Understanding the Role and Challenges of Public Health, Lecture notes of Public Health

Download Understanding the Role and Challenges of Public Health and more Lecture notes Public Health in PDF only on Docsity! Lecture 1: What is Public Health? Part 1: Introduction ● Public Health: the set of activities a society undertakes to monitor and improve the health of its collective membership ○ Three features ■ Preventing disease and injury ■ “Patient” is entire community, not individuals ■ “Provider” is society, not individual professionals ○ Differences from medicine ■ Often involve individual provider treating an individual patient with a “problem” ● Illness or disability ■ In public health, trying to prevent an issue for a whole population ● Healthcare measures have greatest impact for prevention of disease and premature mortality ○ Modification of personal health behavior Part 2: Relationship Between Public Health and Medical Care ● Imbalance between public health and medical care ○ Importance of public health dominates that of medical care system ○ However, we put our resources into medical system and not public health ■ $3.5 trillion expenditure on medical care annually ■ $50 billion dollars to the entire field of public health annually ● Five reasons for the imbalance ○ Economic interest cater to services for individuals not the public good ■ Public health is a public good ○ Special interest groups impacting policy ○ “Rule of Rescue” – current trauma first before abstract future benefits ■ People want to be taken care of when there is something seriously wrong with them in the immediate (illness, serious injury) ■ Less interested in doing something that will help their health in the future ○ Lack of appreciation for relative risks ■ Planes vs cars ○ Invisibility of public health ■ Desirable versus “selling public health” ■ When it works, public health is hard to see ● Measles and mumps ● Through vaccination public health has eliminated many diseases ● ■ Public health success translates into public health invisibility ● Public perception of public health ○ Benefits are abstract, deferred ○ Costs are tangible, immediate ○ Disease promotion Part 3: Mission of Public Health ● NAM: “fulfilling society's interests in assuring conditions that people can be healthy” ● Making society healthy with public health ○ Generate organized community effort ○ Address public interest in health ○ Apply scientific and technical knowledge to prevent disease and promote health ● 3 Core Functions: ○ Assessment of population health ■ Data collection on health status and various demographics of the population ● Statistical and epidemiological analysis on data ■ Dissemination of findings to public and public health professionals ○ Development of public health policies ■ Scientific knowledge base ■ Appreciate and employ use of political process ● Essential to making public health policy ○ Assure availability of needed services ■ Encourage appropriate action by public and private entities ■ Require actions through law or regulation ■ Provide direct service Part 4: Core Areas of Public health ● 5 core areas of public health: ○ Epidemiology ■ Concerned with analyzing and describing patterns of occurrence and determinants of diseases in human populations ■ Where a lot of analysis occurs (epidemiological analysis) ○ Biostatistics ■ Focus on development and application of statistical and mathematical methods to the design and analysis of public health problems and biomedical research ■ Statistics applied to public health ○ Environmental Health Sciences ■ Aims to protect human health from adverse environmental conditions ● Harmful practices and exposures in air, water, and food in the workplace, home, and ambient environments ● EX: obesity ○ More likely to be obese based on genetic conditions ● Alcohol and drug abuse, homelessness, HIV-aids ○ Economic interests ■ Often powerful economic interests hurt by public health regulations ● Alcohol distribution ● Tobacco companies ● Healthcare facilities, bars, etc ○ Can believe that regulations diminish their economic interests ■ Powerful economic interests translate into political lobbies ● Gun lobby effective in congress– encouraging legislators to not have gun control laws ■ Cost burden falls on different people than those who benefit ■ Politics of current costs for future abstract benefits ● Politics don’t have a timeline longer than next election ● Expenditures of public health occur while in office; however, the payoffs are not experienced until later ○ Morality issues in public health debates ■ Intensely felt positions that derive from a sense of moral or religious right norms ● EX: abortion, sex education in schools, HIV-aids prevention, gay marriage, stem cell research ○ Politics in science ■ Administrations often promote their own political agendas by interfering with science ● Withholding resources ○ HIV aids ● Tie resources to compliance with policy decisions ○ Many administrations have refused to provide financial support through USAID to promote programs that deal with birth control ● “Litmus tests” for high-level appointees ○ Candidates for supreme court, pushed by president on position on abortion ● “Stacking” review bodies with partisans ● Misrepresentation or suppression of scientific findings ○ Climate change Part 7: Summary QUESTIONS: 1. Public health focuses on populations, whereas medicine focuses on individuals. (T/F) 2. Which of the following health measures has the greatest potential for the prevention of disease and premature mortality in the U.S.? a. Group of answer choices b. Reduction of environmental pollutants c. Genetics d. Modification of personal health behavior e. Medical services 3. Which of the following had the greatest impact on average life expectancy in the US between 1900 and 2000? a. Group of answer choices b. Vaccines c. An improved medical care system d. Improved sanitation, housing, nutrition, and job safety 4. According to Professor Warner, public health is a "tough sell" because in many cases: a. the benefits are immediate b. the benefits are deferred c. the costs are immediate d. the costs are deferred 5. Most people lack a good understanding of public health because: a. Public health is no longer as necessary as it was in the past. b. The public health process is divorced from policy development c. The silent victories of public health translate into public health invisibility. 