BACKGROUND: Latent tuberculosis infection (LTBI), defined as a state of persistent immune response to prior-acquired Mycobacterium tuberculosis antigens without evidence of clinically manifested active TB, affects about one-third of the world's population. Approximately 10% of people with LTBI will develop active TB disease in their lifetime, with the majority developing it within the first five years after initial infection. Currently available treatments have an efficacy ranging from 60% to 90%. Systematic testing and treatment of LTBI in at-risk populations is a critical component of WHO's eight-point framework adapted from the End TB Strategy to target pre-elimination and, ultimately, elimination in low incidence countries. OVERVIEW: Recognizing the importance of expanding the response to LTBI, in 2014 WHO developed Guidelines on the Management of Latent Tuberculosis Infection. The guidelines are primarily targeted at high-income or upper middle-income countries with an estimated TB incidence rate of less than 100 per 100 000 population, because they are most likely to benefit from it due to their current TB epidemiology and resource availability. The overall objective of the guidelines is to provide public health approach guidance on evidence-based practices for testing, treating and managing LTBI in individuals with the highest risk of progression to active disease. Specific objectives include identifying and prioritizing at-risk population groups for targeted intervention of LTBI testing and treatment, including defining an algorithm, and recommending specific treatment options. The guidelines are expected to provide the basis and rationale for the development of national guidelines for LTBI management based on available resources, epidemiology of TB including intensity of transmission, the health-care delivery system of the country, and other national and local determinants.

It is estimated that one third of the world's population is infected with Mycobacterium tuberculosis (the bacterium that causes tuberculosis (TB)), and that each year, about 9 million people develop TB, of whom about 2 million die. Of the 9 million annual TB cases, about 1 million (11%) occur in children (under 15 years of age). Of these childhood cases, 75% occur annually in 22 high-burden countries that together account for 80% of the world's estimated incident cases. In countries worldwide, the reported percentage of all TB cases occurring in children varies from 3% to more than 25%. The Stop TB Strategy, which builds on the DOTS strategy developed by the World Health Organization (WHO) and the International Union Against TB and Lung Disease, has a critical role in reducing the worldwide burden of disease and thus in protecting children from infection and disease. The management of children with TB should be in line with the Stop TB Strategy, taking into consideration the particular epidemiology and clinical presentation of TB in children. These consensus guidelines were produced to help the National Tuberculosis Programmes on the management of tuberculosis in children.

This work contains updated and clinically relevant information about tuberculosis. It is aimed at providing a succinct overview of history and disease epidemiology, clinical presentation and the most recent scientific developments in the field of tuberculosis research, with an emphasis on diagnosis and treatment. It may serve as a practical resource for students, clinicians and researchers who work in the field of infectious diseases.

The WHO consolidated guidelines on tuberculosis. Module 2: screening – systematic screening for tuberculosis disease is an updated and consolidated summary of WHO recommendations on systematic screening for tuberculosis (TB) disease, containing 17 recommendations for populations in which TB screening should be conducted and tools to be used for TB screening. TB screening is strongly recommendations for household and close contacts of individuals with TB, people living with HIV, miners exposed to silica dust, and prisoners. In addition, screening is conditionally recommended for people with risk factors for TB attending health care, and for communities with risk factors for TB and limited access to care (e.g. homeless, urban poor, refugees, migrants). General population screening is recommended in high-burden settings (0.5% prevalence or higher). Symptoms, chest radiography (CXR), and molecular WHO-recommended rapid diagnostic tests for TB are recommended as screening tools for all adults eligible for screening. Computer-aided detection programmes are recommended as alternatives to human interpretation of CXR in settings where trained personnel are scarce. For people living with HIV, C-reactive protein is also a good screening tool. This guideline document is accompanied by an operational handbook, the WHO operational handbook on tuberculosis. Module 2: screening – systematic screening for tuberculosis disease, that presents principles of screening, steps in planning and implementing a screening programme, and algorithm options for screening different populations.

Between 2011 and 2019, WHO has developed and issued evidence-based policy recommendations on the treatment and care of patients with DR-TB. These policy recommendations have been presented in several WHO documents and their associated annexes, including the WHO Consolidated Guidelines on Drug Resistant Tuberculosis Treatment, issued by WHO in March 2019. The policy recommendations in each of these guidelines have been developed by WHO-convened Guideline Development Groups, using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach to summarize the evidence, and formulate policy recommendations and accompanying remarks. The present WHO Consolidated Guidelines on Tuberculosis, Module 4: Treatment - Drug-Resistant Tuberculosis Treatment includes a comprehensive set of WHO recommendations for the treatment and care of DR-TB. The document includes two new recommendations, one on the composition of shorter regimens and one on the use of the BPaL regimen (i.e. bedaquiline, pretomanid and linezolid). In addition, the consolidated guidelines include existing recommendations on treatment regimens for isoniazid-resistant TB and MDR/RR-TB, including longer regimens, culture monitoring of patients on treatment, the timing of antiretroviral therapy (ART) in MDR/RR-TB patients infected with the human immunodeficiency virus (HIV), the use of surgery for patients receiving MDR-TB treatment, and optimal models of patient support and care. The guidelines are to be used primarily in national TB programmes, or their equivalents in Ministries of Health, and for other policy-makers and technical organizations working on TB and infectious diseases in public and private sectors and in the community.

Infectious diseases are the leading cause of death globally, particularly among children and young adults. The spread of new pathogens and the threat of antimicrobial resistance pose particular challenges in combating these diseases. Major Infectious Diseases identifies feasible, cost-effective packages of interventions and strategies across delivery platforms to prevent and treat HIV/AIDS, other sexually transmitted infections, tuberculosis, malaria, adult febrile illness, viral hepatitis, and neglected tropical diseases. The volume emphasizes the need to effectively address emerging antimicrobial resistance, strengthen health systems, and increase access to care. The attainable goals are to reduce incidence, develop innovative approaches, and optimize existing tools in resource-constrained settings.