How it is transmitted and who is really at risk
The mycobacterium becomes airborne when a person with active pulmonary tuberculosis coughs, sneezes, talks or sings loudly. The smallest drops remain suspended for a long time, especially in a closed, unventilated room. That is why it is not social status or household cleanliness that is decisive, but the duration and proximity of contact, as well as ventilation. Tuberculosis is not transmitted through a handshake, dishes, clothing, bed linen, food or kisses - mycobacterium only enters the respiratory tract.
In this case, one breath is usually not enough. Infection is a matter of the concentration of the pathogen in the air and the time spent nearby: a short meeting on the street is practically safe, but weeks in one unventilated room is a completely different matter. That is why family members and those who work side by side with the sick person are examined first. And for the same reason, ordinary ventilation and sunlight remain simple but truly effective protective measures: in the open air and under ultraviolet light, mycobacteria quickly loses its viability.
- Prolonged close contact with a person with active disease is the most significant factor
- Diabetes mellitus - the risk of getting sick is several times higher, and the course is more severe
- HIV infection is the most powerful known risk factor for the progression of infection to disease
- Smoking and chronic lung diseases
- Inadequate nutrition, underweight, heavy physical labor without recovery
- Taking drugs that suppress the immune system, treatment with hormones, condition after transplantation
- Chronic stress, lack of sleep, serious illnesses
- Working and staying in crowded places with poor ventilation
Infection and disease are different things
A huge part of the world's population has encountered mycobacteria at least once. For most, the immune system copes with and “immurs” the pathogen: it remains in the body in an inactive state, does not multiply, does not cause symptoms and is not contagious to others. This condition is called latent tuberculosis infection. Only a small proportion of those infected become ill during their lifetime, and usually when the body's defenses are weakened.
- Latent infection: no complaints, normal lung scan, clean sputum, person is not contagious
- Active tuberculosis: there are symptoms or changes in the image, the pathogen multiplies, if the lungs are affected, the person can be a source of infection
- A positive Mantoux test or blood test indicates an infection, but does not in itself mean illness
- The risk of a latent infection turning into a disease increases sharply with HIV, diabetes, treatment with immunosuppressants, and after major operations.
- If the risk is high, the doctor may prescribe preventive treatment for a latent infection - a short course that reduces the likelihood of getting sick
First signs: why two weeks is a milestone
Tuberculosis rarely begins acutely. Usually everything looks like a prolonged cold or “smoker’s bronchitis”: a person coughs, sweats a little at night, and gets tired faster. The temperature is kept low, so it is not taken seriously. Weeks and months pass, but there is always an explanation - weather, work, allergies. That is why a simple screening rule has been adopted all over the world: a cough lasting more than two to three weeks requires examination for tuberculosis, even if the person feels generally fine.
- Cough lasting longer than two to three weeks - dry at first, then with sputum
- Weakness and fatigue, decreased performance
- Night sweats, sometimes profuse
- Low-grade fever, more often in the evening
- Decreased appetite and weight loss
- Chest pain associated with breathing
- Shortness of breath on exertion as the process progresses
- Hemoptysis is a serious, but not obligatory and not an early sign.
It is also worth remembering that tuberculosis is not only pulmonary. It can affect lymph nodes, bones and spine, kidneys, intestines, and brain membranes. Extrapulmonary forms are not airborne but are diagnosed later because they are less often thought of.
Examination: what really confirms the diagnosis
- Флюорография или рентгенография органов грудной клетки — базовый и самый доступный метод выявления. Плановое обследование раз в год существует именно для того, чтобы находить disease до появления жалоб.
- Исследование мокроты на кислотоустойчивые бактерии — микроскопия, обычно несколько образцов, включая утренний.
- Молекулярно-генетический тест мокроты — за считанные часы обнаруживает ДНК микобактерии и одновременно показывает устойчивость к ключевому препарату. Это принципиально меняет тактику с самого начала.
- Посев мокроты на питательные среды с определением чувствительности — самый точный метод, но результат ждут недели.
- Компьютерная томография органов грудной клетки — уточняет характер и распространённость изменений, когда рентген неоднозначен.
- Проба Манту, кожная проба с рекомбинантным аллергеном или анализ крови на высвобождение интерферона — показывают инфицирование, важны у детей и при подозрении на латентную инфекцию.
- Общий и биохимический анализ крови, тест на ВИЧ, глюкоза крови — оценка фона, на котором развилась болезнь.
- При необходимости — бронхоскопия с забором материала, если мокроты нет или она неинформативна.
Treatment: why the course is long and why it should not be abandoned
Mycobacterium grows extremely slowly and can wait out unfavorable conditions in a dormant state. Some of the pathogens in the outbreak hardly divide, and medications have little effect on them. This is why treatment is never short: the standard course takes at least six months and always includes several drugs at the same time - with monotherapy, resistance develops very quickly. The course is divided into an intensive phase, when the bulk of the pathogen dies, and a continuation phase, the task of which is to finish off the remaining dormant forms and prevent the disease from returning.
- Схему и длительность подбирает фтизиатр по результатам определения чувствительности возбудителя.
- Приём препаратов проходит под непосредственным наблюдением медработника — эту стратегию называют ДОТС. Смысл не в контроле «за поведением», а в том, чтобы ни одна доза не была пропущена.
- Самочувствие улучшается обычно уже через 2-4 недели: уходят температура, потливость, возвращается аппетит. Это самая опасная точка курса, потому что появляется соблазн прекратить лечение.
- Прерванное лечение приводит к тому, что выживают наиболее устойчивые микобактерии. Развивается лекарственно устойчивая форма, лечение которой длится от полутора лет, тяжелее переносится и хуже заканчивается.
- Побочные эффекты возможны, и о них нужно сообщать врачу, а не отменять препараты самостоятельно: чаще всего схему можно скорректировать.
- Эффективность оценивают повторными анализами мокроты и снимками в установленные сроки.
Safety of loved ones and life after diagnosis
- A person with active pulmonary tuberculosis, in whom the pathogen is detected in the sputum, is contagious. With extrapulmonary forms and latent infection there is no danger to others.
- With effective treatment, the number of released bacteria quickly decreases: as a rule, after two to three weeks of therapy, the patient no longer poses a significant danger to others. The exact timing is determined by the doctor based on the test results.
- In the first weeks, simple measures are important: ventilation, a separate room if possible, a mask when in contact, covering your mouth when coughing, sunlight - the mycobacterium quickly dies in the open air and in ultraviolet light.
- Everyone who lives nearby must be examined: an X-ray of the lungs, and skin tests for children. This is not a formality, but a way to find the disease at an early stage in those who do not yet feel anything.
- It is enough to wash dishes and linen in the usual way - the infection cannot be transmitted through them.
- Smoking and alcohol during treatment significantly worsen drug tolerability and outcome; Eating enough protein, on the contrary, helps recovery.
After completing the course, the person returns to normal life: work, study, family, sports. Scar changes may remain in the lungs, which are visible on photographs, do not require treatment and do not limit the ability to work. Observation by a TB specialist for a set period of time is necessary in order to notice a rare relapse in time, and not because the person remains sick forever.
And the last thing is worth saying directly. The most dangerous consequence of fear of a diagnosis is not the diagnosis itself, but procrastination. A person with a persistent cough spends months being treated for bronchitis, afraid to hear the word “tuberculosis,” and all this time continues to go to work, ride in crowded transport and hug his children. The examination takes several days and in the vast majority of cases ends in nothing. And if the diagnosis is still confirmed, the early stage is treated faster, easier and with better results than the common process after six months.
