Mardi 14 Mars 2000
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Post00231 VACCINE FREEZING 14 March 2000 CONTENTS 1. CHANGING VACCINE STORAGE LOWER TEMPERATURE LIMIT FROM 0 TO 2 DEGREES? 2. VACCINE FREEZING IN TEMPERATE CLIMATES 3. DOMESTIC REFRIGERATOR MODIFICATIONS? 4. VACCINE LOSS? COST? A QUESTION 1. CHANGING VACCINE STORAGE LOWER TEMPERATURE LIMIT FROM 0 TO 2 DEGREES? Continued The current EPI vaccine storage recommendation for refrigerator storage is one month at 0 'C to +8'C. Other regions of the world and other countries recommend +2'C, or even +4'C to 8'C. Many manufacturers label their vaccine vial for storage between 0'C and 10'C. Mary Catlin, PATH, proposed in Post0218 that, considering the risk of zero degree storage on HepB - a vaccine coming into wide routine use, that we try to modify the current recommendation to +2'C to +8'C on the TECHNET Forum. The discussions so far have see to the need to raise the lower vaccine storage temperature limit for vaccines stored in refrigerators, but have identified some engineering and cost constraints. Extending the proposed change beyond electric refrigerators appears to be problematical. Other technology based solutions are not in advanced states of development. Terry Hart, IT Power India, in Post0226, pointed our that the accuracy of built in refrigerator thermometers can be in error by as much as 4 degrees, using existing technologies and called for a new specification for refrigerator thermometers. In Post0226, Michel Zaffran, WHO/V&B, raised 3 constraints that need to be evaluated if we are, in fact, going to change a vaccine storage equipment specification. ___________________________________________________________________________ From Michel Zaffran, Post0226: Constraints 1. If you restrict the allowed temperature range to 2 to 8'C, you make it more difficult for the appliance to maintain that range hence more expensive machines 2. For some of the appliances working on gas, kerosene and solar, which we use a lot, if you restrict to 2 to 8'C, then the evaporator often will not get cold enough to freeze icepacks in the freezer compartment, or you would need two compressors or cooling systems and a more expensive appliance 3. Finally, hep B does indeed freeze at-0.5 to -1 degree but a/.this is the temperature inside the vial and this corresponds to approximately -3.1 degrees in the fridge and b/ this is the scientific freezing point but there is, in fact, a substantial amount of supercooling down to -7.8 degrees before the vaccine actually crystallises and gets damaged by freezing. ___________________________________________________________________________ Todays post from Eric Laurent, WHO/WPRO, and Anthony Battersby, FBA Systems Analysts, and Mogens Munck, UNICEF, continue the discussion from TECHNET Forum Post0218 T-ZONES & LOW TEMPERATURE PROTECTION, 18 January 2000 and in Post0226 VACCINE FREEZING, on 8 February 2000. Nothing is simple. The issues that arise in this discussion are: * Should the WHO change the operational recommendation - guidance to health workers: " Adjust your refrigerator so that it operates between +2'C & +8'C under your local conditions "? * What is the status of Vaccine Vial Freeze Monitor development? * What is the status of + 2'C Eutectic Ice Pack development? * Needed: A specification for integral refrigerator temperature monitoring accuracy. * Should the WHO change the specifications for vaccine storage refrigerators or other cold chain equipment to ensure their capability of maintaining +2'C to +8'C vaccine storage at each of the Temperature Zones? [See T-Zones in Post0218] * Have the cold chain equipment manufacturers identified the cost implications of the change in specification? * If there are costs, can they be funded if needed? **** Manufacturers comments are needed, please! Contributions, comments and additions please: [[email protected]][email protected][/email] or use your reply button ___________________________________________________________________________ Date: Thu, 10 Feb 2000 22:55:45 -0500 From: Laurent Subject: Comments on Post0226 To: Technet Dear Allan, To complete the latest reply made by Michel Zaffran, about the difficulties for the appliance to maintain that range of temperature (2-8 C), we should remember that it is almost impossible to guarantee the 2'C in a well insulated cold box (at least with ice packs using only water). I did some laboratory testing for a private company which was freighting clinical products in cold boxes. We almost always got a temperature (at least for the first hours) between O and 2 C. It will be difficult to guarantee the standard +2'C to +8'C in our actual cold chain. Thanks, Eric --- Date: Wed, 9 Feb 2000 00:21:23 -0500 From: Anthony Battersby Subject: Post0226 VACCINE FREEZING To: Technet Moderator Dear Allan, I strongly support the proposition that the lower storage temperature be +2degC. With the VVMs surely we can live with +2/+10degC, still giving us an 8 degree range. There are new and very expensive vaccines which do not have adjuvant but are