Midwife Licensure Exam Community & Public Health — Communicable Disease Control & ImmunizationSummary

The three levels of prevention provide a systematic framework for nursing intervention at different points in the natural history of disease. **Primary prevention** acts to prevent disease occurrence before infection—examples include health education on hygiene, immunization (the gold standard of primary prevention–specific protection), provision of safe water, nutrition support, and vector control measures. **Secondary prevention** focuses on early detection and prompt treatment to arrest disease progression and reduce complications; examples include case-finding through symptom screening, contact tracing, and early diagnosis with immediate anti-TB therapy (DOTS) or antimalarial treatment. **Tertiary prevention** aims to limit disability and support rehabilitation, such as managing TB drug side effects, counseling on complications, and facilitating social reintegration of persons with communicable diseases. In the Philippines' healthcare delivery context, resource constraints mean primary prevention through immunization and health education often achieves the greatest population impact per peso spent.

**Active immunity** occurs when the body's own immune system (B cells and T cells) produces antibodies and memory cells in response to antigen exposure; this provides **long-lasting, durable protection** lasting years to lifetime. Active immunity develops through two routes: **(1) natural active immunity**—from having the disease itself (e.g., natural measles infection confers lifelong immunity), and **(2) artificial active immunity**—from vaccination with antigen (live attenuated, inactivated, or subunit vaccine). **Passive immunity** involves receiving preformed antibodies from an external source, providing **immediate protection but short duration** (weeks to months) because the body does not generate memory cells. Passive immunity occurs naturally through **maternal antibodies** transferred across the placenta (especially IgG, protecting infants until ~6 months) or through breast milk (IgA provides mucosal immunity). **Artificial passive immunity** is conferred by administration of immunoglobulins or antisera (e.g., tetanus immunoglobulin [TIG] for post-exposure prophylaxis, hepatitis B immunoglobulin [HBIG] for newborns of HBsAg-positive mothers). **Herd immunity** (community immunity) is achieved when a sufficient proportion of a population is immune (typically 85–95% depending on disease transmissibility); this reduces transmission chain and indirectly protects even unvaccinated individuals.

The Philippine EPI was **launched in 1976** under DOH leadership to reduce morbidity and mortality from vaccine-preventable diseases. Legal mandates include **Presidential Decree 996** (1976) establishing compulsory basic immunization for children under 8 years, and **RA 10152 (Mandatory Infants and Children Health Immunization Act of 2011)** which strengthened the program by mandating free routine immunization for all infants and children and explicitly including Hepatitis B vaccine within 24 hours of birth as a neonatal protective measure. The EPI originally targeted **six diseases** (the classic target diseases: TB, diphtheria, pertussis, tetanus, poliomyelitis, and measles) and has progressively expanded to include **Hepatitis B, Haemophilus influenzae type b (Hib), pneumococcal conjugate vaccine (PCV), and others**. The **routine infant schedule** follows precise ages and intervals: **BCG and monovalent Hepatitis B at birth**; **Pentavalent (DPT-HepB-Hib), OPV, and PCV at 6, 10, and 14 weeks** (minimum 4-week intervals); **IPV at 14 weeks and 9 months**; **Measles-containing vaccine (MCV1) at 9 months**, and **MMR (MCV2) at 12 months**. A **Fully Immunized Child (FIC)** has received BCG (1 dose), OPV (3 doses), Pentavalent (3 doses), and measles-containing vaccine (at least 1 dose) **before reaching 12 months of age**. A **Completely Immunized Child (CIC)** completes the same antigens but by **12–23 months of age**. Coverage targets (≥95%) are monitored quarterly and used to guide resource allocation to low-performing municipalities.

