SEARCH · PubMed Health

Results for “Cold Chain”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources

PubMed2001

The use of antigen-capture enzyme-linked immunosorbent assay (ELISA) for the diagnosis of rinderpest and peste des petits ruminants in ethiopia.

Rinderpest had been reported in most parts of Ethiopia when the Pan African Rinderpest Campaign (PARC) was launched. As a result of intensive disease investigation and strategic vaccination, most parts of the country are now considered provisionally free, and widespread vaccination has been replaced by clinical and serological surveillance. Details of any episodes of disease are recorded and followed up after laboratory confirmation of suspected cass using antigen-capture ELISA. This paper is based on observations on the performance of the antigen detection ELISA compared to the agar gel immunodiffusion (AGID) test, which also differentiates rinderpest from peste des petits ruminants (PPR). The stability of the specific viral antigen was monitored for 4 days, and rinderpest and PPR antigens were still detected, depending on the type of specimen. Antigen capture ELISA is more rapid, sensitive and virus specific than the AGID. Even if the cold chain of the specimen is compromised for a day or two during sample collection and submission, the specimen may still be suitable for testing by ELISA.

Animals↗

PubMed2000

An outbreak in Italy of botulism associated with a dessert made with mascarpone cream cheese.

In the late 1996, an outbreak of botulism affected eight young people (age of patients ranged from 6 to 23 years) in Italy. The onset of the illness was the same for all of these patients: gastrointestinal symptoms (nausea and vomiting) followed by neurologic symptoms. The most common neurologic symptoms were dysphagia, respiratory failure (100%), diplopia (87%), dysarthria, ptosis (75%) and mydriasis (50%). All patients required mechanical ventilation. Botulinum toxin was detected from two of respectively five sera and six stool samples analysed, while spores of Clostridium botulinum type A were recovered from all patient' faeces. The epidemiological investigation led to suspect a commercial cream cheese ('mascarpone') as a source of botulinum toxin: indeed, it had been eaten by all the patients before onset of the symptoms, either alone or as the (uncooked) ingredient of a dessert, 'tiramisù'. Botulinum toxin type A was found in the 'tiramisù' leftover consumed by two patients and in some mascarpone cheese samples collected from the same retail stores where the other patients had previously bought their cheeses. A break in the cold-chain at the retail has likely caused germination of C. botulinum spores contaminating the products, with subsequent production of the toxin. One of the patients died, while the others recovered very slowly. Prompt international alerting and recall of the mascarpone cheese prevented the spread of the outbreak due to the wide range of distribution, demonstrating the importance of a rapid surveillance system. None of the people complaining of symptoms after the public alert resulted positive for botulinum spores and toxin.

Adolescent↗

PubMed2003

Optimization of an alum-adsorbed vaccine powder formulation for epidermal powder immunization.

PURPOSE: To develop stable and effective aluminum salt (alum)-adsorbed vaccine powder formulations for epidermal powder immunization (EPI) via a spray freeze-drying (SFD) process. METHODS: Powder properties were determined using particle size analysis, tap density, and scanning electron microscopy. Alum coagulation was monitored via optical microscopy and particle sedimentation. Protein analysis was determined by the BCA protein assay, SDS-PAGE, and an enzyme immunoassay. In vivo immunogenicity and skin reactogenicity were performed on hairless guinea pigs and pigs, respectively. RESULTS: SFD of hepatitis B surface antigen (HBsAg) adsorbed to aluminum hydroxide or aluminum phosphate using an excipient combination of trehalose/mannitol/dextran produced vaccine powders of dense particles and satisfactory powder flowability and hygroscopicity. This formulation also offered excellent long-term stability to the powder and the antigen. The two most important factors influencing alum particle coagulation are the freezing rate and the concentration of aluminum in the liquid formulation for SFD. The SFD vaccines, when delivered to hairless guinea pigs by EPI or injected intramuscularly after reconstitution, were as immunogenic as the original liquid vaccine. A further study showed that EPI with SFD alum-adsorbed diphtheria-tetanus toxoid vaccine was well tolerated, whereas needle injection of the liquid formulation caused persistent granuloma. CONCLUSIONS: Stabilization of alum-adsorbed vaccine by SFD has important implications in extending vaccination to areas lacking a cold chain for transportation and storage and may also accelerate the development of new immunization technologies such as EPI.

