cases, likely because HIV rates are dropping too
what are the determinants of health for TB?
same as for everything lol.
Children more vulnerable, working age more vulnerable, men more than women, smoking, alcohol - All of these impact TB
what is TB like over the years in England and Wales
deaths rates have been decreasingly going down since 1838
rates began declining since before treatment and vaccination came
so this is a sign that it could be going down due to improved housing and health care etc
what are the key challenges to TB control and elimination from a health perspective?
- the need for better/cheaper diagnostic tests
- gaps in understanding of basic biology of TB
- a new vaccine
- poor health systems
- increasing drug resistance
what is the TB situation like in indonesia?
Indonesia has a population of ~250 million people
They have a TB research centre - faculty of medicine, universitas padjadjaran (UNPAD)
the TB prevalence is 647 per 100,000 population
second highest TB burden country
why is the need for better/cheaper diagnostics test a challenge?
Sputum smear microscopy tests need labs
culture mycobacterium tuberculosis take longer
chest xrays is hard to get into communities
GeneXpert MTB/RIF is expensive and hard to get into communities
There is a need for cheap, easy, rapud and reliable test (e.g. point-of-care test) with no requirement for electricity, specialised laboratory and can be easily performed in the field. Need to consider access for people who can’t get to health care
How can we better understand the basic biology of TB?
The INFECT Study
- Innate Factors in Early Clearance of M. tuberculosis
*look at lecture to understand it, its a lot to make into a flashcard*
they probably won’t ask about it anyway
what has been found about a new vaccine?
the existing vaccine (BCG vaccine) is not very effective. revaccination might be needed?
what are the problems with the health systems?
indonesia has accessible cummonity health clinics. some have labs, some have xrays and they are free
private practionera strengthen the public-private partnership for TB case detection
approx 50% of people in low and middle income countries seek care from a private practitioner first. But the practitioner is busy, often works in more than one location but doesn’t want to lose patients. By accessing private care first, patients may recieve sub-optimal care and there is no reporting to the national TB programme. patients find private care more convenient because there is less waiting time and they trust it more.
for some reason i feel like this lecture won’t have too many questions about it….
