Safety of MMR vaccination evaluated in children with food and gelatin allergy in Iran

Mehdi Shokri; Masoud Movahedi; Nima Parvaneh; Mohammad Gharagozlou; Mohadese Sadat Mousavi Khorshidi; Muhadese Mahdavi; Fatemh Alizadeh

doi:10.1186/s12887-025-05666-w

Safety of MMR vaccination evaluated in children with food and gelatin allergy in Iran

BMC Pediatr. 2025 Apr 23;25(1):318. doi: 10.1186/s12887-025-05666-w.

Authors

Mehdi Shokri^{1

2}, Masoud Movahedi³, Nima Parvaneh³, Mohammad Gharagozlou³, Mohadese Sadat Mousavi Khorshidi⁴, Muhadese Mahdavi⁵, Fatemh Alizadeh⁶

Affiliations

¹ Department of Pediatrics, School of Medicine, Imam Khomeini Hospital, Ilam University of Medical sciences, Ilam, Iran. mehdishokrii1991@gmail.com.
² Clinical Research Development Unit, Imam Khomeini Hospital, Ilam University of Medical Sciences, Ilam, Iran. mehdishokrii1991@gmail.com.
³ Division of Allergy and Clinical Immunology, Department of Pediatrics, Children's Medical Center Hospital, Tehran University of Medical Sciences, Tehran, Iran.
⁴ Division of Allergy and Clinical Immunology, lolagar hospital, Tehran University of Medical Sciences, Tehran, Iran.
⁵ Department of Clinical Allergy, Imam Khomeini Hospital, Amol Campus of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
⁶ Allergy and Clinical Immunology Department, Iran University of Medical Sciences, Tehran, Iran.

Abstract

Background: Vaccination is essential for building immunity across various populations, and governments consider it a cornerstone of public health. This study aims to investigate the prevalence of gelatin allergy among infants with food allergies who have received previous vaccinations and were referred to this center for Measles-Mumps-Rubella (M.M.R.) vaccine administration.

Methods: This study, conducted at the Immunology Children's Medical Center (CMC) Hospital in Tehran, Iran, aimed to explore the prevalence of gelatin allergy in infants with food allergies undergoing M.M.R vaccine injections. The cross-sectional study included children diagnosed with food allergies, confirmed by allergy specialists, and who provided consent. The methodology involved different tests based on the severity of food allergies. For children with mild food allergies, a gelatin prick test preceded MMR vaccination. Those with severe food allergies or a history of vaccine reactions underwent skin prick tests with various gelatins and the MMR vaccine. Positive results led to graded dose vaccinations. Data, including clinical questions, were recorded using a standard vaccination questionnaire.

Results: Results from 163 evaluated children (average age: 16.85 months) revealed that 8% were allergic to gelatin. Notably, all gelatin-allergic patients had a positive family history of atopia. A significant association existed between gelatin allergy and a positive intradermal vaccine test. No significant relationships were found with gender, age, food allergens, infant milk type, antihistamine use, blood history, or product use.

Conclusion: The study concludes that a gelatin-free vaccine is preferable for allergic patients. In cases where such a vaccine isn't available, a skin test with the vaccine is recommended before full-dose administration. The findings emphasize the importance of considering family history and intradermal vaccine tests in managing gelatin allergies during vaccinations.

Keywords: Allergy; Gelatin; MMR vaccination.

MeSH terms

Child, Preschool
Cross-Sectional Studies
Female
Food Hypersensitivity* / complications
Food Hypersensitivity* / diagnosis
Food Hypersensitivity* / epidemiology
Gelatin* / adverse effects
Humans
Infant
Iran / epidemiology
Male
Measles-Mumps-Rubella Vaccine* / adverse effects
Prevalence
Skin Tests
Vaccination / adverse effects

Substances

Gelatin
Measles-Mumps-Rubella Vaccine