title: Innovations in cold chain equipment for immunization supply chains.
abstract: Since 2010, numerous new technologies have entered the immunization cold chain equipment market. The World Health Organization (WHO) Immunization Devices Programme-Performance, Quality and Safety (PQS)-has played a key role in bringing these to market. In this article, the authors explore the emergence of new cold chain equipment technologies from 2004 to 2016 and the role of PQS in this evolution.
  
  
  
  This review focuses on three major vaccine cold chain technology innovations-solar direct-drive refrigerators, long-term passive cold boxes, and equipment with user-independent freeze prevention. For the review, we used online data from WHO PQS, a literature search, and unpublished research reports.
  
  
  
  Timelines with key milestones in the emergence of the three focus technologies show delays of between one and three years between earliest field trials and publication of WHO specifications; procurement builds after the WHO prequalification of initial devices.
  
  
  
  The timelines show the role of PQS as both gatekeeper and enabler for cold chain equipment technologies. The use of target product profiles by PQS has increased its ability to signal preferred attributes and to engage with manufacturers during the product-development stage. Procurement data show how demand for solar direct-drive refrigerators increased over time. Gavi, the Vaccine Alliance, is employing demand-generation strategies to try to drive procurement of technologies with favorable technical attributes.
authors.affiliation: PATH, 2201 Westlake Avenue, Suite 200, Seattle, WA 98121, USA. Electronic address: jrobertson@path.org.
authors.forename: Joanie
authors.initials: J
authors.lastname: Robertson
authors.affiliation: Gavi, The Vaccine Alliance, Chemin des Mines 2, Geneva 1202, Switzerland. Electronic address: lfranzel@gavi.org.
authors.forename: Lauren
authors.initials: L
authors.lastname: Franzel
authors.affiliation: World Health Organization, Avenue Appia 20, Geneva 1211, Switzerland. Electronic address: maired@who.int.
authors.forename: Denis
authors.initials: D
authors.lastname: Maire
mesh_terms: D004356:Drug Storage / Q000379:methods*; D004864:Equipment and Supplies; D006801:Humans; D007114:Immunization / Q000379:methods*; D062069:Inventions; D012034:Refrigeration / Q000295:instrumentation*; D014612:Vaccines / Q000600:supply & distribution*
chemical_list: D014612:Vaccines
keywords: Cold chain equipment; Market demand; Prequalification; Specifications; Vaccine; WHO PQS