The Vaccine Intelligence Report: April 29-May 5

The Vaccine Intelligence Report—brought to you by Vaccinate Your Family—provides clear, fact-based updates on vaccine policy, research, and public health each week. This report is part of Viral Truths, a resource designed to cut through the noise, offering concise information to help navigate the evolving immunization landscape.

THIS WEEK AT A GLANCE

  • HHS leadership continues to evolve: Trump nominated Nicole Saphier for Surgeon General, and the FDA named Katherine Szarama as Acting Director of CBER (the agency’s vaccine center), replacing Vinay Prasad
  • The DOJ appealed a preliminary injunction that blocked several of Kennedy’s vaccine policy changes as AAP’s lawsuit against HHS proceeds, though the government did not provide a rationale for the appeal
  • An independent evidence review including more than 270 studies reaffirmed the safety and effectiveness of HPV vaccination
  • States including Missouri, Tennessee, and Rhode Island continue to advance and debate vaccine-related legislation, while Connecticut moved to dismiss a lawsuit over its repeal of religious exemptions for school immunization requirements
  • The U.S. is approaching 2,000 measles cases in 2026 as the CDC warns of an anticipated surge amid spring and summer travel
  • The U.S. respiratory illness season is coming to an end, but rotavirus activity remains elevated
  • New research highlights how both media consumption patterns and inconsistent CDC public health messaging may be shaping vaccine hesitancy and eroding trust in vaccines

NEED TO KNOW

Administration Announces Latest HHS Leadership Picks Amid Ongoing Turnover

  • Over the past week, the Administration has announced several new Department of Health and Human Services (HHS) leadership appointments—the latest in a period of sustained turnover throughout HHS.
  • On Thursday (Apr. 30) Trump announced his nomination of Dr. Nicole Saphier—a practicing radiologist and former Fox News Contributor—for the position of Surgeon General.
  • While Saphier has expressed support for vaccines, specifically pointing to the importance of measles and polio vaccines, she has also questioned aspects of the childhood vaccine schedule—including the hepatitis B birth dose and Covid vaccines for children—and has taken a public stance opposing mandates.
    • Saphier is widely viewed as more likely to secure Senate confirmation than prior nominees due to her clinical credentials and public communication experience, though her views on vaccine policy and broader public health approaches are expected to face scrutiny.
    • This is Trump’s third nominee for the role, following the withdrawal of Dr. Janette Nesheiwat amid questions about her credentials and the failed nomination of Casey Means, M.D. who faced bipartisan concerns about her qualifications and views on public health.
  • Separately, Katherine Szarama has been named Acting Director of the Food and Drug Administration’s (FDA) Center for Biologics Evaluation and Research (CBER), which oversees products including vaccines, gene therapies, and blood supply.
    • Szamara, who recently joined the FDA as deputy to former Director Dr. Vinay Prasad, is expected to serve on a temporary basis while the search for a permanent director continues.
    • Her appointment follows a tumultuous period for CBER leadership, including Prasad’s departure after a series of controversial decisions related to drugs and vaccines.
  • Last week (Apr. 30) the Administration also appointed Dr. Sara Brenner as Senior Counselor for Public Health at HHS—a role that does not require Senate confirmation—and will serve as a key liaison between Secretary Kennedy and federal health agencies.
    • Brenner previously served as a senior FDA official—she is seen as aligned with MAHA priorities and has expressed skepticism about vaccines.

