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.
Aim for nirsevimab (Beyfortus, Sanofi) or clesrovimab (Enflonsia, Merck) administration in the first week of life for infants born shortly before or during the RSV season (typically October through March, unless directed otherwise by state or territorial public health officials). Ideally, eligible infants should be immunized before discharge from the birthing facility. Eligible infants with prolonged birth hospitalizations due to prematurity or other causes should be immunized shortly before or promptly after discharge.
Infants younger than age 8 months born outside of the RSV season, as well as older children at high risk who are recommended be protected in their second RSV season, should aim to be immunized shortly before the start of the RSV season (typically October).
If the ideal timing is missed, age-eligible infants and children who have not yet received a dose may be immunized at any time during the RSV season.
If you are located in Alaska, Hawaii, or another region of the United States with a different pattern of RSV circulation, follow the timing guidance of your state or territorial public health officials.
In the pneumococcal vaccine recommendations for adults that were updated January 28, 2022, the many risk groups for pneumococcal disease were combined into one group with respect to vaccine recommendations. All are now recommended to receive PCV20 or PCV21 alone or PCV15 followed by PPSV23 one year later. ACIP no longer recommends the use of PPSV23 alone for any adult. Cigarette smokers too young for routine age-based vaccination recommendations who received PPSV23 alone in the past may now receive a dose of any recommended pneumococcal conjugate vaccine option (PCV15, PCV20, or PCV21) at least one year after their dose of PPSV23.
The most common adverse events following MenACWY vaccination were injection site pain, swelling or redness. Other reported symptoms included malaise and headache.
There is no waiting period for administering Shingrix following transfusion. Shingrix contains no live virus so may be given at any time after receipt of a blood product.
No. Since 2006, well over 100 million doses of HPV vaccine have been administered in the United States. Among all reports to the Vaccine Adverse Event Reporting System (VAERS) following HPV vaccines, the most frequently reported symptoms overall were dizziness; fainting; headache; nausea; fever; and pain, redness, and swelling in the arm where the shot was given. Although deaths have been reported among vaccine recipients none has been conclusively shown to have been caused by the vaccine. Occurrences of rare conditions, such as Guillain-Barré Syndrome (GBS) have also been reported among vaccine recipients but there is no evidence that HPV vaccination increased the rate of GBS above what is normally expected in the population.
CDC, working with the FDA and other immunization partners, continues to monitor the safety of HPV vaccines. You can find complete information on this and other vaccine safety issues www.cdc.gov/vaccine-safety/vaccines/hpv.html and at www.cdc.gov/vaccine-safety/vaccines/hpv.html.
The DTaP recipient received the appropriate amount of tetanus toxoid and MORE diphtheria toxoid and pertussis antigen than is recommended. Count the dose as Tdap, but take measures to prevent this error in the future. The patient does not need a repeat dose of Tdap.
Immune globulin (IG, GamaSTAN, Grifols Therapeutics) is a sterile preparation of concentrated antibodies (i.e., immunoglobulins) made from pooled human plasma processed by cold ethanol fractionation. GamaSTAN is the only IG product licensed in the United States for the prevention of hepatitis A virus (HAV) infection. Only plasma that has tested negative for hepatitis B surface antigen, antibody to human immunodeficiency virus (HIV), and antibody to hepatitis C virus (HCV) is used to produce IG. In addition, the Food and Drug Administration requires that the process used to produce IG include a viral inactivation step or that final products test negative for HCV-RNA by polymerase chain reaction. Anti-HAV concentrations differ among IG lots and decreasing concentrations have been observed over the past 30 years, probably because of the decreasing prevalence of previous HAV infection among plasma donors. In 2017, the dosing of GamaSTAN for HAV prevention was increased to reflect this change in anti-HAV potency.
