MLSP-GROUP power point in medical laboratory science .pptx

about epidemiology & disease transmission

1. EPIDEMIOLOGY & DISEASE TRANSMISSION

2. Table of contents TRANSMISSION 01 INDIRECT TRANSMISSION 03 DESCRIPTIVE EPIDEMIOLOGY (Secular and Periodic Trend) 04 DIRECT TRANSMISSION 02

3. Table of contents DESCRIPTIVE EPIDEMIOLOGY (Seasonal and Epidemic Occurrence ) 05 ANALYTIC EPIDEMIOLOGY (Cohort Method) 07 EXPIREMENTAL EPIDEMIOLOGY 08 ANALYTIC EPIDEMIOLOGY (Case Control Method) 06

4. WHAT IS TRANSMISSION ? -the action or process of transmitting something, or the state of being transmitted. (Oxford Languages)

5. MODES OF TRANSMISSION -An infectious agent may be transmitted from its natural reservoir to a susceptible host. Direct Indirect • Direct contact • Droplet spread • Airborne • Vehicle borne • Vector borne (mechanical or biologic)

6. DIRECT TRANSMISSION -An easy way to catch most infectious diseases is by coming in contact with a person or an animal with the infection

7. SKIN TO SKIN CONTACT Kissing • Mononucleosis (“kissing disease”) - a contagious infection caused by a herpes virus called Epstein-Barr. Sexual intercourse • Human Papillomavirus (HPV) -Most common sexually transmitted infection. They can infect the genitals, mouth or throat. Gonorrhea -an infection caused by a sexually transmitted bacterium that infects both males and females

8. SKIN TO SKIN CONTACT Droplet Spread -Refers to spray with relatively large, short-range aerosols produced by sneezing, coughing, or even talking. Contact with contaminated soil • Hookworm Is an intestinal parasite of humans. Humans contract hookworms through hookworm larvae found in dirt contaminated by feces. Meningococcal -Refers to any illness caused by bacteria called Neisseria meningitidis, also known as meningococcus Pertussis -Also known as whooping cough, is a highly contagious respiratory disease. It is caused by the bacterium Bordetella pertussis.

9. INDIRECT TRANSMISSION - refers to the transfer of an infectious agent from a reservoir to a host by suspended air particles, inanimate objects, or animate intermediaries.

10. EXAMPLES OF INDIRECT TRANSMISSION • Airborne Transmission • Contaminated objects • Contaminated Food and water • Animal-to-person contact • Animal reservoirs • Insect bites (vector-borne disease) • Environmental reservoirs

11. EPIDEMIOLOGIC METHODS DESCRIPTIVE EPIDEMIOLOGY ANALYTIC EPIDEMIOLOGY EXPERIMENTAL EPIDEMIOLOGY The three major epidemiologic techniques are:

12. DESCRIPTIVE EPIDEMIOLOGY -In descriptive epidemiology, the data that describe the occurrence of the disease are collected by various methods from all relevant sources. The data are then collated by time , place , and person . TIME - is important in characterizing illness to assess if incidence rates or case numbers have increased or decreased over time and if there is seasonal variation. In outbreaks, the relationship between time and the number of illnesses is graphically displayed in an epidemic curve .

13. SAMPLE EPI CURVE

14. Events of significance to the outbreak: a. Exposures (e.g., mass gathering event, implicated dinner) b. Public health measures (e.g., restaurant closure, product recall) c. Communications (e.g., media release warning public not to consume implicated food)

15. ANALYSING AN EPI CURVE: a. Size b. Time trend c. Outliers d. Pattern of spread ✓ Point source ✓ Continuous source ✓ Propagated source Intermittent source

16. Place Pathogens do not necessarily respect or follow political borders. An examination of the spatial associations of cases can play a key role in determining the source of the outbreak. Person People’s socio-demographic characteristics and behaviors can increase or decrease their risk for developing an illness.

17. Four trends to be considered in describing the epidemiologic data: A. SECULAR TREND B. PERIODIC TREND C. SEASONAL TREND D. EPIDEMIC OCCURRENCE

18. SECULAR TREND (AKA LONG TIME TREND) - Describes the occurrence of disease over a prolonged period, usually years; it is influenced by the degree of immunity in the population and possibly nonspecific measures such as improved socioeconomic and nutritional levels among the population.

