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PubMed2006

A vaccine cold chain freezing study in PNG highlights technology needs for hot climate countries.

Fourteen data loggers were packed with vaccine vials at the national vaccine store, Port Moresby, Papua New Guinea (PNG), and sent to peripheral locations in the health system. The temperatures that the data loggers recorded during their passage along the cold chain indicated that heat damage was unlikely, but that all vials were exposed to freezing temperatures at some time. The commonest place where freezing conditions existed was during transport. The freezing conditions were likely induced by packing the vials too close to the ice packs that were themselves too cold, and with insufficient insulation between them. This situation was rectified and a repeat dispatch of data loggers demonstrated that the system had indeed been rectified. Avoiding freeze damage becomes even more important as the price of freeze-sensitive vaccines increases with the introduction of more multiple-antigen vaccines. This low-cost high-tech method of evaluating the cold chain function is highly recommended for developing and industrialized nations and should be used on a regular basis to check the integrity of the vaccine cold chain. The study highlights the need for technological solutions to avoid vaccine freezing, particularly in hot climate countries.

Drug Stability↗
PubMed1993

The integrity of the vaccine cold chain in the Hunter area of New South Wales.

Two surveys investigated the integrity of the cold chain from the State Vaccine Centre in Sydney to immunisation centres in the Hunter Area. The first examined the extent to which temperatures of vaccines in transit during November 1991 exceeded 10 degrees C. Temperatures had exceeded 10 degrees C for unknown periods. The cumulative effect of such cold-chain impairment and reported inadequacies in vaccine maintenance and handling by the State Vaccine Centre cannot be estimated. The second survey examined the effectiveness of refrigerators used to store vaccines by Hunter area councils and community health centres and a random sample of general practices in the Hunter. Only 29 per cent of council and community health refrigerators and 22 per cent of general practice refrigerators were effective. While the second survey described the storage environment of particular vaccines for a very short period on one day only, maintenance of such conditions could compromise the integrity of stored vaccines.

Cold Temperature↗
PubMed1990

[Evaluation of the cold chain and follow-up of the potency of the antimeasles vaccine in the field].

In order to evaluate the quality of the measles vaccine, it was carried out a study in three states of Mexico (Durango, San Luis Potosi and Yucatan) during the intensive vaccination campaign in 1986. Edmonston-Zagreb measles vaccine vials were obtained from the different administrative-sanitary levels of the Ministry of Health in Mexico. Interviews were performed to the vaccine responsibles. Questionnaires had the following aspects of the cold chain: storage, preservation, control and transport of measles vaccine. Answers were evaluated through a system, where 100% indicated the necessary and sufficient level to get a good operating of the cold chain. The vaccine potency did not have variations under the minimum titre recommended for the World Health Organization (W.H.O.). The three states had the following compliment of the cold chain norms: 1) Central state level: 83% in storage, 80% in preservation, 100% in control and 100% in transport norms; 2) Regional level (jurisdiction): 87% in storage, 51% in preservation, 93% in control and 100% in transport norms; 3) Local level: 83% in storage, 64% in preservation, 83% in control and 33% in transport norms.

Cold Temperature↗
PubMed1996

Live viral vaccine potency: an index for assessing the cold chain system.

This study was carried out in the states of Lagos, Oyo, Osun, Nigeria and was designed to assess the efficiency of the cold chain and the potency of the vaccines from the National Cold Store through to the vaccination centres. Storage equipment was inspected and oral polio, measles and yellow fever vaccines were tested for potency. All 27 centres studied had adequately trained staff and storage was shown to be adequate at the National and State Cold Store Level. However, vaccines were adversely affected at the local Government Area Cold Store and Vaccination Centre Levels. Losses of potency of vaccines were shown: loss of titre of oral polio and yellow fever vaccine (0.03-0.9 log) was less than that of the measles vaccines (0.1-2.7 log). This was ascribed to thawing and refreezing due to equipment failure, to intermittent power supply in the absence of standby generators and mishandling of vaccines in the vaccine centres. This study revealed inadequacies at the Local Government Area and Vaccination Centre level. The cold chain should be examined in the remaining states of Nigeria and the inadequacies corrected.