If you believe the child had varicella disease (that is, breakthrough varicella) after the first dose, the child does not need another dose. If you are uncertain whether the child had varicella or a rash related to varicella vaccination, the second dose should be administered on schedule. If in doubt, give the second dose. If this was a case of breakthrough varicella, a second dose will not be harmful.
The dose should be repeated. If the expired dose is a live virus vaccine, you should wait at least 4 weeks after the previous (expired) dose was given before repeating it. If the expired dose is not a live vaccine, the dose should be repeated as soon as possible. Although simply repeating the dose is preferred, serologic testing to check for immunity at least 4 weeks after certain vaccinations (e.g., measles, rubella, varicella, hepatitis A) may be accepted.
Although some studies have demonstrated a transient increase in replication of HIV following inactivated influenza vaccine, other studies have not found this. This temporary increase in HIV titer has not been associated with deterioration in either T-lymphocyte counts or clinical condition. Annual influenza vaccination with an age-appropriate injectable influenza vaccine benefits HIV-infected people.
CDC has published an immunization information statement (IIS) for RSV preventive antibody products that is the equivalent of the vaccine information statement (VIS) for vaccines. The version available at this time only names nirsevimab, but should also be used with clesrovimab until an updated version is produced. Just as with a VIS, providers should give the IIS to the parent or caregiver before immunization and document it in the medical record.
Access the current RSV preventive antibody IIS and translations in numerous languages from Immunize.org at: www.immunize.org/vaccines/vis/iis-rsv/.
Contraindications:
Precautions:
Important details about the contraindications and precautions for MMR vaccine are in the 2013 MMR ACIP statement, available at www.cdc.gov/mmwr/pdf/rr/rr6204.pdf.
Yes. CDC recommends that all children age 0 through 18 years (and all unvaccinated adults through age 59) be fully vaccinated against hepatitis B. This recommendation is also endorsed by AAP and AAFP and is published as part of the annual Recommended Childhood and Adolescent Immunization Schedule (www.cdc.gov/vaccines/hcp/imz-schedules/child-adolescent-age.html). Vaccination should be initiated for children and teenagers not previously vaccinated and vaccination completed for all those whose vaccine series is incomplete.
All children and adolescents younger than age 19 years (including internationally adopted children) who were born in Asia, the Pacific Islands, Africa, or other intermediate or high-endemic countries or who have at least one parent who was born in a high-endemic area should be tested for HBsAg and should complete the vaccine series if they were not previously vaccinated or were incompletely vaccinated.
Yes. Pneumococcal vaccination is recommended for adults age 19 through 49 years with all types of asthma.
Among children age 2 through 18 years, only those with moderate persistent or severe persistent asthma (regardless of high-dose oral corticosteroids use) should be evaluated for additional pneumococcal vaccine doses beyond the routine age-based schedule. Specific recommendations depend on age and the recipient’s specific pneumococcal vaccination history, including prior doses of any pneumococcal vaccine except PCV7. Prior doses of PCV7 may be ignored for the purposes of determining doses due now.
Yes. The National Vaccine Injury Compensation Program includes payment for injuries determined to have occurred following vaccination with a vaccine routinely recommended for children in the United States. The recipient can be of any age, but the vaccine must be routinely recommended for children and teens through age 18 years. MenACWY is routinely recommended for children so it is included in the program. More information about the program and the covered vaccines is at www.hrsa.gov/vaccine-compensation/covered-vaccines/index.html.
Yes. There are data that show adequate seroprotection using this schedule in young adults. If this schedule is used, you should be aware that the studies were in young adults and might not translate to older adults (age 40 years or older). There are other schedules that offer flexibility in vaccination as well. View www.immunize.org/catg.d/p2081.pdf for a review of different schedules.
Yes. Shingrix recombinant zoster vaccine can be administered in this situation.
Nearly all vaccines have been reported to be associated with fainting (syncope). Post-vaccination syncope has been most frequently reported after three vaccines commonly given to adolescents (HPV, MenACWY, and Tdap). However, it is not known whether the vaccines are responsible for post-vaccination syncope or if the association with these vaccines simply reflects the fact that adolescents are generally more likely to experience syncope due to needle- and pain-related anxiety.
