CHN FINALS

Common causative agents

• Viruses

• Bacteria

• Fungi

• Parasites

Epidemiologic Triangle

explains how disease occurs through the interaction of the agent, host, and environment.

Chain of Infection

explains how diseases spread from one source to another. Infection happens when all links are connected.

Infectious agent

microorganism that causes disease.

Reservoir

where the pathogen lives, such as humans, animals, soil, or water.

Portal of exit

how the pathogen leaves the body, such as respiratory secretions, blood, feces, or urine.

Mode of transmission

how the pathogen spreads, such as droplets, contact, air, food, water, or vectors.

Portal of entry

how the pathogen enters another person, such as mouth, nose, broken skin, or mucous membranes.

Susceptible host

a person likely to be infected, such as infants, elderly people, immunocompromised individuals, or unvaccinated people.

How to break the chain

• Handwashing

• Vaccination

• Isolation

• PPE

• Proper sanitation

RESPIRATORY DISEASES

diseases affect the lungs and breathing. They are commonly transmitted through the air when an infected person coughs, sneezes, or talks.

National Tuberculosis Control Program

aims to prevent and control tuberculosis in the Philippines. It focuses on early detection, free diagnosis, free treatment, and treatment completion.

DOTS

Directly Observed Treatment, Short-course

Pulmonary Tuberculosis

caused by Mycobacterium tuberculosis. It mainly affects the lungs and spreads through airborne droplets.

Pneumonia

is an infection of the lungs that may be caused by bacteria or viruses. It can cause inflammation and fluid buildup in the lungs.

Signs and symptoms: productive cough, shortness of breath, rapid breathing, chest pain, and crackles on auscultation.

Pneumonia Mangement

antibiotics, oxygen therapy, hydration, and antipyretics.

Influenza

viral respiratory infection that spreads easily in crowded communities.

Signs and symptoms: sudden fever, dry cough, sore throat, body aches, fatigue, and headache.

VECTOR-BORNE DISEASES

illnesses transmitted by vectors, commonly mosquitoes. In the Philippines, common examples include dengue, malaria, filariasis, and Japanese encephalitis.

Dengue

viral infection transmitted by the bite of an infected Aedes aegypti mosquito. It is a major public health concern in the Philippines.

Febrile

PHASES OF DENGUE

high fever, headache, body pain, nausea, vomiting, and rash may appear.

Critical

PHASES OF DENGUE

fever may go down, but the patient may worsen; watch for bleeding, abdominal pain, persistent vomiting, and shock.

Recovery

PHASES OF DENGUE

appetite returns, vital signs stabilize, and urination increases.

Malaria

caused by Plasmodium parasites and transmitted by the bite of an infected female Anopheles mosquito.

Main symptoms include cyclical fever, chills, rigors, and sweating

FOOD AND WATERBORNE DISEASES

occur after consuming contaminated food or water. They are commonly linked to poor sanitation, unsafe drinking water, and improper food handling.

Food and Waterborne Disease Prevention and Control Program

reduces illness and death from diarrhea, typhoid fever, cholera, and similar diseases

WASH

Water, Sanitation, and Hygiene.

Water

safe and clean drinking water

Sanitation

proper toilets and waste disposal.

Hygiene

handwashing and clean practices.

Cholera

caused by Vibrio cholerae and spreads through contaminated food or water.

Signs and symptoms: profuse watery diarrhea, rice-water stool, vomiting, muscle cramps, and severe dehydration.

Cholera Management

doxycycline or azithromycin

Typhoid Fever

aused by Salmonella typhi and spreads through contaminated food or water.

Signs and symptoms: sustained high fever, abdominal pain, weakness, constipation or diarrhea, and rose spots.

Gold standard test for typhoid fever

blood culture

Hepatitis A

spreads through the fecal-oral route and may cause jaundice, dark urine, fatigue, nausea, and right upper quadrant pain.

Acute gastroenteritis

may cause diarrhea, vomiting, abdominal cramps, fever, and dehydration.

National Immunization Program

provides free routine vaccines to infants, children, pregnant women, and selected groups. Its goal is to protect Filipinos from vaccine-preventable diseases.

Measles

highly contagious viral disease transmitted through airborne droplets.

Signs and symptoms: high fever, cough, runny nose, red eyes, Koplik spots, and blotchy rash.

Mumps

causes fever, headache, and painful parotid gland swelling; complications include orchitis and hearing impairment.

Rubella

causes mild fever, fine pink rash, and lymph node swelling; infection during pregnancy may cause congenital syndrome.

Varicella

causes itchy vesicular rash and fever; it spreads through airborne droplets and direct contact with blister fluid.

Rabies

through animal bites and is fatal once symptoms appear; prevention requires wound washing and post-exposure prophylaxis.

SEXUALLY TRANSMITTED INFECTIONS

passed through sexual contact involving the mouth, anus, vagina, or penis. Some STIs may have symptoms, while others may be asymptomatic.

National AIDS/STI Prevention and Control Program

Aims to reduce HIV and STI transmission.

Linked to National AIDS/STI Prevention and Control Program

RA 8504 and RA 11166

HIV/AIDS

attacks the immune system, especially CD4 T-cells. If untreated, it can progress further.

Modes of transmission: sexual contact, blood exposure, sharing needles, and mother-to-child transmission.

HIV management

antiretroviral therapy

Syphilis

caused by Treponema pallidum and may progress through primary, secondary, latent, and tertiary stages.

