Ask the Experts: All Questions

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Results (1317)

Recommendations vary among adults depending upon age, pneumococcal vaccination history (including PCV13, PCV15, PCV20, and PPSV23), and pneumococcal vaccine products available:

  • Adults age 19 or older with diabetes and no history of receiving any PCV20 or other pneumococcal vaccination as an adult should receive either PCV20 alone or a series of PCV15 followed in one year by PPSV23. No further doses are recommended.
  • People with diabetes who are age 19 through 64 and have already received one dose of PPSV23 may receive either one dose of PCV20 or PCV15 alone one year after the dose of PPSV23; no further doses of PPSV23 are recommended.
  • People with diabetes turning 65 who received PCV13 and PPSV23 before age 65, should receive either one dose of PCV20 or PPSV23. PCV20 should be given at least 5 years after the last pneumococcal vaccination. If using PPSV23, it should be given at least 5 years after the last dose of PPSV23 and at least one year after the last PCV.
  • People with diabetes who have already received PCV13 and have received a PPSV23 vaccination since turning 65 are not routinely recommended to receive any additional doses of pneumococcal vaccine. They have the option to receive a dose of PCV20 at least 5 years after their most recent pneumococcal vaccination on the basis of shared clinical decision-making, based upon their risk of pneumococcal disease and desire for additional protection.
Last reviewed: April 5, 2024

In clinical trials, the vast majority of infants had no side effects detected after nirsevimab administration. The most common side effects noted during the clinical trials of nirsevimab were rash occurring within 2 weeks after injection (seen in 0.9% of nirsevimab recipients versus 0.6% of placebo recipients) and injection site reactions (including redness, pain, swelling) occurring within 7 days after injection (0.3% of nirsevimab recipients versus 0% of placebo recipients). See the product package insert for more details: www.accessdata.fda.gov/drugsatfda_docs/label/2023/761328s000lbl.pdf.

Last reviewed: January 22, 2024

Yes. IG may be given any time before or after inactivated vaccines like HepA. However, the antibodies in IG may interfere with the effectiveness of certain live-virus vaccines, such as measles, mumps, and rubella (MMR) and varicella vaccines. CDC recommends waiting at least 6 months from the date of IG administration before administering MMR and varicella vaccines.

Last reviewed: June 25, 2023

Transmission of varicella vaccine virus is rare. However, if a pregnant or immunosuppressed household contact of a vaccinated person is known to be susceptible to varicella, and if the vaccinee develops a rash 7 to 21 days following vaccination, it is prudent that they avoid prolonged close contact with the susceptible person until the rash resolves.

Last reviewed: May 16, 2023

People with cancer need to be protected from influenza, and they can and should receive inactivated or recombinant influenza vaccine (but not live nasal spray vaccine [FluMist]) even if they are immunosuppressed. Cancer patients and survivors are at higher risk for complications from influenza, including hospitalization and death. Here is a helpful CDC web page on cancer and influenza for patients: www.cdc.gov/cancer/flu.

Last reviewed: September 10, 2023

The recommended schedule for the primary series given to an unvaccinated person is dose 1 now, dose 2 in 4 weeks, and dose 3 in 6 to 12 months. Tdap should replace at least 1 dose of Td, preferably between 27 and 36 weeks’ gestation to maximize the maternal antibody response and passive antibody transfer to the infant.

Last reviewed: March 31, 2022

Yes. The DTaP in the Pentacel can be counted. Although Pentacel is licensed as a 4-dose series and this may represent a fifth dose of Pentacel (in which case it would be off-label use), the dose of DTaP counts as the fifth dose of DTaP.

Last reviewed: December 28, 2022

Based on the weight and dosage provided (40 lbs and 15 mg/week), the child is currently receiving more than 0.4 mg/kg/week of methotrexate. This meets the Infectious Disease Society of America (IDSA) definition of high-level immunosuppression. Administration of both varicella and MMR vaccines are contraindicated until such time as the methotrexate dosage can be reduced. The 2013 IDSA definition of low-level immunosuppression for methotrexate is a dosage of less than 0.4 mg/kg/week. For additional details, see the 2013 IDSA Clinical Practice Guideline for Vaccination of the Immunocompromised Host: cid.oxfordjournals.org/content/early/2013/11/26/cid.cit684.full.pdf.

As a general rule, whenever feasible, it is recommended that non-live and live vaccines be administered 2 or more weeks before initiating immunosuppressive medications include human immune mediators like interleukins and colony-stimulating factors, immune modulators, and medicines like tumor necrosis factor-alpha inhibitors and anti-B cell agents. See CDC General Best Practice Guidelines for Immunization section on altered immunocompetence: www.cdc.gov/vaccines/hcp/acip-recs/general-recs/immunocompetence.html.