6. Which of the following is necessarily a goal of public health? a. To ensure that people have needed services b. To provide services directly to people 7. Epidemiology is part of what function of public health? a. Assessment b. Policy development c. Assurance d. Intervention 8. Which of the five core areas of public health is concerned with examining the health risks of exposure to BPA, a chemical used to make certain plastics? a. Epidemiology b. Biostatistics c. Environmental Health Sciences d. Health Behavior and Health Education e. Health Management and Policy Lecture 2: Population Health Population Health: Part 1 ● Concepts, Terminology, and perspectives: to understand differences and similarities of Health, Public Health & Population Health ● Key Measures of Population Health: infant mortality, life expectancy, mortality rates ○ How have they changed over time and why? ○ How does the US compare with other countries? ○ How does Population Health help to explain/understand trends over time, and thereby inform public health policy or interventions? ● How do we define the three types of health– all three intersect ○ Public Health: the set of activities a society undertakes to monitor and improve the health of its collective membership ■ Public health is multifaceted and includes three key domains” ● Assessment, policy, and assurance ■ More than medical care or medical practice ○ Health: ■ American Heritage Dictionary: The condition of an organism at a given time, soundless, especially of body or mind: freedom from disease or abnormality. ■ World Health Org: A state of complete physical, mental, and social well- being and not merely the absence of disease or infirmity ■ Multidimensional ● Focus on the individual ● Little or no quantifiable measurement ● Includes more than just physical well-being ○ Population Health: the health outcomes of a group of individuals, including the distribution of such outcomes within a group ■ Numerical concept involving collection of health data on our about individuals health, risk factors, and health outcomes that taken together provide an assessment of a population’s health ■ Involves measurement of health outcomes of population (not just individuals) ■ Involves measurement of risk factors or determinants of health outcomes ■ Includes looking at population averages and trends, and also examination of distributions of outcomes and risk factors (ie health disparities) Case Study: Health, Public Health, & Population Health ● Joe Smith is a UM student living in Markley. Over 2-3 days he develops a cough, fever, and malaise, and goes to the SHS for evaluation ○ Is this a health issue? ○ Multiple medical advances that spread over the sector had a big impact ■ Widespread use of antibiotics, development of fluid and electrolyte replacement therapy, safer blood transfusions ● 1960-1980: Mortality continued to decline significantly but reasons varied overtime ○ 1960s federal government instituted medicaid and other federal programs ■ Made medical services available to millions of people who previously had no insurance ■ By 2018 43% of all pregnancies and births in the US were covered by Medicaid ● Primarily impacted postneonatal mortality rates ○ 1970s breakthroughs in medical practice and technology and dissemination of practices ■ 40% decline in neonatal births ■ Decline in infant mortality slowed in mid 1980s but picked up in 1990s ○ 1990s development of pulmonary surfactant to treat respiratory distress syndrome in premature infants ■ Impact on neonatal mortality ○ 1990s reduction in deaths from Sudden Infant Death Syndrome (SIDS) ■ Following research showing lower incidence when babies sleep on back rather than stomach ○ 1990s wider dissemination of vaccines against major childhood illnesses ■ Diphtheria, tetanus, measles, polio and Haemophilus influenzae type B ● Infant mortality rates among selected OECD countries 1960-2014 ● Organization for Economic Co-operation and Development ○ 37 most economically advanced countries in the world ○ Ranking of US fell from 1960 to 2014 ○ 6 times worse than countries with lowest rates ○ US spends more on capita per healthcare than any other country in the OECD Population Health Part 3: Life Expectancy ● Life Expectancy at birth: the average number of years that newborn is expected to live if current mortality rates remain constant in the future ○ Mortality rates are constantly changing ○ Concept is slightly artificial but good for assessing overall health status of population ● Life expectancy at 65: the average number years that a 65 yo is expected to live if current mortality rates remain constant in the future ○ Can asses life expectancy for any age ○ Assumed that you have survived till 65, so previous years are not considered ○ Measure of risk factors pertaining to older people ● US Life Expectancy at Birth 1900-2015 ○ From 1900-2015 life expectancy at birth in US went up by more than 30 years ■ Increase of about ⅔ ■ Reduction in infant mortality was major contributing factor to great increase in life expectancy and many of same factors contributed to success ● Better sanitation, food, housing, and more access to medical care ○ Differences by sex in life expectancy ■ Changes in maternal mortality and related to cigarette smoking ● Maternal mortality rate ○ At start of 20th century, birth was a risky life event ○ Maternal mortality rate or # of mothers who died of pregnancy related problems or during childbirth was over 800/100000 live births (just under 1%) ○ 1920s maternal mortality started declining significantly ○ 1950 rate was less than 100/10000 ○ 2013 less than 20/100000 ○ Overall decline of 98% ■ Better sanitation, clean water, better nutrition, improved