Public Health Exam 1

Public Health

Mission: fulfillment of society’s interest in assuring the conditions in which people can be healthy

Substance: organized community efforts aimed at the prevention of disease and the promotion of health

Core Functions of Public Health

Assessment - collecting data

Policy Development - traffic laws/consequences, dogs w/ rabies vaccine

Assurance - ensures public health services are provided to communities, trusting expiration date given by government

Assessment

Collecting and evaluating data to identy health needs in populations, like trends and disparities

Policy Development

Setting goals for health services, developing performance standards, and determining how to allocate resources to meet health needs.

• Setting immunization standards for children

Assurance

Ensuring that public health services are provided to communities and individuals

• Making sure that health services, safe environments, and protective laws are actually available, accessible, and high quality for everyone in a community.

• Active follow-through step after planning and setting policies

• “Two-way trust” between public health organization/efforts and served populations

Public Health vs. Medical Care

Public Health

• Patient is the community

• Primarily concerned with cause of disease

• Diagnoses the health of the community using public health sciences

• Goal = prevention - treatment of a community = new policies/interventions

Clinical Service

• Patient is the individual

• Primarily concerned with mechanism of disease

• Diagnosis of diseases or pre-clinical disease state

• Goal = treatment - treatment using pharmaceuticals or through other healthcare activities

Public Health & Politics

Science = how we understand threats to health, determine what interventions might work, evaluate whether those interventions worked

Politics = how, we as society, make decisions on what policies to implement

• Is a part of both policy development and assurance functions of public health

• Community pays for public health initiatives through taxes

Public Health Disciplines

Epidemiology

Statistics

Environmental Health Science

Social and Behavioral Sciences

Health Policy and Management

Epidemiology

Study of epidemics

• Focuses on human populations, usually starting w/ outbreak of disease in a community

• Aims to control spread of infectious diseases

• Seeks causes of chronic disease and ways to limit harmful exposures

Statistics

Government collects health data on population

• Numbers are diagnostic tools for the health of the community

• Statistics is used to calculate risks and benefits

  • Integral part of any epidemiology study seeking disease cause

  • integral part of any clinical study testing the effectiveness of a new drug

Environmental Health Science

Health is affected by exposure to environmental factors:

• Air Quality

• Water Quality

• Solid and hazardous wastes

• Safe food and drugs

• Global environmental change

Social and Behavioral Sciences

Theory of health behavior = social environment affects people’s behavior

• Major threats: tobacco, poor diet, physical inactivity, and injuries

• Black people have lower life expectancy than white, even when incomes are similar

  • Other ethnic minority groups are also at increased risk for a variety of health problems

Health Policy and Management / Health Administration

Examines the role of medical care in public health

• Cost of medical care in US is out of control

• US has high % of population w/o health incurance

  • These people lack access to medical care

• Quality of medical care can be measured and is often questionable

  • Medical care has eaten up profits that could be used more beneficially for education, housing, environment

Barriers to Health Services

Availability

• The sufficient supply and appropriate stock of health workers, with the competencies and skill-mix to match the health needs of the population

Accessibility

• Equitable distribution of these health workers taking into account the demographic composition, rural-urban mix and under-served areas or populations

Acceptability

• Health workforce characteristics and ability (e.g. sex, language, culture) to treat all patients with dignity, create trust, and promote demand for services

Biomedical Sciences

Understanding control of new diseases and noninfectious diseases

• Chronic Diseases

• Genetics

Understand molecular mechanisms underlying an observed association between a public health exposure and outcome

Prevention and Intervention

Primary prevention prevents an illness or injury from occurring at all

• Active: individual has to make a change to prevent adverse health outcome (e.g. vaccine)

• Passive: no behavioral change needed (e.g. fluoride in water to prevent cavities)

Secondary prevention minimizes the severity of the disease or injury once it has occurred

• Disease already exists in the person

• Cancer screening (mammogram) - highly intervenable at earlt stages = high cure rate

Tertiary prevention minimizes disability by providing medical care and rehab services