DOJ Appeals Ruling Blocking HHS Vaccine Policy Changes

  • The Trump Administration has appealed a March 16 ruling that paused several vaccine policy changes implemented by Secretary Kennedy.
    • The lawsuit—brought by the American Academy of Pediatrics (AAP), other medical societies, and additional plaintiffs—argues that the changes to the federally recommended childhood immunization schedule and the reconstitution of the Advisory Committee on Immunization Practices (ACIP) were unlawful.
    • The court issued a temporary injunction restoring the Centers for Disease Control and Prevention’s (CDC) July 2025 immunization schedule and blocking the appointment of new members to ACIP. The ruling found plaintiffs were likely to succeed in their claims that the Administration’s actions violated federal law.
  • The Department of Justice (DOJ) has not publicly detailed the legal basis for its appeal, which will be heard by the U.S. Court of Appeals for the First Circuit.
    • Additionally, the Administration also sought to pause the case while the appeal proceeds, but last week (May 1), a federal court denied that request—leaving the injunction in place and ACIP unable to meet.
  • The move follows recent changes to ACIP’s charter, which broaden member qualification criteria and place greater emphasis on evaluating potential harms from vaccination. Though separate from the lawsuit, plaintiffs argue these changes are part of a broader effort to undermine ACIP’s role and established vaccine policy processes.
  • The appeal adds to ongoing uncertainty around federal vaccine guidance, as legal challenges continue to shape whether—and how—the Administration can modify ACIP and the recommended immunization schedule.

Evidence Review Reaffirms HPV Vaccines as Safe and Highly Effective

  • An independent evidence review of human papillomavirus (HPV) vaccination published Tuesday (May 5) reaffirms the vaccines’ strong safety and effectiveness profile.
    • The Vaccine Integrity Project (VIP)—an initiative of the University of Minnesota’s Center for Infectious Disease Research and Policy (CIDRAP)—conducted a meta-analysis of 274 studies assessing the safety, effectiveness, and immunogenicity (a vaccine’s ability to provoke an immune response) of HPV vaccines available in the U.S.
    • HPV is a very common infection. While infection clears on its own in most people, it can cause cancer. In the U.S., HPV is responsible for approximately 90% of cervical and anal cancers, as well as most cancers of the vagina, vulva, penis, and oropharynx (the middle part of the throat).
  • The review found that HPV vaccination reduces the risk of cervical cancer by 80% among women vaccinated before age 16 and by 66% among those vaccinated after 16. Protection was shown to last at least 16 years following vaccination.
    • The findings align with broader population-level trends. A recent American Cancer Society (ACS) study reported that U.S. cervical cancer rates among women ages 20–31 declined by 27% from 2000–2005 to 2016–2021—following the introduction of HPV vaccines in 2006.
  • Importantly, the review found no association between HPV vaccination and serious adverse events, including pregnancy complications, neurological conditions, or long-term health risks.
  • The findings add to a substantial body of evidence supporting HPV vaccination as a safe and effective tool for preventing multiple cancers and reducing disease burden over time.

STATE POLICY SPOTLIGHT

States Continue Action on Bills Aiming to Change Vaccine Policy

  • Missouri SB 878 advanced out of the House Rules Committee on May 4 and now moves toward consideration by the full House. The bill would amend regulations to specify which vaccines pharmacists can order and administer.
  • Tennessee Governor Bill Lee signed two vaccine related bills as the state closed out its legislative session.
    • SB 2070 (signed April 21) prohibits insurers from penalizing clinicians for treating patients who decline vaccinations, including through reimbursement or network participation policies. The law will take effect July 1.
    • HB 2659 (signed May 1) expands hospital requirements to offer influenza (flu) and pneumococcal vaccines to a broader group of adult patients prior to discharge, increasing opportunities for vaccination.
  • In Rhode Island, SB 2856 was recommended to be held for further study by committee on April 30, effectively pausing the bill for the remainder of the session. The bill would expand pharmacists’ ability to administer all routine, recommended childhood vaccines to children ages 3–18 with parental consent and would require reporting to the state.

Connecticut Moves to Dismiss Lawsuit Over Religious Vaccine Exemptions

  • Connecticut officials are seeking to dismiss an ongoing lawsuit challenging the state’s 2021 repeal of religious exemptions for school vaccination requirements, following recent changes to state law.
    • The lawsuit, brought by several families, argues that eliminating the exemption violated religious freedom protections under the state’s Religious Freedom Restoration Act and was scheduled to go to trial in May.
  • In April, lawmakers amended the state’s religious freedom law to explicitly exclude school immunization requirements, a change signed off on by Governor Ned Lamont and designed to address the legal challenge.
  • State officials argue the change renders the case moot and have requested additional time to file a motion to dismiss, with plaintiffs agreeing to delay proceedings while the court considers next steps.

