L 32 - Prevention of TB Presentation PDF

RES 301 Prevention of TB Dr Mohammed Abdulrazzaq MD, PHD Assistant Professor Department of Community Medicine February 9, 2025 www.gmu.ac.ae...

RES 301 Prevention of TB Dr Mohammed Abdulrazzaq MD, PHD Assistant Professor Department of Community Medicine February 9, 2025 www.gmu.ac.ae COLLEGE OF  Content 1. Ethics of TB prevention 2. Global TB Strategy 3. Levels of prevention 4. Prevention of Infectious disease  Learning Outcomes 1. Assess the factors affecting successful prevention 2. Differentiate between various levels of prevention History of TB 1882 TB bacilli identified by Koch 1907 TST - tuberculin skin test (von Pirquet) 1919 BCG – Bacille Calmette & Guerin vaccine 1943 Schatz & Waksman discover streptomycin 1948 BMRC trial of streptomycin vs bed rest 1952 Development of isoniazid 1966 Development of rifampicin 1978 Short course chemotherapy (DOTS)* *Directly Observed Treatments Ethics of Tuberculosis Prevention 5 Background TB ranks as the second leading cause of death from an infectious disease worldwide, after the human immunodeficiency virus (HIV). Estimated 9 million people who developed TB in 2013 56% in South-East Asia and Western Pacific Regions 25% in African Region Between 1990 and 2013: 45% decrease in TB mortality rate *WHO: Global 41% decrease in TB prevalence rate Tuberculosis Report 2014 6 Post 2015 Global TB Strategy VISION A TB-free world Zero deaths, disease, and suffering due to TB GOAL End the global tuberculosis epidemic MILESTONES FOR 2025 75% reduction in TB deaths (compared with 2015) 50% reduction in TB incidence rate (less than 55 TB cases per 100 000 population) No affected families facing catastrophic costs due to TB TARGETS FOR 2035 95% reduction in TB deaths (compared with 2015) 90% reduction in TB incidence rate (less than 10 TB cases per 100 000 population) No affected families facing catastrophic costs due to TB *WHO: Global strategy and targets for tuberculosis prevention, care and control after 2015. 2015 7 Principles of post-2015 Global TB Strategy Government stewardship and accountability, with monitoring and evaluation Strong coalition with civil society organizations and communities Protection and promotion of human rights, ethics and equity Adaptation of the strategy and targets at the country level, with global collaboration *WHO: Global strategy and targets for tuberculosis prevention, care and control after 2015. 2015 8 Disease Prevention and Control Every disease has certain weak points susceptible to attack. The basic approach to controlling disease is to identify these weak points and break the weakest links in the chain of transmission. This requires sound epidemiological knowledge of the disease, the natural history of the disease, distribution in time, place, and person, multifactorial causation, sources of infection, and dynamics of transmission. Prevention The goals of medicine are to promote health, preserve health, restore health when it is impaired, and minimize suffering and distress. These goals are embodied in the word "prevention" Prevention; Definition and Concept Actions aimed at eradicating, eliminating, or minimizing the impact of disease and disability. In the modern day, the concept of prevention has become broad-based. It has become customary to define prevention in terms of these levels: primordial prevention primary prevention secondary prevention tertiary prevention Primordial prevention Primordial prevention consists of actions and measures that inhibit the emergence of risk factors in the form of environmental, economic, social, and behavioral conditions and cultural patterns of living, etc. It is the prevention of the emergence or development of risk factors in countries or population groups in which they have not yet appeared. Primordial Prevention methods for pulmonary TB such as Improving living conditions Promoting good nutrition Education and awareness programs Strengthening healthcare infrastructure Preventing migration to high-risk areas Primary prevention Primary prevention can be defined as the action taken prior to the onset of disease, which removes the possibility that the disease will ever occur. It signifies intervention in the pre-pathogenesis phase of a disease or health problem. Primary prevention may be accomplished by measures of “Health promotion” and “specific protection” Example Primary prevention methods for Pulmonary TB BCG Proper ventilation for workplace/house to protect the persons in contact with TB patient Proper Face mask (N95) for persons in contact with TB patient Prophylactic chemotherapy for immunocompromised patients and contact with TB patient.  