Active or latent tuberculosis increases susceptibility to SARS-CoV-2 and the severity of COVID-19


Coronavirus infection COVID-19 (from the COrona VIrus Disease 2019) is a potentially fatal acute respiratory infection caused by severe acute respiratory syndrome 2 virus (SARS-CoV-2). Currently, the assessment of risk factors associated with COVID-19 is ongoing, which will allow more efficient distribution of health resources in patients with a high probability of severe infection complications. According to a study by Chinese scientists published March 16, one of these risk factors may be active or latent tuberculosis.

The study was conducted in February 2020 in Shenyang (China) and included 36 patients with SARS-CoV-2 infection confirmed by real-time polymerase chain reaction. The age of patients ranged from 25 to 79 years (average 47 years), the ratio of men and women - 1: 1; 42% of patients were associated with an outbreak in Wuhan (Hubei).

In 27 patients (75%) the disease was mild, the remaining 9 patients (25%) were in serious or critical condition. Infection with Mycobacterium tuberculosis (MTB) diagnosed by IGRA was identified in 13 cases, including 7 out of 9 patients with severe or very severe COVID-19. In patients with pneumonia caused by new coronavirus, MTB infection was detected more often (36%) than in patients with bacterial pneumonia (20%; p = 0.0047) or pneumonia caused by other viruses (16%; p = 0.024). In addition, MTB infection was observed more often than other concomitant diseases (36% vs diabetes - 25%, hypertension - 22%, coronary heart disease - 8.3%, chronic obstructive pulmonary disease - 5.5%). MTB coinfection was significantly associated with the severity of coronavirus infection (severe critical 78% vs mild/moderate 22%; p = 0.0049) and disease progression rate: from infection to onset of symptoms (MTB + SARS-CoV-2 : 6.5 ± 4.2 days vs SARS-CoV-2: 8.9 ± 5.2 days; p = 0.073) and from onset of symptoms to their qualification as severe (MTB + SARS-CoV-2: 3.4 ± 2.0 days vs SARS-CoV-2: 7.5 ± 0.5 days; p = 0.075).

Based on the results, the authors conclude that active or latent MTB infection increases susceptibility to SARS-CoV-2 and the severity of COVID-19. Obviously, these data need to be confirmed on a larger sample, however, given the high prevalence of latent tuberculosis (25% of the global population), routine MTB testing of patients with COVID-19 seems to be a rational recommendation.



Liu Y. et al. Active or latent tuberculosis increases susceptibility to COVID-19 and disease severity.