Adsorption↗

PubMedDate not supplied

The current status of major tick borne diseases in Zambia.

Tick-borne diseases occurring in Zambia are assuming more importance as they continue to be a major economic problem not only in Zambia, but in many parts of Eastern, Southern and Central Africa. The current control methods, which include the use of toxic acaricides to kill ticks, and the virulent sporozoite infection and treatment method have limitations. Recombinant vaccines, currently in their experimental stages, offer hope for the future. The use of acaricides is hampered by the development of acaricide resistance and live vaccines are dependent on cold chain facilities, which are a formidable obstacle in the poorly developed infrastructure in parts of Zambia where the vaccine is most needed. Amidst these drawbacks are the results of the recent research on parasites and vector recombinant vaccines which promise to circumvent these problems. The history, current status and attitudes regarding the control of these diseases, taking into account their complexity, are reviewed. The establishment of the well-designed Central Veterinary Research Institute (CVRI) and Japanese International Cooperation Agency (JICA) sponsored veterinary school, both have a potential for high quality research, with access to a wealth of specimens a veritable goldmine of research material. It is thus hoped that this review will stimulate the desire to maximize the value of the tick and tick-borne disease research in both Zambia and the international research community.

Animals↗

PubMed2001

Tetanus IgG antibody levels in children aged 12 to 47 months in Turkey.

Tetanus is a serious disease with high mortality, which is very difficult to treat but can be prevented easily by vaccination. The number of tetanus cases reported in Turkey was 42 in 1996 and 51 in 1997. This study was carried out on children aged 12 to 47 months who have vaccination cards in the No. l Health Centre in Batikent district in Ankara, Turkey. Forty-one of the children had received 3 doses (Group 1) of tetanus vaccine, and 47 of them had received 4 doses of the vaccine (Group 2). Anti-toxoid IgG antibody in blood sera was quantified by using the enzyme-linked immunosorbent assay technique. In Group 1, antibody levels more than 0.01 IU/mL were found in 47%, 43%, and 45% of blood sera of children aged 12 to 23 months, 24 to 35 months, and 36 to 47 months, respectively. These rates in Group 2 were found to be 91%, 88%, and 60%, respectively. The protective antibody response (>1 IU/mL) was found to be higher for children in Group 2 than in Group 1, but both rates declined with age. Checking immunization status periodically and giving vaccine doses as required are essential to increase the antibody response. Further, it is a must in developing countries where vaccination efforts are hindered by cold-chain problems, underoptimum application practice, and high prevalence of concomitant infections.

Age Distribution↗

PubMed2002

Use of polarography as a quality-control method for determining diacetyl in citrus and vegetable juices, yoghurt and butter.

The determination of diacetyl permits the detection of microbial growth in the processing of citrus fruit before the appearance of other organoleptic, chemical or microbiological changes. It also makes it possible to detect a break in the cold chain during distribution and sale. The study proposed a polarographic method for the determination of diacetyl that allowed routine analysis with the aim of detecting possible contamination in the citrus juice manufacturing chain (orange and orange-carrot). The analytical performance of the method in terms of a linearity from 0 to 960 microg ml(-1), a recovery of 97 to 98%, a precision of 3.2 to 4.8%, and a sensitivity of 0.2 ng ml(-1) for juices indicated the robustness of the method. The same method was also applied to butter and yoghurt with detection limits of and 0.4 ng g(-1).

Beverages↗

PubMed2000

Ukraine, 1992: first assessment of diphtheria vaccine effectiveness during the recent resurgence of diphtheria in the Former Soviet Union.

