Ten Vaccine Cold Chain Monitor Cards, with instructions in English, which irreversibly change colour if exposed to temperatures above the safe limit, approved by UNICEF and the World Health Organisation for use in the Expanded Programme on Immunisation. Manufactured by Berlinger & Co, Ganterschwil, Switzerland and supplied by the UNICEF Supply Division, Copenhagen, Denmark, 1994

Vaccines need to be kept below certain temperatures to remain effective. To prevent them from spoiling when being transported over long distances and in hot climates, a ‘cold chain’ system is established. This refers to the various means by which the vaccine is kept cool – from when it leaves the laboratory to when it is needed for use. These cards are used to monitor the process and ensure that the cold chain is maintained. They irreversibly change colour if the vaccines are exposed to temperatures above the safe limit of 10ºC.

Made by Berlinger & Co. AG, these cards were was approved for use in the Expanded Programme on Immunisation (EPI) run by UNICEF (United Nations International Children’s Fund) and the WHO (World Health Organisation). When the programme was launched in 1974, fewer than five per cent of children were vaccinated. Today that figure is eighty per cent.