Correlation Study of the Most Important Environmental Influencing Factors on the Razi MMR Vaccine.

Measles, mumps, and rubella (MMR) are among the most important viral infectious diseases in Iran and neighboring countries. After using a trivalent vaccine for these three diseases for a long time, in recent years, these diseases have been significantly controlled in Iran. One of the important points of storing the vaccine is that the vaccine strains are highly temperature-sensitive viruses. Due to tropical climatic conditions in Iran, the cold chain may not be achievable during the storage and transmission of the MMR vaccine. Therefore, the efficacy of the vaccine may be affected. This study aimed to evaluate the MMR vaccine potency at different temperatures (stress tests) and frequent light exposures. All quality control tests in the form of stability studies were performed on the samples from three consecutive batches produced during a full-scale Razi production. The samples were stored at 2-8, 22-25, 35-37, and 42-45°C in specific time intervals, exposed to frequent light, and underwent freezing/thawing conditions. According to the results, the storage of the vaccine at high temperatures caused a decrease in potency and increased moisture content in the vaccine vials. The best temperature for maintenance and transportation of MMR is 2-8°C. The time and frequency of light exposure may affect the vaccine potency. Based on the sensitivity of the vaccine strains to environmental conditions, the development of plans for storage and transportation of vaccines in different situations and training the vaccine injection staff seem necessary.