still damaged by temperatures below zero. As vaccine development progresses it seems that the risk of freezing temperatures becomes more critical. On which point. WE REALLY NEED A ZERO SENSITIVE VVM. Lifelines say they are working on it, when can we have an idea of when it will be available. Can anyone else make a freeze sensitive VVM? Freeze Watches are too expensive and cannot be vial specific. Anthony --- Subject: Re:Post0226 VACCINE FREEZING Author: Mogens Munck Date: 2/12/00 9:45 AM 12.2.2000 Re.: Changing vaccine storage lower temperature limit from 0 to 2 degrees. Dear Allan, Due to change of address I did not get the previous post where this topic was discussed, if I had I would have reacted sooner. However, Michel Zaffran has very much said what I wanted to say, particularly in item 1 and 2 in his contribution. Changing the limit from 0-2 degrees make things very difficult for the manufacturers, particularly if you want a fridge that at health center level keeps vaccine at positive temperatures, and AT THE SAME TIME PRODUCES ICE PACKS IN ANOTHER CHAMBER IN THE SAME FRIDGE. At health center level you need a fridge for two purposes: keeping your vaccines cold between 0/2 and 8 degrees and ice packs for outreach. The design engineers I have talked to would very much prefer a lower temperature limit of minus 2 degrees. I think that they throw the towel if you raise it to plus 2 degrees. However, WHY NOT ASK THEM FOR THEIR OPINION. Personally, I have always believed that the solution would be having icepacks with eutectics that freeze in the same temperature range at which you keep the vaccines. As soon as I receive here in Maputo my personal files from my home I will start up on field trials of Glaubers' salts, please refer to Technet Copenhagen and a previous Technet posting on eutectics. Many regards! Mogens ___________________________________________________________________________ Moderators note: Eutectics were discussed in TECHNET Post0188 COLD CHAIN & EUTECTICS & LTP, 28 September 1999. ____________________________________*______________________________________ 2. VACCINE FREEZING IN TEMPERATE CLIMATES Vaccines freeze in the cold chains in colder and non-tropical countries. The Technet has been concerned with this problem since its first global meeting in Cyprus in 1990. Work has been done to confirm the problem and develop low temperature protection (LTP) equipment specifications, the definition of a colder and temperate equipment temperature zone, and more effective vaccine management procedures. A 0'C FreezeWatch indicator is available. The soon to be prepared revision of the cold chain equipment product information sheets [PIS] should incorporate the new T-Zones and LTP. Long needed but not available are Vaccine Vial Freeze Indicators. Hala Azzam, USAID, asks what has been done and the availability of materials on vaccine freezing in temperate and colder climates. Robert Steinglass, BASICS, discusses what was done in the past under the REACH and BASICS project and identifies technet reports on the problem. Jaap Dominicus, MSF/A, is interested in research if needed. Two TECHNET reports and a presentation are now available for download. The moderator was co-author. The files are now available for download: Vaccine Storage in cold 91 Kb VaccineStorageInColdClimatesTechnet98.PDF 480 Kb 317 Kb Send an email to: [[email protected]][email protected][/email] with the message: get technet Vaccine Storage in cold get technet VaccineStorageInColdClimatesTechnet98.PDF get technet Or go to the FTP website: Click on the folder "VAX-Freeze" and then click on the files * How do we get timely implementation? Action, comments and additions please: [[email protected]][email protected][/email] or use your reply button ___________________________________________________________________________ From: "Hala Azzam" Date: 02/24/2000 1:27 PM: To: "Emily Wainwright" In response to your query about the cold climate cold chain problem in our region, I raised the question of vaccine freezing in the WHO/TECHNET meeting at Harare. I got information that PAHO had worked on a low tech solution and that for a $1000 dollar or so, a study could be performed for our region. The basic idea is to use the cold box with the ice packs at room temp and using them to maintain safe vaccine temperature during transport. As a result of raising this issue MSF has expressed interest and I recently got an e-mail from Jaap Dominicus at MSF/amsterdam saying that he is willing to do research in that area and testing of equipment in cold countries if need be. I would like to know what are the next steps we could take in this area to help facilitate this activity and use it for our region. I have enclosed below a paragraph of info from TECHNET on the problem of vaccine freezing ___________________________________________________________________________ Post0226 VACCINE FREEZING 8 February 2000 INTRODUCTION OF FREEZE SENSITIVE VACCINES INTO THE EXISTING COLD CHAIN Soren Spanner, WHO/SEARO, raises the fact that existing cold chain equipment meeting