herd immunity
Coverage of herd immunity in the Nexus archive.
- ‘Measles is here’: Michigan health officials warn as vaccination rates fall dangerously low
Michigan health officials warn that measles cases have surged in 2026, surpassing 2025 totals and marking the worst year since 1991. The outbreak is linked to declining MMR vaccination rates, lax attitudes toward diseases, and misinformation on social media and political platforms. Herd immunity thresholds (95% vaccination) are not met in several counties, raising concerns about preventable outbreaks.
- US measles cases surge to 35-year high
US measles cases reached a 35-year high with 2,295 recorded this year, surpassing the total for 2025. 93% of patients are unvaccinated, and declining vaccination rates have pushed most counties below herd immunity levels. Health Secretary Robert F. Kennedy Jr., a vaccine skeptic, and President Donald Trump are mentioned in the context of shifting positions on vaccine messaging.
- Too young for the MMR shot, babies become ‘sitting ducks’ in measles outbreaks
A measles outbreak in South Carolina has left infants vulnerable due to their inability to receive the MMR vaccine before 6 months. Low vaccination rates have eroded herd immunity, leading to over 1,000 cases and threatening the U.S.'s measles-free status. Healthcare providers are administering early MMR doses to protect young children.