Last reviewed: June 19, 2023

The dosage depends on the schedule and manufacturer of the vaccine that you are using. For children 11 through 15 years of age, the 2-dose Recombivax HB volume is 1.0 mL. Otherwise, the 3-dose schedule of Recombivax HB or Engerix B is 0.5 mL through age 19 years. Heplisav-B, the 2-dose HepB vaccine given with a 4-week interval between 0.5 mL doses, is licensed for adolescents and adults beginning at age 18 years. Immunize.org offers a handy resource with charts detailing the correct dosages and schedules for monovalent HepB and HepA vaccines and combination products that include HepA and HepB vaccines. Go to www.immunize.org/catg.d/p2081.pdf.

Last reviewed: July 21, 2023

Shingrix has been shown to be immunogenic when given by the subcutaneous route. A dose erroneously given by this route does not need to be repeated.

Last reviewed: March 9, 2022

Several studies have documented the safety of measles and mumps vaccine (which are grown in chick embryo tissue culture) in children with severe egg allergy. Neither the American Academy of Pediatrics nor ACIP consider egg allergy as a contraindication to MMR vaccine. ACIP recommends routine vaccination of egg-allergic children without the use of special protocols or desensitization procedures.

Last reviewed: June 19, 2023

All foreign-born people (including immigrants, refugees, asylum seekers, and internationally adopted children) born in Asia, the Pacific Islands, Africa, and other regions with high or intermediate endemicity of HBV infection should be tested for HBsAg, regardless of vaccination status. Initiating HepB vaccination of immigrant children should not be delayed while awaiting HBsAg test results: you may draw blood for testing then administer the first dose of vaccine at the same visit. All people found to be HBsAg-positive should have ongoing medical management by a physician knowledgeable about hepatitis B and its complications.

Last reviewed: July 21, 2023

A person who is not moderately or severely immunocompromised and has only ever received a single dose of Novavax COVID-19 vaccine may receive a single dose of any licensed or authorized COVID-19 (2023–2024 Formula) vaccine, including Novavax.

Last reviewed: March 19, 2024

Adverse reactions occurring after administration of nirsevimab alone should be reported to MedWatch online (www.fda.gov/medwatch), by fax, by mail, or by contacting FDA at 1-800-FDA-1088.

Adverse reactions occurring after the coadministration of nirsevimab with a vaccine should be reported to the Vaccine Adverse Event Reporting System (VAERS) https://vaers.hhs.gov, and reports should specify that the patient received nirsevimab on the VAERS form.

Last reviewed: January 22, 2024

Yes. ACIP looked into this issue and included related information in its recommendations published in MMWR on February 22, 2013 (www.cdc.gov/mmwr/preview/mmwrhtml/mm6207a4.htm). ACIP reviewed available data on birth statistics and found that among those in the U.S. who have more than one pregnancy, a very small percentage (2.5%) have an interval of 12 months or less between births. The majority of people who have two pregnancies have an interval of 13 months or more between births. Approximately 5% of mothers have four or more pregnancies. ACIP concluded that (1) the interval between subsequent pregnancies is likely to be longer than is the persistence of maternal anti-pertussis antibodies, (2) most mothers would receive only 2 doses of Tdap, and (3) a small proportion of mothers would receive 4 or more doses.

A theoretical risk exists for severe local reactions (e.g., Arthus reactions, whole limb swelling) for pregnant people who have multiple, closely spaced pregnancies. However, the frequency of side effects depends on the vaccine’s antigen content and product formulation, as well as on preexisting maternal antibody levels related to the interval since the last dose and the number of doses received. The risk for severe adverse events has likely been reduced with current vaccine formulations (including Tdap), which contain lower doses of tetanus toxoid than did older vaccine formulations. ACIP believes the potential benefit of preventing pertussis morbidity and mortality in infants outweighs the theoretical concerns of possible severe adverse events in mothers.

Last reviewed: March 31, 2022

Inactivated influenza vaccine or recombinant influenza vaccine should be administered beginning at least 6 months after bone marrow transplant and annually thereafter for the life of the patient. A dose of vaccine can be given as early as 4 months after transplant, but a second dose should be considered in this situation. A second dose is recommended routinely for all children younger than 9 years receiving influenza vaccine for the first time.

Last reviewed: September 10, 2023

An 8-month-old is likely to have residual passive varicella antibody from his or her mother. The vaccine probably will have no effect, and no action is necessary. The dose should not be counted, and the child should be revaccinated on schedule at 12 through 15 months of age.

Last reviewed: May 16, 2023

Please see details of the recommendations for the use of IG for the prevention of hepatitis A provided in Table 4 (page 19) and Appendices A and B of the 2020 ACIP recommendations for the prevention of hepatitis A infection: www.cdc.gov/mmwr/volumes/69/rr/pdfs/rr6905a1-H.pdf.

