World Tuberculosis Day - 2022

Each year, on the 24th of March, we commemorate World Tuberculosis Day, as an opportunity to inform the world population of the deadly disease Tuberculosis and educate and strengthen them to prevent and eradicate the diseases from the world. Every year, a theme associates this crucial health event depending on the world priorities on this infection which has sprouted among the world. For the year 2022, the world continues its mission against TB with the theme “Invest to End TB” focusing on raising funds to be utilized against the hazardous impacts caused by Tuberculosis for the current society.

Tuberculosis is a deadly disease that is caused due to the bacterium Mycobacterium tuberculosis mainly affects lungs and causes hazardous infections towards humans and animals. According to scientific evidence, temperature and wind speed increase the spread of the bacterium.

History of TB

First, in world history, lower mammals and etiologic animals got infected by an endemic resulted by a  bacterium that caused severe lung infection and the impact of that bacterium existed hidden from the human eye till the beginning of the next stages of human civilization. Gradually, people distanced from hunting animals and tended to make permanent accommodations of their own. With the rapid development of agriculture, people tend to live in large communities with each other, maintaining close relationships. With the beginning of Industrialization In the 18th century, social relations grew wider and more complex and paved a way to transform this endemic into an epidemic by a few decades of time. Tuberculosis spread apart from Europe colonies and empire – buildings to the whole world forming the fear of a deadly disease all around the world making Europe and US as breeding points. In 1834, Johann Schonlein named the deadly disease “Tuberculosis”, though no one was aware of the host of the infection.

While one out of seven people die daily due to the deadly infection, scientists all around the world conducted experiments to reveal the hidden host of this deadly disease. As a result in 1882, Dr. Robert Koch was able to reveal the bacterium which causes TB and named it Mycobacterium tuberculosis. Through further investigations and experiments on bacterium which cause TB, Koch revealed that some members of the human population show resistance to the bacterium. This natural resistance reflected a kind of control of the intracellular growth of the bacterium. In 1890, Dr. Robert Koch was able to invent TB Skin Test, using “ Tuberculin” a fluid, which can reveal the TB bacterium through measuring one’s immune response and Clemens von Pirquet and American Florence Seibert Ph.D. developed TB Skin Test and TB Blood Test to reveal the bacterium.

How the Bacterium spreads

The spread of TB occurs from infectious particles which can be spread by a carrier of infection, a human or an animal. When infectious particles are expelled from a source; nasal or oral paths are inhaled by an individual. TB usually affects the carrier’s lungs but it can affect other parts of the body, such as the brain, kidneys, or spine and affect the ongoing processes of organs. Wing Speed and Temperature are the major factors that affect the transmissibility of the bacterium. Thus indoor air pollution, tobacco smoke, malnutrition, overcrowded living conditions, and excessive alcohol use could stimulate the spread further.

Classification of Tuberculosis 

  • Pulmonary tuberculosis (PTB) – Any bacteriologically confirmed or clinically diagnosed case of TB involving the lung parenchyma or the tracheobronchial tree with or without the involvement of any other organs in the body.
  • Extrapulmonary tuberculosis (EPTB) – Any bacteriologically confirmed or clinically diagnosed case of TB involving organs other than the lung parenchyma or tracheobronchial tree, e.g. pleura, lymph nodes, abdomen, genitourinary tract, skin, bones and joints, meninges.

Recent Status of Tuberculosis in Sri Lanka

According to the estimations of WHO (Global Report 2018) Sri Lanka, with a population of 21 million, is considered a relatively low burden TB country with an estimated TB incidence of all forms of TB of 64/100,000 population, an estimated MDR TB incidence of 0.42/100,000, an estimated incidence of HIV/TB of 0.23/100,000 and TB mortality, excluding TB-HIV, of 3.2/100,000 population. The actual reported TB incidence was 47/100,000 in 2017 leading to an overall gap in case notification of about 3000 to 4000. In 2018, Sri Lanka notified 8856 patients (up from 8511 the previous year) of all forms of TB of which 4181 (47%) were bacteriologically confirmed, 2431 (27%) were EPTB, and 591 (6.7%) were retreatment cases. The majority of cases occur in the Western province (40%), with most reported from Colombo (25%). It is also observed that children contribute to 3% of the notification rate.