A case-control study in Ukraine provided the first data on the field effectiveness of Russian-produced vaccine during the 1990 diphtheria resurgence in the former Soviet Union. For each of 262 diphtheria cases <15 years of age who were reported from January through October 1992, 2 controls, matched by age and clinic, were selected. The effectiveness of three doses of diphtheria vaccine was 98.2% (95% confidence interval: 90.3-99.9). Among controls, 84% had received three or more vaccinations by 2 years of age. These results suggest that the following five hypothesized causes of the outbreak appeared unlikely: appearance of a new "mutant" diphtheria strain, low potency of the Russian-produced diphtheria vaccine, inadequate cold chain, poor host immunogenicity due to radiation exposure from Chernobyl, and low routine childhood vaccination coverage. It is concluded that initial priority for scarce resources for controlling this outbreak should be placed on vaccination of persons susceptible to diphtheria (e.g., adults) rather than revaccination of children.

Adolescent↗

PubMed2003

The challenges and strategies for laboratory diagnosis of measles in an international setting.

Serum-based measles-specific IgM EIAs are the recommended laboratory assays for diagnosis of acute measles infections and appear to be sufficient for measles control programs. However, serum samples are not ideal for molecular characterization of measles virus. Although neither laboratory nor field-based diagnostic tests that rival the EIAs have been developed, laboratory surveillance could be improved if specimen collection were simplified. Ideally the collection method should be noninvasive, have no requirement for a cold chain, and/or have no requirement for technically sophisticated equipment. Two alternative specimen collection technologies appear promising and can be used for both diagnostics and for collecting pertinent genotyping information: oral fluid and filter paper collection methods. These methods are compared along with their respective utilities in supporting measles diagnosis and strain surveillance.

Antibodies, Viral↗

PubMed1998

Outbreak of paralytic poliomyelitis in Albania, 1996: high attack rate among adults and apparent interruption of transmission following nationwide mass vaccination.

After >10 years without detection of any cases of wild virus-associated poliomyelitis, a large outbreak of poliomyelitis occurred in Albania in 1996. A total of 138 paralytic cases occurred, of which 16 (12%) were fatal. The outbreak was due to wild poliovirus type 1, isolated from 69 cases. An attack rate of 10 per 100,000 population was observed among adults aged 19-25 years who were born during a time of declining wild poliovirus circulation and had been vaccinated with two doses of monovalent oral poliovirus vaccines (OPVs) that may have been exposed to ambient temperatures for prolonged periods. Control of the epidemic was achieved by two rounds of mass vaccination with trivalent oral poliovirus vaccine targeted to persons aged 0-50 years. This outbreak underscores the ongoing threat of importation of wild poliovirus into European countries, the importance of delivering potent vaccine through an adequate cold chain, and the effectiveness of national OPV mass vaccination campaigns for outbreak control.

Adolescent↗

PubMedDate not supplied

Expanded Programme on Immunization in Thailand.

In 1976, despite a 20-year immunization program, vaccine-preventable diseases (other than smallpox) remained important causes of morbidity and mortality in Thailand. Three major problems were identified: a lack of proper target age groups, inadequate vaccination coverage, and a defective cold chain. The National Expanded Programme on Immunization (EPI), focusing on diphtheria, pertussis, tetanus, poliomyelitis, measles, and tuberculosis, was initiated on a nationwide basis in 1977. Data indicate that the program has reduced morbidity and mortality from most vaccine-preventable diseases in Thailand. The goal of the EPI is to have every eligible child fully immunized with efficacious vaccines by 1990. Strategies have been developed and are being used by the "accelerated EPI" to achieve this goal.

Child↗

PubMedDate not supplied

Vaccine distribution: an operations research study.

The implementation of an immunization program in rural areas is affected by lacunae in the vaccine distribution system. A study conducted in India identified the extent to which irregular supply of vaccines has affected the immunization program. This study also identified other problem areas, such as a faulty cold chain and the need for an improved monitoring and control system and for better supervision. A model was designed to represent the immunization program and was used to assess the performance of the system under different supply conditions and operational policies. The study identified a number of improvements that could be made in the vaccine distribution system.

