Infectious Disease Crisis in America: The Vaccination Policy Fallout
Infectious Disease Crisis in America: The Vaccination Policy Fallout
A comprehensive analysis of measles, pertussis, and vaccine-preventable disease trends since January 2025 — with comparisons to G7 nations and local impact on California & San Joaquin County • Published March 18, 2026
Key Findings
The United States is experiencing its worst measles outbreak in 35 years and a sustained pertussis surge, driven by declining vaccination rates and unprecedented federal actions to weaken childhood vaccine recommendations. Since January 20, 2025, more than 3,600 confirmed measles cases have been reported across 46 states, with 4 deaths and an 11% hospitalization rate. The Trump administration, under HHS Secretary Robert F. Kennedy Jr., gutted the childhood vaccine schedule from 18 to 11 recommended diseases, fired all expert ACIP members, terminated $500 million in vaccine research, and altered CDC messaging to suggest a link between vaccines and autism. A federal judge blocked these changes on March 16, 2026, ruling they likely violated federal law. Meanwhile, California has emerged as the strongest state-level counterweight, but San Joaquin County faces a “very high risk” rating for measles due to only 60% of children under 5 being vaccinated.
Jan 2025 – Mar 12, 2026
since January 2025
cases in 2025
(down from 95.2% in 2019–20)
The National Measles Crisis
From January 1, 2025 through March 12, 2026, there were 3,637 confirmed measles cases across 46 states and jurisdictions. About 93% were in people who were unvaccinated or had unknown vaccination status. The CDC confirmed three deaths — two unvaccinated children in Texas and an unvaccinated adult in New Mexico — plus one additional child death confirmed by the Los Angeles County Department of Public Health.
In 2025 alone, the U.S. recorded 2,284 confirmed measles cases, the highest annual total since 1992 and by far the most since the disease was declared eliminated in 2000. Of those, 11% required hospitalization. Measles has been continuously circulating in the U.S. for more than a year, starting with a Texas outbreak (January–August 2025), followed by ongoing outbreaks on the Utah-Arizona border and in South Carolina.
The trajectory in 2026 is even worse: in the first 10 weeks alone, there were more than 1,362 confirmed cases — nearly 60% of the entire 2025 total. South Carolina alone has reported 997 cases centered in Spartanburg County as of March 17, 2026, the worst single-state outbreak since elimination was achieved.
U.S. Confirmed Measles Cases by Year (2019–2026)
Sources: CDC. 2026 data through March 12 (1,362 cases in ~10 weeks); projection annualized at current pace.
The Elimination Status at Risk
The United States achieved measles elimination status in 2000 from the Pan American Health Organization (PAHO). That status is now in serious jeopardy. PAHO will evaluate U.S. measles data in April 2026, and many experts believe the designation will be revoked. Canada lost its measles elimination status in November 2025 after sustained outbreaks, and the UK lost its status in January 2026. The key question is whether the ongoing outbreaks in Texas, Utah-Arizona, and South Carolina represent linked chains of transmission exceeding 12 months of continuous spread — the threshold for losing elimination status.
The Whooping Cough (Pertussis) Surge
The pertussis picture is equally alarming. In 2025, there were 28,783 cases of whooping cough in the U.S., following 43,321 in 2024 — the highest in over a decade. For comparison, there were just 7,063 cases in 2023. At least 13 people died of pertussis in 2025.
Among infants in the first six months of life who contract pertussis, roughly 50% require hospitalization and about 10% die. Only 79% of children born in 2021 had received four DTaP shots by age two, well below levels needed for community protection.
Why Pertussis Is Especially Dangerous for Infants
Babies with whooping cough may stop breathing for 20+ seconds at a time, turning blue as the diaphragm cannot recover between violent coughing fits. Complications include pneumonia, seizures, chronic lung disease, brain damage from oxygen deprivation, and death. There is no specific treatment once infection takes hold — only supportive care and antibiotics to prevent further spread. Vaccination during pregnancy (Tdap at 27–36 weeks) is approximately 90% effective at preventing infant hospitalization.