Syncope can cause serious injury. Falls that occur due to syncope after vaccination can be prevented by having the vaccinated person seated or lying down. The person should be observed for 15 minutes following vaccination. For additional information about vaccination-associated syncope, see Immunize.org’s clinical resource, Vaccination-Related Syncope: Information for Healthcare Personnel at www.immunize.org/wp-content/uploads/catg.d/p4260.pdf.
Revaccination of individuals who are up to date on Tdap immunization with an additional dose of Tdap during a pertussis outbreak is currently not recommended.
IG provides protection against HAV infection through passive transfer of antibody. Depending on the IG dosage, protection lasts from 1 to 2 months.
When administered for preexposure prophylaxis, a dose of 0.1 mL/kg will provide protection for up to 1 month and a dose of 0.2 mL/kg will provide protection for up to 2 months. If longer term protection is required and vaccination is contraindicated, a dose of 0.2 mL/kg can be repeated every 2 months. There is no maximum number of times the bimonthly doses of IG may be repeated as long as hepatitis A prophylaxis is required.
For postexposure prophylaxis, the recommended dosage is 0.1 mL/kg.
Transmission of varicella vaccine virus is a rare event, and appears to occur only when the vaccinated person develops a vesicular rash. A maculopapular rash 2 weeks after varicella vaccine may not have been caused by the vaccine. If the rash were caused by the vaccine, the risk of transmission is very small; however, the child should avoid close contact with people who do not have evidence of varicella immunity and who are at high risk of complications of varicella, such as immunocompromised people, until the rash has resolved.
People with medical conditions that contraindicate measles immunization depend on high MMR vaccination coverage among those around them. To help prevent the spread of measles virus, make sure all your staff and patients who can be vaccinated are fully vaccinated according to the U.S. immunization schedule. Also, encourage patients to remind their family members and other close contacts to get vaccinated if they are not immune.
If patients who cannot get MMR vaccine are exposed to measles, CDC has guidelines for immune globulin for post-exposure prophylaxis which can be found at www.cdc.gov/mmwr/pdf/rr/rr6204.pdf.
In November 2015, FDA licensed Fluad (aIIV, CSL Seqirus), an MF59-adjuvanted inactivated influenza vaccine, for people age 65 years and older. Fluad is the first adjuvanted influenza vaccine marketed in the U.S. An adjuvant is a substance added to a vaccine to increase the immune response to vaccination. The MF59 adjuvant is based on squalene, an oil that occurs naturally in many plants and animals. Fluad has been used in Europe since 1997 and is approved in many other countries. In contrast to Fluzone High-Dose (HD-IIV, Sanofi), Fluad is a standard-dose vaccine, containing 15 mcg of hemagglutinin per virus per dose.
Yes, you should report administration of the RSV preventive antibody products (nirsevimab [Beyfortus, Sanofi] and clesrovimab [Enflonsia, Merck]) to your state immunization information system (IIS, or “registry”) as you would report vaccine administration. Contact your state immunization program if you have specific questions about reporting to your state immunization information system.
Periodically verify whether you are using the most current available documents by checking Immunize.org’s regularly updated Checklist of Current Versions of U.S. COVID-19 Vaccination Guidance and Clinic Support Tools: www.immunize.org/catg.d/p3130.pdf. This resource is updated as needed with the dates of the most currently available materials from CDC and FDA.
Information from CDC is generally updated first on the CDC web page: Interim Clinical Considerations for Use of COVID-19 Vaccines in the United States: (www.cdc.gov/covid/hcp/vaccine-considerations/index.html).
No. Obstructive sleep apnea alone is not an indication for pneumococcal vaccination. However, people with obstructive sleep apnea may have other pulmonary conditions (such as chronic obstructive pulmonary disease) that would put them at increased risk for invasive pneumococcal disease, for which they should be vaccinated.
