Discussions marquées : CTC

Launched today: Special Edition of Vaccine “Building Next Generation Immunization Supply Chains"

Heidi Lasher Publié dans :
PATH is pleased to present “Building Next Generation Immunization Supply Chains” a special edition of Vaccine journal which brings together evidence from global experts in 31 articles representing decades of work by country governments, implementing partners, and donors to improve immunization supply chains (iSC). The articles address the impact of iSC on vaccine coverage, current challenges, and successful pilots, promising ideas and innovations, and upstream solutions that can all help mitigate these challenges. Guest editors of the journal include Benjamin Schreiber (UNICEF), Bruce Lee (Johns Hopkins Bloomberg School of Public Health), and Raja Rao (Bill & Melinda Gates Foundation). Compiled in this way for the first time, the evidence presented in the special edition will serve as a ready reference for supply chain practitioners, underscore the importance of iSC performance for all partners in vaccine discovery and delivery, and help elevate performance improvements onto the priority agendas of global, regional, and country level stakeholders. To support the special edition and to tell the story of how strong immunization supply chains help vaccinate more kids and save more lives, PATH developed an accompanying digital feature: Connecting the Dots: How to get vaccines to more kids. The feature is designed with animated illustrations and social media friendly content to help build awareness for this important aspect of immunization programs. We invite you to check it out and share it with your networks using the social media toolkit below. What can you do? Learn More · Visit Connecting the Dots: How to get vaccines to more kids · Read Building Next Generation Immunization Supply Chains Share with your networks · Easy retweet: https://twitter.com/PATHtweets/status/847508916422496256 · Share on Facebook: https://www.facebook.com/PATHglobalhealth/posts/10154185969685059 · Social Media Toolkit: http://pathisc.nptoolkit.org/

IPAC position statement on the Controlled Temperature Chain (CTC) and the use of vaccines Out of Cold Chain (OCC)

Dörte Petit Publié dans :
Dear all, I would like to share with you a position statement from the Immunization Practices Advisory Committee (IPAC) on the Controlled Temperature Chain (CTC) and the use of vaccines out of cold chain (OCC). This statement has been prepared by the CTC working group, which has been established under the authority of IPAC in July 2016.The mission of this working group is to convene key stakeholders to define a shared vision and strategy for CTC. Members of the group include subject matter experts from IPAC member institutions or from their affiliates (WHO, UNICEF, Gavi, IFPMA, DCVMN, MSF, PATH). Regards Dörte

A Supply Chain for outreach immunization?

Immunization outreach services depend on a protective, affordable and efficient supply chain to benefit rather than obstruct outreach operations. Four potential cold-chain solutions are on offer but each has barriers to be negotiated or removed. The options are: Frozen water packs BUT we should switch to freeze-free vaccine carriers to avoid the risk of freezing: Vaccines certified for use in a ‘Controlled Temperature Chain’: PCM-filled packs used in all existing carriers and boxes prevent freezing BUT pending resolution of cost and other issues by WHO. So, which of the 3 solutions interests you most? Do you know of others? I await your views and look forward to a lively discussion! (See the attachment!)

ECTC, CTC & VVM

Hi all, I am quite new to the CTC adventure. After reading the second draft of the WHO CTC guideline, now ECTC (I also wen through the first version and the discussion in Langen and Ottawa), several questions came to my mind, and I would be extremely grateful if some of the forum members can help me out with them 1- Now that the rigid time& temperature conditions of the CTC are only one of the extended temperature conditions eligible for re-labelling, can we assume that the stability studies conducted by the manufacturers when deciding the most appropriate VVM type to reflect their product decay (at 5, 25 and 37°C), can be used for a re-labeling purpose with 37°C as a max. threshold temperature? 2- For those of you who followed the CTC initiative from the beginning, what was the scientific ground to choose 40°C as a threshold, rather than 42, 45 or 37 for that matter? In many countries where MSF intervenes & where a CTC approach can have a great impact, ambient temperatures exceed 40°C during the hot season and can be below 37°C during the cold season. Thank you beforehand for your answers and thoughts. Alain ALSALHANI Pharmacist, MSF

New! 3-part film on the Controlled Temperature Chain (CTC)

I’m delighted to announce the online release of WHO’s new 3-part film on the Controlled Temperature Chain (CTC) produced by IVB/EPI in both English and French. This 3-episode film on CTC serves as an advocacy tool in order to promote the approach among varied stakeholders. The first episode explains what CTC is, why it is useful and how it is feasible. The second episode features a case study of CTC implementation during a vaccination campaign in Côte d’Ivoire, providing insight on the health workers’ perspective. The third episode gives an outlook on the options for countries and what manufacturers can do to support countries. ENGLISH - https://www.youtube.com/playlist?list=PL9S6xGsoqIBWYg1540xBQ3XFvzz2JRrPT FRANCAIS - https://www.youtube.com/playlist?list=PL9S6xGsoqIBWRZ_KlJpNVz-ixUKo9CsT1

Buffered Temperature Chain

How about a Buffered Temperature Chain (BTC)? Vaccines which are highly thermally stable can be distributed in the Controlled Temperature Chain (CTC). To be incorporated into the CTC the vaccines must be stable enough to be stored for 3 days at 40 deg C. There are very few vaccines which are this stable. If vaccines can be incorporated into the CTC there are numerous logistical and financial advantages. Since the infrastructure is much simpler and less expensive. Establishing a “Buffered Temperature Chain”, BTC could have many of the advantages of a CTC. The BTC would keep temperatures below 28 deg C. Simple low cost methods could be incorporated to keep vaccines below 28 deg C. The expected life of vaccines of varied temperature sensitivity is given in the table below. Category No. days to end point at 28 deg C VVM 30 (High stability) 100 days VVM 14 (Medium stability) 50 days VVM 7 (Moderate stability) 25 days VVM 2 (Least stable) 7 days This data was derived from the Arrhenius graph showing Temperature Dependence. The graphs were obtained from “Temp Time” a VVM manufacture. An Mean Kinetic Temperature (MKT) temperature of 28 deg C was choosen because it could be obtained passively by combining evaporative cooling, insulation and thermal mass in simple low cost coolers. The VVM graphs are based on MKT temperature. The effect of temperature excursions could easily be monitored by a resettable direct reading MKT thermometer. Using a direct reading MKT thermometer simplifies data analysis. See Tech Net Post (http://technet-21.org/en/forums/vvm-mkt-equivalent-and-complementary-concepts/likes). Data is much easier to analyze when using a MKT thermometer rather than a data logger; the effect of temperature excursions can be seen from a single number. The color change on a VVM is based on MKT temperature. The MKT thermometer could also indicate if temperatures strayed over 40 deg C which may be harmful to the vaccines even if the MKT temperature remains below 28 deg C. If there is interest in the Buffered Temperature Chain, Sun Frost could provide direct reading MKT thermometers and temperature buffered storage containers. The containers could be built for portability or for use in a clinic. Larry Schlussler, Ph.D.
Sun Frost

New CTC infographic available

A new infographic that explains "What is a controlled temperature chain (CTC)?" is available on the WHO website: http://www.who.int/immunization/programmes_systems/supply_chain/resources/WHO_CTC_Infographic.pdf

Everything you wanted to know about CTC but were afraid to ask…

In recognition that an increasing number of vaccines are able to tolerate temperatures well above those officially stated on their labels, the World Health Organization (WHO) has been supporting efforts to assess and take advantage of the true heat stability of vaccines. Upstream work in this regard includes dialogue with vaccine manufacturers to ensure that new vaccines, where possible, reflect a maximum heat stability compatible with WHO’s definition of a Controlled Temperature Chain (CTC) and that existing vaccines are assessed to generate a clearer picture of their actual heat stability and the potential for re-licensure and pre-qualification for use in a CTC. WHO’s Programmatic Suitability for Prequalification (PSPQ) document and the Vaccine Presentation and Packaging Advisory Group’s (VPPAG) Generic Preferred Product Profile for vaccines have both been recently updated accordingly, presently containing strong recommendations for vaccines to be tested and licensed per CTC conditions, where feasible. In parallel, WHO is also conducting significant work to facilitate regulatory pathways, including the development of guidelines for the licensure of products for use in a CTC (expected in 2015). Downstream work on CTC involves supporting country uptake (see Guidelines on the Use of MenAfriVac in a CTC during campaigns) and documenting best-practices, while also generating additional data on the risks and benefits associated with CTC implementation. Three publications documenting field experience and the benefits of CTC are: (1) Simona Zipursky et al. Benefits of using vaccines out of the cold chain: Delivering Meningitis A vaccine in a controlled temperature chain during the mass immunization campaign in Benin (2) Patrick Lydon et al. Economic benefits of keeping vaccines at ambient temperature during mass vaccination: the case of meningitis A vaccine in Chad (3) Aitana Juan-Giner et al. A cluster randomized non-inferiority field trial on the immunogenicity and safety of tetanus toxoid vaccine kept in controlled temperature chain compared to cold chain WHO defines a[color=#00bbbb] Controlled Temperature Chain (CTC)[/color] as a set of conditions under which a vaccine (preferably single-antigen) with the relevant licensure and labelling may be kept and administered at ambient temperatures of up to 40°C for a limited period of time, as appropriate to the stability of the antigen and per the instructions specified on the product label. Among the conditions enabling a CTC are: [list] – A campaign or special strategy context (CTC is not currently recommended for routine immunization) where ambient temperatures do not typically exceed 40°C; – A single “temperature excursion” for a limited period of time (length of time will vary by antigen and setting, though a minimum of 3 days is preferred by WHO) immediately preceding administration; – The use of dedicated equipment and procedures to control and monitor storage temperature, including a VVM and a peak threshold temperature indicator; and – Proper use of the traditional +2 to +8°C cold chain up until the CTC excursion. WHO recommends that a CTC only be adopted when there are sufficient resources and time available for proper planning, training, supervision and monitoring. CTC should only be considered for districts demonstrating a pronounced need for the flexibility offered by this innovation. Examples of the latter would include clear cold chain constraints and challenging outreach conditions. While the benefits of dropping the cold chain may seem apparent, a CTC approach nevertheless involves some trade-offs, as listed below. [color=#008888]GAINS/BENEFITS vs COSTS/RISKS: [/color] (1) INFRASTRUCTURE / PLANNING + Starting from the location in the supply chain where the CTC starts, there is no need to provide additional space in the cold chain for the vaccine. + No additional freezer capacity is needed for ice packs. - As CTC is a new practice, there is an increased risk of confusion, especially with subsequent campaigns involving non-CTC eligible vaccines. - One peak threshold indicator per vaccine carrier or equivalent will be necessary. These are a low-cost paper card with a temperature-sensitive sticker costing under US$ 1 each, depending on the quantities needed. (2) WASTAGE + Unopened vaccines are frequently discarded when the label becomes detached or unreadable after a day in a humid vaccine carrier. A CTC eliminates this problem because the air inside the vaccine carrier will be dry. - Higher levels of closed-vaccine wastage may be seen in a CTC context if the vaccine needs to be discarded because the temperature has exceeded 40°C, or the 4-day time limit has been passed. (3) OPERATIONAL + Savings of staff time —specifically around planning and managing extra cold-chain issues and ice-pack logistics. The time used for planning cold-chain space, freezing ice packs and managing the cold-chain equipment needed for transportation can be reallocated to other supervisory and field activities. + Increased ease of vaccine transportation and reduced volume and weight burden for health-care workers to transport. + Reduced number of trips by health workers to the district level to pick up vaccines and/or ice packs - Additional time and resources may be required to familiarize vaccinators and supervisors with this new approach. The value of identifying more vaccines that are compatible with a CTC and seeking their licensure and WHO pre-qualification has been endorsed by major global health stakeholders and is part of the Global Vaccine Action Plan’s (GVAP) framework for 2011 – 2020. Currently there are almost a dozen vaccines from eight manufacturers being examined for CTC approval. We are expecting that this number will continue to increase in the near future.

CTC used in Mauritania

Last week marked the second occasion that a Controlled Temperature Chain (CTC) has been officially used with a vaccine licensed, pre-qualified, and labelled accordingly. Mauritania has just completed a Meningitis A immunization campaign (scheduled from October 14th to the 23rd) using the Meningococcal A conjugate vaccine, MenAfrivac. Two districts with particularly pronounced cold chain constraints were selected as appropriate candidates for a CTC approach: Rosso and Maghta Lahjar. Following dedicated training and microplanning, health care workers in these two districts were permitted to take the vaccine out of refrigeration up to four days prior to its use, significantly reducing the burdens they typically face to maintain the +2 to +8°C traditional cold chain. As per WHO guidelines and the vaccine’s labelling, MenAfriVac can tolerate temperatures of up to 40°C for a single cold chain excursion just prior to administration and not exceeding four days. Conducting a Meningitis A immunization campaign using the meningococcal A conjugate vaccine, MenAfriVac, in a controlled temperature chain (CTC). Mauritania, October 2014. Photos: WHO To date, Benin has been the only country to pilot the CTC approach, as it is defined by WHO, taking advantage of this cold chain policy variation during a Meningitis A campaign in December 2012. In addition to Mauritania, two more countries will be implementing a CTC approach with MenAfriVac before the end of 2014: Togo in November and Côte D’Ivoire in December. These additional experiences will provide a valuable opportunity to collect more data on CTC, as well as document best practices and draw out key lessons to apply to future efforts.

Immunogenicity and safety of tetanus toxoid vaccine in Controlled Temperature Chain

The results of a study conducted by Epicentre /Médecins Sans Frontières (MSF) assessing the immunogenicity and safety of a tetanus toxoid vaccine have been recently published in Vaccine.[sup]1 [/sup] The study was conducted in collaboration with the Project Optimize, the Belgian Institute of Public Health (WIV-ISP) and the Ministry of Health of Chad. A cluster randomized, non-inferiority trial was conducted in Moïssala district, Chad, between December 2012 and March 2013. Prior to the study, stability indicator parameters of TT kept in CTC were shown to meet international requirements after exposure of vaccines in the study area to temperatures between 24.6 and 40.1°C (mean 31.2C°) for 30 days. Women aged 14-49 years, eligible for TT vaccination and with a history of ≤1 TT dose were allocated to CTC or standard cold chain (SCC). Participants received two TT doses 4 weeks apart. Tetanus antibody titers were measured using standard ELISA at inclusion and 4 weeks post-TT2. Primary outcome measures were post-vaccination seroconversion and fold-increase in geometric mean concentrations (GMC). A total of 2,128 women (CTC=1,068; SCC=1,060) participated in the study. Seroconversion was reached by >95% of participants in the CTC and cold chain groups; upper 95%CI of the difference was 5.6%. Increases in GMC were over 4-fold; upper 95%CI of GMC ratio was 1.36 in the adjusted analysis. Few adverse events were recorded. This study demonstrates that TT can be used in CTC without a significant loss of vaccine effectiveness. The use of TT in CTC could facilitate the implementation of Supplementary Immunization Activities (SIAs) targeting high-risk populations living in remote and hard to reach areas. [sup] 1[/sup] In press: Juan-Giner A, et al. A cluster randomized non-inferiority trial on the immunogenicity and safety of tetanus toxoid vaccine kept in controlled temperature chain compared to cold chain. Vaccine (2014), http://dx.doi.org/10.1016/j.vaccine.2014.09.027

Call for less heat-sensitive vaccines

A couple of months ago, Médecins Sans Frontières (MSF) produced a package of materials in support of their call for wider use of existing vaccines in the “controlled temperature chain” or CTC. An issue brief, Vaccinating Children Beyond the Cold Chain, is available in English and French. It is attached to this message. The Issue Brief, as well as animation and infographics on CTC and the thermostability of vaccines, are available from http://www.msfaccess.org/bestshot Enjoy the reading ! Julien
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World Immunization Week: MSF calling for heat-stable vaccines to help reach the one in five children

This note has been cross-posted from the GAVI CSO forum with many thanks! Dear colleagues, This week on occasion of the World Immunization Week, Médecins Sans Frontières/Doctors Without Borders (MSF) has released a call for greater attention to the need for heat-stable vaccines to facilitate access to life saving vaccinations to the one in five children currently left out of global immunization efforts. You can find more information on the call for heat-stable vaccines below, including information that explains the challenges that medical organisations like MSF and governments face in reaching all children in need. The requirement for vaccines to be kept constantly cold is proving a barrier in improving immunization coverage rates. We are asking pharmaceutical companies, governments and philanthropic R&D funders to urgently take steps to increase the thermostability of existing vaccines, and develop new vaccines that are easier to use - with greater tolerance for heat - to reduce the logistical hurdles imposed by the ‘cold chain.’ Currently, the requirement to keep vaccines between 2°C and 8°C is a major obstacle for MSF and other partners delivering vaccination to the children who are disproportionately affected by vaccine-preventable diseases. Cold chain challenges could be eased if pharmaceutical companies generated and released more information on the true heat sensitivity of their vaccines. For example, this week, we are releasing the results of a new MSF study that shows a tetanus vaccine remains effective for up to a month when used outside of a strict cold chain For more information, please read our new Issue Brief: Vaccinating Children beyond the 'Cold Chain', available at the link below and also available in French, attached: http://www.msfaccess.org/content/issue-brief-vaccinating-children-beyond-cold-chain Finally, we are also launching a new website where you can find information about MSF's vaccination work: http://www.msfaccess.org/bestshot Do not hesitate to contact us if you require any further information or have any questions. Thank you and kind regards, Kate Elder Vaccines Policy Advisor Médecins Sans Frontières | Access Campaign 333 7th Avenue, 2nd floor New York, NY 10001 Tel: +1 212 763 5737 Cell: +1 917 213 5365 kate.elder@msf.org http://www.msfaccess.org/about-us/media-room/press-releases/heat-stable-vaccines-urgently-needed-reach-one-five-children#overlay-context=
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Use of MenAfriVac™ (meningitis A vaccine) in a controlled temperature chain (CTC) during campaigns

The need to keep vaccines in a 2°C to 8°C cold chain is a constraining factor for many immunization campaigns due to limited storage capacity and/or limited ice pack freezing capacity; supplementary immunization activities planned across sub-Saharan Africa to introduce MenAfriVac™ are a good example. In 2012, the licence for the Serum Institute of India’s meningitis A vaccine, MenAfriVac®, was changed based on a thorough review of scientific data by regulatory authorities and the World Health Organization (WHO) to allow for the use of the vaccine for a period of up to 4 days at temperatures of up to 40°C in a controlled temperature chain (CTC). WHO has published three documents to provide support on use and adoption of CTC: 1. This document gives guidance on how to use the CTC: Use of MenAfriVac (meningitis A vaccine) in a controlled temperature chain (CTC) during campaigns Use of MenAfriVac (meningitis A vaccine) in a controlled temperature chain (CTC) during campaigns 2. A training module that teaches how to integrate the CTC into your routine immunization programme: Training module for organizing immunization sessions 3. This document tells countries how to adapt the generic training module to the local situation: Adaptation guide and facilitator's guide

In Pictures: Delivering MenAfriVac using the CTC approach

by Dan Brigden, PATH In November 2012, the first immunization campaign to use a controlled temperature chain (CTC) took place in Banikoara in northern Benin. This photo set contains photographs taken during the campaign, where over 155,000 people were vaccinated using the CTC approach. Access the photo slideshow directly. You can click “Show info” in the top right corner to view/hide photograph descriptions, and click the following button in the bottom right corner to view the slideshow in full-screen mode. The photo set accompanies an article on the MenAfriVac CTC campaign in the February 2013 edition of Op.ti.mize, an electronic newsletter on the vaccine supply chain. You can view an archive of all Op.ti.mize newsletters here: http://www.path.org/projects/project-optimize-newsletter .

Notes from the field: Delivering MenAfriVac using the CTC approach

by Simona Zipursky, PATH; Mamoudou Harouna Djingarey, WHO/AFRO; Olivier Ronveaux, WHO/AFRO; Sylvestre Tiendrebeogo, Consultant In November 2012, the first immunization campaign to use a controlled temperature chain (CTC) took place in Banikoara in northern Benin. MenAfriVac is a meningitis A vaccine developed by the Serum Institute of India with support from PATH and the World Health Organization (WHO) through the Meningitis Vaccine Project. It is the first vaccine to be licensed by regulatory authorities and authorized by WHO for use at ambient temperatures of up to 40°C for up to four days. The campaign in Banikoara provided us with a unique opportunity to get a better understanding of how the CTC approach works in the field. The Beninese Ministry of Health was able to more clearly assess opportunities and challenges with the approach and WHO was able to identify ways to improve guidance and training materials developed through the Immunization Practices Advisory Committee. Everyone involved was able to see how the CTC works in field conditions and what adjustments to campaign procedures need to be made before the approach can be applied in other settings. Overall, the effort was a resounding success. Although the results from the monitoring study are still being analyzed, no serious adverse events following immunization were recorded during the campaign. We were also reassured that there was no increase in vaccine wastage. With MenAfriVac only prequalified for use at ambient temperatures up to 40°C, we had feared that using the CTC approach in Benin’s often searing midday heat might lead to unacceptably high levels of vaccine wastage. But over the course of the campaign, closed vial wastage (the number of vaccine vials thrown away without being opened) accounted for just 10 out of 15,500 vials, and some of those were due to vial breakage. We found that simple solutions proved extremely effective. Our system to keep track of how long vials had been out of the cold chain for is a good example. At the end of each day, any unused vials that had been kept in a CTC for a day were marked with a single line. At the beginning of the following day, these marked vials were used first. If by chance these marked vials were not used again, at the end of each subsequent day, they were marked with an additional line (up to three). This system was easy for health care workers and supervisors to implement and ensured that prequalification conditions were met. Another challenge was how to know if the 40°C temperature threshold had been exceeded. The ambient temperature reached 39°C on many days, and we were worried that vaccines would be exposed to even higher temperatures during transportation or by direct exposure to the sun. To ensure this did not happen, we used a peak threshold indicator—a simple laminated card with a temperature-sensitive sticker that changes color when the threshold (in this case 40°C) is reached. One indicator was placed in each vaccine carrier. Vaccinators were instructed to check the indicator each time they took a vial out of the vaccine carrier and contact their supervisor if they noticed the sticker had changed color. In this way, vials found to have been exposed to temperatures above 40°C would be discarded. After extensive use, the indicators were deemed easy to read and use by health care workers, and supervisors’ reports validated their correct use in the field. Together with the vaccine vial monitors (VVMs) on the vaccine’s label, which monitor a vaccine’s cumulative exposure to heat, the peak threshold indicator gave health care workers confidence that the vaccines kept in a CTC were still safe and effective to use. [size=10]A peak threshold indicator placed in a vaccine carrier. Photo: WHO/Olivier Ronveaux[/size] Aside from these few simple modifications, the pilot in Banikoara used existing equipment, including the standard grey vaccine carriers employed in other campaigns. This allowed us to protect vaccines from high temperatures and direct sunlight. Just as importantly, we found that these “grey boxes” were so well known within the community as symbols of immunization that replacing them with something else would have been a social mobilization challenge. While many anticipated challenges were ultimately easy to address, new challenges emerged. The peak threshold indicator, designed to irreversibly change color when the threshold was reached, turned out to be very sensitive when exposed to direct sunlight. Even with an ambient temperature of just 28°C, if the indicator was placed in in the path of the sun, it quickly changed color. As a result, we adjusted our guidance to health care workers, suggesting they read the indicator in the vaccine carrier rather than removing it from the vaccine carrier and placing it on a table to read. With this additional guidance, the problem was solved. Concern that health care workers would be confused by having more than one set of rules to follow on immunization campaigns proved unfounded. It had been feared that using the CTC approach for one campaign and then returning to the regular cold chain for another might lead to inappropriate cold chain procedures being followed. But in the polio vaccination campaign conducted in Banikoara just a week after the MenAfriVac campaign, the cold chain was again used properly. At the end of the MenAfriVac CTC campaign, vaccinators and supervisors were asked what they thought of the approach. After weighing the benefits, the challenges, the learning curve, and the limitations, every person asked said they preferred conducting campaigns “the CTC way.” Such high acceptance in Benin was not necessarily expected, as the cold chain functions relatively well and the roads are generally manageable. There is much work to do before the CTC can be applied elsewhere. Not just in putting what we learned from Benin into action, but also in taking what we heard from Benin—the need for more vaccines to be licensed for CTC, the call for more flexibility—and work with manufacturers and regulators to make that happen. The work is moving forward, and the results from Benin suggest a positive future for CTC. This article is accompanied by a slideshow of photographs taken during the MenAfriVac CTC campaign in Banikoara. You can view the photo set on Flickr.

Stable vaccines at tropical temperatures

http://www.timesche nnai.com/ index.php? mod=article&cat=General&article=47839 Now vaccines can be stored at room temperature 02.18.2010 (GMT+5.5) London: For the first time scientists at Oxford University have found a way of keeping vaccines stable without refrigeration, even at tropical temperatures.The technology has the potential to revolutionise vaccination efforts, particularly in the developing world where infectious diseases kill millions of people every year, by removing the need for fridges, freezers and associated health infrastructure.The work published in the journal Science Translational Medicine involved collaboration between the university scientists and a company, Nova Bio-Pharma Technologies.Scientists carried out the proof-of-concept study, showing that vaccines they are developing could be stabilised for months using Nova's patented technology, called the Hypodermic Rehydration Injection System (HydRIS)."Currently vaccines need to be stored in a fridge or freezer," explains lead author Dr Matt Cottingham of the Jenner Institute at the University of Oxford."That means you need a clinic with a nurse, a fridge and an electricity supply, and refrigeration lorries for distribution" .He added: "If you could ship vaccines at normal temperatures, you would greatly reduce cost and hugely improve access to vaccines. You could even picture someone with a backpack taking vaccine doses on a bike into remote villages.”The team demonstrated it was possible to store two different virus-based vaccines on sugar-stabilized membranes for 46 months at 45 degree Celsius without any degradation.The vaccines could be kept for a year and more at 37 degree Celcius with only tiny losses in the amount of viral vaccine re-obtained from the membrane."We've shown that a very simple way of heat-stabilizing vaccines works for two viruses that are being used as the basis for novel vaccines in development, " says principal investigator Professor Adrian Hill of Oxford University."This is so exciting scientifically because these viruses are fragile. If we are able to stabilize these, other vaccines are likely to be easier," he said.The method involves mixing the vaccine with the sugars trehalose and sucrose. The mixture is then left to slowly dry out on a simple filter or membrane.As it dries and the water evaporates the vaccine mixture turns into a syrup and then fully solidifies on the membrane. The thin sugary film that forms on the membrane preserves the active part of the vaccine in a kind of suspended animation, protected from degradation even at high temperature.Flushing the membrane with water rehydrates the vaccine from the membrane in an instant."The beauty of this approach is that a simple plastic cartridge, containing the membrane with vaccine dried on, can be placed on the end of a syringe," explains Dr Cottingham.Pushing a liquid solution from the syringe over the membrane would then release the vaccine and inject it into the patient.Professor Hill adds: "The World Health Organization’s immunization programme vaccinates nearly 80 per cent of the children born today against six killer diseases: polio, diphtheria, tuberculosis, whooping cough, measles and tetanus."One of the biggest costs is maintaining what's called the cold chain making sure vaccines are refrigerated all the way from the manufacturer to the child, whether they are in the Western world or the remotest village in Africa," he said.If most or all of the vaccines could be stabilized at high temperatures, it would not only remove cost, more children would be vaccinated, he said. Dr. Omesh Kumar BhartiM.B.B.S.,D.H. M.,M.A.E. (Epidemiology)Directorate of Health Safety and Regulation, Himachal Pradesh

Increasing the acceptable temperature range for certain vaccines

by Michel Zaffran, WHO; Julie Milstien, consultant; and Modibo Dicko, WHO It has long been known that certain vaccines are stable for long periods of time at temperatures outside the standard cold chain protocol of 2[sup]o[/sup] to 8[sup]o[/sup]C. However, until recently, there have been few reasons to consider changing the relatively simple, blanket policy that all vaccines need to be stored between 2[sup]o[/sup] and 8[sup]o[/sup]C. The only exceptions have been occasional "off-label" use of some vaccines for immunizing hard-to-reach populations, such as "out-of-cold-chain" use of hepatitis B vaccine birth dose; use of tetanus toxoid in pregnancy, just before delivery; and the use of oral polio vaccine with or without cool water packs during campaigns. A change in the vaccine storage temperature policy is not easy. It requires a great deal of evidence gathering, licensing and regulatory changes, and careful consideration of the programmatic impact of the change for countries. Depending on the country, such a change may merit new equipment, training, and monitoring to ensure that the new policy is followed correctly and consistently for all applicable vaccines. However, despite the challenges in doing so, a policy change is becoming increasingly necessary for the following reasons: Temporarily removing vaccines from the traditional cold chain is often the only way to provide on-time immunizations to those who are hardest to reach.A large amount of relatively costly vaccines are currently being exposed to freezing temperatures that can damage them. Newer vaccines are much bulkier and much more costly than traditional Expanded Programme on Immunization vaccines. Under the current policy the only way to accommodate new vaccines is to build new cold rooms, buy bigger coolers, and require health workers to carry heavier cold boxes. Because several vaccines are quite stable at temperatures above 40[sup]o[/sup]C for months at a time, refrigerating these vaccines at all times is unnecessary, potentially harmful (due to accidental freezing), and a waste of precious resources. The World Health Organization (WHO) and PATH, through project Optimize, are collaborating with manufacturers, regulatory bodies, countries, and a programmatic working group to take steps toward new policies that allow for vaccines to be handled in a “controlled temperature chain” where certain heat-stable vaccines can be stored at controlled temperatures that are outside of the traditional 2[sup]o[/sup] to 8[sup]o[/sup]C cold chain. To achieve this change, work is ongoing in three streams: 1. Define the regulatory pathway. The process begins by gathering evidence to understand precisely how higher temperatures may impact vaccine potency and delivery in real-world situations for each heat-stable vaccine. A study of this nature is currently underway with the hepatitis B vaccine. This particular vaccine was chosen for its well-known stability to heat, and for the need to reach infants as soon as possible after birth. Positive results from this study will facilitate relabeling the vaccine for its true heat-stability profile, thus giving countries the option to implement new outreach strategies by using the vaccine within a broader, yet controlled-temperature range. 2. Gather more country-level evidence. Country-level evidence can further confirm vaccine temperature stability in real-world settings, thus contributing to the evidence base upon which regulatory issues are decided. It will also generate critical data that will help inform and develop implementation strategies. 3. Provide programmatic guidance. A programmatic working group has been convened to discuss and develop programmatic guidelines for countries to follow should they consider adopting new temperature policies for specific vaccines. When the licensing, regulatory, and programmatic requirements are met, then WHO will be in a better position to consider changes to the blanket temperature storage policy to accommodate different handling requirements for heat-stable vaccines under controlled temperatures. When is a new policy likely to be developed? The hepatitis B study, which will help define the regulatory pathway for a policy change, is ongoing. Results of the laboratory testing are expected by early 2010. If the results are positive, a change in the regulatory license for relevant hepatitis B vaccines could be proposed to allow storage and transport beyond the traditional 2[sup]o[/sup] to 8[sup]o[/sup]C range. However, this is only a first step. Ideally, all vaccines would be licensed to their true stability. While some vaccines will need to remain in the 2[sup]o[/sup] to 8[sup]o[/sup]C range, others will be able to be handled in a broader controlled temperature range, giving countries increased flexibility to deal with an increasing number of vaccines.

What's in a name? Selecting a term for 'storing and transporting vaccines outside of the 2-8°C range'

Today, most vaccines are licensed for storage between 2-8°C, regardless of their true stability. While there are some vaccines that do need to be kept at this specific temperature range, studies have shown that most vaccines are able to withstand higher temperature ranges for a specific period of time and that keeping them at 2-8°C puts some of them at risk of freeze damage. This isn't to say that vaccines should not still be stored at 2-8°C, but that if the vaccine is in fact stable enough to allow, for example, storage at 25°C for 30 days, that the product's license should reflect this so that countries have the option to use it as such if they wish. Looking at alternative temperature storage for vaccines has many advantages, chief amongst them: • Taking full advantage of the real stability of vaccines to improve coverage by reaching out to remote populations beyond the reach of the current cold chain • Increasing efficiency and effectiveness of immunization services to new target groups and in campaign/pandemic situations • Protecting freeze-sensitive vaccines • Facilitating the integration of the immunization supply chain with those of other health care products There are many regulatory and programmatic challenges that will need to be addressed before storing certain vaccines outside of the 2-8oCdegrees becomes a feasible practice, however one of the first issues to tackle is what we call this new storage/transport arrangement. While many options have been proposed, we'd like to get input and opinions from as many people as possible before choosing an official term. Some suggestions thus far have included: Out of the cold chainFlexible cold chainControlled ambient temperature storageHigher temperature storage[/ol] Please help us find the best term possible! Michel Zaffran Senior Adviser & Project Optimize Director
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Oral Polio Delivered Safely Without Icepacks in Recent Study

Oral Polio Delivered Safely Without Icepacks in Recent Study by Ariane Halm, EPIET (European Programme for Intervention Epidemiology Training), and Olivier Ronveaux, WHO Optimizerecently completed a study with the World Health Organization (WHO) Country Office and the Ministry of Health in Mali to determine the feasibility of using oral polio vaccine (OPV) out of the traditional cold chain temperatures during a National Immunization Day campaign. In four health areas, thirty-nine vaccination teams successively transported OPV in the vaccine carrier with icepacks (keeping the vaccine at cold chain temperatures) and without icepacks in order to evaluate the outcome of transporting the vaccines without ensuring a continuous cold chain. The practice at ambient temperature was limited to a maximum of one outreach day. The study concluded successfully, with no major problems or deviations to the methodology. A total of 14,913 children were vaccinated in the study areas. About half of the vials (54%) were transported in vaccine carriers without icepacks, and all of these vials were still usable as indicated by the vaccine vial monitors at the time of the last administered dose despite ambient temperatures ranging from 25° to 40°C (mean of 27°C). Wastage rates were lower for the vials traveling without icepacks because they did not have the problems usually caused by melting ice and icepacks (e.g., moisture on the label making it unreadable, vials contaminated with water, etc.). Health workers also reported that the ambient temperature transport facilitated preparation and implementation activities, reduced the weight they needed to carry, and required less time (possibly resulting in more children being immunized). Direct costs for the ambient temperature transport were lower, primarily because icepacks did not need to be resupplied. The study suggests that ambient temperature transport of OPV may provide a safe alternative in geographically challenging settings or where cold chain material cannot be made available. However, vaccines transported in ambient temperature must come with vaccine vial monitors and staff must be adequately trained to interpret them. This study adds evidence to the possibility that ambient temperature supply chains may be one of the solutions to address constraints in cold chain space that are likely to occur with new vaccine introduction. A paper on this experience is being submitted for publication in a scientific journal. We invite you to comment on or post a question relating to this article by clicking the “post reply” button on this page. You will have to log in or register, but the process is very simple. To link back to the Optimize e-newsletter, click here. [img width=228]http://www.technet21beta.org/components/com_agora/converter/uploads/user_photos/dsc00735.jpg[/img] [img width=228]http://www.technet21beta.org/components/com_agora/converter/uploads/user_photos/dsc00751.jpg[/img] [img width=228]http://www.technet21beta.org/components/com_agora/converter/uploads/user_photos/dsc00675.jpg[/img] [img width=228]http://www.technet21beta.org/components/com_agora/converter/uploads/user_photos/dsc00725.jpg[/img] Photo Courtesy : Olivier Ronveaux
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POST 00724E : COOL TECHNOLOGY : THE END OF THE COLD-CHAIN?

POST 00724E : COOL TECHNOLOGY : THE END OF THE COLD-CHAIN? 8 November 2004 _____________________________________ Below is an article published in "The Economist". The delay in posting it was due to the translating into French. Do not dwell on the few simplifications or generalizations of a journalistic nature. It is the essence that counts! This article has also been added in both languages to the "General News" sub-page of our site at : http://www.technet21.org/gennews.html ____________________________________ From The Economist, Oct 21st 2004, print edition SCIENCE AND TECHNOLOGY : A trick from nature could help vaccinate millions of poor children IMMUNISATION is a pain, and not just for those lucky enough to get a shot in the arm. Vaccines themselves, which are made largely out of protein, have to be refrigerated to prevent them going off. Keeping vaccines at the right temperature on their long journey from the factory in, say, Europe to a village in sub-Saharan Africa is a costly and complex business. Experts estimate that almost half of all vaccine doses are wasted because of temperature damage, which is cold comfort to the families of the 2m children in poor countries who die every year from measles and other vaccine-preventable diseases. Cambridge Biostability, a British biotechnology firm, may have found a solution by borrowing a trick from nature. Some plants, and even insects, are able to survive hundreds of years in suspended animation through a process called anhydrobiosis. Faced with drought, their tissues produce sugars which turn into a syrup as they start to dry out, eventually forming a sort of glass which preserves them perfectly. Add water, and these organisms spring back to life. Scientists at Cambridge Biostability have adapted this technique to vaccines. First, they coat clusters of vaccine molecules with a sugar spray. Then they dry them in such a way that they form tiny glassy beads. These sugar "microspheres" are then suspended in a non-water-containing liquid, which keeps them intact until they are injected into the body. There, the sugar dissolves in the blood and the vaccine is released. The advantage of this is that the microspheres can survive temperatures as high as 55°C for months, conditions that destroy normal vaccines. Tests in mice and guinea pigs have shown that such vaccine microspheres are as safe and effective as conventional shots. The developers point to other advantages, too. Even though conventional vaccines are transported as dry powder rather than in solution, they still need to be dissolved in water before injection. That can lead to bacterial contamination or worse if the wrong sort of liquid is used. The new vaccine microspheres, on the other hand, can be injected straight into the body, eliminating those sorts of mistake and with them the need for the preservatives found in ordinary vaccines. In addition to that, because the sugar-glass coats the vaccine molecules and thus isolates them, various vaccines in their own microspheres can be mixed together in a single jab. This is something that is hard to do with conventional shots, since different vaccine molecules will react together unless insulated from one other. Cambridge Biostability, with support from Britain's Department for International Development and the Programme for Appropriate Technology in Health, an American not-for-profit group, is working on a sugar-glass version of a combined shot against five nasty childhood diseases, including diphtheria and meningitis. The next step is to test the new formulation in human volunteers, which will be done in India by the firm's commercial partner, Panacea Biotec, based in Delhi. If all goes well, the vaccine could be on the market in three years' time. By eliminating the need for refrigeration, the technology could save up to $300m a year in global vaccine costs, which means another 10m poor children could be protected. Moreover, the technique may also work with other protein-based drugs, such as insulin. Sugar-glass could one day prove one of biotech's sweetest successes. ______________________________________________________________________________ Visit the TECHNET21 Website at http://www.technet21.org You will find instructions to subscribe, a direct access to archives, links to reference documents and other features. ______________________________________________________________________________ To UNSUBSCRIBE, send a message to : mailto:LISTSERV@listes.ulaval.ca Leave the subject area BLANK In the message body, write unsubscribe TECHNET21E ______________________________________________________________________________ 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) ______________________________________________________________________________
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