Humans↗

PubMedDate not supplied

Selective primary health care: strategies for control of disease in the developing world. IV. Measles.

Measles, a highly contagious viral disease, kills several hundred thousand infants and young children yearly. Essentially all children will become infected; at least 1% of those living in developing countries will die unless protected by immunization. In urban areas, peak incidence occurs in those younger than three years. The youngest and most undernourished children suffer the most severe complications and the highest risk of death. Diarrhea, malnutrition, pneumonia, and blindness associated with vitamin A deficiency are the worst complications. The infection is preventable by the timely administration of a potent vaccine. This endeavor requires a well-managed technical and administrative network that remains difficult to organize in many areas of the world. The vaccine is efficacious and has few adverse effects but must be provided to children during the short interval between loss of transplacentally acquired antibodies and the acquisition of natural infection. The improvements in heat stability of the vaccine increase the likelihood of providing potent vaccine, but a well-managed cold chain remains a prerequisite for any successful immunization program. Health education, improved management skills, publicity, and community support are all important factors for ultimately preventing the morbidity and mortality from this disease.

Adolescent↗

PubMedDate not supplied

The control of measles in tropical Africa: a review of past and present efforts.

Measles in tropical Africa is endemic and cyclical, with a high incidence that usually peaks during the dry seasons. Measles may be a contributing factor in 10% of all deaths among African children. Several problems have hindered measles immunization programs in Africa; these include difficulties in maintaining the cold chain, poor epidemiologic surveillance, and the logistical problems involved in reaching a population that is 80% rural. The United States Agency for International Development and the World Health Organization both have programs that are helping to increase immunization coverage and to solve the problems just mentioned. Many countries have begun to train their own personnel to administer immunization programs. However, because of limited staff and equipment, a high birth rate, and an uncertain social situation, no firm predictions can be made concerning the permanent control of measles in tropical Africa.

Africa↗

PubMedDate not supplied

Mass vaccination against poliomyelitis in Mexico.

In 1959, oral poliovirus vaccine ( OPV ) was introduced as an antiepidemic measure in Mexico. As in many other developing countries, the vaccine was misused, coverages achieved were often poor, and an adequate cold chain was lacking. However, in 1972 a mass campaign reached 70% of children younger than five years of age, and consequently the reported cases declined sharply from 1.9 to 0.4 per 100,000 population. Due to economic restrictions, only single doses of monovalent type 1 OPV were administered to 80% of the target population in 1981, 1982, and 1983. The present incidence of poliomyelitis of 0.1 per 100,000 population represents a 96.7% reduction from the rate during the prevaccine era, when the annual average rate was 4.26 per 100,000. The present aim of poliomyelitis control is to maintain and decrease the present incidence of disease. Future plans are to continue mass vaccination in an attempt to reach small and isolated villages that have been without vaccination and limit possible rural foci of wild poliovirus.

Humans↗

PubMed2006

Immunization to protect the US Armed Forces: heritage, current practice, and prospects.

Americans serving with the US Armed Forces need protection from the dangerous infections that they can contract during training, based on occupation, during overseas deployment, or because of underlying health status. For over 230 years, the military health-care system has immunized troops to protect them personally and to help them accomplish their missions. Military researchers have invented, developed, and improved vaccines and immunization delivery methods against more than 20 diseases. This article consolidates content from several previous historical reviews, adds additional sources, and cites primary literature regarding military contributions and accomplishments. Discussion emphasizes smallpox, typhoid fever, tetanus, influenza, meningococcal disease, adenovirus, yellow fever, pneumococcal disease, and anthrax. Delivery issues include documentation, simultaneous immunization, seroscreening, safety surveillance, jet injection, and cold-chain management. Immunization policies for each major US conflict are described. Military immunization programs need to be individualized on the basis of personal contraindications and prior immunity. The proper conduct of military immunization programs respects the need for detailed education of military personnel, maximizes quality in immunization delivery, and supports quality clinical care to prevent and treat adverse events after immunization. Military immunization programs maintain the health of soldiers, marines, sailors, airmen, and coast guardsmen, the resources most critical to military success.

