Ask the Experts is one of our most popular destinations for healthcare professionals. Our experts provide clear, easy-to-understand answers to commonly asked questions about vaccines and their use.
Store any brand of MenACWY, MenB, or MenABCWY vaccine at refrigerator temperature, between 2° and 8°C (between 36° and 46°F). These vaccines must not be frozen. Vaccine that has been frozen or exposed to freezing temperature should not be used. Do not use after the expiration date.
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.
Shingrix zoster vaccine 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.
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.
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.
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/imz-best-practices/altered-immunocompetence.html.
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.
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.
People with cancer need to be protected from influenza. All cancer patients should receive an age-appropriate inactivated or recombinant influenza vaccine. They should not be given the live virus vaccine, FluMist (LAIV). Cancer patients and survivors are at higher risk for complications from influenza, including hospitalization and death.
In clinical trials, the vast majority of infants had no side effects detected after nirsevimab (Beyfortus, Sanofi) or clesrovimab (Enflonsia, Merck) administration. For both products, the proportion of infants experiencing side effects was very similar in the intervention and placebo groups.
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).
Similar reactions were seen with clesrovimab. Rash was seen within two weeks after injection (2.3% of clesrovimab recipients vs. 1.9% of placebo recipients). Redness or swelling at the injection site each were reported in fewer than 4% of clesrovimab recipients, with a similar proportion of placebo recipients also reporting these side effects. See the product package inserts for more details.
When using the presentation of Shingrix that requires reconstitution, 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.
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.
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.
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.
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:
Postexposure prophylaxis with IG within 2 weeks after exposure to hepatitis A virus (HAV):
No.
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.
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.
Adverse reactions occurring after administration of nirsevimab (Beyfortus, Sanofi) alone or clesrovimab (Enflonsia, Merck) 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 or clesrovimab 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 or clesrovimab on the VAERS form.
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.
Beginning with the 2025–2026 season, a single dose of 2025–2026 Formula Nuvaxovid adjuvanted protein COVID-19 vaccine is recommended for all recipients age 12 through 64 years who are not moderately or severely immunocompromised, regardless of their vaccination history. Those age 65 years or older are recommended to receive a second dose of any 2025–2026 Formula COVID-19 vaccine 6 months after the first 2025–2026 Formula dose (minimum interval 2 months if using Comirnaty, Spikevax, or Nuvaxovid; minimum interval 3 months if using mNexspike).
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.
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.
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.
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. PreHevbrio (VBI, 3-dose series), was available and used in adults age 18 years and older between 2021 and 2024 before it was removed from the market following the bankruptcy of its manufacturer.
Recommendations for adult dialysis patients vary by age and pneumococcal conjugate (PCV) or polysaccharide (PPSV23) vaccination history:
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.
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.
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.
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.
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.
Pneumococcal polysaccharide vaccine (PPSV23, Pneumovax, Merck) is not licensed or assumed to be effective in children younger than 24 months of age. PPSV23 given at this age should not be counted as 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.
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 Arexvy (GSK), Abrysvo (Pfizer), and mResvia (Moderna) recipients. For information, or to register, visit CDC’s V-safe website at: www.cdc.gov/vaccine-safety-systems/v-safe/index.html.
We encourage HCPs 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.
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 PCV20 or PCV21 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.
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 zoster vaccine 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.
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.
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.
Although PCV15 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.
Nirsevimab (Beyfortus, Sanofi) and clesrovimab (Enflonsia, Merck) are contraindicated in persons with a history of severe allergic reactions (e.g., anaphylaxis) after a previous dose of the same product or to a product component. As with any injection, when administering nirsevimab or clesrovimab to children with increased risk for bleeding, providers should follow ACIP’s general best practice guidelines for immunization of children with bleeding disorders: www.cdc.gov/vaccines/hcp/imz-best-practices/special-situations.html#cdc_report_pub_study_section_8-vaccinating-persons-with-increased-bleeding-risk.
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.
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).
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.
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 and administered to anyone age 60 and older, regardless of risk):
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).
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.
No. As of October 2024, CDC recommends that adults with immunocompromising conditions who received a dose of PPSV23 in the past and were previously recommended to receive a second PPSV23 dose at least 5 years after that initial PPSV23 dose should now complete their pneumococcal immunization schedule with PCV20 or PCV21 at least 5 years after the PPSV23 dose.
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.
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:
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.
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.
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.
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.
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.
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/imz-best-practices/timing-spacing-immunobiologics.html.
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: 3 doses given on days 0, 7, and 21-30 days and a booster dose at 12 months.
In October 2024, CDC updated its guidance to state that an adult who received PCV13 should receive PCV20 or PCV21at least 1 year later. PPSV23 is no longer recommended as an option following PCV13.
No. There is no recommendation for a booster dose of HepA if a patient has completed the 2-dose series at any age.
No. The Shingrix zoster vaccine does not count as a vaccination against primary varicella infection (chickenpox). The first varicella vaccine dose can be given at any time after the Shingrix dose. The second dose of varicella vaccine should be given 4 to 8 weeks after the first dose. You should always check the label 3 times to ensure you are administering the product intended.
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.
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.
No, gestational diabetes is not classified as a risk factor for acute hepatitis B infection. The increased risk of acute hepatitis B infection has been associated with type 1 and type 2 diabetes; however, all people age 59 years or younger are now recommended to be vaccinated against hepatitis B.
Both protein-based vaccines (Abrysvo, Pfizer; Arexvy, GSK) are stored in the refrigerator. RSVPreF3 (Arexvy) 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.
All people working in long-term care facilities who do not have a valid contraindication should receive annual influenza vaccination.
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/imz-best-practices/altered-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.