During the first quarter (January – March) (Q1) in the year 2019 and 2020, the total number of 2153 and 2043 cases were reported in Sri Lanka, respectively. A 5.1% decline in the total number of TB cases in the year 2020 was reported in comparison to the previous year. A decline in the number of TB cases was observed in 15 out of 25 districts. The Western province in Sri Lanka, which consists of Colombo, Gampaha and Kalutara annually reports 40% of total TB cases in the country. However, during the first quarter in the year 2020, there is a decline in the number of total TB cases in the Gampaha district, while an increase in cases in the Kalutara district was observed. 

Colombo district TB incidence remains the same. A 28.8% decline in the total number of TB cases in 2020 in comparison to the previous year was reported. The Second-quarter of the year 2020, reported a decline in the total number of TB cases in 25 out of 26 districts. Districts in the eastern part of Sri Lanka, including Batticaloa and Ampara and Polonnaruwa districts, reported nearly a fifty percent decrease in the total number of TB cases. Western Province including Colombo, Kalutara and Gampaha districts reported a decrease in one-fourth of TB cases in comparison to the second quarter in 2019. 

In addition, the percentage of loss to follow-up TB cases in comparison to the number of interrupters identified were 1.4% and 0.8% during the first and second quarters of the year 2020 respectively. There is a reduction in the number of deaths due to TB in 2020, in comparison to 2019.

Extracted from: https://www.epid.gov.lk/web/images/pdf/wer/2020/vol_47_no_50-english.pdf

Our work to prevent Tuberculosis in Sri Lanka

We , FECT have analyzed and mapped data on Tuberculosis during 2013 – 2017 and exploited the analyzed results to convey the dispersion of TB cases island-wide. Following are the 

  • Overall – The highest average is for Colombo followed by Gampaha district throughout the four quarters while lowest is shown in Kilinochchi, Mannar, Mullaitivu respectively.
  • The Third Quarter shows high averages compared to other quarters.
  • Lowest averages are shown in the second quarter.

Impacts of Climate and Pollution on Tuberculosis

As per the data compiled by our observations of case studies on the current status of Tuberculosis in Sri Lanka, we detected the impacts of climate and pollution on Tuberculosis. Here is an in-depth inquiry on the transmission of TB in Sri Lanka.

TB transmission in Sri Lanka is mostly affected by seasonal changes. Seasons suggest one’s workload and the Wind speed and rainfall depend on temperature and precipitation in the atmosphere and amount of time locals spent indoors, and thus results in the transmissibility of the bacterium, Mycobacterium tuberculosis from one to another. Air gets polluted through the untreated, active form of tuberculosis coughs, speaks, sneezes, spits, laughs or signs of an infected person can cause the spread of the bacterium as microdroplets to the air which can be spread from one infected person to the other. 

Management and Control of Tuberculosis 

National Programme for Tuberculosis Control & Chest Diseases (NPTCCD) is the central organization of the Ministry of Health responsible for controlling and preventing tuberculosis (TB) and other respiratory diseases throughout Sri Lanka. NPTCCD functions through a network of chest clinics, laboratories, chest wards and hospitals. With a moderate burden of TB and rising number of cases of respiratory diseases, TB and respiratory diseases remain as a serious public health concern. 

When considering the preventive measures that can be taken against Tuberculosis, providing good ventilation appears at the top. When ventilation is less, the ability for the bacterium to exist in the air gets high. Natural lights such as UV (Ultraviolet) kill the adverse bacteria which cause various health impacts. Maintaining good hygiene also prevents TB. Habits such as covering the mouth and nose when sneezing or coughing can be introduced as examples.