Raising Awareness : How much do you know about TB?Aug 11, 2016
Svetlana Tomasova, UNDP Laboratory Specialist
UNDP: Tuberculosis (TB) is something to be afraid of. Tell us, why is this disease so dangerous for a person? What are the consequences of TB?
Ms Tomasova: Tuberculosis is known to people since ancient times. This disease was widespread throughout the world and was one of the main causes of high mortality of the population.
The first step in transmission of infection in the transmission chain of tuberculosis is from a bacillary patient to a healthy person through close contact. At this stage, transmission of infection can be prevented by early detection and effective treatment of bacillary patients, and effective sanitary-epidemic measures preventing the spread of infection.
However, the disease does not develop in all infected with tuberculosis. A person infected with tuberculosis Mycobacterium, has the so-called latent tuberculosis. However, only about 10% of those infected actually get ill, of which 5% - in the first 2 years after infection, and the other 5% - in the course of the rest of their lives.
Factors that increase the likelihood of developing the disease, include time elapsed from the time of infection and the immune status of the infected, including HIV infection. Other disease risk factors include: age, gender, malnutrition, co-morbidities (diabetes, etc.). Prognosis depends on the stage of the disease localization, drug resistance, and timeliness of the start of treatment, however, is generally considered conditionally unfavorable. The disease, without nourishing diet, favorable social and hygienic conditions, climate supported treatment, responds poorly to chemotherapy, especially multidrug-resistant and extensive drug-resistant tuberculosis. Ability to work in many cases is fully lost, and even if there is no disability after treatment, there still is a ban on employment of such persons in a variety of decreed professions. Timely treatment allows for full rehabilitation, but does not guarantee the impossibility of disease recurrence. Late diagnosis or careless treatment of the patient leads to disability which often ends up leading to patient's death.
UNDP: Is TB transmitted via droplets, from mother to child, through a touch? How does one catch TB?
Ms. Tomasova: Through numerous experiments we have studied pathways of mycobacterium into the human body. The input gate of TB infection is the respiratory tract, i.e., the main way of spread of the disease is airborne, or as it is now customary to say - aerosol. But there is a danger of enteral infection (via the gastrointestinal tract) as well as through broken skin and mucous membranes, which implies the need for hygiene environment.
The primary localization of infectious nidus plays a significant role. There are the following ways of transmission of tuberculosis:
· Airborne. Tuberculosis mycobacterium enters the air with droplets during coughing, talking and sneezing of patients with active tuberculosis. When inhaled, these droplets with mycobacterium enter into the lungs of a healthy person. This is the most common route of infection.
· Alimentary. Infiltration occurs through the digestive tract.
· Contact. Cases of infection through the conjunctiva of young children and adults. It is sometimes accompanied by acute conjunctivitis and inflammation of the lacrimal sac. TB Infection through skin is rare.
· Intrauterine infection with tuberculosis. Infection occurs in either through contagion by tuberculosis of placenta, or by infection of damaged placenta during birth for mother sick with tuberculosis. This way of transmission of tuberculosis infection is extremely rare.
The resulting aerosol particles are of different sizes. The largest settle quickly. 5 micron particle size, containing the infectious agent, can be kept in suspension for several hours. When inhaled, they penetrate into the deeper regions of the lungs through the small bronchi, and contain within mycobacterium may, infiltrating the lung tissue, form the primary nidus of the disease.
One bacillary patient can infect about 10 people per year. Given an average duration of such patient's life, in the absence of treatment for two years, he/she infects up to 20 people or more. The risk of infection depends on:
· massiveness of bacterioexcretion within patient;
· the time of contact with the patient;
· close contact and size of the premise in which contact occurs with bacillary patients.
UNDP: Is TB accompanied by any other diseases?
Ms. Tomasova: Secondary factors of risk of tuberculosis include chronic diseases such as diabetes, peptic ulcer and 12-duodenal ulcer, chronic bronchitis, mental illness, alcoholism, drug addiction.