19. PERIODIC TREND - A temporary modification in the overall secular trend, the periodic trend may indicate a change in the antigenic characteristics of the disease agent. -Lowering of the overall immunity of a population or a segment thereof can result to an increase in the occurrence of the disease.

20. DESCRIPTIVE EPIDEMIOLOGY (SEASONAL and EPIDEMIC OCCURRENCE)

21. SEASONAL TREND reflects the seasonal changes in disease occurrence following changes in environmental conditions that enhance the ability of the agent to replicate or be transmitted. Ex: Measles Chickenpox

22. EPIDEMIC OCCURENCE - an epidemic is a sudden increase in occurrence due to prevalent factors that support transmission. Ex: Dengue

23. Three different sites considered in the description of epidemiologic data by place: • Where the individual was when the disease occurred • Where the individual was when he or she became infected from the source • Where the source became infected with the etiologic agent.

24. • The third focus of descriptive epidemiology is the infected person. • All pertinent characteristics should be noted: age, sex, occupation, personal habits, socio economic status, immunization history, presence of underlying disease, and other data.

25. ANALYTIC EPIDEMIOLOGY (Case Control Method -First approach to test hypothesis -Both effect and outcome have occurred before the onset of the study -Study proceeds backwards (from effect to cause). -Uses a Cases and Control or Comparison group to support an interference. CASE STUDY Cases - People with the disease Control - People without the disease

26. How to Select the Case and the Control Group CASE 1. Diagnostic Criteria - Disease and stage of the disease must be specified. 2. Eligibility Criteria - selecting people who have just developed the disease(new cases only). Where can we find them? -Hospitals -Community

27. How to Select the Case and the Control Group CONTROL They must be: •Free from the disease •Be similar to the cases except for the absence of disease. Where can we find them? -Hospitals -Relatives -Community

28. ANALYTIC EPIDEMIOLOGY (Cohort Method) -It observes a group of people that shares a same characteristics. What is cohort method?

29. 1. Prospective- forward-looking 2. Retrospective- backward-looking Two types of cohort:

30. Advantages: • Find incidence of new disease • Find out association • Disadvantages • Long-term studies Expensive

31. EXPERIMENTAL EPIDEMIOLOGY a hypothesis developed and an experimental model is constructed in which one or more factors may be manipulated manipulation will either confirm or disprove the hypothesis

32. Independent Dependent Control 3 EXPERIMENTAL VARIABLES

33. 3 TYPES OF CASES IN EXPERIMENTAL EPIDEMIOLOGY 1. RANDOMIZED CONTROL TRIAL 2. FIELD TRIAL 3. COMMUNITY TRIAL

34. EPIDEMIC INVESTIGATION -describes the factors relevant to an outbreak of disease -data are collected, collated according to time place and person and analyzed and inferences are drawn

35. DIFFERENCES BETWEEN ENDEMIC, EPIDEMIC and PANDEMIC Endemic Pandemic Epidemic

36. REFERENCES: Centers for Disease Control and Prevention ( nd ). Section 7: Analytic Epidemiology. Retrieved from https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section7.html Outbreak Toolkit. (n.d.). Epidemic curves – Outbreak Toolkit . Retrieved November 11, 2021, from https://outbreaktools.ca/background/epidemic-curves/ Outbreak Toolkit. (n.d.-a). Descriptive epidemiology – Outbreak Toolkit . Retrieved November 11, 2021, from https://outbreaktools.ca/background/descriptive-epidemiology/ Brachman, P. (n.d.). NCBI - Chapter 9 Epidemiology . NCBI. Retrieved November 11, 2021, from https://www.ncbi.nlm.nih.gov/books/NBK7993/

37. REFERENCES: Deputy Director for Public Health Science and Surveillance, Center for Surveillance, Epidemiology, and Laboratory Services, Division of Scientific Education and Professional Development. (2012, May 18). Principles of Epidemiology | Lesson 1 - Section 6 . CDC. Retrieved November 11, 2021, from https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section6.html Valencia, H. (2017) . How diseases are transmitted? Retrieved from https://www.healthline.com/health/disease-transmission#indirect-contact Centers for Disease Control and Prevention. (2012) . Retrieved from https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section10.html https://www.mayoclinic.org/diseases-conditions/infectious-diseases/symptoms-causes/syc-20351173#:~:text=An%20easy%20way%20to%20catch,Person%20to%20person Book: Mayo Clinic Family Health Book, 5th Edition 1998-2021 Mayo Foundation for Medical Education and Research (MFMER).  