Gonorrhea

Caused by Neisseria gonorrhoeae and may cause dysuria and purulent discharge.

NEGLECTED TROPICAL DISEASES

mostly affect poor communities in tropical and subtropical areas. Examples include schistosomiasis, soil-transmitted helminthiasis, and leprosy.

Lack of funding and research

Schistosomiasis

caused by blood flukes. It is transmitted when larvae from infected freshwater snails penetrate the skin during contact with contaminated water.

Soil-Transmitted Helminthiasis

refers to intestinal worm infections acquired from contaminated soil.

Leprosy

caused by Mycobacterium leprae. It affects the skin, nerves, eyes, and nasal lining.

Signs and symptoms: skin lesions, numbness, loss of sensation, and muscle weakness.

Treatment for leprosy

multidrug therapy

Emerging and re-emerging infectious diseases

are diseases that are newly appearing or increasing again in a population.

COVID-19

caused by SARS-CoV-2 and spreads through droplets, airborne particles, and contaminated surfaces.

Common signs and symptoms: fever, cough, sore throat, fatigue, and loss of taste or smell.

SARS

caused by SARS-CoV-1 and may cause high fever, chills, malaise, myalgia, headache, and diarrhea.

MERS

linked to zoonotic transmission, especially camels, and has a higher mortality rate.

Mpox

spreads through close contact, respiratory droplets, or contaminated materials and may cause fever, lymphadenopathy, and rash.

Non-communicable diseases

Chronic diseases that are not passed from person to person. They develop because of a combination of genetic, physiological, environmental, and behavioral factors.

Agent

harmful insults such as tobacco smoke, excessive glucose, unhealthy food, or physical stressors.

Host

the person’s characteristics such as age, genetics, ethnicity, and body condition

Environment

surroundings that promote unhealthy lifestyles, such as sedentary living, availability of ultraprocessed foods, and urban areas that discourage walking.

Non-modifiable factors

cannot be changed. These include age, genetics, and ethnicity.

Modifiable factors

can be changed. These include smoking, alcohol use, unhealthy diet, and physical inactivity.

Behavioral Risk Factors

1. Tobacco use

2. Physical inactivity

3. Unhealthy diet

4. Harmful use of alcohol

Galaw Pilipinas

national calisthenics program in the Philippines that promotes physical activity for all ages.

Children

active play and bone-strengthening activities

Adults

150-300 minutes of moderate-intensity aerobic activity per week

Elderly

balance and flexibility exercises to prevent falls

1/2 plate

glow foods such as fruits and vegetables

1/4 plate

go foods such as rice and carbohydrates

1/4 plate

grow foods such as protein-rich food

Republic Act 9211

also known as the Tobacco Regulation Act.

Brief Tobacco Intervention

which includes asking, advising, assessing, assisting, and arranging follow-up.

Cardiovascular Diseases

Include hypertension and coronary heart disease. Management includes medications and lifestyle changes.

Diabetes Mellitus

focuses on blood glucose monitoring and prevention of complications. Foot care is important because poor circulation and nerve damage may lead to wounds, ulcers, and amputation.

Chronic Respiratory Diseases

include COPD and asthma. Management includes avoiding triggers and proper use of inhalers.

Philippine Package of Essential NCD Interventions (PhilPEN)

It is used to manage NCDs at the primary care level. starts with screening protocols using the DOH Risk Assessment Form for adults aged 20 and above.

Adolescent-Friendly Health Facilities

provide a non-judgmental space for youth to seek help. Programs focus on nutrition, teenage pregnancy prevention, substance abuse prevention, screen time management, and physical literacy

Substance use

consumption of psychoactive substances in a socially accepted or medical way, such as drinking wine during celebration or taking prescribed pain medication.

Substance misuse

using a drug for the wrong purpose or not following medical/legal guidelines, such as using another person’s prescription or taking higher doses than prescribed.

Substance abuse

maladaptive pattern of substance use that causes significant impairment or distress.

Substance dependence/addiction

most severe form, involving psychological and physical need for the substance.

Brain Disease Model

explains addiction as a chronic brain disease. Chronic substance use changes the brain’s structure and function.

mesolimbic dopamine pathway

Drugs affect the brain’s reward system which is:

prefrontal cortex

when affected it can weakens decision making, impulse control, and emotional regulation.

Methamphetamine hydrochloride or Shabu

Most abused illegal drug

Marijuana

second most common substance

Inhalants

often used by street-dwelling populations and minors because they are cheap and accessible

Individual level

genetics, mental health, personal behavior

Interpersonal level

Family dynamics, peer pressure

Community level

drug availability, lack of recreational spaces, poverty

Societal level

cultural attitudes, policies, and social conditions

Community-Based Treatment Approach

it is based on the idea that recovery is more effective when it happens within the person’s natural environment rather than isolation.

Continuum of Care

support from prevention and early intervention up to treatment, aftercare, and social reintegration.

Human Rights-Based Approach

people who use drugs must be treated with dignity and compassion. Services should be voluntary, non-discriminatory, and evidencebased.

Integration

drug recovery services should be included in the primary health care system so physical and mental health needs are treated together.

Community Health Nurse

first line of defense in screening, education, and referral

ASSIST tool

Alcohol, Smoking, and Substance Involvement Screening Test

Outpatient Care

or low-to-moderate risk users. They can stay at home, continue working, and attend counseling.