and more widely available medical practice, legalization of abortion (reducing deaths from septic and illegal abortions) ■ Contributing to increase in life expectancy gap between males and females during middle decades of 20th century ● Trends in Tobacco Use and Lung Cancer ○ Increase in cigarette smoking particularly among men ○ During and after WWI, but exploded during WWII ○ Women began to smoke in 60-70s ○ Men tend to smoke more cigarettes per day than women ○ Smoking is a major risk factor for heart disease, variety of cancers, and chronic lung disease ■ Lung disease have been among leading causes of death in 20th century ○ Overall increase in life expectancy during 20th century was more pronounced in women than men ■ Difference in patterns of smoking has been key factor in difference of male and female life expectancies ● Life Expectancy at Birth among 35 OECD Countries ○ Consistent pattern of expectancy at birth greater among females than males ○ US currently ranks near bottom for both males and females compared to other OECD countries ■ Spends more money per capita on healthcare than any other country in world ■ Major problem in health system ● US Life Expectancy at age 65 ○ Once survived to age 65 infant mortality rates do not play a role ○ From 1900 to 1970 female grew by 5 and male grew by only 1 ■ Due to tobacco and increase in smoking among men in early and middle 20th century ■ Single biggest contributor to gap between sexes ○ When smoking rates decline, the gap declines as well ● Life Expectancy at age 65 among 35 OECD countries– Males 2015 ○ Still widespread in less developed countries ○ Cancer death rates in men ■ Cigarette smoking is important cause for cancers and heart disease and lower respiratory disease ● Initial onset was earlier in men and peak was much higher, reflecting more widespread smoking among men than women ■ Stomach cancer ● Food preservation ■ Colon cancer is still a leading cause of cancer ● Declined a lot since mid 1980s ● Combination of more widespread screening – colonoscopy, and reduction of risk factors like smoking ● Also decline in women ● Heart Disease Death Rates ○ 1900-50: rise in heart disease death ■ Increase smoking, poor diet, less exercise, no Rx HTN and cholesterol; lack of therapy ○ 1950-present ■ Reduced smoking; rx for HTN & cholesterol; vastly improved therapies for those with heart disease; improved diet (?) ○ Heart disease is leading cause of death ○ Stroke among top 10 causes of death Lecture 3: Health Differences and Disparities Introduction ● Public health seeks to protect and improve the health of entire populations ● Differences in health outcomes and experiences ○ Some groups of people tend to be sicker and lead different lives than other people ● Characters in Unnatural Causes: Is inequality making us sick? ○ Louisville, types of jobs, work, where they live, where they buy groceries ○ Stressors: what they do, where they live, social identities Part 1: Foundational Terms in Public Health ● Words are powerful ● Race: a social grouping of people who have similar characteristics that are generally considered by society as forming a distinct group ○ Defines race a social construct ○ These physical characteristics do not have intrinsic biological meaning ○ Race has been partially characterized by physical similarities: skin color, facial features, or hair texture ■ Research shows two people of same race can have more genetic variation between them than people of different races ○ Shift/change over time in place ○ Race matters because racial classifications have health and social consequences ○ Office Management and Budget (OMB) creates racial groups used for census ■ Up until 1960 individuals were not able to choose their own racial category ■ 2000 could choose two or more race ■ Race can be dictated by social institutions ● Ethnicity: grouping based on “common descent and culture” and is a result of social processes ○ Social interactions with other groups highlight differences between groups ● Differences between race and ethnicity ○ Race classified by physical characteristics (skin color) ○ Ethnicity classified by cultural differences between groups (religious practices) ○ Social and economic advantages and disadvantages ● Socioeconomic status (SES): social standing or class of individual or group. It is often measured as a combination of education, income, and occupation ○ Reveals inequities and lack of resources, as well as issues related to power, privilege, or control ● Racism: racism is the belief that race is the primary determinant of human capacity and moral trait, and that there are inherent superiorities in a particular race(s) ○ Can be experienced ■ Interpersonally: language, body language, or other beliefs and actions held by individuals that are racially motivated ■ Structurally: society reinforces and fosters racial discrimination by reinforcing systems that in turn reinforces inequitable distribution of resources ■ Institutionally: racially discriminatory policies and practices carried out by the state or non-state groups (employer practices and jim crow laws) Part 2: Ways of Describing Health Differences ● Health is considered a fundamental right ○ The enjoyment of highest attainable standard of health is one of the fundamental rights of every human being without distinction of race, religion, political belief, economic or social condition – WHO, 1948 ● Health differences: a measurable difference in health conditions or deaths in one population compared with the general population ○ Difference in outcomes from elderly to general population ■ As people age they experience reduced morbidity than those in general population ○ Higher rate of arm injuries among tennis players versus general population ● Health disparity: a particular type of health difference that is closely linked with economic, social, or environmental disadvantage. Health disparities adversely affect groups of people who have systematically experienced greater social or economic obstacles to health ○ 20% of people without college degrees smoke