Below is a brief summary of the recommendations:

Preexposure prophylaxis with IG for travel to areas of intermediate or high hepatitis A endemicity:

  • Infants younger than age 6 months and other travelers for whom HepA vaccine is declined or contraindicated
  • Previously unvaccinated people with chronic liver disease vaccinated within 2 weeks of departure may consider IG in addition to vaccination, based upon the clinician’s risk assessment
  • Previously unvaccinated people who are immunocompromised may consider IG in addition to vaccination, regardless of the timing of vaccination, based upon the clinician’s risk assessment
  • Previously unvaccinated people who are over age 40 years and vaccinated within 2 weeks of departure may consider IG in addition to vaccination, based upon the clinician’s risk assessment

Postexposure prophylaxis with IG within 2 weeks after exposure to hepatitis A virus (HAV):

  • Infants under age 12 months
  • Previously unvaccinated immunocompromised adults (including HIV+), in addition to vaccination
  • Previously unvaccinated adults with chronic liver disease, in addition to vaccination
  • Previously unvaccinated adults over age 40 years, consider IG in addition to vaccination, based upon clinician risk assessment
  • People with HIV infection, previously vaccinated, consider IG following a high-risk exposure (household or sexual contact), based upon clinician risk assessment
Last reviewed: June 25, 2023

No.

Last reviewed: April 5, 2024

There are no data on the effectiveness of pneumococcal conjugate vaccine given by the intravenous route. The patient has renal disease, so it is important to ensure that the dose they receive is effective. CDC recommends repeating the dose.

Last reviewed: December 28, 2022

The Shingrix adjuvant solution may contain up to 0.75 mL of liquid. The entire volume of the adjuvant solution should be withdrawn and used to reconstitute the lyophilized vaccine. After mixing, withdraw the recommended dose of 0.5 mL. Discard any reconstituted vaccine left in the vial.

Last reviewed: March 9, 2022

In April 2022, CDC published updated recommendations from the Advisory Committee on Immunization Practices (ACIP) for the use of hepatitis B vaccine (HepB) in adults. In addition to routine universal childhood HepB vaccination, CDC now recommends catch-up vaccination of all adults younger than age 60 years not previously vaccinated. CDC also recommends that healthcare providers offer HepB vaccination to all adults age 60 or older and routinely given to any adult in this age group known to be at risk. Access the ACIP recommendation: www.cdc.gov/mmwr/volumes/71/wr/pdfs/mm7113a1-H.pdf.

Last reviewed: July 21, 2023

In March 2023, CDC published updated hepatitis B screening and testing guidelines for all adults age 18 years or older. In brief, it is recommended that all adults should be serologically screened for hepatitis B at least one time using a triple panel test, regardless of vaccination history. The triple panel includes antibody
to hepatitis B surface antigen (anti-HBs), total core antibody (anti-HBc), and surface antigen (HBsAg). Pregnant people should be tested for HBsAg during each pregnancy, regardless of testing or vaccination history. After the one-time screening, unvaccinated, susceptible individuals at ongoing risk should be tested periodically for infection. In addition, anyone who requests testing should be tested. Access the CDC recommendations: www.cdc.gov/mmwr/volumes/72/rr/pdfs/rr7201a1-H.pdf.

Last reviewed: July 21, 2023

Anyone can be infected with hepatitis B. Everyone can benefit from knowing their status and being protected. The majority of adults reported to CDC in recent years with acute hepatitis B have no reported risk factor for infection. Risk factors for exposure are so numerous and diverse that most adults, even those who don’t think of themselves as at risk, may find themselves at risk at some point in their lives.

Infants and children have been routinely vaccinated since the 1990s. As a result, we see very little hepatitis B in the routinely vaccinated age groups; however, rates have been steady or rising in unvaccinated older adults. CDC recommends extending this vaccine protection to all adults in a catch-up vaccination program. This is a crucial step toward the goal of eliminating hepatitis B and the liver disease and cancer it causes.

Last reviewed: July 21, 2023

Yes. Breastfeeding does not interfere with the response to MMR vaccine. Vaccination of a woman who is breastfeeding poses no risk to the infant being breastfed. Although it is believed that rubella vaccine virus, in rare instances, may be transmitted via breast milk, the infection in the infant is asymptomatic.

Last reviewed: June 19, 2023

Recommendations for adult dialysis patients vary by age and pneumococcal vaccination history:

  • Adult dialysis patients who have not previously received pneumococcal vaccination should receive either PCV20 alone or a series of PCV15 followed by PPSV23 at least 8 weeks later. No further pneumococcal vaccines are recommended.
  • Adult dialysis patients who are age 19 through 64 and have already received one dose of PPSV23 may receive either one dose of PCV20 or PCV15 alone one year after the dose of PPSV23; no further doses of PPSV23 are recommended.
  • Adult dialysis patients turning 65 who received PCV13 and PPSV23 before age 65, should receive either one dose of PCV20 or PPSV23. PCV20 should be given at least 5 years after the last pneumococcal vaccination. If PPSV23 is used, it should be given at least 5 years after the last dose of PPSV23 and at least 8 weeks after PCV13.
  • Adult dialysis patients who have already received PCV13 and have received a PPSV23 vaccination since turning 65 are not routinely recommended to receive any additional doses of pneumococcal vaccine. They have the option to receive a dose of PCV20 at least 5 years after their most recent pneumococcal vaccination on the basis of shared clinical decision-making, based upon their risk of pneumococcal disease and desire for additional protection.
Last reviewed: April 5, 2024

Yes. V-safe is a vaccine safety monitoring system that lets recipients of certain new vaccines share with CDC how they feel after vaccination by receiving and responding to a series of periodic text messages. This is a voluntary system and individual recipients must register to participate V-safe. V-safe is available to all RSV vaccine recipients but is not being used for nirsevimab preventive antibody. For information, or to register, visit CDC’s V-safe website at: www.cdc.gov/vaccinesafety/ensuringsafety/monitoring/v-safe/index.html.