the agreed WHO/UNICEF/EPI cold chain specifications does not provide low temperature protection. This current equipment will continue to freeze damage both of the routine vaccines DTP and TT, but with the wider introduction of Hepatitis-B and Hib, among other new vaccines, this equipment will freeze large quantities of the newer more expensive vaccines. The cost to national immunization programs in wasted activity,resources, disease and credibility will not be negligible. ___________________________________________________________________________ Sincerely, Hala ---- From: "Emily Wainwright" 02/28 9:17 AM >>> Hi Robert, Didn't BASICS look into some of the issues of vaccine freezing in the NIS? What was the verdict on this type of technology in the region? Emily Wainwright Office of Health and Nutrition U.S. AID Phone: (202) 712-4569 Fax: (202) 216-3702 e-mail: [[email protected]][email protected][/email] --- From: "Robert Steinglass" , on 02/28/2000 4:30 PM: To: Emily [[email protected]][email protected][/email]@AIDW Cc: technet moderator At REACH and then BASICS, we documented the extent of the problem of accidental freezing in health facilities in Moldova and Kazakhstan using TTMs (Tiny Tim Monitors) - tiny computerized temperature data loggers. It was largely the result of our work that we supported the renewed TECHNET concern for accidental vaccine freezing in temperate climates. Remember that the global cold chain was largely designed with tropical climes in mind. Also, in the NIS, frequently health facilities conserve energy by turning off refrigerators during the winter, which doesn't help keep the temperatures inside refrigerators in the right narrow range or protect vaccines from freezing given the ambient temperatures in winter in the NIS. One of the most important problems in the NIS is that those countries still dependent on supplies from Russian suppliers (which includes most NIS for booster doses of some vaccines which UNICEF won't supply, as well as some vaccines like monovalent mumps) receive their vaccines in uninsulated wooden cartons without ice. This is the same problem we documented in 1992. I still have an example of the container. Of course, for a cold chain problem to occur at such high levels of the cold chain through which all vials must pass is ridiculous, as it is easily remedied and affects every vial. In my mind, this is one area where a bit of interest and effort is needed. A firm in Russia even has developed the right cold box, but the countries have to agree to specify its use when vaccines arrive from Russia. There are many issues. I am not sure how much more testing is really needed. It is solutions that we want. Maybe Hala would be interested in some of our materials. (You could forward this to her if you like, as I don't have her e-mail address.) Robert --- Date: Tue, 8 Feb 2000 10:02:25 +0000 From: [[email protected]][email protected][/email] (Jaap DOMINICUS) Subject: vaccine freezing To: [[email protected]][email protected][/email] Dear Alan, Anthony, Hala and others, I am well aware of the risks of freezing vaccines in warm countries. Unfortunately I have no data on the occurrence and impact of this problem in our projects. We do see the need for a freeze vial monitor. On top of this problem, we are working in cold countries, where even the transport of vaccines in cold boxes might cause freezing. Has anyone good information or recommendations on this subject? We are willing do research or testing of equipment in cold countries if need be. Best regards, Jaap Dominicus/Menno Goedhart Field Support Unit MSF-Holland --- To: From: "Hala Azzam" Subject: re: fwd: Re: fwd: Low tech solutions for vaccine freezing! Hi Robert Thanks for the info. I would like to get the documents you mention. Especially as it regards Russia and vaccine distribution, it seems leverage is needed. With GAVI/ GFCV and introduction of hepatitis B, this may be an area they may want to put pressure on. Hala Azzam, PhD AAAS Fellow USAID/E&E/EEUD/HRHA tel 202- 712 1585 fax 202- 216 3409 email: [[email protected]][email protected][/email] ____________________________________*______________________________________ 3. DOMESTIC REFRIGERATOR MODIFICATIONS? In Post0212, VACCINES & COLD CHAIN, 26 November 1999, TECHNET Forum posted: a warning from Anthony Battersby, FBA Health System Analysts, on the vaccine freezing conditions in "frost free" and "multi-flow" refrigerators and called for accelerated efforts to develop and implement vaccine vial freeze indicators. In Post0214, VACCINE FREEZING 07 January 2000, Nan Miller, CDC-THS, posted comments in responses to the ALERT: FROST-FREE REFRIGERATORS IN THE COLD CHAIN. It turned out that the refrigerators were not "multiflow" " Although freezing of vaccines remains a concern we have reduced losses due to freezing from over 47% to less than 5% during storage using only modified, frost free refrigerators. " This brought a series of questions from TECHNET Forum subscribers asking about the modifications. Terry Hart, IT Power India, informed us in Post0226, that