NCLEX Review Guide: Adult Health - Immune System & Immunizations

Types of Immunity

• Active immunity occurs when the body produces its own antibodies in response to antigens through natural infection or vaccination. This provides long-lasting protection that can last years to a lifetime.
• Passive immunity involves receiving pre-formed antibodies from another source (maternal antibodies, immunoglobulins). This provides immediate but temporary protection lasting weeks to months.
• Natural immunity develops through exposure to actual pathogens, while artificial immunity is acquired through medical interventions like vaccines.

Routine Adult Vaccines

• Tdap/Td: Tetanus, diphtheria, pertussis booster every 10 years; pregnant women need Tdap during each pregnancy (27-36 weeks). Adults who haven't received Tdap should get one dose followed by Td boosters.
• Influenza: Annual vaccination for all adults ≥6 months unless contraindicated. Live attenuated vaccine (nasal) contraindicated in immunocompromised patients and pregnant women.
• Pneumococcal: PCV13 followed by PPSV23 for adults ≥65 years and high-risk adults 19-64 years. Space vaccines 8 weeks apart when both are indicated.
• Shingles (Zoster): Recombinant zoster vaccine (Shingrix) for adults ≥50 years, given as 2-dose series 2-6 months apart, even if previous shingles infection.

Immunocompromised Patients

• Live vaccines are contraindicated in severely immunocompromised patients including those with HIV (CD4 <200), active cancer receiving chemotherapy, or taking immunosuppressive medications.
• Inactivated vaccines are generally safe but may have reduced effectiveness in immunocompromised patients. Consider checking antibody titers to assess response.
• Household contacts of immunocompromised patients should receive inactivated influenza vaccine, not live attenuated nasal vaccine.

Pregnancy Considerations

• Live vaccines contraindicated during pregnancy including MMR, varicella, and live attenuated influenza vaccine. Women should avoid pregnancy for 4 weeks after receiving live vaccines.
• Recommended in pregnancy: Tdap (27-36 weeks each pregnancy), inactivated influenza vaccine, and COVID-19 vaccines provide passive immunity to newborn.
• Hepatitis B vaccine is safe during pregnancy if indicated for high-risk women.

Administration Guidelines

1. Verify patient identity and vaccine orders, check expiration dates and storage requirements
2. Assess for contraindications and allergies, particularly severe allergic reactions to previous doses
3. Use appropriate needle size: 1-1.5 inch for deltoid in adults, 22-25 gauge needle
4. Administer at 90-degree angle into deltoid muscle, aspirate is not necessary for vaccines
5. Document vaccine name, lot number, expiration date, administration site, and patient education provided

Common Side Effects & Management

• Local reactions (pain, redness, swelling at injection site) are most common and typically resolve within 24-48 hours. Apply cool compress and recommend acetaminophen or ibuprofen for discomfort.
• Systemic reactions may include low-grade fever, fatigue, and muscle aches, especially with live vaccines. These usually occur within 24 hours and resolve quickly.
• Serious adverse reactions are rare but include severe allergic reactions (anaphylaxis), shoulder injury, and syncope. Report to VAERS (Vaccine Adverse Event Reporting System).

Frequently Missed Concepts