Last reviewed: January 22, 2024

We already encourage them to stay home from work when they are sick. Unfortunately, by the time a HCP has symptoms of influenza, they may have already exposed many patients since the virus is shed for 1–2 days before symptoms begin. Further, many studies show that HCP often go to work while they are sick and may be infectious to others. Start planning early to make sure all employees in your work setting receive annual influenza vaccination before the influenza season begins.

Last reviewed: September 10, 2023

Varicella zoster immune globulin (VariZIG, Saol Therapeutics) is a human blood product prepared from plasma obtained from healthy, volunteer blood donors identified by routine screening to have high antibody titers to varicella-zoster virus. The first varicella zoster immune globulin, VZIG, became available in 1978. In a study of immunocompromised children who were administered VZIG within 96 hours of exposure, approximately one in five exposed children developed clinical varicella, and one in 20 developed subclinical disease compared with 65%—85% attack rates among historical controls. In 2006, VZIG was discontinued and a new product, VariZIG, became available.

Last reviewed: May 16, 2023

No, it is not recommended to give another dose of Tdap in such cases. Optimal timing for Tdap administration is between 27 and 36 weeks’ gestation because that stage of pregnancy is best for transplacental antibody movement to the fetus.

More information is available at www.cdc.gov/mmwr/volumes/67/rr/pdfs/rr6702a1-H.pdf, pages 22–23.

Last reviewed: March 31, 2022

Hepatitis A vaccination is recommended for people age 6 months or older who are traveling to or working in an area of the world at intermediate or high risk of hepatitis A transmission. Areas of low risk include the United States, Canada, Japan, New Zealand, Australia and Western Europe. Visit the CDC’s Traveler Health website for more information about specific destinations and current outbreaks or travel notices (https://wwwnc.cdc.gov/travel/). When in doubt, vaccinate.

Last reviewed: June 25, 2023

PPSV23 is not effective in children younger than 24 months of age. PPSV23 given at this age should not be considered to be part of the pneumococcal vaccination series. Pneumococcal conjugate vaccine should be administered as soon as the error is discovered. Any time the wrong vaccine is given, the parent/patient should be notified.

Last reviewed: December 28, 2022

PreHevbrio (VBI, 3-dose series), Heplisav-B (Dynavax, 2-dose series), and Twinrix (GSK, combination HepA-HepB, 3-dose series) are approved for adults age 18 years and older. Engerix-B (GSK) and Recombivax HB (Merck), both administered as a 1.0 mL 3-dose series, are approved for adults age 20 years and older; young adults who are age 19 receive the 0.5 mL pediatric dose of Engerix-B and Recombivax HB.

Last reviewed: July 21, 2023

According to the American Pharmacist Association, all states allow pharmacists to administer zoster vaccine. Not all pharmacists provide vaccination services, and of those who do, not all administer zoster vaccine. It is best to call the pharmacy ahead of time to find out if they have Shingrix to administer to your patients. The vaccine must be administered in the pharmacy. Do NOT instruct the patient to transport the vaccine from the pharmacy back to your office. This could damage the potency of the vaccine.

Last reviewed: March 9, 2022

In general, one HepB series is needed in a lifetime, with rare exceptions described at the end of this answer.

As of April 2022, CDC recommends HepB vaccination of all adults age 60 or older who are in any of the following risk groups (vaccination also may be offered to age 60 and older, regardless of risk):

  • All adults age 60 years and older with risk factors for hepatitis B:
    • People at risk for infection by sexual exposure
      • Sex partners of people testing positive for HBsAg
      • Sexually active people who are not in a long-term, mutually monogamous relationship (e.g., those with more than one sex partner during the previous 6 months)
      • People seeking evaluation or treatment for a sexually transmitted infection
      • Men who have sex with men
    • People at risk for infection by percutaneous or mucosal exposure to blood
      • People with current or recent injection drug use
      • Household contacts of people testing positive for HBsAg
      • Residents and staff members of facilities for people with developmental disabilities
      • Healthcare and public safety personnel with reasonably anticipated risk for exposure to blood or blood-contaminated body fluids
      • People on maintenance dialysis, including in-center or home hemodialysis and peritoneal dialysis, and people who are predialysis
      • People with diabetes, at the discretion of the treating clinician
    • Others
      • International travelers to countries with high or intermediate levels of endemic hepatitis B virus (HBV) infection (HBsAg prevalence of 2% or higher)
      • People with hepatitis C virus infection
      • People with chronic liver disease (including, but not limited to, people with cirrhosis, fatty liver disease, alcoholic liver disease, autoimmune hepatitis, and an alanine aminotransferase or aspartate aminotransferase level greater than twice the upper limit of normal)
      • People with HIV infection
      • People who are incarcerated

The official CDC recommendations for HepB vaccination of adults are available at www.cdc.gov/mmwr/volumes/71/wr/pdfs/mm7113a1-H.pdf. Immunize.org has developed a standing order template for adult HepB vaccination: www.immunize.org/catg.d/p3076.pdf.