Cold Temperature↗
PubMed2006

Immunogenicity of a locally produced hepatitis B vaccine with the birth dose stored outside the cold chain in rural Vietnam.

The heat stability of hepatitis B vaccine (HepB vaccine) should enable its storage outside the cold chain (OCC), increasing access to the birth dose in areas lacking refrigeration. We compared the immunogenicity of a locally produced vaccine among infants who received three doses stored within the cold chain (n = 358) or for whom the first dose was stored OCC for up to one month (n = 748). Serum was collected from these infants at age 9-18 months. The vaccine was protective in 80.3% of all infants. There were no differences in the prevalence of a protective level of antibody or antibody titer among groups of infants according to storage strategy. Differences in antibody titer between certain groups of infants could be explained by different vaccination schedules. Where birth dose coverage will be improved, HepB vaccine can be taken OCC for up to one month without affecting its immunogenicity.

Cold Temperature↗
PubMed2004

[Maintenance of cold chain for the delivery of immunobiological drugs by the indicators of heating and freezing controls].

The paper deals with an objective evaluation of a qualitative storage of immunobiological drugs including all stages of "cold chain". The results of technological research and of designing related with constructing a system of indicators for monitoring the temperature regime to maintain the "cold chain" functioning are presented. The suggested devices are comparatively described.

Drug Stability↗
PubMedDate not supplied

[Vaccine storage cold chain at primary care centers in one area of Madrid: keeping the chain intact and degree of knowledge].

BACKGROUND: Vaccines are heat-labile medications, and to guarantee their immunogenicity and safeguarding effectiveness as part of immunization programs, it is absolutely essential that the "Cold Chain" go unbroken. Fundamental thereto is the personnel responsible for the vaccines, who must know the stability-related characteristics of each preparation so as to prevent handling errors. The purpose of this study was that of ascertaining how the cold chain is kept intact in primary care systems in one healthcare area of the Autonomous Community of Madrid, as well as determining the degree of information possessed by those responsible for vaccines as far as their heat-stability is concerned. METHODS: A cross-sectional study has been made at 46 primary care vaccination points. The data was gathered by means of a personal interview by one single researcher. RESULTS: The participation rate was 93.5% (43/46). In all cases, there was a maximum and minimum thermometer and monthly temperature record. An unsuitable temperature was found in three cases (6.97%). The percentage of professionals who were aware of the effect freezing has on vaccines varied greatly: 53.5%, 51.2%, 44.2% and 53.5% for diphtheria-tetanus-pertussis (DTP), hepatitis B (HBV), oral polio (OPV) and measles-mumps-rubella (MMR) respectively. And only 32% were familiar with the shake test. CONCLUSION: The professionals were found to be properly trained regarding the effect which high temperatures have on vaccines, but it is necessary for their training with regard to the instability of adsorbed preparations when frozen must be further strengthened.

Adult↗
PubMed2019

Cold chain and virus-free oral polio booster vaccine made in lettuce chloroplasts confers protection against all three poliovirus serotypes.

To prevent vaccine-associated paralytic poliomyelitis, WHO recommended withdrawal of Oral Polio Vaccine (Serotype-2) and a single dose of Inactivated Poliovirus Vaccine (IPV). IPV however is expensive, requires cold chain, injections and offers limited intestinal mucosal immunity, essential to prevent polio reinfection in countries with open sewer system. To date, there is no virus-free and cold chain-free polio vaccine capable of inducing robust mucosal immunity. We report here a novel low-cost, cold chain/poliovirus-free, booster vaccine using poliovirus capsid protein (VP1, conserved in all serotypes) fused with cholera non-toxic B subunit (CTB) expressed in lettuce chloroplasts. PCR using unique primer sets confirmed site-specific integration of CTB-VP1 transgene cassettes. Absence of the native chloroplast genome in Southern blots confirmed homoplasmy. Codon optimization of the VP1 coding sequence enhanced its expression 9-15-fold in chloroplasts. GM1-ganglioside receptor-binding ELISA confirmed pentamer assembly of CTB-VP1 fusion protein, fulfilling a key requirement for oral antigen delivery through gut epithelium. Transmission Electron Microscope images and hydrodynamic radius analysis confirmed VP1-VLPs of 22.3&#xa0;nm size. Mice primed with IPV and boosted three times with lyophilized plant cells expressing CTB-VP1co, formulated with plant-derived oral adjuvants, enhanced VP1-specific IgG1, VP1-IgA titres and neutralization (80%-100% seropositivity of Sabin-1, 2, 3). In contrast, IPV single dose resulted in <50% VP1-IgG1 and negligible VP1-IgA titres, poor neutralization and seropositivity (<20%, <40% Sabin 1,2). Mice orally boosted with CTB-VP1co, without IPV priming, failed to produce any protective neutralizing antibody. Because global population is receiving IPV single dose, booster vaccine free of poliovirus or cold chain offers a timely low-cost solution to eradicate polio.