OUTBREAK OUTLOOK

News on respiratory virus season, measles, pertussis, and other vaccine-preventable and infectious disease outbreaks.

Number of Measles Cases Continues to Climb, CDC Warns of Potential Surge as Travel Season Begins

  • As of May 1, the U.S. has reported 1,923 measles cases in 2026—an increase of 46 cases in the last week.
  • The CDC sent a letter to state and local health departments last week (Apr. 27) issuing measles guidance for the upcoming season.
    • The CDC says it expects to see increases in measles cases coinciding with heightened international and domestic travel and large events during the spring and summer months.
    • The letter urges state and local health departments to report measles cases to the CDC within 24 hours, conduct active surveillance to identify additional suspected cases, and enhance outreach to under-vaccinated communities through trusted messengers. The letter also promotes CDC’sBe Ready for Measles toolkit which includes preparedness tools and communication materials.

Respiratory Season Winds Down; Study Shows Higher Pediatric Flu Vaccination Would Reduce Severe Outcomes

  • Respiratory illness activity is very low nationwide as the season winds down.
    • Flu activity continues to decline, with all states reporting low or minimal levels.
    • Six additional pediatric flu deaths were reported in the past week, bringing this season’s total to 155.
    • Respiratory syncytial virus (RSV) activity is decreasing and has peaked in most regions of the country.
  • A new study found that increasing the U.S. childhood flu vaccination coverage rate (VCR) could significantly reduce the number of flu-related hospital visits and pediatric deaths each season.
    • Modeling shows raising U.S. pediatric flu immunization rates from approximately 50% (current VCRs) to the Healthy People 2030 target rate of 70% would prevent over 2 million outpatient visits, 30,000 hospital admissions, and 123 deaths annually.
    • Despite broad availability, childhood flu VCRs have remained low in recent years, contributing to higher seasonal case counts and severe outcomes.
    • The 2024-25 season saw 297 pediatric flu deaths—the highest number on record—with vaccination coverage at just 48.8% among children 6 months through 17 years.

Studies Highlight Role of Information Sources and Messaging in Shaping Vaccine Trust

  • A recent Johns Hopkins University survey of nearly 3,000 U.S. adults found that measles, mumps, and rubella (MMR) vaccine hesitancy is closely associated with individuals’ media habits, with information sources playing a significant role in shaping attitudes toward vaccination.
    • The study found that individuals who rely on nontraditional or non-medical information sources—including certain online and alternative media—were significantly more likely to report hesitancy compared to those who rely on healthcare professionals and mainstream medical sources.
    • The findings underscore that trust in physicians and public health institutions remains strongly associated with lower hesitancy, underscoring the importance of trusted messengers in vaccine decision-making.
  • A separate analysis finds that recent CDC communication around vaccines—particularly messaging related to autism—may be contributing to confusion and declining public trust.
    • The study points to inconsistent or unclear messaging as a factor that can amplify uncertainty, especially when it appears to revisit questions that have already been extensively studied and resolved.
    • Researchers warn that such communication may reinforce falsehoods. They emphasize the need for clear, consistent, and evidence-based messaging to maintain confidence in vaccines.

REALITY CHECK

These fact checks respond to several recent claims made by different groups and individuals.

CLAIM: The childhood vaccine schedule should be more flexible, as there is no significant harm in delaying or adjusting the timing of pediatric vaccinations.

