chapter 37:Epidemiology and public health microbiology – Flashcards
Unlock all answers in this set
Unlock answersquestion
            epidemiology
answer
        science that evaluates occurence, determinants, distribution and control of health and disease in a defined human population.
question
            epidemiologist
answer
        one who practices epidemiology
question
            john snow
answer
        first epidemiologist studied cholera in london
question
            CDC center for disease control and prevention
answer
        in atlanta, GA national focus for developing and applying disease prevention and control envronmental health health promotion and health education activities designed to improve the health of the people.
question
            world health organization
answer
        wouldwide counterpart located in geneva, switzerland
question
            what does epidemiology do?
answer
        determines causative agent, source/ reservoir of disease agent, mechanism of transmission, host and evironmental factors that facilitate development of disease within a defined population, best control measures.
question
            sporadic disease
answer
        occurs occasionally and at irregular intervals.
question
            endemic disease
answer
        maintains a relatively steady low-level frequency at a moderately regular interval.
question
            hyperendemic disease
answer
        gradually increase in occurrence frequency above endemic level but not epidemic level.
question
            outbreak
answer
        sudden unexpected occurrence of disease, usually focal or in a limited segment of population
question
            epidemical
answer
        sudden increase in frequency above expected number  index case
question
            index case
answer
        first case in an epidemic
question
            pandemic
answer
        increase in disease occurrence within large population over wide region (usually worldwide)
question
            public heath surveillance
answer
        protect populations, improving the health of communities via education, promotion of healthy lifestyles and prevention of disease and injury.
question
            methodical approach to identify issues
answer
        review of death certificates, field investigation of epidemics, and investigation of actual cases
question
            measuring the infectious frequency
answer
        to determine if an outbreak, epidemic or pandemic is occuring, epidemiologist mesure the disease frequency at a single time points and over time.  -statistics
question
            statistics
answer
        mathematics dealing with collection, organization and interpretation of numerical data important statistical measures of disease frequency
question
            morbidity rate prevalence rate mortality rate
answer
        three important statistical measures of disease frequency
question
            morbidity rate
answer
        incidental rate number of new cases in a specific time period per unit of population   # of new cases during specific time/ # of individual in a population
question
            prevelance rate
answer
        total number of individuals infected at any one time, depends both on incidence rate and duration of illness.
question
            mortality rate
answer
        number of deaths from a disease per number of cases of the disease # deaths due to given disease/ size of total population with disease
question
            infectious disease
answer
        disease resulting from an infection by microbial agents such as viruses, bacteria, fungi, protozoa, and helminths.
question
            communicable disease
answer
        can be transmitted from one host to another.
question
            two types of epidemics
answer
        common source epidemic propagated epidemic
question
            common source epidemic
answer
        single common contaminated source (food) faster and kills more but once source is found and iliminated, the disease dies off fast.
question
            propagated epidemic
answer
        one infected individual into a susceptible group, infection propagated to other  slow takes longer time
question
            how do we recognize and measure infectious disease in a population?
answer
        survelillance methods are used gather information on development and occurrence of a disease collating and analyzing the data summarizing the findings selecting control methods.
question
            WHO
answer
        Graphic representation of epidemiological data  confirmed human cases of avian influenza A (h5n1) from 2003-2012
question
            herd immunity
answer
        resistance of a population to infection and to spread of an infectious organism because of the immunity of a large percentage of the population -however, levels can be altered by introducing new susceptible individuals into the population  public health services recomend at least 70% of population should be immunized against common infectious disease.
question
            Herd immunity levels
answer
        levels can be altered by changes in pathogen -antigenic shift -antigenic drift
question
            antigenic shift
answer
        major change in antigenic character of pathogen
question
            antigenic drift
answer
        smaller antigenic changes
question
            emerging and reemerging diseases
answer
        infectious disease mortality has increased since 1982 in the us -incidents of infectious disease due to emerging microbial population -some novel or reemerging infectious diseases.
question
            hot spots of emerging infectious diseases?
answer
        northeast U.S., west europe, japan and southeast Australia.
question
            systematic epidemiology
answer
        focuses on ecological and social factors that influence development and spread of emerging and reemerging diseases. many factors identified.
question
            reasons for emerging and reemergind diseases
answer
        world wide population growth increased international travel habitat disruption microbial evolution and development resistance  inadequate public infrastructures.
question
            other reasons for emerging and reemerging of diseases
answer
        changes in ecology and climate social unrest wars and bioterrorism changes in food processing and agricultural practices changes in human behavior, technology and industry medical practices that lead to immunosuppression.
question
            nosocomial infections
answer
        hospital acquired infections -from pathogens within a hospital or other clinical care facility, acquired by patients in the facility.  -10% of all hospital patients acquire a nosocomial infection .often caused by bacteria that are members of normal microbiota many hospital strains are antibiotic resistant
question
            endogenous pathogen
answer
        brought into hospital by patient or acquired when patient is colonized after admission
question
            exogeneous pathogen
answer
        microbiota other than the patients
question
            autogenous infection
answer
        caused by an agent derived from microbiota of patient despite whether it became part of patients microbiota following admission.
