Thermal Stabilization of Viral Vaccines in Low-Cost Sugar Films

Sci Rep. 2019 May 21;9(1):7631. doi: 10.1038/s41598-019-44020-w.


Most currently available vaccines, particularly live vaccines, require the cold chain, as vaccine efficacy can be significantly hampered if they are not stored in a temperature range of 2-8 °C at all times. This necessity places a tremendous financial and logistical burden on vaccination programs, particularly in the developing world. The development of thermally stable vaccines can greatly alleviate this problem and, in turn, increase vaccine accessibility worldwide. In this paper, we detail a simple and cost-effective method for stabilizing live vaccines that uses FDA-approved materials. To this end, we dried enveloped DNA (Herpes Simplex Virus type 2) and RNA (Influenza A virus) viral vaccines in a pullulan and trehalose mixture. The results of these studies showed that the live-attenuated HSV-2 vaccine retained its efficacy for at least 2 months of storage at 40 °C, while the inactivated influenza vaccine was able to retain its immunogenicity for at least 3 months of storage at 40 °C. This work presents a simple approach that allows thermo-sensitive vaccines to be converted into thermo-stable vaccines that do not require refrigeration, thus contributing to the improvement of vaccine deployment throughout the world.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chlorocebus aethiops
  • Costs and Cost Analysis
  • DNA, Viral / chemistry
  • DNA, Viral / immunology
  • Dogs
  • Herpes Simplex Virus Vaccines / chemistry*
  • Herpes Simplex Virus Vaccines / economics
  • Herpes Simplex Virus Vaccines / immunology
  • Immobilized Nucleic Acids / chemistry*
  • Immobilized Nucleic Acids / immunology
  • Immunogenicity, Vaccine
  • Influenza Vaccines / chemistry*
  • Influenza Vaccines / economics
  • Influenza Vaccines / immunology
  • Madin Darby Canine Kidney Cells
  • Membranes, Artificial*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • RNA, Viral / chemistry
  • RNA, Viral / immunology
  • Sugars / chemistry
  • Vaccine Potency*
  • Vero Cells


  • DNA, Viral
  • Herpes Simplex Virus Vaccines
  • Immobilized Nucleic Acids
  • Influenza Vaccines
  • Membranes, Artificial
  • RNA, Viral
  • Sugars

Grant support