CPH Exam - Public Health Biology and Human Disease Risk Questions with correct Answers

CPH Exam - Public Health Biology and Human Disease Risk Questions with correct Answers Public Health Based on the premise that health events are not random and that they occur as a result of risk factors. Risk Factors Are not randomly distributed in the population and are influenced by biological and social determinants of health. Role of Public Health 1. Determine causes of disease (etiology) 2. Determine environmental factors that play a role 3. Understand the mechanisms Models of Disease Causation - Epidemiological Triad/Triangle Explains infectious disease. Illustrates the relationship between agent, host and environment Epidemiologic Triad Chain of Infection Model How pathogenic microorganisms are transmitted from one person to another: 1. Causative agent 2. Reservoir 3. Portal of Exit 4. Mode of Transmission 5. Portal of Entry 6. Susceptible Host Germ Theory - Theory of Infectious disease Louis Pasteur - specific disease is caused by specific cause of micro organism. Pasteurization Koch's Postulates Explains transmission of organism to the host. Consists of 4 criteria designed to establish causal relationship between causative microbe and disease. Organism from infected host can be grown in a culture and cause a disease when transmitted to a healthy host. (Note: not all causative agents cause disease). All 4 do not need to be met to establish causality A Mosquito bites an individual who later develops a fever and abdominal rash. What type of transmission would this be? Biological Vector 3 multiple choice options Mechanical Vector Transmission Carries a pathogen from one host to another without being infected itself Biological Vector Transmission Carries a pathogen from one host to another after becoming infected itself (typically an arthropod). Pathogen reproduces in a biological host A blanket belonging to a child who has chickenpox is contaminated with varicella-zoster virus, the virus that causes chickenpox. What is the blanket called? Fomite 3 multiple choice options Fomites Inanimate objects that serve as a mechanism for transfer between hosts. Classic example is a water fountain Biological Insect Vectors The infectious agent that causes malaria is known as which of the following Protozoan Parasite 3 multiple choice options SEIR Infection Model Susceptible, exposed, infectious, recovered Simulate progress of epidemic in a human population LPi: Latency period IPi: Infectious period ti: First time individual is exposed to the virus xLP: Number of days for an exposed individual to become infective xIP: Number of days for an individual to recover from a disease Why is surveillance important? -Monitoring disease trends -Describing natural history of the disease -Identifying epidemics or new syndromes -Monitoring changes in infectious agents -Identifying areas for research -Planning, public health policy -Evaluating public health policies/interventions Passive Surveillance (surveillance system) Local and state health departments rely on health care providers or laboratories to report cases of disease, The majority of public health surveillance systems are passive. Passive Surveillance - Advantages Efficiency Simple and requires relatively few resources Occurs continuously Passive Surveillance - Disadvantages incomplete data due to underreporting Active Surveillance Health departments contact health care providers and laboratories requesting information about conditions or disease. Active Surveillance - Advantages More complete data Occurs when proactively requesting information - Is useful when you must identify all cases. Active Surveillance - Disadvantages Requires resources and time Strategies to prevent epidemics and spread of disease -Pasteurization -Disinfection (hand washing) -Barrier contraceptive methods -Antibiotics -Quarantines -Vaccines Immune System Network of organs, cells, tissues: -Skin -Lymphatic System -Thymus -Bone marrow -Spleen -White blood cells (leukocytes) Which of the following best describes how vaccines work? Most vaccines work by triggering the body's adaptive immune system, including antibody production that can target a specific pathogen. 3 multiple choice options Acquired Immunity Immunity that develops during your lifetime Which of the following best describes herd immunity? Resistance within a population to a certain infection. 3 multiple choice options Herd immunity threshold New vaccines for influenza must be developed every year because: New strains of the virus evolve that are not affected by existing vaccines 2 multiple choice options Antigenic drift (Influenza) -Minor change within subtype (point mutations) -May caused epidemics -Occurs in A and B Influenza subtypes - This is why we need flu vaccines every year Antigenic shift (Influenza) Major Change (new subtype, exchange of gene segments) Occurs only in A subtypes May cause pandemic Disease is usually caused by: Complex interactions between genes and environment (air we breathe, what we eat, etc. ) Demographic Transition Shows population change over time. How birth and death rates affect the overall population of a country. Compared with 1900, the prevalence of deaths due to infectious disease in the USA is: Much less 3 multiple choice options The most important reason for reduced mortality during the initial stage of a demographic/epidemiologic transition in a population is: Improved sanitation 3 multiple choice options Which of these groups or conditions include one or more single gene disorders that are part of recommended uniform newborn screening panel? All of the above 3 multiple choice options Which of the following is true about newborn screening problems Most of the genetic conditions screened for follow an autosomal recessive pattern of inheritance 3 multiple choice options Screening Screening identifies individuals who may be at an increased risk for a certain disease. Early detection -> Early treatment Environmental Teratogens agents that induce structural abnormality, growth deficiency, or functional alteration during prenatal development.