Post00304 VACCINE FREEZING CONTINUED 13 December 2000
CONTENTS
1. Post00299 VACCINE FREEZING CONTINUED
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1. Post00299 VACCINE FREEZING CONTINUED
Our discussion of the problem of vaccine freezing, cold chain and systems
management, and mechanisms to monitor and prevent vaccine freezing,
continues with todays postings from Ann Kempe, SA/DHS, Terry Hart, ITPI, and
Hans Everts, WHO/EPI.
Ann discusses the body of knowledge and experience in this critical
logistical problem in Australia - and its parallels elsewhere.
Terry asks what happened to the development of new vaccine storage equipment
specifications based on temperature zones - including freeze protection.
These specifications were intended to guide manufacturers in the production
of cold chain equipment and to guide purchasers in their equipment
selection.
Hans points out that manufacturers are on notice to apply solutions to the
vaccine freezing problem by the end of the year 2000 and that testing
specifications have been tightened to eliminate equipment which had even
minor negative temperature periods during the test cycle.
* Revised equipment specifications and the availability of low temperature
protected vaccine storage equipment will be helpful in the long term.
The field reality is that very few programs properly monitor the occurrence
of vaccine freezing events and take little or no action to do so. The "no
news is good news" principle is hard at work.
* Improved management of the cold chain at all levels is needed. These
improvements can only come about by the implementation of better systems and
methods. This in turn can only be achieved through active, competency based
training. Budgetary or administrative constraints in many programs prevent
the wide provision of refresher training of health workers.
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From: "Kempe, Ann (DHS)"
To: "'Technet Moderator'"
Subject: RE: Post00299 VACCINE FREEZING CONTINUED
Date: Wed, 29 Nov 2000
Allan
As you know a lot of effort and research has been conducted in Australia
(South Australia and NT and other states) to demonstrate the problem around
freezing of vaccines. A Medline search will reveal the results of this
research activity. Australia has many logistical problems with cold chain
that are similar to cold chain issues faced by WHO sponsored immunisation
programs. We have to face the problem of vaccine transport over long
distances in extremes of temperatures. I recommend any Technet reader to
review to published data. At the moment one of my colleagues is undertaking
research using a mouse model, to demonstrate the effect of freezing (defined
by difference temperatures below 0 degrees), on DTP vaccine. The research
will be published in the near future.
We have demonstrated repeatedly in Australia that vaccines like DTPa, HbOC,
DT, hepB and other combination vaccines are regularly compromised by
"thermal abuse" when fridges run too cold and vaccines are packed into cold
boxes with too many cold packs and are not monitored with a freeze watch or
equivalent.
I recently did a consultancy in China with Alan Schnur for the WHO, to
review education needs for health workers in 4 provinces. In the field trip
I was concerned at the poor understanding of managing cold chain in relation
to freezing although the heat issues seemed to be addressed. The lack of
monitoring with adequate CCMs was also a concern.
regards
Ann Kempe
South Australia - Immunisation Coordinator
CDC Branch; Public Health
Department of Human Service
PO Box 6, Rundle Mall
Adelaide, SA, 5000
Australia
Phone: (08) 82267177
Fax: (08) 82267197
Email: [log in to unmask]
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From: Terry Hart
To: "'Technet Moderator'"
Subject: RE: Post00299 VACCINE FREEZING CONTINUED
Date: Sun, 3 Dec 2000
Organization: IT Power India
Hi Allan,
ITPI had started to do some work related to this in 98, which included
definition of ambient temp boundaries in different geographic zones. We
ended up after much interaction with Hans with a common
understanding/agreement of what the operating boundaries for Cold, Temperate
and Hot climate fridges should be.
The follow on action, which to my knowledge never occurred was to prepare
specs for fridges suitable for use in each zone. A price advantage was
anticipated for Temperate climate fridges where specs did not need to be so
stringent. We would be interested in continuing with this work. Since Soren
is now in Delhi it would be particularly easy and useful to work on this
jointly.
Best regards
Terry
[Terry Hart refers to Soren Spanner, WHO/SEARO. Soren has previously posted
data on vaccine freezing in a 3 year study in India as well commented to the
development of equipment specifications and testing procedures.]
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From: [log in to unmask]
Date: Wed, 29 Nov 2000 11:29:47 +0100
Subject: RE: Post00299 VACCINE FREEZING CONTINUED
To: Technet Moderator
Although I agree a lot has still to be done, I do not think we can say the
ball has not been picked up.
As I said in the previous message all manufacturers will have to show they
dealt with the freezing problem before the end of 2000 and progress was
made. In addition, whereas previously minor negative temperatures during
testing were considered as marginal failure and would not prevent an
appliances from being listed, this is not the case anymore.
It was definitely not enough, but the ball was picked up.
Hans Everts
Technical Officer
EPI
WHO Geneva
Tel: 00 41 22 791 3683
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