The Vaccination Rate Collapse
The underlying driver is clear: MMR vaccination coverage among U.S. kindergartners dropped from 95.2% during the 2019–2020 school year to 92.5% in 2024–2025, leaving approximately 286,000 kindergartners at risk. That 2.7 percentage-point decline breaches the critical 95% herd immunity threshold for measles.
Since 2019, more than two-thirds of counties have reported drops in vaccination rates. Among states that track MMR rates, 67% of their counties fall below the level needed to stop a measles outbreak. Vaccine exemptions increased to 3.6% nationally, with 17 states exceeding 5% exemption rates. Sixteen states now report kindergarten MMR rates below 90%.
U.S. Kindergarten MMR Vaccination Rate vs. Herd Immunity Threshold
Source: CDC SchoolVaxView, KFF analysis. 95% is the WHO-recommended threshold for measles herd immunity.
Federal Policy Actions Under the Trump/Kennedy HHS
The administration took several concrete steps that public health experts say worsened the crisis:
May 2025
CDC revised COVID-19 vaccination guidance, removing recommendations for routine immunization for healthy children and pregnant women.
June 2025
Kennedy fired all 17 members of the Advisory Committee on Immunization Practices (ACIP) and replaced them with individuals sympathetic to his views, some associated with anti-vaccine organizations.
September 2025
Kennedy promoted unproven ties between Tylenol, vaccines, and autism in an Oval Office event with President Trump.
November 2025
CDC website updated to suggest — without scientific evidence — that studies have not ruled out the possibility that infant vaccines cause autism.
December 2025
CDC dropped the long-held recommendation that all newborns be vaccinated against hepatitis B, despite no new evidence questioning the vaccine’s safety. HHS also terminated $500 million in mRNA vaccine research contracts.
January 5, 2026
CDC announced unprecedented overhaul of the childhood vaccine schedule, reducing routine recommendations from 18 diseases to 11. The changes were modeled after Denmark’s schedule and were not based on any new scientific evidence or recommendation from a lawfully constituted ACIP.
January–February 2026
28 states rejected the new CDC schedule. The AAP published its own competing 2026 schedule covering 18 diseases and formally broke with the CDC for the first time in history.
March 16, 2026
A federal judge issued a preliminary ruling blocking the schedule changes, finding Kennedy’s reconstitution of ACIP and the vaccine schedule overhaul likely violated the Administrative Procedure Act.
G7/G8 Comparison: The U.S. Diverges From Peer Nations
While measles surged globally in 2023–2024, peer nations responded with aggressive vaccination campaigns. The U.S. went the other direction — and it shows in the data.
Measles Cases Per Million Population: G7 Nations (2025 Full Year and 2026 Annualized)
Sources: CDC, UKHSA, ECDC, WHO, Japan JIHS. 2026 annualized from partial-year data. UK = England only. Some 2026 data not yet available for all nations.
| Country | 2025 Cases | 2026 Pace | Trend | Deaths (2025) |
|---|---|---|---|---|
| United States | 2,284 | ~7,000+ (annualized) | ▲ Worsening sharply | 3 confirmed |
| France | ~821 (12-mo period) | Low (12 in Jan 2026) | ▼ Declining | 4 |
| UK (England) | 959 | ~1,400 (annualized) | ▼ Declining from 2024 peak | 1 |
| Italy | 538 (12-mo period) | ~1,000 (annualized from 84 in Jan) | ▲ Mixed | 0 |
| Germany | ~100 (estimated) | Data pending | Stable / low | 0 |
| Canada | 5,000+ | Declining after campaigns | ▼ Improving | 0 |
| Japan | ~200 (est. full year) | Data pending | Low / contained | 0 |
Sources: CDC, ECDC, UKHSA, WHO, Japan JIHS. Some figures are 12-month reporting periods (Feb 2025–Jan 2026). Case counts may differ between provisional and final reports.
