What are the recommendations for immunoprophylaxis (prevention of disease through vaccines or immunoglobulins)?

Immunoprophylaxis Recommendations

Immunoprophylaxis should be implemented through a structured approach prioritizing healthcare workers' protection against occupational exposures (hepatitis B, influenza, measles, mumps, rubella, varicella), followed by age-based and risk-based vaccination for all adults, with special considerations for immunocompromised individuals who require modified schedules and inactivated vaccines only. 1

Healthcare Workers: Strongly Recommended Vaccinations

Healthcare workers face unique occupational risks requiring mandatory immunization against specific pathogens:

• Hepatitis B vaccination is required for all healthcare workers with potential blood or body fluid exposure, administered intramuscularly in the deltoid muscle during professional training before patient contact 1
• Post-vaccination serologic testing (anti-HBs) should be performed 1-2 months after completing the 3-dose series for workers at ongoing risk of needlestick injuries 1
• Influenza vaccination is strongly recommended annually for all healthcare workers to prevent transmission to vulnerable patients 1
• MMR (measles, mumps, rubella) vaccination is mandatory for all healthcare workers without documented immunity 1
• Varicella vaccination is required for healthcare workers without evidence of immunity 1

Post-Exposure Prophylaxis Protocol

When unvaccinated healthcare workers experience percutaneous or mucosal exposure to HBsAg-positive blood, administer HBIG within 24 hours (preferably) and initiate the hepatitis B vaccine series immediately 1. For exposures occurring more than 7 days after the incident, HBIG effectiveness becomes uncertain 1.

Universal Adult Immunizations

All adults, including healthcare workers, require baseline protection:

• Tetanus-diphtheria (Td) booster every 10 years following primary 3-dose series (doses separated by 4-6 weeks for first two doses, third dose 6-12 months after second) 1
• Pneumococcal vaccination for all adults ≥65 years: single dose of PCV20 for those without prior pneumococcal conjugate vaccine 2

Risk-Based Pneumococcal Vaccination (Ages 19-64)

Administer PCV20 to adults aged 19-64 with any of the following conditions 1, 2:

• Chronic cardiovascular disease (congestive heart failure, cardiomyopathies)
• Chronic pulmonary disease (COPD, emphysema—not asthma)
• Diabetes mellitus
• Alcoholism
• Chronic liver disease (cirrhosis)
• Cerebrospinal fluid leaks
• Functional or anatomic asplenia (sickle cell disease, splenectomy)
• Immunocompromising conditions (HIV, leukemia, lymphoma, Hodgkin's disease, multiple myeloma, chronic renal failure, nephrotic syndrome, organ/bone marrow transplantation, immunosuppressive chemotherapy including long-term systemic corticosteroids) 1

Special Pneumococcal Protocols

For immunocompromised adults who previously received only PCV13: administer PPSV23 at least 8 weeks later, followed by a second PPSV23 dose at least 5 years after the first PPSV23 2

For hematopoietic stem cell transplant recipients: administer 3 doses of PCV20 4 weeks apart starting 3-6 months post-transplant, followed by a fourth dose at least 6 months after the third dose 2

Immunocompromised Individuals: Critical Modifications

General Principles

Killed or inactivated vaccines are safe for immunocompromised individuals and should be administered per standard schedules 1. However, immune responses may be suboptimal, potentially requiring higher doses or more frequent boosters 1.

Live virus or live bacterial vaccines are contraindicated in immunocompromised persons, with specific exceptions detailed below 1.

HIV-Infected Individuals: Specific Algorithm

For asymptomatic HIV-infected persons without severe immunosuppression:

• MMR vaccine is recommended 1
• Inactivated poliovirus vaccine (IPV) only—never oral poliovirus vaccine (OPV) 1
• Annual influenza vaccine (for ages ≥6 months) 1
• Pneumococcal vaccine (for ages ≥2 years) 1

For symptomatic HIV-infected persons without severe immunosuppression:

• MMR administration should be considered on a case-by-case basis 1

For HIV-infected persons with severe immunosuppression:

• Measles vaccine is contraindicated 1
• All other inactivated vaccines remain indicated 1

Travel Immunizations for HIV-Infected Persons

Live vaccines are generally avoided, with these exceptions 1:

• Measles vaccine for nonimmune persons without severe immunosuppression 1
• Varicella vaccine for asymptomatic, nonimmunosuppressed children 1
• Yellow fever vaccine may be offered to asymptomatic HIV-infected travelers who cannot avoid exposure, with informed consent about uncertain safety and efficacy 1

Use inactivated vaccines instead of live alternatives:

• Inactivated parenteral typhoid vaccine (not oral live-attenuated) 1
• Inactivated poliovirus vaccine (contraindicated: oral poliovirus vaccine) 1

Hepatitis A Prophylaxis

Post-Exposure Prophylaxis

For persons ≥12 months exposed to hepatitis A, administer hepatitis A vaccine as soon as possible within 2 weeks of exposure 1. For adults >40 years, providers may also administer immune globulin based on risk assessment 1.

Pre-Exposure Prophylaxis for International Travelers

Infants aged 6-11 months traveling internationally: administer hepatitis A vaccine before departure (this dose does not count toward the routine 2-dose series, which begins at 12 months) 1

Infants <6 months: administer immune globulin 0.1 mL/kg for travel up to 1 month; 0.2 mL/kg for travel up to 2 months; repeat 0.2 mL/kg every 2 months for travel ≥2 months 1

Passive Immunization Indications

Intravenous immunoglobulin is indicated for:

• Children with congenital or acquired immunodeficiency (including HIV) who have ≥2 serious bacterial infections (bacteremia, meningitis, pneumonia) within 1 year 1
• Measles-susceptible, severely immunosuppressed persons anticipating travel to measles-endemic countries 1

Oral penicillin prophylaxis (125 mg twice daily) is recommended for:

• Infants and young children with sickle cell disease beginning before 4 months of age 1
• Children with functional or anatomic asplenia, particularly those <2 years or receiving intensive chemotherapy who cannot respond to polysaccharide vaccines 1

Implementation Requirements

Documentation and Catch-Up Programs

Maintain comprehensive immunization records for each individual documenting disease history, vaccination history, and all immunizing agents administered 1. Healthcare facilities must implement catch-up vaccination programs for existing employees alongside policies ensuring newly hired workers receive necessary vaccinations 1.

Work Restrictions Post-Exposure

Healthcare workers not immune to vaccine-preventable diseases require postexposure work restrictions ranging from limiting contact with high-risk patients to complete duty exclusion 1.

Common Pitfall to Avoid

Do not routinely test asymptomatic healthcare workers for HIV before administering live virus vaccines 1. Testing is unnecessary and creates barriers to timely immunization.

Pneumococcal and influenza vaccines can be administered simultaneously at different anatomical sites during the same visit 2, improving compliance without compromising efficacy.