Correct vaccine administration is essential to ensure immunogenicity (vaccine effectiveness) and minimize adverse events. Each vaccine has a **specific route and dose** that must not be substituted: **BCG is intradermal only** (0.05 mL for infants, 0.1 mL for children ≥1 year), given over the **deltoid muscle of the right upper arm**, with success confirmed by formation of a **wheal** immediately after injection; a subsequent papule and scar at 6–12 weeks indicate successful take (BCG scar). **Measles-containing vaccines (MCV1/AMV at 9 months and MCV2/MMR at 12 months) are subcutaneous** (0.5 mL) in the **outer upper arm**. **DPT, Pentavalent, PCV, and Hepatitis B are intramuscular** (0.5 mL) in the **vastus lateralis** (anterolateral thigh) for infants and young children; older children may receive in the deltoid. **OPV is oral** (2–3 drops into the mouth), given after ensuring the child has no vomiting/diarrhea in the past hour. The nurse must use **aseptic technique, sterile needle and syringe, and reconstitute vaccines as per manufacturer instructions**. Multiple vaccines given simultaneously require **different syringes and injection sites** at least 2.5 cm apart (to prevent cross-reactivity and allow identification of site-specific adverse effects if they occur). Vaccination records must be **accurately documented** in the health center register, child's health card (pink book / immunization card), and FHSIS reports.

The **cold chain** is the unbroken system of cold storage and transport maintaining vaccines within the safe temperature range (usually +2°C to +8°C for routine vaccines) from manufacture through administration. A broken cold chain renders vaccines ineffective and creates false sense of immunity. **At the rural health unit (RHU) / health center level, refrigerators must maintain +2°C to +8°C**; **at regional and provincial levels, freezers maintain −15°C to −25°C** for storing OPV and measles vaccine stocks. **Heat sensitivity varies by vaccine: OPV is the MOST heat-sensitive, followed by measles and BCG**; these should be stored in the **coldest part of the refrigerator** (usually the bottom shelf). **Freeze-sensitive vaccines (DPT, Hepatitis B, Td, Pentavalent, PCV) must NEVER be frozen**—freezing denatures the toxoid component and reduces potency; frozen freeze-sensitive vaccines are identified by the **shake test** (vigorous shaking produces particles/flocculation, indicating freeze damage). **FEFO (First Expiry, First Out)** governs stock rotation to prevent vaccine wastage from expiration. The **Vaccine Vial Monitor (VVM)** is a heat-sensitive label on each vial showing cumulative heat exposure through color change; when the color matches or darkens beyond the discard mark, the vaccine must be discarded even if not expired. The nurse must **never expose vaccines to direct sunlight**, use **ice packs in cooler boxes during transport**, and **document temperature logs daily** to detect and troubleshoot cold chain breaks promptly.

**True contraindications to vaccination are rare and must be distinguished from false contraindications** (common misconceptions that delay immunization). A **true contraindication** exists when the risk of vaccine adverse event exceeds the benefit. **BCG is contraindicated in a child with clinical AIDS or symptomatic HIV disease** (CD4 <200/µL equivalent) because BCG is live and may disseminate; however, **BCG is safe for asymptomatic HIV-infected children**. **Live vaccines (MMR, OPV if still used, varicella) are contraindicated in severely immunocompromised children** (e.g., during cancer chemotherapy, high-dose corticosteroids). **Severe allergic reaction (anaphylaxis) to a vaccine component** is an absolute contraindication to further doses of that vaccine. **Severe adverse event following immunization (AEFI) from a previous dose**—such as convulsions or shock occurring within 3 days of DPT—warrants withholding that vaccine in future; however, **mild adverse effects (fever, soreness, mild rash) are not contraindications**. **Immunization MUST NOT be delayed for minor illnesses**—a child with mild cough, common cold, low-grade fever, or mild diarrhoea is safe to vaccinate; delaying vaccines for such minor reasons increases missed opportunities and lowers coverage. **Maternal fever, diarrhea, or infectious disease in other family members are NOT contraindications**. The nurse must counsel families that **pain, swelling, redness at injection site, mild fever, and irritability within 48 hours are normal and not dangerous**, and that **benefits of immunization far outweigh these mild effects**.