The Critical Divergence
The WHO European Region reported 33,998 measles cases in 2025 — a 75% drop from 127,412 in 2024. Europe’s trend is sharply downward thanks to emergency vaccination campaigns. The U.S. trend is sharply upward. Between 2001 and 2011, 40% of U.S. measles cases came from international travelers. In 2025, only 12% were imported — meaning the vast majority now represent homegrown, domestic transmission.
California: A Firewall State With Vulnerabilities
California has positioned itself as the most aggressive state-level counterweight to the federal retreat from public health science, but it is not immune to national trends.
California’s Policy Response
- Multi-state lawsuit (February 2026): Governor Newsom announced California is co-leading a 15-state lawsuit against Kennedy, HHS, and the CDC, arguing the January schedule changes violate federal law.
- AB 144 (September 2025): Newsom signed legislation empowering CDPH to set its own immunization schedules based on major professional medical societies (like the AAP) rather than the politicized CDC. The law also requires California insurers to cover all authorized vaccines at no cost.
- First state to join WHO network: California became the first U.S. state to join the WHO’s Global Outbreak Alert & Response Network after the Trump administration pulled the U.S. from WHO.
- West Coast Health Alliance: California, Oregon, Washington, and Hawaii formed an alliance to provide coordinated, science-based vaccine guidance independent of federal recommendations.
- Hired former CDC leaders: The state engaged former CDC Director Susan Monarez and former CDC Chief Medical Officer Debra Houry to lead the new Public Health Network Innovation Exchange (PHNIX).
California Disease Numbers
in California (as of Mar 16, 2026)
through April 2025 alone
(above 95% herd threshold)
(up from 644 in 2023)
Measles: As of March 16, 2026, there have been 29 confirmed measles cases reported in California, with two localized outbreaks active. In 2025, the state had 25 cases (up from 15 in 2024 and 4 in 2023). While far lower per capita than the national rate, cases are climbing. The state’s strong school vaccine mandate (SB 277, eliminating personal belief exemptions in 2016) provides a significant buffer.
Whooping cough: The CDC reported 590 pertussis cases in California through late April 2025, already eclipsing the full 2024 total. California saw over 2,000 pertussis patients in the last 10 months of 2024 alone, including 62 infant hospitalizations and one infant death — a roughly 500% increase over 2023. UC Davis infectious disease experts called California “one of the hot spots in the country.”
Kindergarten vaccination: MMR coverage among California kindergartners statewide has exceeded 95% since at least 2016–17. However, 16 of 58 counties (28%) report rates below 95%, and 5 counties fall below 90%. There is significant regional variation.
San Joaquin County: Local Risk Assessment
Current Status
San Joaquin County’s last confirmed measles case was in March 2024 — a child exposed overseas before arriving in the U.S. There have been no locally transmitted measles cases in the county during the current national surge. The county’s public health department has also identified two presumptive cases of H5N1 avian influenza in individuals who had contact with infected dairy cattle, highlighting the breadth of infectious disease monitoring needed.
Vaccination Data: A Two-Tiered Picture
San Joaquin County Vaccination Rates: Kindergarten vs. Under-5 Population
| Metric | San Joaquin County | Sacramento County | Stanislaus County | CA Statewide | National |
|---|---|---|---|---|---|
| Kindergarten MMR (2+ doses, 2023–24) | 96.3% | 96.4% | 96.6% | 96.2% | 92.5% |
| Under-5 MMR vaccination rate | 59.99% | 68.32% | 65.52% | N/A | N/A |
| Measles risk rating (ABC News) | Very High | Higher Risk | Higher Risk | — | — |
| Last confirmed measles case | March 2024 | June 2025 | N/A | — | — |
Sources: CDPH Kindergarten Immunization Assessment 2023–24, ABC News / Nature Health, ABC10.
Why San Joaquin County Is Vulnerable
The gap between the kindergarten rate (96.3%, above herd threshold) and the under-5 rate (about 60%) is the critical vulnerability. It means there is a large population of toddlers and preschoolers who have not yet completed their vaccine series — and they are the most medically vulnerable group for severe measles complications.