Animals↗
PubMed1994

Use of cold-chain to assess vaccine exposure to adverse temperatures in rural Tanzania.

A study was carried out in Tabora region to determine the magnitude of exposure of vaccines to adverse temperatures using the Cold Chain Monitors (CCMs). Except for refrigerators in the regional hospital, almost all refrigerators were found to be exposed to adverse temperature. The RAK type of refrigerators were found to be more exposed to adverse temperature than the RCW type. While an alternative type of refrigerator suitable for tropical countries is being sought there is a need of focusing more attention on improving cold chain system in the peripheral facilities.

Evaluation Studies as Topic↗
PubMed2001

[Cold chain --the concept of traceability-- practical applications].

Traceability makes it possible to monitor the properties of a foodstuff in general and its safety in particular. Based on the "refrigerated trio" concept developed by André Monvoisin, cold chain implementation conditions are examinated, with emphasis on the following three aspects, a safe product and early and continuous application of refrigeration. The TTT and PPP theories are presented. Following an overview of the French Academy of Medicine and the National Consumer Centre's recommendations, non compliance with the cold chain at household refrigerator level is discussed along with control equipment for refrigerators and products. Various indicators and integrators are presented and their described. Time-temperature integrators are examined in depth. In the conclusion, the authors stress the need to restore consumer confidence following recent foof-safety scares.

Food Handling↗
PubMed2003

Guidelines for maintaining and managing the vaccine cold chain.

In February 2002, the Advisory Committee on Immunization Practices (ACIP) and American Academy of Family Physicians (AAFP) released their revised General Recommendations on Immunization, which included recommendations on the storage and handling of immunobiologics. Because of increased concern over the potential for errors with the vaccine cold chain (i.e., maintaining proper vaccine temperatures during storage and handling to preserve potency), this notice advises vaccine providers of the importance of proper cold chain management practices. This report describes proper storage units and storage temperatures, outlines appropriate temperature-monitoring practices, and recommends steps for evaluating a temperature-monitoring program. The success of efforts against vaccine-preventable diseases is attributable in part to proper storage and handling of vaccines. Exposure of vaccines to temperatures outside the recommended ranges can affect potency adversely, thereby reducing protection from vaccine-preventable diseases. Good practices to maintain proper vaccine storage and handling can ensure that the full benefit of immunization is realized.

Cold Temperature↗
PubMed2003

Crohn's disease: the cold chain hypothesis.

Crohn's disease is the result of an abnormal immune response of the gut mucosa triggered by one or more environmental risk factors in people with predisposing gene variations, including CARD15 mutations. Epidemiological data allow assessment of familial environmental risk factors related to western lifestyle, diet, bacteria, and domestic hygiene. All findings point to refrigeration as a potential risk factor for Crohn's disease. Furthermore, cold-chain development paralleled the outbreak of Crohn's disease during the 20th century. The cold chain hypothesis suggests that psychrotrophic bacteria such as Yersinia spp and Listeria spp contribute to the disease. These bacteria have been identified in Crohn's disease lesions and we discuss their pathogenic properties with respect to our knowledge of the disease. From a molecular perspective, we postulate that the disease is a result of a defect in host recognition by pathogenic bacterial components that usually escape the immune response (eg, Yop molecules), which results in an excessive host response to these bacteria.

Carrier Proteins↗
PubMed1993

The value of potency testing of poliomyelitis and measles vaccines as an integral part of cold chain surveillance.

