2025 – PAGE 343 – VACCINES, IMMUNIZATIONS AND CONTRAINDICATIONS

PREGNANCY AND IMMUNIZATION

Your role here is likely limited (leave it to the OB) and thus this is a low-yield topic. Currently, Tdap and inactivated influenza are the only ones recommended in pregnancy. Live vaccines are contraindicated, HPV vaccine is not recommended, and the use of various other vaccines depends on the situation. Again, low-yield topic, but guidelines are available here: www.pbrlinks.com/PREG1

POSTEXPOSURE PROPHYLAXIS

The following discusses postexposure prophylaxis for N. meningitidis, Haemophilus influenzae B, pertussis, hepatitis A, hepatitis B, varicella, and measles.

• RIFAMPIN PROPHYLAXIS: It’s used for both meningitidis(AKA meningococcus) and H. flu prophylaxis. Once prophylaxis is started, reddish-orange urine and tears may be noted.
  • MENINGITIDIS: Only one case of exposure is required to start prophylaxis in contacts.
  • INFLUENZAE B: For school and daycare contacts, TWO documented cases of invasive H. flu are required. So, if you are presented with a question about the index case at a school, the classroom contacts are not required to get prophylaxis until a second case is confirmed. If the immunization status is unknown for someone receiving chemoprophylaxis, also give the Hib vaccination. For household contacts, only ONE case is needed to start prophylaxis for everyone in the household if:
    • The household has a child younger than 4 years who is incompletely immunized
    • The household has a child younger than 12 months who has not completed the primary Hib series
    • The household has an immunocompromised child, regardless of Hib vaccination status
• PERTUSSIS: Give a macrolide to all household contacts and all exposed people who are at high risk (including infants, pregnant women in their third trimester, those with a pre-existing illness like asthma, and those with contact with infants and pregnant women.
  • PEARL: Give azithromycin for kids < 6 weeks of age due to concern for pyloric stenosis. For those > 6 weeks of age, give erythromycin. If the patient is unimmunized, also give the vaccine.
• HEPATITIS A: Give Hep A vaccine to all contacts if healthy and > 12 months old. If < 12 months old, give immunoglobulin. If immunocompromised and > 12 months old, give both Hep A vaccine and immunoglobulin.
• HEPATITIS B NEEDLE STICK:
  • IMMUNIZED: If the patient’s immunity status is known to be up to date by titers, no prophylaxis is needed.
  • UNCERTAIN IMMUNIZATION STATUS: CHECK for antibody. If negative, give the immunoglobulin (HBIG) and also start the full vaccination series. If the antibody is positive, do nothing.
  • UNIMMUNIZED: Give the immunoglobulin (HBIG) and also start the full vaccination series.
• PEARL/SHORTCUT: CHECK FOR IMMUNITY. Then either do nothing, or give both the immunoglobulin (HBIG) and the Hepatitis B dose #1 of 3.
• VARICELLA (VZV): Give the immunoglobulin to individuals who are at high risk for complications, including those who are pregnant, immunocompromised, and some infants.