Tuberculosis (TB) remains a significant public health burden in the Philippines, with both pulmonary and extrapulmonary forms. The **National TB Control Program (NTP)** employs the **DOTS (Directly Observed Treatment, Short-course)** strategy, consisting of **five essential elements**: **(1) Political commitment with sustained government financing** for TB programs and drugs; **(2) Case detection through quality-assured bacteriology**, now using **Xpert MTB/RIF (GeneXpert)** as the primary diagnostic test—rapid, reliable, and detects rifampicin resistance in a single procedure—supplemented by **Direct Sputum Smear Microscopy (DSSM)** for treatment monitoring; **(3) Standardized treatment regimen with direct observation**, meaning a **health worker or identified treatment partner watches the patient swallow every dose of anti-TB medication**—this directly observed therapy (DOT) ensures adherence and prevents drug resistance; **(4) Uninterrupted supply of quality-assured first-line anti-TB drugs** (isoniazid [H], rifampicin [R], pyrazinamide [Z], ethambutol [E], streptomycin [S]); and **(5) Standardized recording and reporting system** tracking treatment outcomes (cure, completion, failure, death, lost to follow-up) for program monitoring. **Treatment has two phases: intensive phase (~2 months of HRZE or HRES for susceptible TB) and continuation phase (~4 months of HR or RE)**. **Category I treatment** (for new TB cases) is typically **2HRZE/4HR** (2 months intensive HRZE, then 4 months continuation HR). **Category II treatment** (for previously treated cases: relapse, treatment failure, lost to follow-up) is more complex, often **2HRZES/1HRZE/5HRE**, adding streptomycin in the intensive phase. **Drug-resistant TB (MDR-TB resistant to H and R, XDR-TB resistant to fluoroquinolones) requires specialized management** under the **Programmatic Management of Drug-Resistant TB (PMDT)**, with longer duration and second-line drugs.

The nurse's role in TB control extends across the treatment continuum. During **diagnosis and initiation**, the nurse facilitates **sputum specimen collection** (spot–morning or spot–spot pattern, total 3 samples) and supports **Xpert MTB/RIF testing**; counsels on diagnosis and treatment importance; and initiates **directly observed therapy (DOT)**. The nurse **identifies a reliable treatment partner** (family member, community health volunteer) to ensure DOT compliance on days when the nurse cannot observe directly. During **continuation of treatment**, the nurse **directly observes every dose** (not just spot checks), monitors for **adverse effects** (hepatotoxicity, optic neuritis from ethambutol, ototoxicity from streptomycin, peripheral neuropathy from INH—managed with pyridoxine), counsels on adherence despite lack of symptoms after 2 weeks, and manages comorbidities (diabetes, HIV) that impair cure. The nurse conducts **contact tracing**: identifies all household members, workplace contacts, and other close contacts of the TB patient; screens contacts for TB symptoms; arranges **chest X-ray or Xpert MTB/RIF for symptomatic contacts**; and initiates **TB preventive therapy (TPT) or isoniazid preventive therapy (IPT)** for close contacts without active TB (especially children <5 years and HIV-positive contacts). The nurse teaches **cough etiquette** (covering mouth when coughing), **sputum disposal** (spitting into safe container), **adequate ventilation** in the home, and **nutrition/rest** to support recovery. The nurse documents **treatment outcomes** accurately in the TB register and FHSIS reports, essential for NTP monitoring and accountability.