Bacterial Vaccines↗

PubMed2004

High prevalence in Switzerland of pure red-cell aplasia due to anti-erythropoietin antibodies in chronic dialysis patients: report of five cases.

BACKGROUND: Pure red-cell aplasia (PRCA) after erythropoietin (Epo) administration due to the appearance of neutralizing anti-Epo antibodies has been reported in over 200 cases between 1998 and 2002. However, large intercountry disparities were observed in the occurrence of this syndrome. METHODS: On behalf of the Swiss Society of Nephrology, a survey was conducted in all the dialysis units of Switzerland in order to collect information on the occurrence, diagnostic and evolution data of the cases observed. A questionnaire was send to the nephrologists in charge of each of the 69 dialysis units in January 2003. The clinical and biological data of the suspected cases were analysed and compared with the data provided to health authorities and pharmaceutical companies. RESULTS: A total of five cases were identified as true PRCA with demonstrated positive anti-Epo antibodies. They occurred between November 1998 and February 2002, were all treated by haemodialysis and had received Epo subcutaneously. The median appearance time of refractory anaemia after Epo initiation was 10 months (range: 7-54 months). Two cases had been treated exclusively with epoietin-alpha, one solely with epoietin-beta and the two others with a combination of both. With five cases out of a total of about 2500 dialysis patients and 2300 Epo-treated dialysis patients or an exposure rate to Epo of 9900 dialysis patient-years during a 4.3 year period, this prevalence is among the highest of those reported in European countries. CONCLUSIONS: The prevalence of PRCA after Epo administration in dialysis patients appears particularly high in Switzerland. Among the potential explanations, the most plausible are the high percentage of dialysis patients treated with Epo, the almost exclusive subcutaneous administration, the larger market distribution of the epoietin-alpha brand, the eventual disruption of the cold chain and the setting-up of a systematic national survey.

Aged↗

PubMed2005

Instability of lopinavir/ritonavir capsules at ambient temperatures in sub-Saharan Africa: relevance to WHO antiretroviral guidelines.

WHO recommends lopinavir/ritonavir as an antiretroviral option in resource-limited countries. Lopinavir/ritonavir is recommended to be stored at 2-8 degrees C until dispensing, and afterwards, may be kept at < or = 25 degrees C for < or = 2 months. Anticipating lopinavir/ritonavir use in countries lacking adequate cold-chains, we assessed its physical and chemical stability at 35 and 45 degrees C. Although maintaining chemical stability for 4 weeks at 35 degrees C, at 45 degrees C the capsules clumped after 7 days, supporting a need for more temperature-stable formulations for hotter climates.

Africa South of the Sahara↗

PubMed2006

The stability of micro-organisms preserved in LENTICULE discs, demonstrated by repeat sample distributions of the EQUAL Scheme for Indicator Organisms (water microbiology).

AIMS: To demonstrate the stability of microorganisms preserved in LENTICULE discs, employed by the EQUAL Scheme for Indicator Organisms. METHODS AND RESULTS: Five sample batches containing several indicator organism parameters were each despatched in two separate distributions at intervals of up to 24 months apart. A comparison of participants' median counts and bar charts of their cumulated results was then made. CONCLUSIONS: The results demonstrated that LENTICULE discs provided a remarkably stable preparation format for the maintenance of viable organisms in reproducible numbers. SIGNIFICANCE AND IMPACT OF THE STUDY: Complex mixtures of organisms can be maintained in stable numbers for extended periods of time at a freezer temperature of -20 degrees C and satisfactorily transported without the requirement for cold chain conditions.

Clostridium perfringens↗