Tuberculosis, An Old and Highly Infectious Disease That Still Needs Attention in COVID-19 Pandemic

Tuberculosis (TB) is an old disease. Studies of human skeletons show that it has affected humans for thousands of years. TB is a communicable disease that is a major cause of ill health and one of the leading causes of death worldwide. Until the coronavirus (COVID-19) pandemic, TB was the leading cause of death from a single infectious agent, ranking above HIV/AIDS. Today, nearly 28,000 people worldwide become infected with TB every day, and more than 4,100 people die from the disease.

In terms of numbers, TB is far more likely to cause illness and death than COVID-19, but why it seems remained out of the public attention? 

The first reason is that the novel coronavirus is a new virus suddenly happened that is constantly mutating and has kinds of uncertain factors. And tuberculosis, although highly infectious, but has affected human for thousands of years and become preventable and curable now. For another reason is that still many people do not know the existence of TB disease compared to COVID-19.

Common symptoms of tuberculosis

TB is caused by the bacillus Mycobacterium tuberculosis, which is spread when people who are sick with TB expel bacteria into the air (e.g. by coughing). The disease typically affects the lungs (pulmonary TB) but can affect other sites.

1. Cough, expectoration, hemoptysis

Cough is a common symptom of tuberculosis, inchoate cough is lighter, it is usually dry cough or have a few sticky phlegm, and can develop to cough aggravates, phlegm increases, purulent phlegm, phlegm with blood and even massive hemoptysis when seriously.

2. Chest pain

Chest pain is also one of the common local symptoms of tuberculosis, sometimes dull pain, some tingling sensation from chest may worsen with breathing or coughing.

3. Low fever

Tuberculosis fever is very characteristic, some people may have long-term low fever, temperature increased to 37.4℃~38℃, generally in the afternoon or evening is more obvious, and subside in early morning or the next day, usually lasting more than 2 weeks. However, a high fever can occur when the disease worsens.

But there are also a small number of TB patients are asymptomatic or mild symptoms. Most of these patients are found through physical examination, so it is recommended that we must pay attention to chest X-ray examination during physical examination, which is a very important means to find early tuberculosis. 

Transmission of tuberculosis

According to statistics, an untreated TB patient can infect 10~15 people within a year, and the infected person has a 10% chance of developing the disease in his or her lifetime.

1. Air-respiratory transmission

Patients speak loudly, cough, sneeze, discharge droplets with tuberculosis bacilli suspended in the air, others if inhaled droplets with bacteria can cause disease.  Tuberculosis bacillus in dry phlegm is inhaled by healthy person along with dust can also cause infection.

2. Digestive tract transmission

If cows suffer from mammary tuberculosis, direct drinking of unsterilized raw milk, tuberculosis bacilli can cause infection and morbidity in various parts of the digestive tract.

Prevention and treatment of tuberculosis

1. Diagnosis

Early detection and rapid control of disease are the most important measures for tuberculosis prevention and treatment at present. People that has tuberculosis symptom should see a doctor in time and take necessary auxiliary examination such as X-ray, M. tuberculosis detection and sputum smear testing. Once diagnosed, scientifically targeted treatment is needed.

2. Prevention

Take appropriate measures to prevent infection, such as keeping a distance from patients, reducing close contact, wearing masks, and frequent ventilation.

3. Treatment

About 85% of people who develop TB disease can be successfully treated with a 6-month drug regimen and regimens of 1–6 months can be used to treat TB infection.
It is important to emphasize that TB patients must take their medicine regularly and complete the whole process. The treatment course of TB should be at least 6 months, during this period cannot be stopped privately, otherwise it is easy to lead to drug-resistant tuberculosis. Drug-resistant TB not only takes longer and costs more to treat, but also has a much lower cure rate than ordinary TB.