compared to 7% of college graduates ● Over ⅓ of americans are obese ○ Differences in obesity rates for men and women and white and black people ● Considering the role of health behaviors is important ○ Focus on factors outside the individual that may lead to health behaviors ○ Focus on resources like time, money, or physical environment ● Social determinants of health ○ Our health is influenced by our social and physical environments ● Differences in social determinants of health are largely responsible for health disparities ● Economic stability affects health through resources to meet daily needs ○ Healthful foods ○ Housing ○ Medical care ● Neighborhood and physical (built) environment influence health ○ Housing quality and safety ○ Green space and walkability ○ Environmental pollution ● Education affects health through economic resources and health knowledge ○ Income ○ Employment ○ Health knowledge ○ Social resources ○ Stress ○ Healthy behaviors ● The stability and quality of one’s food influences health outcomes ○ Food security ○ Access to quality foods ○ Availability of healthy options ● Health is affected by one’s social and community context (social cohesion, family/friend support, civic participation, incarceration, experience of racism) ○ Limited economic opportunities ○ Residential segregation ○ Stress levels ○ Socially vulnerable communities more likely to be hurt by disaster events ● Health care system affects health outcomes ○ Access to healthcare ○ Provider and hospital availability ○ Quality of care ● Racism interacts with and shapes each social determinant of health ● Not everyone has the same opportunities to be healthy ○ Health disparities are unjust, preventable differences in ehealth ○ Health disparities based on race, economic status, and other social factors exist for all key population health measures ○ Health behaviors, stress, and (primarily) the social determinants of health underlie health disparities ○ Strive for highest possible standard for all ■ Eliminate disparities and achieve health equity Lecture 4: A Brief History of Public Health Part 1: Introduction ● Prehistoric humans learned how to avoid disease even before public health concerns ○ Learned to defecate downstream from living areas ○ Burry people away from the area ● Disease used to be thought of as “deserved” ● Enlightenment period brought about scientific evidence ○ Malaria or “bad air” in italian was viewed as one of the first disease whose cause was viewed to be something related to the environment as opposed to a punishment or skin ○ Lepers excluded from society in leprosy colonies ○ No explanation for how disease spread ● 14 century plague known as the black death brought humanity brink of distinction ○ Reduced world population by a 5th ● Plague killed nearly ½ of europe's population and took over 100 years to recover ○ Through trade routes ● Spread of disease was not just limited to european continent travelers along intercontinental trade routes carried disease across the ocean ○ European explorers brought smallpox to north america ○ Smallpox killed many more native americans than europeans Part 2: A brief history ● 17th Century more sophisticated approach to health ○ 1639 Massachusetts Bay Colony required birth and death registration ■ Resolution to prevent pollution was passed ■ Quarantine ships ● Leading causes of death in 18th century ○ Malaria, smallpox, and other infectious diseases ● 1793 epidemic of yellow fever in philly affected a large portion of population causing 10% of population to die ○ To help, US gove set up quarantine marine hospital ■ Deal with disease on board ships ○ Marine Hospital service act provided healthcare for merchant seaman ■ First healthcare insurance ● 19th century industrial revolution ○ Dangerous and toxic working conditions, overcrowding, lack of adequate sanitation, poor access to clean water, air pollution all contributed to emergence of chronic diseases ○ Need for better living and working conditions, improved sanitation efforts ○ John Snow ■ 1854 during cholera epidemic in london, mapped cholera cases in the city ● Discovered people who were infected all go their water from the broad street pump ● First case of modern day epidemiology ○ Lemeuel Shattuck completed report of the sanitary commission of massachusetts ■ Sanitary survey of the state ■ Recommendations for promotion of public and personal health ■ Considered beginning of modern era of public health ○ Control infectious disease ○ Monitor food and water safety ● United States Constitution ○ Preamble: promote general welfare ○ 10th amendment: fed does not have ultimate responsibility Part 2: The Legal Role for Government Involvement ● Most state constitutions require it to protect health and welfare of citizens ● Public Health Agency authority differs across the country ○ State have authority for their own public health ○ Assign responsibility to themselves since it is missing in US constitution ● EX: newborn screening for sickle cell disease ○ Testing newborns for fatal diseases ○ What is put on the panel for testing differs state by state ○ 1984 national recommendation for newborn sickle cell anemia testing across US ■ Took 30 years for entire Us to implement in 2014 ■ States differ in funding and priorities and can establish their own framework ○ Federal government still has influence ● Components of Public Health System ● 6 Main Areas of Population Health in Federal Government ○ Policy making ○ Financing ○ Public health protection ○ Collecting and dissemination of health delivery systems ○ Capacity building for population health ○ Direct management of services ● The US Congress is involved in public health in two ways ○ Commerce power ■ Interstate commerce applies to most goods ● Tobacco, medical devices, pharmaceuticals ○ Power to tax and spend ■ Taxes provides for general welfare of united states ○ Also funds major federal agencies that manage public health and state agencies ■ CDC ● Leading public health services for united states ● Housed under department of health and human services ● Focus on national concerns around health prevention and disease control ● Federal and state governments working together ○ 2009 H1N1 Influenza pandemic ■ 89 Million cases ■ 6 billion dollars ○ CDC worked with state and federal government to communicate about response ■ Distributed Public Health Emergency Response Fund to state and local jurisdiction based on population need, risk and other factors ● Then states in control of spending ○ Nebraska, contracted with nurses to distribute vaccine ○ Texas funded bilingual campaign Part 3: The Institutional Structure of the Public Health System ● State Tribal Local and Territorial Health Department (STLTs) ○ Limited in power and resources ○ Constitution grants states police power ■ Used by states to promote laws of general welfare of health and society ○ Examples of police power include laws authorizing: ■ Isolation and quarantine ■ Community vaccination ■ Licensure of medical professionals ■ Response to public health emergencies ● Bioterrorism ● Infectious disease outbreaks ● Local governments get authority from their respective states ○ Many public health actions are facilitated through local governments ○ Over 3000 local health departments ■ Considered foot soldiers of public health ■ Responsible for day to day public health activities ○ EX: Washtenaw County ■ Food service licensing and inspection ■ Dental clinics ■ Suicide prevention ■ Communicable disease clinics ■ School health services ● The Indian Health Service oversees health care for the 567 federally recognized tribal governments in the US ○ Vary in legal status ○ Sovereign nations maintaining government to government relationship ○ Federal government provides them with health services ● Interconnected network shaping public health system Part 4: Stakeholders and Interest Groups ● Department of Health and Human Services ○ Houses federal work in public health ○ Headed by a member of president's cabinet ● Centers for Disease Control and Prevention (CDC) ○ Responsible for infectious disease control ○ Conducts research ○ Produces health education materials ○ Trains the public health workforce ○ Collects data on nation’s health ○ Gives international public health aid ○ Focus: disease outbreak ■ Around globe to provide international health aid ● Food and Drug Administration (FDA) ○ Focus: health safety ○ Safety of manufactured foods ○ Safety of medical devices ○ Safety of vaccines ○ Each prescription drug is approved for human use by FDA ● National Institute for Health (NIH) ○ 28 institutes focusing on broad range of research ■ Cancer ■ Heart disease ■ Aging ■ Mental health, etc ○ 3 institutes consume 40% of NIH budget ■ National Cancer Institute ■ National Institute of Allergy and Infectious Disease ■ National Heart, Lung, & Blood Institute ● Federal Government also controls aspects of health insurance ● Center for Medicare and Medicaid Services (CMS) ○ Medicare– health insurance for elderly ■ Primarily federal responsibility ○ Medicaid– health insurance and nursing home care for the poor ■ Shared responsibility between federal and state governments ○ Now– epidemiology health services, CDC ■ Specialized individuals are trained to go into dangerous/difficult situations to understand ebola outbreak, where toxic spill could cause cancer in immunity ● Determine extent of disease ○ Early part of last century, rural sanitary services (examining outhouses) established first local health departments ■ People tried to understand what diseases were spreading in their communities ● Natural history of disease ○ Understanding biology underlying disease ○ Being able to figure out what diseases are quite severe and very fatal, versus which have silent onsets with chronic outcomes ○ Biology of smallpox ■ How it was transmitted from human to human ■ Knowledge translate into best public health in action as smallpox was eradicated in 70s ○ CDC has list of notifiable diseases ■ If hospital, individual, community sees one, notify CDC right away ○ Better understanding of if someone can develop immunity, harbor throughout lifetime, is it contagious, or a natural part of aging? ■ Knowing discrete information helps health behavior and health communication to keep people from getting susceptible moments ■ WWII soldiers keeping away from STDS ● Evaluate new and preventive intervention methods ○ FDA responsible for looking at evaluation of every drug in country and evaluating if it is safe for practice ○ Many other prevent and intervention methods that need epidemiological lens ■ See if they improve health and when in use do actually improve population health ○ 20th century gift to 21st century is vaccinations ■ Benefit from longer life, less diseases, children because of whole vaccination movement in 40s in 50s ■ 30s typhoid fever vaccine developed ● Public policy and regulatory decisions ○ Starts with assessment of public health ○ Policy cycle ■ Assessment of population health (epidemiology) ■ Assessment of potential interventions (epidemiology) ■ Policy choices ■ Policy implementation ● Then evaluated should give evidence that policy is working to improve people's health and reduce disease ■ Policy intervention Part 3: Endemic, Epidemic, and Pandemic ● Talk about occurrence of disease in population ○ Context being time and geography ● Endemic: the usual occurrence of disease within a given geographical area ○ What is endemic in Michigan will be different than in Florida, Costa Rica or Russia ● Epidemic: the occurrence of an infectious disease clearly in excess of normal expectancy ○ Above normal levels ■ Costa Rica: already has endemic, so high levels would be epidemic ■ Michigan: no cases, so a few outbreaks would be epidemic ● Pandemic: a worldwide epidemic affecting an exceptionally large high proportion of the global population ○ Across many countries and usually continents ● Departments of Health usually work with local clinics, hospitals, or other parts of health system to look at how much disease is regularly occurring (infectious, chronic, accidental) ○ Once baseline is established there can be levels of