In general, people who have documented completion of a HepB series at any point or who have a history of previous HBV infection should not receive additional HepB vaccination, although there is no evidence that additional vaccination is harmful. In settings where the patient population has a high rate of previous HBV infection, prevaccination testing, which may be performed at the same visit when the first dose of vaccine is administered, might reduce costs by avoiding complete vaccination of people who are already immune. However, prevaccination testing is not required and should not create a barrier to vaccination.

Revaccination may be indicated for certain high-risk adults, including healthcare workers who are documented non-responders to an initial HepB series, and certain people who receive dialysis or who are immunocompromised. For specific revaccination guidance, see the 2018 ACIP recommendations for the prevention of hepatitis B at www.cdc.gov/mmwr/volumes/67/rr/pdfs/rr6701-H.pdf (pages 23–24).

People with risk factors who are 60 and older should be vaccinated and other people older than 60 may be vaccinated.

Last reviewed: July 21, 2023

For details on preexposure protection of international travelers age 12 months and older, refer to Appendix A on page 35 of the current ACIP recommendations for the prevention of hepatitis A: www.cdc.gov/mmwr/volumes/69/rr/pdfs/rr6905a1-H.pdf.

Healthy people age 12 months through 40 years who are planning travel to an area with high or intermediate HAV endemicity and have not received HepA vaccine should receive a single dose of HepA vaccine as soon as travel is considered and should complete the 2-does series according to the routine schedule.

People with chronic liver disease as well as adults older than 40 years of age, immunocompromised people, and people with other chronic medical conditions planning to depart to an area with high or intermediate HAV endemicity in less than 2 weeks should receive the initial dose of HepA vaccine and may also simultaneously be administered immune globulin (IG) at a separate anatomic injection site (for example in separate limbs).

ACIP revised its recommendations for preexposure hepatitis A vaccination for travelers in 2018 to include vaccination of infants 6 through 11 months of age. All infants of this age traveling internationally should be given a dose of measles, mumps, rubella vaccine (MMR) before travel. Due to the potential interference of hepatitis A IG with MMR vaccine effectiveness, an off-label dose of HepA vaccine is recommended instead of IG in this situation. The travel-related dose for infants 6–11 months of age should not be counted toward the routine 2-dose series. The routine 2-dose HepA and MMR vaccination series should be initiated at age 12 months according to the routine, age-appropriate vaccination schedule.

Infants younger than 6 months and travelers who elect not to receive vaccine or for whom vaccine is contraindicated should receive a single 0.1 mL/kg dose of IG before travel when protection against HAV is recommended. If travel is for more than 1 month, a dose of 0.2 mL/kg should be administered. A 0.2 mL/kg dose can be repeated every 2 months for travel of more than 2 months duration.

Last reviewed: June 25, 2023

CDC’s guidance is to ignore the remote history of PCV7 and evaluate the patient as if he has never had pneumococcal vaccination. The patient should receive either PCV20 alone or PCV15 in series with PPSV23 given at least one year later. If using PCV15, and if the high risk condition is immunocompromising or if the patient has a cochlear implant or cerebrospinal fluid leak, you may consider administering the PPSV23 as soon as 8 weeks after PCV15.

Last reviewed: April 5, 2024

Because HCP provide care to patients at high risk for complications of influenza, they should be considered a high-priority group for receiving vaccination. Achieving high rates of vaccination among HCP will protect staff and their patients, and reduce disease burden and healthcare costs. Vaccination rates of HCP are still too low; overall only 80% of HCP reported influenza vaccination during the 2021–22 season.

Influenza vaccination key points for HCP include:

  • All HCP should be educated regarding the benefits of influenza vaccination
  • Influenza vaccine should be administered annually to all eligible HCP
  • A signed declination should be obtained from HCP who decline influenza vaccination
  • Healthcare facilities should monitor HCP influenza vaccination coverage and declination at regular intervals
  • HCP vaccination coverage should be used as one measure of a patient-safety quality program

In 2011, ACIP published “Immunization of Health-Care Personnel,” which includes information about all recommended vaccines (see www.cdc.gov/mmwr/pdf/rr/rr6007.pdf).

Last reviewed: September 10, 2023

Nirsevimab is contraindicated in persons with a history of severe allergic reactions (e.g., anaphylaxis) after a previous dose or to a product component. As with any injection, when administering nirsevimab to children with increased risk for bleeding, providers should follow ACIP’s general best practice guidelines for immunization.

Last reviewed: January 22, 2024

Everyone age 6 months and older is recommended to receive at least one dose of updated (2023–2024 Formula) COVID-19 vaccine, regardless of past vaccination history. Any updated (2023–2024 Formula) COVID-19 vaccine received in another country that is listed for emergency use by the World Health Organization (WHO-EUL) or authorized or licensed for use by the FDA counts toward fulfilling this recommendation.

