The tuberculosis bacteria mainly enter the body through the respiratory tract via droplets, causing pulmonary tuberculosis (accounting for 90% of tuberculosis cases). The bacteria invade the cells of the alveoli, creating bacterial reservoirs, then spread to the lymph nodes in the area and then to other tissues. Tuberculosis bacteria can also enter the body through the digestive tract, causing gastrointestinal tuberculosis.
What is tuberculosis bacteria?
The tuberculosis bacteria, also known as Mycobacterium tuberculosis, was isolated by Robert Koch in 1884 and is commonly referred to as the Koch bacillus.
This bacteria causes tuberculosis in humans, and until the first half of the 20th century, there was no effective treatment for it. Streptomycin was first introduced for tuberculosis treatment in 1946, followed by Rimifon in 1952, both of which helped to reduce the rate of tuberculosis. However, the number of tuberculosis infections is currently on the rise again.
According to the World Health Organization (WHO), tuberculosis currently infects one-third of the world’s population, with an additional 8-9 million new cases and 3 million deaths annually. In particular, HIV/AIDS has created favorable conditions for the development of tuberculosis. Tuberculosis continues to be a major global health problem. WHO has confirmed that tuberculosis is coming back and is worse with multidrug-resistant tuberculosis. In developing countries, the number of new infections per year is increasing rapidly, especially among HIV-infected individuals.
Characteristics of tuberculosis bacteria
Tuberculosis bacteria have a straight or slightly curved shape, are small, and are either isolated or clumped. This bacteria has no flagella, does not move, has no capsule, and does not produce spores. When stained with Ziehl-Neelsen stain, the bacteria appear red.
Tuberculosis bacteria divide very slowly, with only one division every 15-20 hours, while other bacterial species divide rapidly in minutes. This is a small bacterium that can tolerate weak disinfectants and can survive in a dry state for several weeks.
Tuberculosis bacteria are very sensitive to environmental factors. The optimum temperature for growth is 37 degrees Celsius. The bacteria can survive for several months in a moist and cool environment.
Possibility to cause disease in humans
Leprosy is a social disease that can easily and quickly spread in developing countries. More than 50% of AIDS patients are also infected with leprosy.
The leprosy bacillus primarily enters the body through the respiratory tract via droplets, causing pulmonary tuberculosis (accounting for 90% of all tuberculosis cases), where bacteria form nodules in lung tissue, then spread to lymph nodes and other tissues. The leprosy bacillus can also enter the body through the digestive system (often through fresh cow’s milk), causing gastrointestinal leprosy.
From the initial infected organs, the leprosy bacillus can spread throughout the body via blood or lymphatic vessels, causing secondary tuberculosis such as meningitis, peritoneal tuberculosis, bone, joint, lymph nodes, and kidneys.
Microbiological diagnosis
Direct diagnosis
Direct diagnosis is based on the patient’s specimen. Depending on the type of leprosy, the specimen can be sputum, feces, cerebrospinal fluid, or urine. If the specimen is sputum, it must be treated with chemicals to liquefy it and remove impurities. Then, the sediment is collected, stained, and examined under a microscope.
Direct staining: Make a smear from the specimen, stain with Ziehl-Neelsen to detect acid-fast bacteria. Combined with clinical signs and X-rays, this method has diagnostic value. Direct staining is mainly used to diagnose pulmonary tuberculosis.
Culture: After processing, the specimen is cultured in Sauton or Loewenstein medium, or both, for an accurate result, but it takes a long time. Therefore, diagnosis is often based on other techniques. Currently, some rapid culture media are being studied…
PCR gene amplification reaction
The PCR amplification reaction yields rapid and accurate results and is well-suited for the diagnosis of extrapulmonary tuberculosis, but can only be performed in facilities with suitable conditions. This technique is highly sensitive and specific, but comes with a high cost.
Methods of tuberculosis prevention
Tuberculosis can be prevented by specific and non-specific methods, including:
Specific prevention
The BCG vaccine, developed by the Calmette and Guerin doctors, is produced by repeatedly growing bovine tuberculosis bacteria in a medium containing cow bile, rendering the bacteria unable to cause disease while still being able to stimulate a strong immune response. The vaccine is administered to newborns as part of the expanded immunization program and to older children and adults only when the Mantoux test is negative.
Non-specific prevention
In non-specific prevention, the most important thing is to detect and cut off the source of transmission.
Efforts should be made to improve health education and communication for the public to raise awareness of disease prevention.
In healthcare facilities or places with a high risk of transmission such as tuberculosis hospitals or prisons, infection control measures should be implemented, including:
Limiting transmission within the community by ensuring that patients wear masks, cover their mouth when sneezing or coughing, and dispose of sputum properly. Objects that may be contaminated should be handled properly. Taking advantage of sunlight to limit bacterial growth and spread. Ensuring good ventilation to reduce the concentration of tuberculosis bacteria in the air.
Treatment of tuberculosis
Early treatment is essential to minimize the adverse effects on health.
The treatment method includes directly observed treatment (DOTS).
The standard treatment regimen recommended by the Ministry of Health is 2S(E)HRZ/4RH or 2S(E)HRZ/6HE.
Patients must comply with the following principles:
- Take medication according to the standard regimen recommended by the Ministry of Health.
- Take medication for the prescribed duration of time.
- Take medication on an empty stomach and at the same time every day.
Johnny Jacks was born in 1985 in Texas, USA. He is the founder of Good Health Plan and is passionate about helping people improve their health and physical well-being. With over a decade of experience working in the healthcare industry, he currently works at Goodheathplan.com – a blog that shares knowledge on beauty and health.