inquiry to understand endemic levels ■ Hospital discharge, mortality records, cancer registries, birth defect registries ■ If no local data, look at larger population data ● State, regional, etc ● 1918 Spanish Flu (pandemic influenza) ○ Killed millions of individuals worldwide ○ More than any flu predecessors ○ Define epidemic and pandemic peak in population ○ WHO created a whole signal staging, individuals in local, state, federal agencies know where we are in terms of pandemic alert system ● 2009 WHO signals global pandemic raising the alert level to Phase 6 ○ As cases of H1N1 started to move into US and other countries ■ Wave of information moved WHO alert system up to highest level ■ Southern Hemisphere seeing H1N1 flu on top of strains, northern hemisphere saw H1N1 strain in summer months ● Over 70 countries within 2-3 months reported cases ○ Many aspects of collecting information for WHO to make calls ● Global Surveillance of Communicable Diseases: Network of Networks Part 4: Outbreak Investigations ● Steps of outbreak investigations, how they collect information communities need in order to take action ● 10 Basic Steps ○ Preparing for field work ○ Establishing existence of outbreak ○ Verify diagnosis ○ Finding and identifying cases ○ Describing and orient data in terms of person, place and time ○ Develop hypotheses of how outbreak started ○ Evaluate truth of hypothesis ○ Refine hypotheses and carry out additional studies ○ Implement and control prevention measures ○ Communicate findings ● Establishing existence ○ Starts with understanding of how severe the outbreak is and weather or not an outbreak is really happening (or a few anomalies cases) ○ What figures into existence of outbreak ■ Understanding of severity of illness ■ Potential for spread ■ Political considerations ■ Public concern around it or pressure around getting to bottom ■ Decided based on drug you want to evaluate ■ Be as representative of population as possible ○ Study population randomized ■ Some new treatment ■ Some current treatment or placebo ○ Asses if treatment improved health outcome ■ Place weather or not they got disease and develop disease based on group ■ Compare risk of getting sick with drug versus placebo ○ Look at common chronic disease drugs ■ EX: high blood pressure ● Always clinical trials to find best blood pressure treatments ● Arhat (largest) 42000 individuals ○ Evaluate hypertension treatment ○ Stakeholders in large clinical trial ■ Public ■ Health professionals ■ Media ■ Investigators ■ Dissemination ● Cohort Studies ○ Sister to RCT ○ Follows group of individuals initially free of disease over time to answer what the effects are of a particular disease ■ Exposure, eating, how much fat, smoking, bpa in plastic, pesticides ○ Starts with individuals from population at large ■ 1000-10000 and evaluate if they have been exposed ■ Follow individuals over time to see if patients develop disease ■ EX: heart disease and cholesterol change ○ Assessment of disease state over time ■ Answer question what are effects of particular exposure ○ Exposures need to be clear, objective, and measurable ■ EX: smoked at least 100 cigarettes in a lifetime and do you smoke now? ● Used oral contraceptives for at least six consecutive months ● At noon meal restaurant “X” on august 10 2000 ○ Sources of exposure information ■ Interviews, medical records, lab reports, questionnaires, exams, environmental measures, vital records ■ Often used together for a single exposure read ○ Outcomes should also be clear, objective, and measurable ■ Physician diagnosis ■ Specified ICD codes in hospital discharge data ■ Cause of death on certificate ○ EX: nurses health study 1976 ■ Over 200,000 nurses questionnaires on regular bases around what they have been exposed to and what diseases they’ve developed ■ Cornerstones of understanding of risk factors associated with women's health ○ Advantages ■ Temporality (exposure of disease) ■ Efficient for rare or unusual exposures ■ Asses multiple outcomes from single exposure ■ Can estimate incidence (probability of developing disease in future) ○ Disadvantages ■ Expensive studies (millions of dollars) ■ Inefficient for studying rare diseases ■ Not good for disease that take a long time to develop ● Case control studies ○ Most frequently used study design ○ Participants selected on whether or not they are diseased ■ Those who are diseased are called cases ● Exposed? ● Not-exposed? ■ Those who do not have disease are called controls ● Exposed? ● Not exposed? ■ Use data into 2 x 2 table looking at if case had exposure vs not, and control exposure vs not ○ The odds ratio: ○ Advantages ■ Good for studying rare diseases ● Recruit from rare disease clinics themselves ■ Can use smaller sample sizes ■ Cost/time effective when using previously collected exposures ■ Collected exposures from cohort studies ○ Disadvantages ■ Can’t calculate incidence ■ Selecting appropriate controls with same change to develop disease can be challenging ● Like the case in all same ways but did not get disease ■ Subject to selection bias and recall bias ● Human nature to have disease, more willing to be a part of study, cases show up who are not the same in terms of the control ● When asked a question, if you have disease whether or not exposure caused it, more likely to say yes than control ● Cross-sectional study ○ Gives rise to many prevalence estimates ○ Simultaneously asses disease and exposure in an individual ○ Study of prevalences and their interrelationship ○ Occurs at single point in time (no follow up) ○ Measures of association: ■ Prevalence odds ratio ■ Prevalence ratio ○ Advantages ■ Faster and less expensive than cohort studies ■ Often done to get information to apply to the population at large (source population) ■ Get good estimates of prevalence of many exposures and outcomes at same time ○ Disadvantage ■ Temporarily most often not know (but sometimes) ■ Can’t capture information in the change in risk factors or disease over time ■ Not good for rare diseases ■ Not good for rare exposures ○ Two measures of