Tag Archives: cold chain

S.K.Verma,MD1, R.Prasad,MD2
1. Professor, Department of Pulmonary Medicine
2. Prof & Head, Department of Pulmonary Medicine.

[emedpub – International Public Health : Vol 1:1] [Date of Publication: 06.30.2011]
ISSN pending

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Objectives:To determine if the results of PPD change by keeping PPD vials at room temperature (320 C-350 C) for 72-120 hours. The control comprised of PPD vials maintained in the cold chain (20C-80C).

Design of study: Prospective study from 15 July to 31 August, 2008.

Material and methods: For this study, both suspected and confirmed tuberculosis patients attending the Chest department during 15 July to 31 August, 2008 were recruited and were divided into different groups. For patients of first group (suspected tuberculosis patients), both vials of PPD were used and PPD was given in both the forearms of the same patient. Left forearm was given PPD which was refrigerated while on the right forearm, PPD kept at room temperature (320 C-350 C) for 72 – 120 hours was given. For the second group, (confirmed tuberculosis patients), patients were alternatively given PPD (one given refrigerated while the next patient was given PPD kept at room temperature).

Results: In the first group, of 80 patients, 72 (90%) had exactly identical results on both forearms. In the second group too, no difference was found with the size of PPD reaction.

Conclusions: The results suggest that one time loss of refrigeration up to 120 hours did not alter efficacy of PPD.

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Jun 30, 2011

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