CDC has provided additional details based upon age and immunocompromised status at its website: www.cdc.gov/vaccines/covid-19/clinical-considerations/interim-considerations-us-appendix.html#appendix-a.

A list of the vaccines that have already received WHO-EUL status is available here: https://extranet.who.int/prequal/vaccines/covid-19-vaccines-who-emergency-use-listing.

Last reviewed: March 19, 2024

ACIP does not recommend repeated doses of Tdap for fathers or other family members or caregivers of infants during every pregnancy. The recommendation for Tdap vaccination with each pregnancy to optimize immunity for the infant applies only to the pregnant mother.

The practice of “cocooning” infants by making a particular effort to vaccinate caregivers who have not received Tdap vaccination has been recommended by ACIP since 2005; however, the practice has been difficult to implement fully and may not be effective alone as a strategy for protecting newborns from pertussis exposure. The combined strategy of Tdap vaccination during each pregnancy, cocooning, and administering the childhood DTaP series on schedule provides the best protection to the infant.

Last reviewed: March 31, 2022

Yes, but there should be sufficient time between the blood product and the MMR to reduce the chance of interference. The interval depends on the blood product received. See Table 3-6 of ACIP’s “General Best Practice Guidelines for Immunization” for more information, available at www.cdc.gov/vaccines/hcp/acip-recs/general-recs/timing.html.

Last reviewed: June 19, 2023

Although PCV and PPSV23 should not be administered at the same visit, CDC does not recommend repeating either vaccine dose should this occur. You should inform the patient of the error and let them know that they will not need to repeat either dose.

Last reviewed: December 28, 2022

CDC recommends that if a provider mistakenly administers varicella vaccine to a person for whom zoster vaccine is indicated, no specific safety concerns exist, but the dose should not be considered valid. You should administer a dose of Shingrix to the patient during that same visit (same day). If the error is not detected and corrected on the same day, Shingrix should be administered at least 8 weeks after receipt of the varicella vaccine. However, if Shingrix is administered less than 8 weeks after the varicella vaccine, it does not need to be repeated. A second dose of Shingrix should be given 2–6 months after the first dose of Shingrix.

These events should be documented and procedures put in place, such as checking the vial label 3 times to be sure you are administering the product you intend, to prevent this from happening again.

Last reviewed: March 9, 2022

Prior vaccine recommendations put the burden on the patient to ask for HepB vaccination if they wanted it. The recommendations published in 2022 make vaccinating adults much easier because CDC recommends that healthcare providers routinely offer HepB vaccine to ALL adult patients, including those over 60 without known risk factors. The idea of this change is to shift the burden of requesting vaccination off the patient and instead allow the provider to offer the vaccine routinely.

Last reviewed: July 21, 2023

In certain limited circumstances, adults with immunocompromising conditions have an option for vaccination that includes multiple doses of PPSV23. Under the ACIP recommendations published in January 2022, adults age 19 through 64 who have already received a dose of PCV13 (as previously recommended for those with immunocompromising conditions) may complete the immunization schedule with either PCV20 or PPSV23:

  • Option 1: Administer one dose of PCV20 at least one year after the dose of PCV13. No additional doses of pneumococcal vaccine are recommended.
  • Option 2: Administer a dose of PPSV23 at least 8 weeks after the PCV13. Those who are still younger than age 65 at least 5 years after the dose of PPSV23 may receive a second dose of PPSV23 or a dose of PCV20 at that time. If two doses of PPSV23 are given, plan to review the pneumococcal vaccination recommendations again once this person turns 65.
Last reviewed: April 5, 2024

This patient, like other adults, is considered up to date after receiving a single dose of updated (2023–2024 Formula) COVID-19 vaccine at least 8 weeks after his most recent COVID-19 vaccination.

Last reviewed: March 19, 2024

RSV vaccines are contraindicated for and should not be administered to persons with a history of severe allergic reaction, such as anaphylaxis, to any component of the vaccine. People experiencing moderate or severe acute illness with or without fever should delay RSV vaccination until they are improved, as a precaution.

Last reviewed: January 22, 2024

It is important to vaccinate all healthcare personnel, including paid and unpaid workers who may be exposed to patients or infectious materials. This includes direct patient care staff (e.g., physicians, nurses, and therapists), and staff and volunteers in pharmacy, radiology, laboratory, human resources, facilities management (housekeeping), food services, and laundry. Vaccination should include healthcare staff in all settings, such as hospitals, outpatient clinics, pharmacies, emergency response, nursing homes and assisted living facilities, and home care.

Last reviewed: September 10, 2023

Yes. Receipt of RhoGam is not a reason to delay vaccination. For more information see the ACIP “General Best Practice Guidelines for Immunization”, available at www.cdc.gov/vaccines/hcp/acip-recs/general-recs/timing.html.

