WHO and UNICEF urge wider use of vaccine vial monitors

World Health Organization (WHO) and UNICEF have issued a new joint policy statement on the role of vaccine vial monitors (VVMs) in improving access to immunization, on the 10-year anniversary of introduction of VVMs in immunization programmes.

A VVM is a simple tool that clearly warns if a vaccine is likely to have been damaged by heat. Its use over the last 10 years has made it possible for more children in more places to have access to vaccine.

It is a circular indicator, printed directly on a vaccine vial label or affixed to the top of the vial or ampoule. The inner square of the monitor is made of heat-sensitive material that is light in colour but becomes darker when exposed to heat, indicating to health workers that the vaccine may no longer be effective.

"Handling vaccines requires great care. All vaccines are sensitive to heat and some to freezing. Vaccine vial monitors are useful tools for detection of the vaccine's exposure to excessive temperature, thus contributing to success of immunization programmes," said Daisy Mafubelu, assistant director-general of the Family and Community Health Cluster, WHO.

For example, during the May 2006 earthquake in Yogyakarta, Indonesia, much of the infrastructure was damaged including the refrigeration facilities at the health centres. Normally, unrefrigerated vaccines would need to be discarded. In this case, by observing the monitors on the vaccine vials, health workers were able to see that the vaccines were still usable. In total, up to 50 000 doses of various vaccines were saved from being wasted thanks to VVMs.

Since their introduction in 1996, nearly 2 bn monitors have been used on vaccine vials. WHO and UNICEF estimate that the use of VVMs is saving the global health community at least US$5m p.a. Over the next 10 years, the monitors will allow health workers to recognize and replace more than 230m doses of unusable vaccines.

The new WHO/UNICEF joint policy statement urges all vaccine self-procuring countries to include the vaccine vial monitors among the minimum requirements for vaccine purchase agreements. It also urges all donor agencies and international non-governmental organizations to adopt a policy that explicitly includes vaccine vial monitors as a minimum standard in every vaccine donation.

GAVI Alliance deputy executive secretary Michel Zaffran said: "Since their introduction 10 years ago, vaccine vial monitors have played a crucial role in overcoming challenges related to safe delivery of vaccines, especially in hot climates where vaccine refrigeration is weak or non-existent. GAVI has consistently supported the inclusion of VVMs with the vaccines it funds, and we urge all vaccine manufacturers to ensure all their products be delivered with vaccine vial monitor technology included. We are confident that the GAVI requirement that all new vaccines be fitted with monitors has helped move this important agenda forward."