CHN 3RD YEAR MOD 3

NATIONAL DEMOGRAPHIC HEALTH SURVEY

As the years pass by, it is still evident that a small percentage would resort to having their delivery at home, wherein the majority would also prefer having their delivery at a health facility.

73.4 years

LIFE EXPECTANCY
was the average life expectancy at birth globally in 2019.

NATIONAL HEALTH SITUATION

• Ischemic heart disease (Top 1)

• Lower respiratory infections (Top 2)

EPIDEMIOLOGY

• Definition: Study of the distribution and determinants of health-related states/events in populations.

• Focus: Population level (global, national, community, school, neighborhood) → not individuals.

•Scope:

o Covers not only diseases but also other health-related states/events.

o Looks at distribution (frequency, patterns).

o Identifies determinants (risk factors, causes).

• Application: Used for prevention and control of health problems.

FREQUENCY

EPIDEMIOLOGY
• Refers to number of health events (e.g., pneumonia cases, diabetes cases).

• Can be expressed as ratios or rates to compare across populations.

PATTERN

EPIDEMIOLOGY

• Refers to occurrence of health events by:

o Time: annual, seasonal, weekly, daily, hourly, etc.

o Place: geographic (urban vs. rural), specific locations (schools, workplaces).

o Person: demographic & risk factors: age, sex, marital status, socioeconomic status, behaviors, environmental exposures.

DESCRIPTIVE EPIDEMIOLOGY

Characterizing health events by time, place, person

Analytic epidemiology

compares groups with different disease rates to identify links with determinants.

• Purpose → evidence for public health control & prevention.

EPIDEMIOLOGIC METHODS

• Used to study communicable & noncommunicable diseases and other health events.

EVOLUTION OF EPIDEMIOLOGY

• Originally: Focused only on epidemics of communicable diseases.

• Now expanded: Includes

o Chronic diseases (NCDs)

o Maternal & child health

o Occupational health

o Environmental health

o Other health-related events

Sporadic

Disease occurs infrequently and irregularly

Rare cases like tetanus

Endemic

Constant Presence/usual prevalence of a disease in a geographic area

Ex. Malaria in some tropical region

Hyperendemic

Persistent, high levels of disease occurence

Higher than usual, but steady

Ex. High TB rates in some country

Epidemic

Sudden increase in cases above what is normally expected in a population/area
Ex. Flu epidemic in a city

Outbreak

Same as epidemic but usually smaller to a geographic area

Ex. Food poisoning in school

Cluster

Grouping of cases in time and place, maybe more than expected (even if exact expected number is unknown)

Ex. Cancer cluster in a factory

Pandemic

Epidemic spread across several continents/countries affecting many people
ex. COVID-19, 2009 H1N1 Influenza

NATURAL HISTORY OF DISEASE

Shows progression from sub-clinical changes → clinical signs/symptoms → resolution or death

Exposure

Pathogen enters a susceptible host.

Invasion & Multiplication

Pathogen invades tissue/organ; body starts immune response

Infection

Pathogen acknowledged by host; may be symptomatic or asymptomatic

Latent Period

Time between exposure and infection.

o Pathogen is present but no signs/symptoms.

Incubation Period

Time between exposure and onset of symptoms. o Host may already be infectious at any stage depending on the pathogen.

CRUDE BIRTH RATE (CBR)

• Measures how fast people are added to a population through births.

GENERAL FERTILITY RATE (GFR)

• Measures the number of live births per 1,000 women of reproductive age (15-49 yrs old) in a given year.

POPULATION PYRAMID

A graphical representation of the age-sex composition of a population.

MORTALITY INDICATORS

Mortality indicators measure how omen deaths occur in a population and are essential for assessing and improving community health.

CRUDE DEATH RATE (CDR)

Represents the overall death rate in a population during a given time period.

SPECIFIC DATE RATE (SDR)

• Measures the death rate within a specific subgroup of the population.

PROPORTIONATE MORTALITY RATE (PMR)

• Shows the proportion (%) of deaths due to a specific cause or age group compared to all deaths

MATERNAL MORTALITY RATE (PMR)

• Maternal Mortality Ratio (MM Ratio):

Often only considers direct maternal deaths, while MMR (rate) can include both direct + indirect.

INFANT MORTALITY RATE (IMR)

• Measures the risk of dying before age 1 in a population.

MORBIDITY INDICATORS

Illness, disease, injury, or disability (not being healthy). Can be felt (subjective, like pain) or measured (objective, like high BP)

INCIDENCE RATE (IR

• Incidence = new cases → shows risk of getting the disease

PREVALENCE RATE (PR)

Prevalence = all cases (new + existing)