POST 00480E : PROTECTION OF MORE COLD-SENSITIVE VACCINES

POST 00480E : PROTECTION OF MORE COLD-SENSITIVE VACCINES Follow-up on posts 00391E, 00400E, 00412E, 00419E, 00428E and 00475E 29 July 2002 ________________________________________________________________ Carib Nelson (mailto:[log in to unmask]) from PATH is responding to Elly (Post 00475E) and Anil Varshney (mailto:[log in to unmask]) from Health Care Consultancy Services, New Delhi, is also sharing some thoughts and suggestions. ________________________________________________________________ I don't see any problem in transporting vaccines on outreach without ice or ice packs. While it is unfortunate that VVMs are not yet on all vaccines, it seems fortuitous that OPV is the vaccine that got VVMs. Since it is the least stable vaccine, it would seem reasonable to assume that in an outreach box with a mix of vaccines, if the OVP VVM is still OK then the others vaccines should be OK as well. Uganda seems relatively cool and the OPV VVM reaches endpoint after 9 days at 25°C so a few hours or even days of no-ice outreach shouldn't be a problem, even if the vaccines have had some prior heat exposure. One finding from Indonesia, where we transported vaccines without ice, was the importance of keeping the vaccines and VVMs out of light. We found that the VVMs reach endpoint more quickly when exposed to light, even indirect light inside a building. Transporting vaccines in cold boxes or vaccine carriers, though without ice, protects them from light and helps make sure people recognize them as vaccines. The only potential problem with no-ice outreach would seem to be the practice of keeping the reconstituted measles and BCG chilled at the outreach session. Without ice this would not be possible. Is it really necessary to keep them cool after reconstitution or would a couple of hours at 25°C be OK? Carib Nelson Technical Officer Program for Appropriate Technology in Health (PATH) _______________________________________ The points raised by Elly are very important from harsh field conditions. Outreach usually would be 2- 3 hours from the static cold chain and the ice packs would melt by that time. But the temperatures in the carrier would be still below 12°C and more than adequate for vaccine preservation. Even after 8-10 hours if vaccine carriers are properly closed and not exposed to direct sunlight, vaccines would still be at favourable temperatures, within which time it is expected that immunization session would be complete. As regards steps to stop freezing, use any paper (news paper, old papers) or thick cotton and even local grass to wrap the vaccine vials after putting them in a plastic sheet, so that labels are not lost. The suggestion to use racks similar to labs is interesting but the volumes occupied by them would be 120% more than the vials volume thus straining the cold chain capacity; that means more than doubling the cold chain capacity and its consequences. Instead use a thermocool box to keep the T series and the Hep B vaccines in that box kept in the ILR. The time taken for it to reach 0° temperature would be far greater than it would be with direct exposure. Ensure that each vial is in a plastic. Dr Anil Varshney New Delhi, India ________________________________________________________ ----------------------------------------------------------------------------- CONTRIBUTIONS: Contributions to: or use your reply button! The TechNet21 e-Forum welcomes new subscribers who are involved in immunization services. SUBCRIBE: To subscribe, send an e-mail to: Leave the SUBJECT area BLANK, do not type anything. In the body text, just write: Subscribe TECHNET21E Surname Name Do not use any accents in your name and surname. UNSUBSCRIBE: To unsubscribe, send an e-mail to: Leave the SUBJECT area BLANK, do not type anything. In the body text, just write: Unsubscribe TECHNET21E ------------------------------------------------------------------------------ ARCHIVES Archives of posted messages classified by month starting with 1 January 2000 are accessible to all TechNet21 subscribers at the following site : http://listes.ulaval.ca/listserv/archives/technet21e.html Archives for postings prior to January 2000 can be found at the following site : http://www.who.int/vaccines-access/Vaccines/Vaccine_Cold_Chain/Technet Or by request to the Moderator at mailto:[log in to unmask] ------------------------------------------------------------------------------ Archives for files (documents) are under revision to clean old documents and drafts that are already replaced with new ones, and will be made available soon at a specific site. ------------------------------------------------------------------------------ The World Health Organization and UNICEF support TechNet21. The TechNet21 e-Forum is a communication/information tool for generation of ideas on how to improve immunization services. It is moderated by Claude Letarte and is hosted in cooperation with the Centre de coopération internationale en santé et développement, Québec, Canada (http://www.ccisd.org) -----------------------------------------------------------------------------