Several additional risk factors compound this exposure:
- Population mobility: San Joaquin County is a commuter county with massive daily flows to the Bay Area and Sacramento, increasing the chance of imported cases.
- International travel: Significant immigrant communities where international travel may bring imported cases from countries experiencing outbreaks.
- Healthcare access: Agricultural communities where healthcare access can be uneven, particularly for migrant and seasonal workers.
- Regional proximity: Sacramento County confirmed measles in June 2025; Bay Area counties (San Mateo, Napa, Santa Clara) have all confirmed 2026 cases. Measles virus is now active in the broader region.
What South Carolina Teaches Us
South Carolina’s outbreak grew from a handful of cases in September 2025 to 997 by March 17, 2026, centered in Spartanburg County’s private Christian academies with largely unvaccinated student bodies. A single introduction into an under-vaccinated community can produce hundreds of cases within months. With only 60% of children under 5 vaccinated in San Joaquin County, the conditions for rapid community spread exist if a case enters the right setting.
What Dr. Maggie Park Says
Dr. Maggie Park, San Joaquin County’s public health officer, told Stocktonia News that there isn’t any reason for immediate alarm but strongly recommended getting vaccinated, noting: “Measles rates have been very low across the nation for many years, and now we’re seeing a resurgence of measles because of vaccination rates that are falling below the desired rates in portions of the country.”
The Bottom Line
At every level of analysis, the same pattern holds:
Nationally: The U.S. is experiencing its worst measles outbreak in 35 years and its worst pertussis in over a decade, with declining vaccination rates and an administration that actively undermined vaccine confidence before a federal court intervened.
Internationally: The U.S. is the only G7 nation whose government responded to measles outbreaks by reducing vaccine recommendations. Every other peer nation intensified vaccination campaigns, and most are seeing declining case counts.
California: The state’s strong vaccine laws and aggressive pushback against federal schedule changes provide a significant buffer. But statewide averages mask local vulnerabilities, and the state is seeing its own surges in both measles and pertussis.
San Joaquin County: The “very high risk” rating for under-5 measles vaccination is the most immediate local concern. The kindergarten rate is good, but the gap for younger children — the ones most likely to be hospitalized or die from measles — is a genuine vulnerability.
References & Sources
- CDC — Measles Cases and Outbreaks (updated March 13, 2026)
- CDC — Pertussis Surveillance and Trends
- CDC SchoolVaxView — Kindergarten Vaccination Coverage & Exemptions
- Public Health Communications Collaborative — Measles Outbreak Data (March 2026)
- WHO/UNICEF — European Measles Report (February 2026)
- ECDC — Monthly Measles & Rubella Surveillance Report
- UK Health Security Agency — England Measles Cases 2026
- Japan Institute for Health Security — Measles Epidemiological Report 2025
- HHS — CDC Acts on Presidential Memorandum (January 5, 2026)
- PBS — Judge Blocks RFK Jr. Vaccine Schedule Changes (March 16, 2026)
- STAT News — Federal Judge Stalls Kennedy’s Vaccine Policy Overhaul
- NBC News — RFK Jr. Overhauls Childhood Vaccine Schedule
- KFF — Kindergarten Routine Vaccination Rates Continue to Decline
- Contagion Live — Will the U.S. Lose Measles Elimination Status?
- California Dept. of Public Health — Measles Data
- Governor Newsom — California Multi-State Vaccine Lawsuit (February 2026)
- KQED — California AB 144 Vaccine Law (September 2025)
- Stocktonia — Is San Joaquin County Safe From Measles?
- ABC10 — ABC News Measles Risk Map: Sacramento Area Counties
- South Carolina DPH — 2025–2026 Measles Outbreak Data
- NBC News — Measles Outbreaks Could Cost $1B+ Annually
- The Conversation / Brown University — Measles Resurgence Analysis (March 2026)
Report compiled by Lodi411.com • Data current as of March 18, 2026 • Contact: info@lodi411.com