  • REALITY: This is incorrect—the current pediatric vaccine schedule recommended by the CDC and other leading medical organizations has been carefully developed over decades based on extensive clinical trials, epidemiological data, and real-world evidence. It is designed to provide the most effective protection to children at the ages when they are most vulnerable to serious disease and also equip their immune systems to respond to potential future exposures.
  • The timing of vaccines is not arbitrary and is basedon when children are most likely to be exposed to disease and when vaccines produce the strongest protective immune response, meaning delays leave gaps in protection.
  • Many vaccine-preventable diseases pose the greatest risk in early childhood, when children are more susceptible to severe complications—delaying vaccination prolongs the period they remain unprotected.
    • For example, a study published in JAMA Pediatrics found that children whose vaccinations were delayed were significantly more likely to develop pertussis (whooping cough)—a highly contagious respiratory infection that can cause breathing difficulties, pneumonia and even death in infants—compared to those who were vaccinated on time.
  • Delaying vaccines can also lead to widespread and otherwise preventable disease outbreaks, particularly in settings like schools and daycares, where unprotected children can facilitate transmission.
  • Further, there is no evidence that alternative or delayed schedules improve safety or provide any medical benefit and spreading out vaccines may increase the number of medical visits and the risk that children will miss doses and remain unprotected.
  • Childhood vaccines are among the most rigorously studied and continuously monitored medical products, and following the AAP-recommended or the reinstated CDC schedule is the best way to ensure children are most effectively protectedagainst serious disease.

CLAIM: Gavi—the international humanitarian organization—uses antiquated vaccines that contain thimerosal (mercury), which is a dangerous ingredient and should no longer be used.

  • REALITY: Thimerosal—a preservative used to prevent contamination—is one of the most thoroughly studied ingredients in vaccines, with no credible evidence showing that it causes harm.
    • Thimerosal contains ethylmercury, which is processed and cleared quickly by the body and does not accumulate to harmful levels. This differs from methylmercury—the form found in some fish—which can be toxic with high or prolonged exposure.
    • Despite claims that the thimerosal-containing pertussis (whooping cough) vaccine causes brain injury, consistent evidence shows there is no association.
  • While thimerosal has been largely phased out of vaccines in the U.S., it continues to be used in many low- and middle-income countries (LMICs) due to practical considerations related to delivery, access, and protection.
    • Thimerosal is primarily used in multi-dose vialsto prevent contamination. These vials are more cost-effective and easier to distribute in settings with limited cold-chain capacity. Single-dose vials that don’t require thimerosal are significantly more expensive and logistically challenging to deploy at scale.
    • In some cases, thimerosal-containing vaccines support more efficient immunization strategies, including fewer doses or longer-lasting protection—important in areas where access to healthcare may be limited.
  • Global health experts emphasize that removing thimerosal from these vaccines would increase costs, strain supply, and complicate delivery—ultimately reducing access and leaving more children vulnerable to vaccine-preventable diseases.

WHAT TO WATCH

FDA Funding Bill Advances Amid Vaccine Oversight Concerns

  • The House Appropriations Committee advanced an FDA funding bill with a modest (~$200 million) increase, maintaining core resources that support vaccine review capacity, though it excludes a proposed expansion of user fee programs that help fund biologics evaluation.
  • Lawmakers raised concerns about the integrity of FDA’s vaccine approval process, with Democrats warning that recent agency decisions and HHS leadership could undermine the scientific standards that have historically guided vaccine review and authorization.

Schrier Introduces VFC Legislation to Reinforce Pediatric Vaccine Access

  • FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) will meet on May 28 to review data and make recommendations on the strain composition for the 2026–2027 Covid vaccines.
  • The meeting will be public and virtual, with opportunities for stakeholder input and public comment though the advisory committee’s recommendations are non-binding.

Bipartisan Senate Appropriators Urge State Department to Restore Gavi Funding

  • Senators Susan Collins (R-ME) and Jeanne Shaheen (D-NH) have sent a letter to Secretary of State Marco Rubio requesting the release of $600 million in appropriated funds the Administration is withholding from Gavi.
  • The funds will expire on September 30 if they are not released.

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