The Virology Division in the Institute for Medical Research, Kuala Lumpur, Malaysia performs potency tests on oral polio vaccines and live attenuated measles vaccines. Since these potency tests were introduced in 1981 a total of 752 tests have been performed on vaccine samples from peripheral immunization centers. Of 165 representative vaccine samples sent for potency evaluation after a cold chain breakdown 154 (87%) passed minimum potency requirements recommended for immunization of infants. In the absence of potency evaluation, those vaccines exposed to temperatures higher than the recommended storage range would be discarded, perhaps resulting in unnecessary wastage and economic loss. Results of the vaccine potency evaluation has enabled health authorities to indirectly monitor cold chain efficiency and ensure the high quality of viral vaccines used in our childhood immunization program.

Animals↗
PubMed2006

Exposure to heat and freezing in the vaccine cold chain in Thailand.

This study investigated exposure to heat and freezing of vaccines used in Thailand's National Immunization Program. Cold chain temperatures on 48 randomly selected shipment routes nationwide were monitored. Measles and hepatitis B vaccines were despatched with recording devices and subsequently tested. The study found that extremes of cold appear to be the more significant problem. Heat exposure was relatively brief and not at very high temperatures, so vaccine deterioration was unlikely, as was confirmed by measles vaccine testing. Exposure to temperatures below -0.5 degrees C was widespread, which would be expected to damage hepatitis B vaccine, but shake tests did not detect damage.

Cold Temperature↗
PubMed2001

Detection of St. Louis encephalitis and western equine encephalomyelitis RNA in mosquitoes tested without maintenance of a cold chain.

Western equine encephalomyelitis and St. Louis encephalitis viral RNA can be detected 20 days after death of infected Culex tarsalis in the absence of a cold chain. Viral RNA was detected with the reverse transcription-polymerase chain reaction in mosquitoes infected either parenterally or perorally in the laboratory and then killed and held for up to 20 days at 27 degrees C. Cell culture assay and in situ enzyme immunoassay did not detect infectious virus in the same mosquitoes.

Animals↗
PubMed2003

Cold chain monitoring of OPV at transit levels in India: correlation of VVM and potency status.

We have conducted a study to analyze monitoring of the cold chain of 674 OPV field samples collected at four different levels of vaccine distribution viz., immunization clinics, district stores, hospitals and Primary Health Centers (PHC) from states of Uttar Pradesh, Madhya Pradesh, and Delhi. The study design included: collection and scoring of vaccine vial monitor (VVM) status of the samples and testing for total oral polio virus concentration (TOPV) by standard WHO protocol. Ten samples each were exposed to 25 degrees C and 37 degrees C, and 10 samples as controls were kept at -20 degrees C. VVM were scored daily till they attained grade 4 and each sample was subsequently subjected to potency testing for individual polio serotypes 1, 2 and 3, and TOPV. Of the 674 samples tested it was observed that: samples from immunization clinics and district stores had an acceptable VVM score of grade 1 and 2; however the probable risk that a sub potent vaccine could have been administered was 2.15%. In 2.5% samples received from district stores vaccine had a VVM score of grade 3 (i.e., discard point), although vaccine when tested was found to be potent (i.e., leading to the vaccine wastage). With exposure to higher temperatures, VVM changed score to grade 2 and 3 when the vaccine was kept at 25 degrees C/37 degrees C, and the titres of individual serotypes 1, 2 and 3 and TOPV were beyond the acceptable limits. Important observations at the different levels of vaccine distribution network and correlation of VVM and potency status of OPV are discussed in the paper which will be of help to the EPI program managers at different transit levels.

Cold Temperature↗
PubMed1992

The cold chain from manufacturer to vaccinator: experiments and experiences.

Biological substances are temperature sensitive. Most vaccines must be constantly kept at temperatures between +2 to +8 degrees C (cold chain). To test the conditions of a long distance transport of vaccines in an 80 l cool box the temperature in the correctly packed box was monitored. The temperature remained between zero and +8 degrees C for more than 90 h, the ambient temperature during this test reached 37 degrees C for 5 h. It can be concluded that the currently used transport boxes are well suited for safe transport of sensitive products such as vaccines.

Cryopreservation↗