• People who already have adverse health outcomes → disease already occurred

• e.g. stroke patient w/ OT rehab

Public Health Approach

1. Define the health problem

2. Identify risk factors associated with the problem

3. Develop and test community-level interventions to control/prevent the cause of the problem

4. Implement interventions to improve the health of the population

5. Monitor interventions to assess effectiveness

Public Health & Natural Disasters

Impact infrastructure of a country → potential to lead to public health crises

• Waste Management

• Water Treatment Facilities

• Delivery of Healthcare Supplies

Epidemiological Surveillance Systems

Systematic collection of data pertaining to the occurrence of specific diseases, analysis and interpretation of these data, dissemination of consolidated and process information to contributors to the program

Types of Surveillance Systems

1. Surveillance systems used to monitor disease trends and plan public health programs

• Vital Statistics

• Disease reporting systems

• Surveys

2. More Specialized Systems

   1. Sentinel surveillance (disease-specific)

   2. Zoonotic disease surveillance

   3. Adverse events surveillance

   4. Syndromic surveillance

   5. Disease Registries

   6. Laboratory surveillance

Vital Statistic Reporting Systems

In the U.S., available from

• National Center for Health Statistics

• State vital records office: volunteer data to feds

• CDC WONDER — online system containing data on births, death, many disease from CDC

Vital Events

Deaths

Births

Marriages

Divorces

Fetal Deaths (>28wk pregnancy)

National Vital Statistics System

Collects national birth and death statistics

• Vital and Health Statistics Series

• National Death Index

Limitations to mortality data

• Chronic illnesses

• Multiple causes of death

• Lack of standardization of diagnosis criteria

• Stigmas attached to certain diseases

• Completeness of records

• Changes in ICD codes over time

Deaths

Mortality data are almost totally complete because death are unlikely to go unrecorded

• Not allowed to die w/o death certificate

National Center for Health Statistic (NCHS) compiles and publishes national mortality rates

Death certificate data in the US include the following information:

• Demographic characteristics

• Date/place of death

• Cause of death

Data Recorded in Death Certificates

Demographic Characteristics

• Age

• Sex

• Race

Date & Place of death — hospital or elsewhere

• Cause of Death

• Immediate Causes

• Contributing Factors

Birth Statistics

Include live births and fetal deaths (>28wks = death certificates, <28wk = miscarriage)

Used to calculate birth rates

Helpful for understanding

• Birth defects

• Length of gestation

• Birth weight

• demographic background of mother

U.S. Bureau of the Census (happens every decade)

Provides data that can be used to define the denominator in rates

• Official estimates of total population size and subdivisions of the population by geographic area

Passive Surveillance

Based on data reported by healthcare provides

Commonly used for infectious diseases

Subjected to underreporting and incompleteness

Local outbreaks may be missed

Inexpensive

Limitation:

• Infected don’t go to doctor

• Providers don’t report completely

Active Surveillance

Field workers make periodic visits to clinics and hospitals to collect data on incident cases

Very useful if an outbreak is suspected or begun to keep track of the # of cases

Often more complete than passive surveillance

Expensive = requires more time

National Notifiable Diseases Surveillance System (NNDSS)

Physicians must report cases of certain diseases, known as reportable and notifiable diseases, to health authorities

Sentinel Surveillance

Involves collecting data from sample of reporting sites (sentinel sites)

• selected healthcare provides

• used by disease programs such as HIV and malaria

• Specific genetic diseases

Allows states to monitor trends using relatively small of info

Syndromic Surveillance

Using health-related data that precede diagnosis (signs & symptoms) and signal sufficient probability of a case or an outbreak to warrant further public health response

→ Uses clinical info about disease signs & symptoms before diagnosis is made

Often uses electronic data from hospital emergency rooms

Examples:

NYC - emergency dep chief-complaint data from ~44 hospitals

2002, systems had higher than usual diarrheal & vomiting symptoms (chief complaint)

Health department notified hospital emergency departments of possible outbreak

• Collected stool samples → several tested + for norovirus

Adverse Event Reporting System (AERS)

Vaccine Adverse Event Reporting System (VAERS)

adverse event — any favorable, unintended sign (abnormal lab finding), symptom, disease temporally associated with the use of a medicinal product, combination product, or medical device, whether or not considered related to the product

• Ex: Pacemaker, antidepressant, etc.

• Same for VAERS, but for adverse events reportable specifically attributable to receiving a vaccine

  • Parents can report autism as an adverse effect

  • Any healthcare provider and/or member of the public can submit report