Last reviewed: June 19, 2023

Varicella zoster immune globulin, VariZIG (Saol Therapeutics), is recommended for patients without evidence of immunity to varicella who are at high risk for severe varicella and complications, who have been exposed to varicella or herpes zoster, and for whom varicella vaccine is contraindicated. Patient groups recommended by CDC to receive VariZIG include the following:

  • Immunocompromised patients without evidence of immunity
  • Newborn infants whose mothers have signs and symptoms of varicella around the time of delivery (i.e., 5 days before to 2 days after)
  • Hospitalized preterm infants born at 28 weeks or more of gestation whose mothers do not have evidence of immunity to varicella
  • Hospitalized preterm infants born at less than 28 weeks of gestation or who weigh 1,000 grams or less at birth, regardless of their mothers’ evidence of immunity to varicella
  • Pregnant people without evidence of immunity

CDC recommends administration of VariZIG as soon as possible after exposure to varicella-zoster virus, ideally within 96 hours, but not beyond 10 days after exposure. The most recent recommendations for the use of VariZIG were published in 2013 and are available at www.cdc.gov/mmwr/pdf/wk/mm6228.pdf on pages 574—576.

Last reviewed: May 16, 2023

To maximize maternal antibody response and passive antibody transfer to the infant, the optimal time to administer Tdap is between 27 and 36 weeks’ gestation, preferably during the early part of that window. However, Tdap can be administered at any time during pregnancy.

Last reviewed: March 31, 2022

Yes. If time allows, use the standard Twinrix schedule of 3 doses given intramuscularly on a 0-, 1-, and 6-month schedule. If travel is imminent the accelerated 4-dose Twinrix schedule can be used, which is 3 doses given on days 0, 7, and 21-30 days and a booster dose at 12 months.

Last reviewed: June 25, 2023

CDC recommends that if a provider mistakenly administers varicella vaccine to a person for whom zoster vaccine is indicated, no specific safety concerns exist, but the dose should not be considered valid. You should administer a dose of Shingrix to the patient during that same visit (same day). If the error is not detected and corrected on the same day, Shingrix should be administered at least 8 weeks after receipt of the varicella vaccine. However, if Shingrix is inadvertently administered less than 8 weeks after the varicella vaccine, CDC experts state that the Shingrix dose does not need to be repeated if given at least 24 days after the varicella vaccine (in other words, 4 weeks minus the 4-day grace period). A second dose of Shingrix should be given 2–6 months after the first dose of Shingrix.

These events should be documented and procedures put in place, such as checking the vial label 3 times to be sure you are administering the product you intend, to prevent this from happening again.

Last reviewed: December 28, 2022

The HepB series is now recommended for all people age 59 years and younger. Among older age groups the risk of acute hepatitis B is lower: HepB may be administered to unvaccinated adults with diabetes age 60 years and older at the discretion of the treating clinician.

In 2011, CDC first published ACIP recommendations that HepB vaccine be given to adults with diabetes because of studies showing that adults with diabetes and no other hepatitis B risk factors had twice the odds of developing acute hepatitis B compared to adults without diabetes or other risk factors. There also have been a number of outbreaks of HBV infection in settings that provide assisted blood glucose monitoring for people with diabetes.

No serologic testing or additional HepB vaccination is recommended for adults who have documentation of receiving a complete HepB series at any time in the past. For those who did not complete the vaccination series, no maximum interval between doses exists that would make the HepB vaccination series ineffective or that would require restarting the series.

Last reviewed: July 21, 2023

There is no waiting period. The varicella vaccine dose can be given at any time after the Shingrix dose. Review your procedures to prevent this from happening again. Always check the label 3 times to ensure you are administering the product intended. Such an error also should be reported to the Vaccine Adverse Event Reporting System (VAERS) by phone 1-800-822-7967 or online at https://vaers.hhs.gov.

Last reviewed: March 9, 2022

That is not necessary. CDC has stated that either PCV20 or PPSV23 may be used in this circumstance. If PCV20 is used, no further pneumococcal vaccine doses are indicated.

Last reviewed: April 5, 2024

People with HIV infection are at increased risk for severe complications if infected with measles. It is safe to vaccinate people with HIV infection who are not severely immunosuppressed. The current criteria for safe MMR vaccination of people with HIV infection are shown below, from the CDC General Best Practices Guidelines (see the section on altered immunocompetence, www.cdc.gov/vaccines/hcp/acip-recs/general-recs/immunocompetence.html):

Two doses of MMR vaccine are recommended for all HIV-infected people age 12 months or older who do not have evidence of current severe immunosuppression (individuals age 5 years or younger must have CD4+T lymphocyte [CD4+] percentages at least 15% for at least 6 months, and individuals older than age 5 years must have CD4+ percentages at least 15% and CD4+ cell counts of at least 200 lymphocytes/mm3 for at least 6 months) and do not have current evidence of measles, rubella, and mumps immunity.