question
            nosocomial infections control
answer
        prolong hospital stays by 4-13 days results in over 4.5 billion costs results in 20k-60k deaths annually  must do proper training of personnel in basic infection control measures (handing surgical wounds and hand washing) monitor patient for signs and symptoms of nosocomial infection
question
            hospital epidemiologist
answer
        accreditation by the joint commision on accreditation of healthcare organization must have designated individual directly responsible for developing and implementing policies to monitor and control infections and communicable diseases.  -reports to infection control committee or similar group.
question
            how to control the infection?
answer
        -reduce/eliminate source or reservoir of infection -break connection between source and susceptible individual  -reduce number of susceptible individuals.
question
            reduce or eliminate source or reservoir infection
answer
        quarantine and isolate of cases and carriers destruct animal reservoir treatment of sewage therapy that reduces or eliminates infectivity of cases.
question
            break connection between source and susceptible individuals
answer
        chlorination of water supplies pasteruization of milk supervision and inspection of food and food handlers destruction of insect vectors with pesticides.
question
            Reduce number of susceptible individuals
answer
        -raise herd immunity -passive immunity following exposure -active immunity for protection
question
            vaccines
answer
        preparation of microbial antigens used to induce protective immunity. -may consist of killed, living, weakened microbes or inactivated bacterial toxins, purified cell material recombinant vectors or dna.
question
            immunization
answer
        result obtained when vaccine stimulates immunity -vaccine attempt to induce antibodies and activated T cells to protect host from future infection
question
            vaccinomics
answer
        application of genomics and bioinformatics to vaccine development.
question
            Adjuvants
answer
        mixed with antigens in vaccines to enhance the rate and degree of immunization -can be any nontoxic material that prolongs antigen interaction with immune cells and stimulates the immune response to the antigen. -several types are available such as oil in water emulsion, alum and beeswax.
question
            immunized hosts
answer
        vaccination of children shoud begin at 2 months more vaccination depends on relative risk ( living in close communitites, reduced immunity, international travelers, health care workers)
question
            global health considerations
answer
        500K infectious disase deaths in developed countries 18 mil infectious disease deaths in less developed countries.
question
            precautions needed for
answer
        global travel, clean water, sanitation, health care infrastructure and vaccination
question
            whole cell vaccines
answer
        most current vaccines active against bacteria and viruses and they consist of two microbes that are either inactivated (killed) or attenuated (live but avirulent)
question
            may be problamatic
answer
        may not protect, immunosuppressed at risk of getting disease, and attenuated may revert to virulent.
question
            Acellular or subunit vaccines
answer
        use of purified moecules from microbes avoids some of the risk of whole cell vaccines.  forms of subunit vaccines
question
            forms of subunit vaccines
answer
        capsular polysaccharides, recombinant surface antigens and inactivated exotoxins. (toxoids)
question
            recombinant vector vaccines
answer
        pathogen genes that encode major antigens inserted into non-virulent viruses or bacteria which sere as vectors and express inserted gene  released gene products (antigens) can elicit cellular (t cells) and humoral immunity (b cells).
question
            dna vaccines
answer
        dna directly introduced into host cell via air pressure or gene gun  -dna is taken into the nucleus and pathogens dna fragment is expressed.  host immune system responds to foreign proteins produced.   many dna vaccine trials are currently being run.
question
            epidemiological guardian
answer
        role of public health system -network of health professionals involved in surveillance, diagnosis and control of epidemics  -form county, regional, state, national, and international public health organizations.
question
            bioterrorism preparedness
answer
        intentional or threatened use of viruses, bacteria, fungi or toxins from living organisms to produce death or disease in humans, animals, and plants.
question
            salmonella typhimurium
answer
        1984 in dalles OR, in 10 restaurant salad bars. intentional use of agents. caused hospitalization
question
            shigella dsentariae
answer
        intentional relaease of bacteria in a hospital lab break room. caused hospitalization
question
            bacillus anthracis
answer
        2oo1 in seven easter us states, use of weaponized spores delivered through us portal systems.  resulted in 5 deaths
question
            choosing biological agents as weapons
answer
        biocrime when chosen as a means for a localized attack vs bioterrorism when chosen for mass casualties.
question
            characters that favor the use of biological agents as weapons
answer
        invisible, odorless, and tasteless difficult to detect take hours or days before awareness that they have been used fear and panic associated with anticipation that they were used.
question
            U.S. Biological weapons defense initiative
answer
        -procurement of specialized vaccines and medicines for a national civilian protection stockpile.  -invigoration of biodefense research including genome sequencing, vaccine, and therapeutic research.  -develop improved detecting and diagnostic systems -prepare of health care professional to be member of first responder team.
question
            Public health security and bioterrorism preparedness and response act
answer
        identified "select" agents whose use is tightly regulated   2005 final rules issued
question
            department of homeland security
answer
        established to coordinate the defense of the us against terrorist attacks.  -responsible for developing/maintaining a national incident management system to monitor large scale hazards.
question
            partner to protect us population
answer
        CDC partner with academic institutions to educate health care providers.  establish centers for public health relatedness  established centers for public health preparedness
question
            Laboratory response network (LRN)
answer
        ensures effective laboratory response to terrorism (improves us public health lab infrastrucutre) -CDC manged program partener with FBI and association of Public health labs (APHL) CDC managed program
question
            indicator of bioterrorism
answer
        sudden increase numbers of sick people, especially with unusual disease for that place or time of year.  sudden increase numbers of zoonoses, diseased animals, or vehicle borne illnesses