38. REFERENCES: https://my.clevelandclinic.org/health/diseases/13974-mononucleosis#:~:text=Mononucleosis%20(mono)%20is%20a%20contagious,fatigue%2C%20fever%20and%20body%20aches 9500 Euclid Avenue, Cleveland, Ohio 44195 | 800.223.2273 | © 2021 Cleveland Clinic. All Rights Reserved .   https://www.cdc.gov/std/general/default.htm#:~:text=Human%20papillomavirus%20(HPV)%20is%20the,can%20be%20prevented%20with%20vaccines U.S. Department of Health & Human Services USA.gov.223.2273   https://www.mayoclinic.org/diseases-conditions/gonorrhea/symptoms-causes/syc-20351774 998-2021 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved..S .

39. REFERENCES: https://hellodoctor.com.ph/sexual-wellness/gonorrhea/gonorrhea-causes/?amp=1 Written by Maridol Ranoa-Bismark Updated Jul 01Medically reviewed by Mary Rani Cadiz, M.D. ©2021 Hello Health Group Pte. Ltd. All Rights Reserved.   https://www.nfid.org/infectious-diseases/hpv/ Centers for Disease Control and Prevention National Foundation for Infectious Diseases 7201 Wisconsin 7201 Wisconsin Avenue Suite 750 Bethesda, MD 20814 301.656.0003   1629 K Street, NW Suite 300 Washington, DC 20006

40. REFERENCES: https://www.health.ny.gov/publications/2168/ New York State Department of Health Corning Tower, Room 2364 Albany, New York 12237-0044   https://www.news-medical.net/health/What-is-whooping-cough.aspx By Dr. Ananya Mandal, MD Reviewed by April Cashin-Garbutt, MA (Editor News-Medical.net - An AZoNetwork Site Owned and operated by AZoNetwork , © 2000-2021   https://www.cdc.gov/pertussis/index.html U.S. Department of Health & Human Services USA.gov CDC Website Exit Disclaimer external icon

41. REFERENCES: (What is cohort study?) Cohort study: Finding causes, examples, and limitations (medicalnewstoday.com)   (Advantages and disadvantages; types of cohort studies) Cohort Studies..... Made Easy !!! – YouTube Transmission. transmission noun - Definition, pictures, pronunciation and usage notes | Oxford Advanced Learner's Dictionary at OxfordLearnersDictionaries.com. (n.d.). Retrieved November 12, 2021, from https://www.oxfordlearnersdictionaries.com/us/definition/english/transmission . Medical Microbiology - NCBI Bookshelf https://www.ncbi.nlm.nih.gov/books/NBK7993/

42. REFERENCES: Medicine (2021) https://www.medicinenet.com/difference_between_an_epidemic_and_a_pandemic/article.htm#:~:text=According%20to%20the%20Center%20for,across%20several%20countries%20or%20continents . Section 6: Descriptive Epidemiology - https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section6.html National Library of Medicine. (n.d.). Dependent and Independent Variables. https://www.nlm.nih.gov/nichsr/stats_tutorial/section2/mod4_variables.html I Hate PSM. (n.d.). Epidemiology: Types of Epidemiological Studies. http://www.ihatepsm.com/blog/epidemiology-types-epidemiological-studies

43. REFERENCES: Herrero, L., & Madzokere , E. (2021, September 23). COVID-19 will likely shift from pandemic to endemic — but what does that mean?. https://www.weforum.org/agenda/2021/09/covid-pandemic-epidemic-disease-coronavirus/ Intermountain Healthcare. (2020, April 2). What’s the difference between a pandemic, an epidemic, endemic, and an outbreak?. https://intermountainhealthcare.org/blogs/topics/live-well/2020/04/whats-the-difference-between-a-pandemic-an-epidemic-endemic-and-an-outbreak/ Kante , E. (2016, October 14). Field trials. https://www.slideshare.net/ELISHAJR/field-trials Stephanie. (2014, December 12). Manipulated Variable: Definition. https://www.statisticshowto.com/manipulated-variable/

44. MEMBERS: ANDREA BERNADETTE PANGAN ANA MARIE PASCUAL RACHEL ANN RAMOS CRIZABELLE RIVERA MYLENE RIVERA KRISTINE RODRIGUEZ BAMBI ALAIZA ORTIZ XYRA PAMELA SANTIAGO DONIELLA MARIZ VILLAMOR

45. THANK YOU FOR LISTENING!