HPV vaccine should be stored at refrigerator temperature between 2°C and 8°C (36°F and 46°F). The vaccine must not be frozen and must not be used if it has been frozen. Protect the vaccine from light. Administer as soon as possible after being removed from refrigeration. The manufacturer package insert contains additional information and can be found at https://www.immunize.org/official-guidance/fda/pkg-inserts/. For complete information on vaccine storage and handling best practices and recommendations, please refer to CDC’s Vaccine Storage and Handling Toolkit at www.cdc.gov/vaccines/hcp/admin/storage/toolkit/storage-handling-toolkit.pdf.
Yes. Acyclovir, famciclovir, and valacyclovir are antiviral drugs that are active against herpesviruses. These drugs will have no effect on Shingrix, which is a recombinant vaccine that does not contain live varicella virus.
As with all vaccines, a severe allergic reaction (for example, anaphylaxis) to a vaccine component or to a prior dose is a contraindication to further doses of that vaccine. A moderate or severe acute illness is a precaution; vaccination should be deferred until the person’s condition has improved. Because MenACWY is an inactivated vaccine, it can be administered to people who are immunosuppressed as a result of disease or medications; however, response to the vaccine might be less than optimal.
There is no need to restart the series. Give the second dose of HepB now and be sure there are at least 8 weeks between that dose and the third dose. Increasing the interval between the first two doses has little effect on immunogenicity or final antibody concentration. The third dose confers the maximum level of seroprotection but acts primarily as a booster and appears to provide optimal long-term protection. Longer intervals between the last two doses result in higher final antibody levels but might increase the risk for acquisition of HBV infection among people who have a delayed response to vaccination. No differences in immunogenicity have been observed when one or two doses of hepatitis B vaccine produced by one manufacturer are followed by doses from a different manufacturer.
Yes. Tdap vaccination is routinely recommended to be given at 27 through 36 weeks’ gestation during every pregnancy. This CDC recommendation is endorsed by the American College of Obstetricians and Gynecologists (ACOG), the American College of Nurse-Midwives (ACNM), the American Academy of Pediatrics (AAP), and the American Academy of Family Physicians (AAFP). Tdap given during one pregnancy will not provide sufficient protection for subsequent pregnancies. In June 2011 ACIP first voted to recommend that pregnant people who have never received the Tdap vaccine be vaccinated to optimize the concentration of maternal antibodies transferred to the fetus. ACIP made this recommendation with the goal of protecting newborns with maternal antibodies and decreasing the risk of transmission of pertussis to infants shortly after birth. In October 2016, ACIP voted to recommend administering Tdap vaccination early in the 27- through 36-week “window” to maximize passive antibody transfer to the infant. Mothers who have never received Tdap and who do not receive it during pregnancy should receive it immediately postpartum.
Fewer babies are hospitalized for pertussis when Tdap is given during pregnancy rather than during the postpartum period. A large U.S. study found an 85% reduction in the risk of pertussis in infants under 2 months of age whose mothers were vaccinated with Tdap at 27 through 36 weeks’ gestation, compared to infants whose mothers were vaccinated in the hospital immediately following delivery.
When a mother gets Tdap during pregnancy, maternal pertussis antibodies transfer to the newborn, protecting the baby against pertussis in early life, before the baby is old enough to have received vaccination with DTaP. Tdap also protects the mother, making it less likely that she will get infected with pertussis during or after pregnancy.
Recommendations for the use of Tdap in pregnancy are covered in detail here: www.cdc.gov/mmwr/volumes/67/rr/pdfs/rr6702a1-H.pdf, pages 22–23.
Intramuscular IG is available in single-use vials (2 mL and 10 mL). It should be administered intramuscularly, preferably in the anterolateral aspects of the upper thigh and the deltoid muscle of the upper arm. Do not use the gluteal region as an injection site because of the risk of injury to the sciatic nerve.