Primary prevention Achieved by Health promotion Specific protection Immunization and seroprophylaxis Health education chemoprophylaxis Environmental modifications Use of specific nutrients or supplementations Protection against occupational hazards Nutritional interventions Safety of drugs and foods Lifestyle and behavioral changes Control of environmental hazards, e.g. air pollution Secondary prevention It is defined as “ action which halts the progress of a disease at its incipient stage and prevents complications.” The specific interventions are early diagnosis (e.g. screening tests, and case-finding programs….) and adequate treatment. For infectious diseases, It thus protects others in the community from acquiring the infection and thus provides at once secondary prevention for the infected ones and primary prevention for their potential contacts. Tertiary prevention It is used when the disease process has advanced beyond its early stages. It is defined as “all the measures available to reduce or limit impairments and disabilities, and to promote the patients’ adjustment to irremediable conditions.” Tertiary Interventions that should be accomplished in the stage of tertiary prevention are disability, limitation, and rehabilitation. Disability limitation: disease impairment disability handicap  TB Disease in Weakened Persons More likely to get TB disease when a person’s body is weakened from: HIV Diabetes Poor Nutrition Cancer medications Steroids Drug use Cavity Smoking Old Age  TB Disease in Weakened Persons… Primary Prevention is the best… The BCG vaccine is generally not recommended for people with compromised immune systems like those with HIV but start prophylactic antibiotics. The best approach is to start Antiretroviral Therapy (ART) to boost the immune system and consider Isoniazid Preventive Therapy (IPT) to prevent the progression to active TB). Cavity  Examples of uses of levels of prevention All three levels of prevention can be used to control a single disease process. 1. BCG Vaccination of newborns (primary prevention). 2. Screening and early treatment of a person with active tuberculosis (secondary prevention) may prevent transmission to another person (primary prevention). 3. In advanced cases of tuberculosis, occupational and social rehabilitation (tertiary prevention) by modification of working conditions may help to regain the capacity to earn his livelihood. September 22, 2014 19 Intervention to Break the Cycle of Infection Control of infectious diseases (the 4 “C”s) Control Cases Contacts Carriers Community Diagnosis notification Epidemiological isolation Observation detection Investigation & Quarantine disinfection containment treatment follow up release The cycle of infection and Interventions to Break Each link -Surveillance/ -Isolation of cases quarantine -Treatment -Chemoprophylaxis -Disinfection - Sero-prophylaxis -Control of carriers - Vaccination -Control of animals Host Reservoir & Source Mode of transmissi -Prevention of overcrowding on -Personal hygiene (MOT) -Vector control -Environmental sanitation September 22, 2014 22 Disease Elimination Between control and eradication, an intermediate goal has been described, called "regional elimination“. The term "elimination" is used to describe the interruption of transmission of disease, for example, the elimination of measles, polio, and diphtheria from large geographic regions or areas. Regional elimination is now seen as an important precursor of eradication. Disease Eradication Eradication literally means to "tear out by roots". It is the process of “Termination of all transmission of infection by the extermination of the infectious agent through surveillance and containment”. Eradication is an absolute process, an "all or none" phenomenon, restricted to the termination of an infection from the whole world. It implies that disease will no longer occur in a population. To date, only one disease has been eradicated, that is smallpox. References Park K. Park’s Textbook of Preventive and Social Medicine, 25th ed. Banarsidas Bhanot; 2019. ISBN No. 9 78-93-82219- 15-6. WHO: Global strategy and targets for tuberculosis prevention, care and control after 2015. 2015 Thank You DISCLAMER The contents of this presentation, can be used only for the purpose of a Lecture, Scientific meeting or Research presentation at Gulf Medical University, Ajman. www.gmu.ac.ae