training materials for making the refrigerator modifications on scale were validated some years ago. * In todays post Carib Nelson, PATH, asks about the modifications. Eric Laurent, WHO/WPRO, has kindly made the file of the Refrigerator Modification Manual available to the TECHNET Forum. Thanks! The table of contents and the first page are reproduced below. The file, in MSword format is available as zip file: 204 kb To get the file send an email to: [[email protected]][email protected][/email] with the message: get technet Or go to the website: Click on the folder "ColdChain" and then click on the file: Contributions, comments and additions please: [[email protected]][email protected][/email] or use your reply button ___________________________________________________________________________ From: "Nelson, Carib" To: Technet Moderator Subject: RE: Post0214 VACCINE FREEZING Date: Tue, 8 Feb 2000 03:15:00 -0800 Hi Allan: Did Nan ever respond regarding the modifications they made to the frost free refrigerators in Australia? It would be useful info for some of units we have in Indonesia. Thanks Carib --- Date: Thu, 10 Feb 2000 22:55:45 -0500 From: Laurent Subject: Comments on Post0226 To: Technet Dear Allan, Just to let you know that WPRO made some research, trial and guidelines a few years ago regarding domestic refrigerator modifications. These modifications are simple, and were aimed to be easily made by a local technician. Although such modifications can not rise the quality of a domestic refrigerator to the standard of refrigerator like Vestfrost or Electrolux, they improved the performances. In countries where domestic refrigerators are widely spread (China, the Philippines, and etc.), it could be useful. We finalized a manual with spreadsheets and drawings and will email it to the Technet Forum. Eric Laurent Thanks, Eric ___________________________________________________________________________ A DOMESTIC REFRIGERATOR FOR SAFER VACCINE STORAGE A MANUAL FOR HEALTH STAFF AND COLD CHAIN TECHNICIANS September 1996 Alasdair Wylie, WHO Consultant Eric Laurent, WHO Consultant Bernardo Bersola, Cold Chain Engineer, DoH Philippines Rene Barlin, Cold Chain Technician, DoH Philippines Roland Garcia, Cold Chain Technician, DoH Philippines ___________________________________________________________________________ CONTENTS INTRODUCTION Page Why modify ? The Objectives 2 What to modify ? The Tasks 3 How to plan the work 3 How to use this manual 3 MODIFICATIONS 1. Preparing the refrigerator 4 2. Water containers underneath the freezer 5 3. Water containers in the bottom section 6 4. Insulation material inside the door(s) 7 5. Insulated box for vaccine storage (optional) 8 6. Restarting and using the modified refrigerator 9 ANNEXES / REMOVABLE PLATES Summary of modifications 10 Materials, tools and spare parts required 11 Correct vaccine lay out in a single door refrigerator 12 Correct vaccine lay out in a double doors refrigerator 13 ___________________________________________________________________________ INTRODUCTION Why modify ? The Objectives Laboratory and field tests done for WHO show that domestic refrigerators can be unsafe for vaccine storage in tropical climates but also in cool climates : * Temperatures are often too high for vaccine storage in many parts of the refrigerator, specially close to the door and in the bottom section * During power failures, the "holdover time" - time for which the refrigerator can keep a safe temperature for vaccines - is very short, mostly because of poor insulation * When ice packs are being frozen, the temperature inside the refrigerator, specially on the top, can be negative and put adsorbed vaccines at risk (DPT, TT and Hepatitis B) Tests also show that with certain simple modifications, risks can be reduced and vaccines stored safely in a domestic refrigerator : * Temperature stability improves in the different sections of the domestic refrigerator * Holdover time increases and becomes reliable * Running costs are being reduced due to a better insulation It is essential, however, to stress that such modifications are not a substitute for proper regular use and care of the refrigerator (temperature monitoring, defrosting, door seal checking and preventive maintenance). _________________________________*_________________________________________ 4. VACCINE LOSS? COST? A QUESTION Carl Erickson, Solar Ice Company, asks an interesting question. Action, comments and additions please: [[email protected]][email protected][/email] or use your reply button ___________________________________________________________________________ From: [[email protected]][email protected][/email] Date: Tue, 7 Mar 2000 11:40:13 EST Subject: Technet Post To: [[email protected]][email protected][/email] Dear Technet Members: I am interested in information on what percentage of vaccines is lost due to overheating, freezing or mishandling and what the cost is. Carl Erickson ____________________________________*______________________________________
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