VALIDATION OF COLD CHAIN PROCEDURES SUITABLE FOR DISTRIBUTION OF VACCINES BY PUBLIC-HEALTH PROGRAMS IN THE USA

To enhance quality assurance of vaccine distribution by public health programs in the US, various methods for packing vaccines were validate d. Validation involved both tests in an environmental chamber and actu al shipping of packages by commercial overnight delivery service. Dry ice was used with vaccines needing to be kept at temperatures lower th an -14 degrees C, and water-based cold packs with other vaccines, The latter could be used in two ways. When frozen, and placed over two or three faces of well-insulated boxes, assortments of vaccines were kept cold but not frozen for 2 days or more. However packages with -15 deg rees C cold packs may reach <0 degrees C. When cold packs at refrigera tor temperature cover four to six faces of well insulated boxes, vacci ne freezing in winter conditions or warming in temperate conditions wa s slowed considerably. These approaches, which require materials costi ng less than approximate to 1% of the cost of the vaccines they protec t, provide examples of packaging suitable for overnight delivery of va ccines in the US in different seasons. Published by Elsevier Science L td.