A new international study led by Bar-Ilan University’s Azrieli Faculty of Medicine reveals a global decline in parental trust in childhood vaccines since the COVID-19 pandemic, leading to lower immunization rates and a resurgence of measles outbreaks in Israel and the UK.

Published in Vaccine, the study surveyed over 2,000 parents and found that MMR and DTP vaccination rates dropped significantly after the pandemic. In the UK, MMR coverage fell from 97.3% to 93.6%, and in Israel from 94.3% to 91.6%. Notably, 5–6.6% of parents who vaccinated older children before COVID-19 chose not to vaccinate younger ones afterward.

Lead author Prof. Michael Edelstein warned that even small drops can undermine herd immunity, fueling outbreaks: the UK recorded 3,000 measles cases in 2024, while Israel has seen 1,800 cases and eight child deaths in 2025.

The main cause of hesitancy is fear of vaccine side effects, which has intensified post-pandemic. The study also found sharper declines among UK parents of Asian descent and in Israel’s ultra-Orthodox and Arab communities.

Researchers urge targeted communication, education, and community initiatives to rebuild trust and prevent the loss of decades of progress in disease prevention.

Bar-Ilan University is a leading Israeli research institution known for innovations in medicine, AI, sustainability, and community engagement.