In cases when only CD4+ cell counts or only CD4+ percentages are available for those older than age 5 years, the assessment of severe immunosuppression can be based on the CD4+ values (count or percentage) that are available. In cases when CD4+ percentages are not available for those age younger than 5 years, the assessment of severe immunosuppression can be based on age-specific CD4+ counts at the time CD4+ counts were measured; i.e., absence of severe immunosuppression is defined as at least 6 months above age-specific CD4+ count criteria: CD4+count greater than 750 lymphocytes/mm3 while age 12 months or younger, and CD4+count at least 500 lymphocytes/mm3 while age 1 through 5 years. Similarly, repeat doses of MMR vaccination are recommended for individuals with perinatal HIV infection who were vaccinated before establishing effective combination antiretroviral therapy (cART). They should receive 2 appropriately spaced doses of MMR vaccine once effective cART has been established (individuals age 5 years or younger must have CD4+ percentages of at least 15% for at least 6 months; individuals older than 5 years of age must have CD4+ percentages at least 15% and CD4+ counts of at least 200 lymphocytes/mm3 for at least 6 months) unless they have other acceptable current evidence of measles, rubella, and mumps immunity.

HIV-infected people who are receiving regular doses of IGIV are unlikely to respond to varicella vaccine or MMR vaccine because of the presence of passively acquired antibody. However, because of the potential benefit, MMR and varicella vaccines should be considered approximately 14 days before the next scheduled dose of IGIV (if not otherwise contraindicated), although an optimal immune response might not occur depending on the presence of neutralizing antibodies against the vaccine virus. Vaccination should be repeated (if not otherwise contraindicated) after the recommended interval (see Table 3-6 in the Timing and Spacing of Immunobiologics of this document). In most cases, this is after the therapy has been discontinued.

Administer the first dose at 12 through 15 months and the second dose to children age 4 through 6 years, or as early as 28 days after the first dose.

Last reviewed: June 19, 2023

RSVPreF3 (Arexvy, GSK) is supplied as a single-dose vial of lyophilized antigen component (powder) and a single-dose vial of adjuvant suspension component (liquid). Both the liquid and the powder should be stored refrigerated between 2°C and 8°C (36°F and 46°F) in the original package in order to protect vials from light. Do not freeze. Discard if either component has been frozen. After reconstitution, administer immediately or store in the refrigerator between 2°C and 8°C (36°F to 46°F) or at room temperature (defined for this vaccine as up to 25°C [77°F]) for up to 4 hours before use. Discard reconstituted vaccine if not used within 4 hours.

RSVpreF (Abrysvo, Pfizer) is supplied in a kit that includes a vial of lyophilized antigen component (a white powder), a prefilled syringe with a sterile water diluent, and a vial adapter. Store at refrigerated temperatures between 2°C and 8°C (36°F and 46°F) in the original carton. Do not freeze. Discard if frozen. Follow reconstitution guidelines at www.fda.gov/media/168889/download. After reconstitution, administer immediately or store at room temperature (defined for this vaccine as 15ºC to 30ºC [59ºF to 86ºF]) for up to 4 hours. Do not store reconstituted Abrysvo vaccine in the refrigerator or freezer. Discard reconstituted vaccine if not used within 4 hours.

Last reviewed: January 22, 2024

An asymptomatic person who is scheduled for COVID-19 vaccination and is exposed to SARS-CoV-2 virus may be vaccinated; however, COVID-19 vaccination after exposure is not recommended as post-exposure prophylaxis, so vaccination should not be expected to prevent illness caused by past exposure. A person who is currently sick with a respiratory virus should defer vaccination until at least the recovery from the acute illness, and consider additional measures to prevent spread, in accordance with current CDC guidance. Healthcare facilities may have specific policies in place to reduce the risk of spread of respiratory viruses to healthcare staff and other patients.

CDC summarizes its current guidance on respiratory viruses (updated March 2024) here: www.cdc.gov/respiratory-viruses/guidance/respiratory-virus-guidance.html.

People who recently had SARS-CoV-2 infection and are due for a COVID-19 vaccine may consider delaying the dose by up to 3 months from symptom onset or positive test (if infection was asymptomatic). According to CDC, increasing the time between infection and vaccination may result in an improved immune response to vaccination. At this time, there is evidence of a low risk of reinfection in the weeks following infection. A recipient’s individual risks for severe disease and current COVID-19 conditions in the community should be taken into account when deciding whether to delay vaccination up to 3 months after infection.

Last reviewed: March 19, 2024

No. There is no recommendation for a booster dose of HepA if a patient has completed the 2-dose series at any age.

Last reviewed: June 25, 2023

All people working in long-term care facilities who do not have a valid contraindication should receive annual influenza vaccination.

Last reviewed: September 10, 2023

VariZIG is supplied in 125-IU vials and should be administered intramuscularly as directed by the manufacturer. The recommended dose is 125 IU/10 kg of body weight, up to a maximum of 625 IU (five vials). The minimum dose is 62.5 IU (0.5 vial) for patients weighing 2.0 kg or less and 125 IU (one vial) for patients weighing 2.1–10.0 kg. VariZIG is available from Saol Therapeutics. For ordering information see varizig.com/liquid-product_info.html.

Last reviewed: September 5, 2020

While the mother should have been given Tdap rather than Td, the Tdap dose may be given at any interval since the Td dose was given and preferably between 27 and 36 weeks’ gestation.

Last reviewed: March 31, 2022

There is no waiting period. The varicella vaccine dose can be given at any time after the RZV dose.

Last reviewed: December 28, 2022

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