You cannot distinguish a mild case of varicella disease from a rash caused by the vaccine. The child may have been infected with varicella at about the same time s/he was vaccinated. The conservative approach would be to treat the child as if s/he had chickenpox and restrict her/his activities until all the lesions crust.
There is no known risk associated with MMR or varicella vaccination in someone with selective IgA or IgM deficiency. It is possible that the immune response may be weaker, but the vaccines are likely effective.
Yes. Aging decreases the body’s ability to develop a good immune response after getting influenza vaccine, which places older people at greater risk of severe illness from influenza.
After years of review and deliberation, ACIP voted in June 2022 to recommend that all adults age 65 and older should preferentially receive one of the three different vaccine products that evidence suggests are likely to perform better than standard dose, unadjuvanted vaccines: Flublok recombinant influenza vaccine (RIV, Sanofi), Fluad adjuvanted vaccine (aIIV, CSL Seqirus), or Fluzone High-Dose vaccine (HD-IIV, Sanofi). However, if none of these three vaccines is available at the time of vaccination, any age-appropriate influenza vaccine may be administered.
For a thorough review of the evidence for this recommendation, see the 2022 ACIP recommendations for influenza vaccination: www.cdc.gov/mmwr/volumes/71/rr/pdfs/rr7101a1-H.pdf.
It is important that all healthcare providers, both prenatal and pediatric, ensure that maternal RSV vaccination status is clearly documented and communicated. Prenatal care providers and birthing hospitals should ensure maternal RSV vaccination is reported to state immunization information systems (registries) and documented in maternal and newborn health records. It is also important to provide the pregnant person with a personal record of immunization.
Failure to document and communicate maternal RSV vaccination may result in extra work for pediatric offices and families to obtain records or in unnecessary administration of an RSV preventive antibody product.
RSV vaccination is recommended only once at this time, so the history of RSV vaccination is also important information for future pregnancies when the mother would need to be counseled that RSV vaccination is not an option and the infant should receive a preventive antibody product after delivery for RSV prevention.
No. Simply administer the next dose that is currently recommended, using a vaccine from the same manufacturer, if feasible, even if previous doses in the series were an earlier formulation.
A CDC evaluation found Tdap vaccination during the third trimester of pregnancy prevents 78% of pertussis cases in infants younger than 2 months of age. These findings are similar to other studies from the United Kingdom and the United States that suggest that vaccinating the mother during pregnancy is highly effective at protecting infants against pertussis.
When infants do get pertussis, their infection is less severe if their mother received Tdap during pregnancy. A CDC evaluation found maternal vaccination is 90% effective at preventing infant hospitalization from pertussis. Another U.S. study showed that infants whose mothers got Tdap during pregnancy had a significantly lower risk of hospitalization and shorter hospital stays. That same study showed that no infants born to vaccinated mothers required intubation or died of pertussis.
Links to published research on Tdap vaccination during pregnancy are available here: www.cdc.gov/pertussis/hcp/vaccine-recommendations/pregnancy-research.html.
Yes. People with HIV infection are at high risk of pneumococcal disease. The pneumococcal vaccination recommended depends on the patient’s age and prior pneumococcal vaccines received. See CDC’s information about risk-based recommendations for pneumococcal vaccination: www.cdc.gov/pneumococcal/hcp/vaccine-recommendations/risk-indications.html.
The CDC PneumoRecs VaxAdvisor mobile app can be helpful for evaluating the needs of a specific patient. You can learn more and access the app here: www.cdc.gov/pneumococcal/hcp/vaccine-recommendations/app.html.
Yes. No safety concerns associated with vaccination have been identified in people vaccinated during pregnancy or their infants.
Yes. Although oseltamivir is an antiviral drug, it is only effective against influenza A and B viruses. Shingrix recombinant zoster vaccine does not contain live virus and will not be affected by oseltamivir.