TB infection affects not only the respiratory system but also the bone tissue, skin, eyes, and internal organs. Tuberculosis and its consequences often cause long-term disability and temporary disability.
UNDP: What are the modern practices of detecting and diagnosing TB?
Ms. Tomasova: Active tuberculosis is detected by microscopic examination of a sputum smear. However, negative smear does not mean the absence of disease. Tuberculosis at a very early stage, as well as tuberculosis in children, often gives negative result in the stroke analysis. X-ray and fluoroscopy allows a sufficiently high reliability to identify tuberculosis, especially in the later stages, when it began to unravel the lungs of the patient. The presence of the obvious collapse of the lung with a negative smear result indicates poor-quality analysis of sputum. Sputum culture (cultural studies) is the cultivation of mycobacterium culture in a specially equipped laboratory sample of the patient's sputum.
Under laboratory conditions, the Koch bacillus multiplies slowly, but the advent of the automated system BACTECMJIT 960, reduced the time of testing from three months to 28 days. Conducting this research is very important for the following reason. Grown culture of mycobacteria, separated into several samples, allows determining its sensitivity to various antibiotics. This is the only way to determine which types of antibiotics the Koch bacillus is sensitive to, and which it resists. No smear or X-rays can provide such information. On the basis of drug resistance test results of Mycobacterium grown culture the doctor can choose the right combination of drugs. Currently, the molecular-genetic diagnostic methods that allows to detect the presence of mycobacteria in a biological material of a patient, as well as to test for anti-TB drugs of first and second row, is developing fast. These rapid tests include HAIN-test and GeneXpert / MBTRif, which has reduced the time of diagnosis in the case of HAIN-test to 48 hours, and GeneXpert / MBTRif to 2 hours.
UNDP: What is a "closed" form of TB?
Ms. Tomasova: There are open and closed forms of tuberculosis. In an open form the sputum or other natural secretions of the patient show presence of tuberculosis Mycobacterium. Open forms also include those types of respiratory tuberculosis in which, even in the absence of bacterial detection, there are clear signs of contacts of nidus with the environment: a cavity (decay) in the lung, tuberculosis of the upper respiratory tract. If the patient does not comply with hygiene precautions, he can be contagious to others. In a "closed" form, tuberculosis Mycobacterium are not found in sputum with available methods, patients with such epidemiological form are not hazardous or are of low-hazard to others.
UNDP: What is MDR-TB?
Ms. Tomasova: Bacteria that cause tuberculosis (TB) can develop resistance to antimicrobial drugs used to treat the disease. Multidrug-resistant TB (MDR-TB) - means that TB that does not respond to at least isoniazid and riphampicin, the two most powerful anti-TB drugs.
The main reason for development of multi-drug resistance is improper management of TB. Most TB incidents are curable subject to strict compliance with the six-month course of drug therapy for patients, accompanied with the support and supervision. Improper use of antimicrobials or inefficient use of dosage forms, as well as the premature discontinuation of treatment, may lead to the development of drug resistance.
To combat drug-resistant TB it is necessary to:
· properly finalize primary treatment of patients with TB;
· ensure adequate infection control in health facilities;
· Ensure proper use of recommended second-line drugs.
UNDP: How long is TB treated for?
Treatment of tuberculosis is a long process, which takes six months in the case of normal (sensitive) TB up to two years in case of drug-resistant TB. Treatment must be continuous. Koch's bacillus should not be able to recover from the "bombardment” of strong artillery of anti-TB drugs until its complete elimination. Treatment must be carried out simultaneously with the use of several anti-TB drugs. Each of the medications that the patient takes on daily basis has different mechanism of effect, i.e., each of them affects various aspects and manifestations of life of the Koch's bacillus, and only when taken together they can achieve the goal of destroying the infection. Under no circumstances should a patient be treated with an incomplete set of drugs, prematurely terminate the treatment or temporarily interrupt the started treatment or take pills irregularly.
UNDP: Why is there a social stigma around the disease?