association in cross-sectional studies Lecture 7: Biostatistics Part 1: What is Biostatistics? ● Confidence interval: random interval that includes the true value of a parameter in a give population of samples ○ 95% confidence interval: in 95/100 of bars, population parameter is included ○ Gives us a measure of the effect ■ Important in terms of if it is practically or clinically significant ● Critically evaluating study for practical vs statistical significance ○ What is the estimate of the effect and is it relevant? ○ What is the practical significance of the findings? Part 5: Bias ● Need to consider to critically evaluate studies ● Bias: result or measurement that differs systematically from the population result or measurement of interest ● Can occur at any stage of research: design, collection, analysis, publication ● Independent of sample size and statistical significance ● Examples of bias ○ Selection bias ○ Healthy user ■ Type of sampling bias where kinds of subjects that voluntarily enroll in clinical trial or study and follow experimental regimen are generally not representative of the general population ■ People who take vitamins more likely to be health ● Or is it that people who are more likely to take vitamins are more likely to be healthy already ○ Recall ■ Why we like longitudinal studies more preferred than cross-sectional ■ A systematic error caused by differences in the accuracy or completeness of past information ○ Publication ■ Studies with positive or interesting findings are published more often than studies with negative or non-positive findings ■ EX: makers of antidepressants did not publish many non-positive results ● Only focus on studies where treatment seems effective ● New England Journal of Medicine ○ 95% of positive were publish ○ 14% of questionable or negative publications ○ Confounding ● Critically evaluate for bias ○ Is there anything that differs systematically from the population of interest? ○ Are the results valid or is there some bias? Part 6: Correlation and Causation ● Correlation: degree of a relationship between two variables or quantities ○ 2012 new england journal of medicine: correlation between per capita chocolate consumption and number of Nobel prize winners in 23 countries ○ Correlation without causation ■ Socioeconomic status, education, etc ○ Association between variables ○ Association does not indicate one caused the other ● When critically evaluating ○ Are two things in question associated? ○ Does one thing actually cause the other? ○ Is the causation a correct conclusion based on study design and analysis? Part 7: Conclusion ● Is the sample representative of the population? ● Is the sample of adequate size to provide strong results? ● Is there practical and statistical significance? ● Sisystemainc difference that could create bias? ● Association or causation? Lecture 8: Infectious Diseases and Public Health Part 1: Historical Explanations for Disease ● 1800s ○ Miasma theory dominant explanation for disease ■ Miasma: defined by Sanitarians as foul and poisonous emanations from filthy water, soil, and air ■ Dated back to roman times ■ Malaria, bad air ■ In general thought improving cleanliness and contamination would get rid of pathogens in the air, bad gasses ○ Florence nightingale ■ Reformer showed improved sanitary conditions in military hospitals and barracks could reduce mortality ■ Developed standards and practices of nursing, and statistical approaches to show effects of interventions ■ Mortality dropped from 42.7% to 2.2% after arrival ● Miasma theory not correct, but interventions still worked ○ Mid 1800s ■ Ideas of contagions and germ theory taking off ■ Put together ideas of contagiousness and idea that microorganisms could cause disease ■ 1546 Girolamo Fracastoro → seed like entities ■ 1840 Jacob Henle embraced unpopular microorganisms theory ○ John Snow was first to use maps to track disease back to its source ■ Cholera thought was bad air or miasma ■ 1854 outbreak, Snow realized that it was contagious and spread through water sources ● Map showed that Soho outbreak was likely due to public water pump on Broad Street ● Convince officials to remove handles of pump and outbreak subsided ● Spatial patterns mapped to show outbreaks, Snow first epidemiologist ● After Dr. Semmelweis implemented chlorine handwashing, puerperal fever mortality dropped ○ 1840s Holmes & Semmelweis found out that fever was likely transmitted by doctors to their patients ○ Did not wash hands in between births, autopsy, etc ○ Mortality in ward where med students performed autopsies was higher than in ward where they didn't ○ Semmelweis instituted hand washing policy ● Infectious diseases are no longer leading cause of death in the US ● Chronic disease is now major cause ● Infectious is 2nd leading cause of death worldwide ● Infectious burden falls heavily on lower and middle income/developing countries ○ Low/middle income countries top 3 ○ Upper/middle among top 5 ● Several factors are leading to (re)emergence of infectious diseases ○ Urbanization and crowding ○ Increasing mobility ■ Travel ○ Increasing contact between humans and environment ○ Increasing pollutants ○ Potential for bioterror ○ Effects of global warmings ■ Disease vectors ● Infectious disease outbreaks seem to be increasing but are they? ○ Population size increasing ○ Disease surveillance, etc increased ● Emerging infections have been linked to contact with animals ○ HIV ○ Influenza ○ Ebola Part 3: nature of infectious diseases ● Pathogens fall into five categories ○ Bacteria ○ Viruses ○ Fungi ○ Parasites ○ Prions ○ Other: algee ● Example caused by bacteria: TB ○ Coinfection with HIV ○ Increase in drug resistance make it difficult to treat ● Example caused by parasite: malaria ○ Many interventions involve prevention of mosquito bites, nets, standing water, bug spray, etc ○ Not yet active vaccine ● Example caused by a virus: influenza (flu) ○ Flu vaccine Part 4: Transmission ● Transmission can occur through direct contact ○ Person to person occurs when pathogen transferred by contact