For the 2-dose adolescent schedule, the adult dose of Recombivax HB (1.0 mL dose) is administered to adolescents age 11 through 15 years, with the second dose given 4 to 6 months after the first dose. In immunogenicity studies, antibody concentrations and end seroprotection rates (at least 10 mIU/mL of anti-HBs) were similar with the 2-dose schedule and the 3-dose schedule (0.5 mL dose). As with other HepB vaccination schedules, if administration of the 2-dose schedule is interrupted, it is not necessary to restart the series. Children and adolescents who have begun vaccination with a pediatric (0.5 mL) dose of Recombivax HB should complete the 3-dose series with this dose. If it is not clear which dose an adolescent was administered at the start of a series, the series should be completed with the 3-dose schedule. Heplisav-B, the 2-dose HepB vaccine given with a 4-week interval between doses, is licensed only for adolescents and adults beginning at age 18 years.
There is no need to wait a specific interval before giving MMR. An injectable steroid dose is not considered immunosuppressive for the purpose of vaccination decisions, and so there is no concern about safety or efficacy of MMR.
Serious adverse events from GamaSTAN IG are rare. Anaphylaxis has been reported after repeated administration to people with known immunoglobulin A (IgA) deficiency; thus, IG should not be administered to these people. IG products including GamaSTAN have been associated with the formation of blood clots (thrombosis) after administration, particularly if the patient has other risk factors for thrombosis. Patients should be counseled about this risk.
Breakthrough varicella represents replication of wild varicella virus in a vaccinated person. Although most breakthrough disease is very mild, the child is contagious and activities should be restricted to the same extent as an unvaccinated person with varicella disease.
Your practice should put procedures in place to ensure that you always give vaccines by the recommended route because data regarding safety and efficacy of alternate routes are limited.
CDC and/or ACIP guidance about vaccination by the wrong route vary depending upon the vaccine and route:
Although Fluzone High-Dose (HD-IIV) and Fluad (aIIV) are FDA-licensed for people 65 years and older, in June 2024, ACIP recommended that HD-IIV or aIIV are options for administration to people age 18 through 64 years old who have had a solid organ transplant (SOT) and are on immunosuppressive medication regimens. ACIP expressed no preference for HD-IIV or aIIV over any other age-appropriate IIV or RIV vaccines for SOT recipients.
In clinical trials of the three licensed and recommended RSV vaccines, Arexvy (GSK), Pfizer (Abrysvo), and mResvia (Moderna), mild, local injection site reactions (redness, swelling), fatigue, muscle aches, and headache were common.
CDC guidance allows for doses given up to 4 days before the recommended interval to be counted as valid – such doses do not need to be repeated. However, people should not be routinely scheduled to receive a dose earlier than recommended. Schedulers should offer appointments beginning on the date of the recommended interval or later.
Lupus alone is not an indication for pneumococcal vaccination. However, immunosuppressive medication that may be used to treat lupus could create an indication for administering pneumococcal vaccines. Also, certain complications of lupus (such as nephrotic syndrome) make a person a candidate for pneumococcal vaccination. If pneumococcal vaccination is indicated, administer either PCV20 or PCV21 alone or PCV15 followed by PPSV23 one year later. If the patient is immunosuppressed and is receiving a combination of PCV15 followed by PPSV23, consider using a minimum interval of at least 8 weeks between doses if more rapid protection from serotypes unique to PPSV23 is desired.
No. People with a history of GBS may receive any age-appropriate MenACWY vaccine.
The 2-dose Recombivax HB schedule is only approved for use in children age 11 through 15 years. A 16-year-old child would need two additional doses of pediatric HepB to complete a 3-dose series.
Shingrix (GSK) is available in two presentations: a lyophilized powder that must be reconstituted using the accompanying adjuvant solution, or a manufacturer-filled syringe (MFS) that does not require reconstitution before administration.