The **Philippine Integrated Disease Surveillance and Response (PIDSR)** system is the official mechanism for detecting and responding to communicable diseases of public health significance. Certain diseases are **legally notifiable**, meaning healthcare providers **must report them** to the health authority within a specified timeframe, triggering epidemiological investigation and control measures. **Immediately/urgently notifiable diseases (within 24 hours)** are diseases of high epidemic potential or eradication targets, including **acute flaccid paralysis (AFP; polio surveillance), measles, neonatal tetanus, cholera, meningococcal meningitis, dengue with warning signs/dengue hemorrhagic fever, rabies, plague, and yellow fever**. **Weekly notifiable diseases** (reported every Friday) include **dengue (uncomplicated), typhoid fever, TB, acute respiratory infection (ARI) in children <5, diarrhea in children <5, malaria, and others**. The **nurse's responsibility** is to: **(1) recognize notifiable diseases** in patients presenting to the health center; **(2) promptly report** to the supervising physician/health officer within the required timeframe; **(3) complete the case investigation form** accurately, documenting demographics, symptoms, onset, laboratory findings, and contacts; **(4) initiate case management** (isolation, treatment, contact tracing) as per national guidelines; and **(5) maintain confidentiality** while ensuring public health action. **Failure to report** is a breach of public health law and professional responsibility under RA 9173.

**Dengue** is an arboviral disease transmitted by the **Aedes aegypti mosquito** (and *Aedes albopictus*), a **daytime-biting mosquito** that rests indoors and breeds in **clean, stagnant water** (flower pots, water containers, discarded tires, coconut shells) around homes and communities. There are **four dengue serotypes (DENV 1, 2, 3, 4)**; infection with one serotype confers **lifelong immunity to that serotype only**, but a subsequent infection with a different serotype carries **increased risk of severe dengue (dengue hemorrhagic fever, dengue shock syndrome)** due to antibody-dependent enhancement. The **DOH 4-S Strategy Against Dengue** includes: **(1) Search and destroy**—actively identify and eliminate mosquito breeding sites in communities through environmental sanitation (emptying water containers, draining stagnant water, cleaning yards); **(2) Self-protection**—individual and family measures including application of **mosquito repellents (DEET-containing products), wearing long sleeves and pants especially during dawn and dusk, using screens on windows, using bed nets** (though dengue is day-biting, nets prevent evening/night biting Aedes); **(3) Seek early consultation**—patient and family education to recognize **warning signs of severe dengue** (severe abdominal pain, persistent vomiting, bleeding manifestations, unusual lethargy/restlessness) and seek immediate medical care for fever that persists >3 days or shows warning signs; and **(4) Support fogging/spraying**—community acceptance of **space spraying (fogging) during dengue outbreaks**, limited to hotspot areas to kill adult mosquitoes in flight, though this is a short-term measure and environmental cleanup remains the cornerstone. **Nursing role** includes community education, surveillance of suspected cases, assisting in case investigation (identifying breeding sites in patient's home), promoting community cleanup, and counseling families of dengue patients on hydration, rest, and danger signs warranting hospitalization.

Beyond the EPI six diseases and dengue, the Philippines faces additional communicable diseases requiring dedicated control programs aligned with international targets: **Malaria** remains endemic in specific provinces (Mindanao, Palawan, and parts of Eastern Visayas); transmitted by the **Anopheles mosquito** (night-biting, breeds in dirty/shaded water—distinguishing it from day-biting Aedes); control focuses on **long-lasting insecticidal nets (LLINs)**, prompt diagnosis via **RDT (rapid diagnostic test) or microscopy**, and artemisinin-based combination therapy (ACT). **Schistosomiasis (infection by *Schistosoma japonicum*)** is endemic in parts of the Visayas and Mindanao, with the **Oncomelania** snail as intermediate host; control includes **praziquantel mass drug administration, snail control, and health education on water safety** (avoiding contaminated rivers/streams). **Filariasis (lymphatic filariasis)** is targeted for elimination through **annual mass drug administration (MDA) with albendazole + diethylcarbamazine (DEC), vector control, and morbidity management**. **Hansen's disease (leprosy)** elimination programs target **multidrug therapy (MDT), early case detection, and rehabilitation**. **Rabies** (post-exposure prophylaxis emphasizing wound care, rabies immunoglobulin [RIG], and rabies vaccine series) remains a concern given loose dog populations. The nurse in community settings must **understand the epidemiology and endemic zones** of these diseases within their assigned barangay/municipality to guide health education and recognize suspect cases for referral.