Subclinical Tuberculosis: Addressing the Hidden Threat to Tuberculosis Control and Disease Prevention
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Abstract
Subclinical tuberculosis (Subclinical TB) remains a significant yet frequently underdiagnosed contributor to the global TB burden. Due to its lack of noticeable symptoms and its potential for spreading pathogens, many subclinical TB patients face diagnostic delays and act as silent sources of infection. Consequently, subclinical TB is just as impactful as active TB in contributing to both individual health deterioration and the spread of TB within communities. Early identification and treatment of subclinical TB cases is essential for effective TB control and must be prioritized to make substantial progress toward TB elimination, especially in high-burden countries like Thailand. In addition to passive diagnostic systems, it is recommended that active case-finding strategies be proactively implemented within the population. These strategies would facilitate early diagnosis and prompt treatment, supporting secondary prevention by minimizing further damage to the patient’s health. Furthermore, they would contribute to primary prevention by halting the spread of TB, ultimately reducing both the incidence and overall burden of the disease. This paper explores the classification, prevalence, diagnostic challenges, and clinical significance of subclinical TB, underscoring the need for proactive screening strategies to reduce the TB burden and help achieve elimination goals, both globally and in Thailand
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