from infected person to another person without contaminated intermediate object ■ Coughs, sex, touch ● Indirect contact/transmission ○ Indirect involves transfer of pathogen by contact with contaminated intermediate inanimate object ■ Food, toy, water ■ Broad st pump ○ Or contaminated vector ■ Mosquito, tick, mice ■ Malaria ● 4 possible outcomes of exposure ○ No infection ○ Carrier, no illness ○ Subclinical ○ Clinical infection ● Infectious process has 3 periods: incubation, latent, and infectious ○ Period where infected individual doesn’t show symptoms but can pass disease ○ Periods can vary between diseases and within diseases ■ Rabies onset and be a week or a year after exposure Part 5: Investigating and preventing outbreaks ● Endemic: habitual presence (or usual occurrence of a disease within a given geographic area) ● Epidemic: occurrence of a disease clearly in excess of normal expectancy in given region ● Pandemic: worldwide epidemic affecting an exceptionally high proportion of global population ● Why investigate outbreaks ○ Prevent additional cases, need to identify and eliminate source of problem Lecture 10: Introduction to Chronic Disease Part 1: What is Chronic Disease? ● What is Chronic Disease ○ Duration: chronic versus acute ■ CDC: a condition that lasts 1 year or more and requires ongoing medical attention or limits daily livor or both (ADLS) ■ National Center for Health Statistics: A disease lasting three months or longer ■ WHO: they are of long duration and generally slow progression ○ Usually term chronic disease is meant to distinguish such conditions from acute infectious disease and injuries ○ WHO: they are not passed from person to person, they are noncommunicable ○ But many infections are chronic and some cause cancer or increase risk of certain cancers: ■ HPV → chronic viral hepatitis (HBV and HCV) ■ HIV → Epstein Barr virus, helicobacter pylori and schistosoma haematobium ■ 20% of all cancers are ideologically related to chronic diseases ○ Commonly includes major fatal chronic diseases ■ CVD (heart/stroke) ■ Cancer ■ Diabetes ■ Chronic respiratory disease ■ Alzheimers ■ Chronic kidney disease ● Often terminology does not include common sometimes nonfatal chronic conditions that are debilitating and costly, such as mental illness, migraines, oral diseases, and arthritis ○ Alternative broader approach: a chronic disease is something that is continuing or occuring again and a gain for a long time Part 2: What is the Impact of Chronic Disease: ● Impact of chronic disease ○ 1900s leading cause of death dominated by infectious disease ○ 2000s leading cause of death dominated by chronic disease ■ Overall death rates declined over 20th century ■ Absolute rates of death have declined ○ Surveys vs screening for chronic diseases: methods measurement matter ■ Surveys ● Less expensive; include large number of participants ● Rely on what people know about their own health ● Chronic conditions can be asymptomatic ○ Hypertension, diabetes, etc ■ Medical screening ● Yields more comprehensive and accurate results ● Direct measurement of chronic disease in a population ● Asymptomatic diseases can be detected ● NHANES conducted by CDC on regular basis ○ Chronic disease is leading cause of death in US ○ Chronic disease is common among adults ■ 12% of US adults have 5 or more chronic conditions ○ Prevalence of multiple diseases (more than 2) chronic diseases is higher among older adults, and has been stable in recent years ○ Women 18-64 report more CDS ■ Unknown if this is because women seek more healthcare than men ■ Confounding variable ○ Non White racial/ethnic groups have historically had less access to insurance/services hence less likely to be diagnosed? ■ Unlikely that differences are accurate ■ Less likely to have been diagnosed ● Diagnosed diabetes ○ Non Hispanic whites have a lower prevalence of disease than other racial and ethnic categories ○ US adults with diabetes: 30.2 million (12.2% of US adults) ○ Almost a quarter of US adults with diabetes don’t know they have it ■ Similar to HTN CKD and high cholesterol ● Almost 30% of US adults had HTN in 2015-2016 ○ Highly correlated with age and somewhat greater among men ○ The percent of adults with HYTN who were unaware has declined significantly for all age groups ○ 50% who are aware of high blood pressure do not have it under control ● People with more chronic conditions are more likely to utilize all forms of medical services ● Americans with 5 or more chronic conditions make up 12 % of population but account for 41% of all healthcare spending ● Per-person health care spending increases dramatically among those with chronic conditions ○ 14x greater for those with chronic conditions ● Chronic conditions increase health care expenditures regardless of insurance type ● ADLs are adversely impacted by CDS ○ Activities of Daily Living ■ Bath, dress, eat, walk up stairs, etc ○ Adults are more likely to experience limitations when have CDs (65+) Part 3: Chronic Disease Part 3: Common Misunderstandings about CD ● 10 Common misunderstandings ○ CDs affect mostly high income countries ■ Reality: of CD deaths are in low and middle income countries⅘ ○ Low or middle income countries should focus on control of infectious disease before CDs ■ Double burden requires double response ■ While IDs are often high, CDs are high and or growing particularly in urban settings ○ CDs mainly affect rich people ■ In all but least developed countries, poor people are much more likely to develop CDs than wealthy people and more likely to die as a result ○ CDs mainly affect old people ■ Almost half of CD deaths in world occur in people under age of 70 ■ Contribute to large fraction of years of potential life loss ○ CDs affect primarily men ■ CDs, including heart disease affect men and women almost equally ○ CDs are result of poor personal choices/unhealthy lifestyles (alcohol, smoking, food, lifestyle) ■ Children and or poor often have limited choice related to environment, diet, passive smoke exposure, living conditions, access to education and health care