Cough and the Transmission of Tuberculosis

Abstract

Cough is a predominant feature of respiratory infection and, in tuberculosis, is of prime importance for transmitting infection. Tuberculosis is transmitted by the air, yet the process by which bacilli are aerosolized has received little attention. Features of cough may account for differences in transmission rates from source cases of pulmonary disease. We review the literature on the mechanisms and characteristics of cough in tuberculosis in the context of the dissemination of infection. Coughing is probably more important than other respiratory maneuvers, and characteristics of mucus may have an important role but data are scarce. Direct mechanisms of cough in tuberculosis are unknown, as are temporal and other patterns that correlate with the release of viable airborne bacilli. Other than antituberculous chemotherapy and masks, there are few methods of modulating cough in tuberculosis. This is an increasingly important area for research.

Duration of Pulmonary Tuberculosis Infectiousness under Adequate Therapy, as Assessed Using Induced Sputum Samples

“…Among these, cough is regarded as the predominant factor affecting PTB transmission and may be gradually decreased by chemotherapy3334. However, the direct measurement of the human-to-human transmission of PTB is complex and difficult35. Moreover, convincing data on the effectiveness of masks and cough hygiene in reducing PTB transmission are few, although they are widely used protection measures35.…”

Mechanisms of Mycobacterial Transmission: How does Mycobacterium Tuberculosis enter and Escape from the Human Host

“…Although cough is a well-known hallmark feature of active pulmonary tuberculosis, very little is known about the pathogenesis of infectious cough [17]. Cough may be a natural consequence of lung inflammation and host production of prostaglandins, bradykinin and other inflammatory mediators that activate afferent neuronal C-fibers in the lung mucosa [18].…”

Early diagnosis and effective treatment regimens are the keys to tackle antimicrobial resistance in tuberculosis (TB): A report from Euroscicon's international TB Summit 2016

“…13,14 Several studies studying cough patterns and household transmission have shown that patients cough more during the day than at night and that cough frequency is an important predictor of transmission. 15,16 As noted by Richard Turner (NHS Foundation Trust, UK), the act of coughing in the context of infectiousness of TB has not been looked into. The cause of cough in a TB patient; its necessity for the transmission of TB, correlation with infective/non-infective strains of the pathogen and characteristics of the optimum cough droplet for disease transmission are yet to be completely understood.…”