If using the presentation that must be reconstituted, reconstitute Shingrix using only the adjuvant solution provided with the vaccine antigen. After reconstitution, administer Shingrix immediately by the intramuscular route or store the reconstituted vaccine refrigerated between 2° and 8°C (36° and 46°F) and use within 6 hours. Discard reconstituted vaccine if not used within 6 hours or if frozen. If Shingrix is reconstituted with other than the supplied adjuvant solution, it should be repeated. The dose can be repeated immediately. There is no interval that must be met between these doses.
Yes. If there is no written documentation that she received a dose of Tdap prior to or during pregnancy, a dose of Tdap should be administered to her immediately postpartum.
Yes. Pregnancy or lactation is not a contraindication to IG administration if clearly needed.
Available data suggest that healthy children are unlikely to transmit vaccine virus. Transmission of vaccine virus to a household contact has rarely been documented. It appears that transmission of vaccine virus occurs mostly, or perhaps even exclusively, when the vaccinated person develops a rash following vaccination.
Yes. MMR and varicella vaccines should be given to the healthy household contacts of immunosuppressed children.
In general, if the error is discovered on the same clinic day, you can administer the other “half” of the dose on that same day. If the error cannot be corrected on the same day, the dose should not be counted, and then the person should be recalled to the office and given a full age-appropriate repeat dose.
There are, however, two exceptions to the general rule: (1) If a patient sneezes after receiving nasal-spray live attenuated influenza vaccine, count the dose as valid. (2) If an infant regurgitates, spits, or vomits during or after receiving oral rotavirus vaccine, count the dose as valid.
If you give more than an age-appropriate dose (e.g., an adult HepA vaccine to a child), count the dose as valid and notify the patient/parent about the error. Using larger-than-recommended dosages can be more likely to result in side effects because of excessive local or systemic concentrations of antigens or other vaccine constituents. Avoid such errors by checking the vaccine vial label 3 times.
No, and this is not recommended.
In the clinical trials of both RSVPreF3 (Arexvy, GSK) and RSVpreF (Abrysvo, Pfizer) vaccines, a small number of inflammatory neurologic events, including GBS, were reported after RSV vaccination. Further FDA studies presented to the ACIP in October 2024 suggest a small increased risk of GBS of a similar magnitude for both products, approximately 7-9 excess cases per 1 million doses given. No cases of GBS or other inflammatory neurologic events were reported after mRNA RSV (mResvia) vaccination during the clinical trials. CDC and FDA continue to actively monitor the safety of all of these vaccines through national safety surveillance systems.
Estimates presented to ACIP in October 2024 comparing the benefit of RSV vaccination in the older adult population for whom it is recommended to the small increased risk of GBS following Arexvy or Abrysvo show that vaccination of a million people would prevent thousands more hospitalizations and hundreds more deaths than the small number of GBS cases vaccination may trigger. Because the benefits of preventing RSV in the recommended population far outweigh the potential risk of GBS, no changes to recommendations have been made.
In this specific situation, a child age 6 months–23 months who received one 2024–2025 Formula Pfizer-BioNTech COVID-19 vaccine dose should receive 2 doses of Spikevax (Moderna) vaccine to complete the initial series.
Refer to the schedule tables on the CDC website (www.cdc.gov/covid/hcp/vaccine-considerations/routine-guidance.html#cdc_clinical_guidance_recomm_key-table-1-2025–2026-covid-19-vaccination-schedule-november-4-2025) or on the Immunize.org standing orders template for children age 6 months through 11 years (www.immunize.org/wp-content/uploads/catg.d/p3140a.pdf) for specific dosing intervals.
Recommendations vary among adults depending upon age, pneumococcal conjugate (PCV) or polysaccharide (PPSV) vaccination history (including PCV13, PCV15, PCV20, PCV21, and PPSV23), and pneumococcal vaccine products available:
