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• It is difficult to identify and resolve underlying cold chain equipment problems. • Monitoring CCE uptime can misrepresent the effects of temperature on vaccines. • Long power outages can have a minimal impact on remaining VVM life. • Remaining VVM life calculations can give insights to cold chain weaknesses. Vaccine Vial Monitors (VVM) are used to estimate if a vaccine has been exposed to excessive hot temperatures. This endpoint measurement is useful in determining if a vaccine is safe to be administered to a patient, but it does not pinpoint where in the cold chain a vaccine was exposed to excessive heat. With the expansion and technological advancement of cold chain equipment temperature monitoring, it is now possible to remotely estimate VVM status as a vaccine moves through the cold chain. In the present study, we examine the application of the mathematical principles backing VVMs on real, continuous, temperature monitoring data in Africa. Results suggest that exposure to short bursts of hot temperature or long power outages may still allow for safe distribution of affected vaccines. The remaining VVM life calculation could improve managerial visibility into cold chain equipment performance allowing for better data-driven planning and maintenance decisions. [ABSTRACT FROM AUTHOR]

Vacine cold chain assessments conducted in various parts of the world indicate that maintaining equipment at the temperature range recommended by the World Health Organization (WHO) is not always observed. It has been also the case that staff rather prioritize protecting vaccine from heat damage, thus often exposing vaccines to freezing temperatures. As a result, inadvertent freezing of vaccines is a largely overlooked problem all over the world. In a recent systematic review, comparison of the occurrence of freezing temperatures during storage and transport were found to be a global problem occurring both in the resource-rich as well as the resource-limited settings. A vaccine cold chain temperature monitoring study was conducted using standard WHO study protocol with the objective to document potential problems and to identify appropriate control measures. Multiple temperature monitoring devices were used in the study to evaluate user friendliness of these devices and staff attitudes towards them. In general, majority of the time, temperatures were kept between recommended temperature range of 2–8 °C. Temperature variation got wider when products moved from 3PL Laboratory to service points. The wider variation is found at the service points. High temperature excursions were observed or short periods of time while exposures to freezing temperatures were more both higher in number and duration, however, shake test with these vaccines indicated no freeze damage. 91% of staff believed that they did not have the necessary tools to detect if a vaccine had been damaged by a temperature excursion outside the 2–8 °C range, and all staff believed that inclusion of such devices (e.g. vaccine vial monitor) in the system would improve cold chain operations as they have became aware of problematic areas through this study. [ABSTRACT FROM AUTHOR]

Cool water packs are a useful alternative to ice packs for preventing unintentional freezing of vaccines during outreach in some situations. Current guidelines recommend the use of a separate refrigerator for cooling water packs from ambient temperatures to prevent possible heat degradation of adjacent vaccine vials. To investigate whether this additional equipment is necessary, we measured the temperatures that vaccine vials were exposed to when warm water packs were placed next to vials in a refrigerator. We then calculated the effect of repeated vial exposure to those temperatures on vaccine vial monitor status to estimate the impact to the vaccine. Vials were tested in a variety of configurations, varying the number and locations of vials and water packs in the refrigerator. The calculated average percentage life lost during a month of repeated warming ranged from 20.0% to 30.3% for a category 2 (least stable) vaccine vial monitor and from 3.8% to 6.0% for a category 7 (moderate stability) vaccine vial monitor, compared to 17.0% for category 2 vaccine vial monitors and 3.1% for category 7 vaccine vial monitors at a constant 5 °C. The number of vials, number of water packs, and locations of each impacted vial warming and therefore percentage life lost, but the vaccine vial monitor category had a higher impact on the average percentage life lost than any of the other parameters. The results suggest that damage to vaccines from repeated warming over the course of a month is not certain and that cooling water packs in a refrigerator where vaccines are being stored may be a useful practice if safe procedures are established. [ABSTRACT FROM AUTHOR]

Introduction The vaccine vial monitor (VVM) registers cumulative heat exposure on vaccines over time. As low- and lower-middle-income countries transition beyond support from the Global Alliance for Vaccines and Immunization (Gavi), they will assume full responsibility for vaccine financing and procurement. It is unclear to what extent countries transitioning out of Gavi support will continue to include VVMs on their vaccines. This paper aims to systematically review evidence on VVM availability and use in low- and middle-income countries to document factors behind global access to and country demand for VVMs. Such results could help identify actions needed to ensure continued use of VVMs in countries that transition out of Gavi support. Methods We performed a systematic review of electronic databases, reference lists, and grey literature in English and French languages with publication dates from 2005 onwards. The studies included were analyzed for the following outcomes: (1) availability and deployment of VVM-labeled vaccines; (2) VVM practices and perceptions in the immunization system; (3) vaccine introduction and decision-making processes; (4) Gavi graduation and vaccine program sustainability. Results The study found that VVM availability and use was affected by multiple sourcing of vaccines and the extent to which VVM was included in the vaccine specification in the tendering documents when procuring vaccines. Knowledge about VVM and its impact on the EPI program was found to be high among health workers as well as decision-makers. However, the study also found that weak capacity in key national institutions such as NRA and NPA might impact on demand for VVM. As countries take decisions regarding the adoption of new vaccines, factors such as disease burden and vaccine price may assume greater importance than vaccine characteristics and presentation. Finally, the study found that countries rely largely on the advice and recommendations from technical partners such as WHO and PAHO. Conclusion The study concludes that global access to and country demand for VVM are dependent on policy statements and recommendations about VVM by key policy institutions such as WHO and UNICEF. The study also concludes that despite Gavi-eligible countries having access to VVM-labeled vaccines, inclusion is often below 100%. Weak institutional capacity in key national agencies such as NRA and NPA seems to be a contributing factor, while other factors include the procurement of clear national policies on the inclusion of VVM on vaccines, along with the capacity to enforce the policy. Finally, the study concludes that knowledge about VVM and its impact on vaccine program efficiency, safety, and cost is critical for transitioning countries’ continuous demand for VVM. [ABSTRACT FROM AUTHOR]

The Expanded Program on Immunization was designed 40 years ago for two types of vaccines: those that are heat stable but freeze sensitive and those that are stable to freezing but heat labile. A cold chain was developed for transport and storage of such vaccines and established in all countries, despite limited access to resources and electricity in the poorest areas. However, cold chain problems occur in all countries. Recent changes to vaccines and vaccine handling include development and introduction of new vaccines with a wide range of characteristics, improvement of heat stability of several basic vaccines, observation of vaccine freezing as a real threat, development of regulatory pathways for both vaccine development and the supply chain, and emergence of new temperature monitoring devices that can pinpoint and avoid problems. With such tools, public health groups have now encouraged development of vaccines labeled for use in flexible cold chains and these tools should be considered for future systems. [ABSTRACT FROM AUTHOR]

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Two rounds of pulse polio immunization in January and February 2008 were evaluated in rural areas of Dang district. Randomly selected team members of 24% booths and teams working during house to house activity were interviewed. Approximately 78% of eligible children were immunized on booths whereas remaining eligible were covered during house to house activity. In January & February 2008 round, tOPV was used for immunization purpose. Utilizers of booth services received information about these rounds mainly from health worker/anganwadi worker and television. During house to house activity, few unimmunized children were found. Adequate manpower with proper training and community mobilization can improve the coverage.

Abstract: We conducted the first systematic documentation of using oral polio vaccine (OPV) out of the cold chain during national immunization day (NID) campaigns in Mali. Using a crossover intervention design, vaccinators compared the transport of OPV in vaccine carriers with or without ice packs. Vaccine integrity was assured through monitoring vaccine vial monitor (VVM) status. Despite ambient temperatures up to 40°C, none of the VVMs on any of the vials used (n =956) reached their discard point. Over 90% of vaccinators and supervisors preferred conducting NIDs without ice packs. In addition, using OPV out of the cold chain reduced vaccine wastage resulting from melting ice packs causing labels to detach from the vial. [Copyright &y& Elsevier]

Three rounds of pulse polio immunization in January, February and March, 2007 were evaluated in Valsad and Vapi cities. Randomly selected team members of 50% booths and teams working during house to house activity were interviewed. Approximately 80% of eligible children were immunized on booths whereas remaining eligible were covered during house to house activity. In February, 2007 round, mOPV type 1 was first time introduced in Gujarat. Utilizers of booth services received information about these rounds mainly from television and miking. During house to house activity, few unimmunised children were found. Adequate manpower with proper training and community mobilization can improve the coverage. [ABSTRACT FROM AUTHOR]

All members present on booth, working on National Immunization Day during January and February, 2007 were interviewed by using predesigned and pretested questionnaires to assess their awareness regarding type of OPV and VVM in urban areas of Valsad district. Correct identification of trivalent OPV was highest (54.8%) among health staff members working at booths, but for monovalent OPV it was poor (38.7%). More than half (51.6%) of staff members interviewed had not heard of VVM. Awareness was very poor for VVM among those who have heard regarding its function, how to read VVM and when OPV should be discarded. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the failure time of vaccine vial monitor (VVM) used for oral poliovirus vaccine (OPV) at 25 ℃ and 37 ℃. Methods: 160 copies of VVM were produced by a company, the model was QM5D37A, samples were taken from different batches by using the method of random number table . 100 bottles of vaccine were produced by a domestic company, and samples were taken from different batches by using the method of random number table. 160 copies of labels were placed in the incubator at 25 ℃ and 37 ℃, which were used to measure the mutative color of the active region. When the values of color were equal to 40, the color of active region was the same with the reference color, and the VVM was failed. 100 bottles of vaccine were placed in the incubator at 25 ℃ and 37 ℃, which were used to measure the vaccine titer. When total vaccine titer was less than 6.12 CCID50 or vaccine titer of typeⅠ was less than 6.0 CCID50 or vaccine titer of type Ⅲ was less than 5.5 CCID50, the vaccine was failed. We drew the graph of mutative color to calculate the failure time range of VVM According to the graph , we can determine that whether the failure time of VVM was later than the time of vaccines by the data of OPV . Results: The earliest failure time of OPV was 21 days at 25 ℃, and the number of samples was one; The earliest Failure time of VVM was 12.5 days at 25 ℃, and it was less than the earliest failure time of OPV. The earliest failure time of OPV was 4.0 days at 37 ℃, and the number of samples was one; The earliest Failure time of VVM was 3.1 days at 37 ℃, and it was equal to the earliest failure time of OPV. Conclusion: We could know that the failure time of VVM was always earlier than the failure time of vaccines at the same temperatures . The latest failure time of VVM was equal to the earliest failure time of vaccines at 37 ℃. All of the failure times of samples were earlier than that of vaccines at 25 ℃.