Ms. Tomasova: The Greek word "stigma" ("label", "stamp", "mark"), derived from the ancient custom branding of slaves and criminals, in today's realities is used in the sense of negative human association with something shameful, revolting. Today, being under stigma is associated with an extremely strong social label, which completely changes the attitude towards a certain category of people, forcing them to be considered solely as people of undesirable quality.
To avoid becoming a victim of the stigma often infected people are forced to hide their diagnosis, and stop all treatment. Thus, stigma is an essential barrier in combating the spread of these diseases and implementation of relevant programs. Low level of awareness, prevalence of simplified information and misconceptions about transmission and clinical manifestations of the disease led to the fact that the disease turned into a stain.
Unlike those infected with other serious diseases, people living with tuberculosis, as a rule, do not find the sympathy and compassion of the society. Moreover, this status makes the patient a target for all sorts of violations of his/her rights. Often healthy people perceive infected as a threat to personal safety, treating them with hostility and trying to dissociate themselves from them in various ways, up to overt discrimination and even exclusion.
In case of tuberculosis, entering of the pathogen of the disease - the Koch bacillus - into the body does not necessarily lead to the development of the disease because the immune system in most of the times is able to cope with the infection. Risk of falling ill in the first place is highest for people leading unhealthy lifestyles, with a weakened immune system. Thus, more than half of the infected people have Tuberculosis as a secondary disease. The immune system of a healthy person simply blocks the dangerous bacteria. The risk of the transmission of extra-pulmonary TB is virtually absent. The vast majority of cases are successfully being treated with proper medication, which is free of charge. During the intensive phase of treatment, which lasts two months, the patient becomes totally non-contagious, and all the symptoms of the disease disappear.
The continuing high level of stigma against TB patients also shows insufficient awareness about this disease.
UNDP: What methods of identification, diagnosis and fight with TB exist in Turkmenistan?
Ms. Tomasova: The main objective of anti-TB program is reduction of the number of incidence of tuberculosis infection. To do this, anti-TB program activities should ensure that:
· each person discharging bacteria is promptly identified and referred for treatment;
· every non-bacillary TB patient must also be identified and referred for treatment, while he is not contagious;
· uninfected persons should not become infected.
Official strategy for TB control in Turkmenistan is DOTS (short-course chemotherapy under direct observation), - the name given to the WHO strategy for TB control. After its introduction in 1999, which was supported by the WHO, by 2007 DOTS coverage has reached 100% in the civil sector. Since 2010, within the framework of the Global Fund "Purposeful strengthening and expanding of qualified services on TB diagnosis and treatment in Turkmenistan", the country has been rapidly developing laboratory diagnostics of tuberculosis.
In Ashgabat and in all provinces medical facilities have been equipped with modern apparatus GeneXpert / MBTR, which can detect tuberculosis Mycobacterium, and resistance to riphampizin is defined in two hours. The country is widely implementing and using molecular genetics techniques to identify TB - HAIN-test, culture studies on solid and liquid media in the automated BACTEC MJIT 960 system, i.e. the country has the most modern technology for diagnosis of tuberculosis. The project has purchased anti-TB drugs for first and second-line treatment of patients.
UNDP: What methods are the most effective in the prevention and control of TB?
Ms. Tomasova: Medical and social assistance with preventive orientation in tuberculosis involves: BCG vaccination and revaccination against tuberculosis, which protects against the development of the disease by an average of 85%; preventive medical treatment of contacted people (relatives of the patient); early detection of the disease and clinical examination of patients; dispensary observation of the patient's relatives. Particular importance in the prevention of tuberculosis is given to measures in limiting contact of patients with healthy people.
Individual prevention of tuberculosis involves, first of all, promotion of a healthy lifestyle, absence of bad habits, good nutrition, personal hygiene, high medical activity (seeking medical care in a timely fashion, medical examination, adequate treatment of cold-related diseases, diabetes, peptic ulcer gastric and 12-duodenal ulcer, chronic nonspecific lung diseases, regular lung fluorography inspection, etc.).Contact information
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