Cold Chain Failure: Lessons Learned From 2 Cases

Two case studies in cold chain failure offer insights into preventing catastrophic public health consequences through simple precautions.

In the past, failures of vaccine storage have led to expensive product losses and the administration of compromised vaccines to patients. High-profile cases of compromised vaccines due to improper temperature regulation have been recorded in both Canada and the United States.

In May 2002, the temperatures of 3 refrigerators for storing vaccines at a large public health office in Alberta, Canada were left unmonitored for 20 days. As a result, many vaccines had to be readministered to patients. In addition, a large store of vaccines were lost, including DaPTP-Hib (diptheria, acellular pertussis, tetanus, polio, Haemophilus influenzae type B), MMR (measles, mumps, rubella), varicella, and meningococcal vaccines.

The resulting negative media attention and public concern about vaccine safety reduced confidence in Canadian public health authorities. To remedy the problem of substandard vaccine storage, the public health office clarified responsibilities related to vaccine storage and educated staffers on storage temperature checks. Additionally, an annual cold chain audit was instituted and staff were educated on continuous temperature monitoring.

Several infrastructure problems were identified and remedied, as well. For instance, in the past, some vaccines had been stored in bar-style refrigerators, which are incompatible with vaccine storage consistent with World Health Organization cold storage guidelines. Bar-style refrigerators were subsequently replaced with laboratory-grade vaccine refrigerators. Monitoring and notification systems were put in place, as each refrigerator was outfitted with temperature monitoring systems. As a failsafe, battery back-up power and generators were also installed at public health facilities.

Unfortunately, cold chain failures are not limited to Canada. In Arizona, between 2007 and 2012, the state Vaccines for Children Program experienced challenges in maintaining effective vaccine storage. Clinics also used the low-cost bar-style refrigerators, which caused inconsistent monitoring of the refrigerator temperatures. In addition, when vaccines were exposed to out-of-range temperatures, the manufacturer was never called to ensure that the vaccine was still viable.

On more than 30 occasions at one site, hepatitis B vaccines and hepatitis immunoglobulins, both intended for use in newborns, were accidentally frozen. As a result, more than 200 parents received letters advising that their children be revaccinated.

After these critical failures, refrigerators at a total of 45 provider sites enrolled in the Arizona vaccination program were investigated by the Office of the Inspector General (OIG) using continuous temperature monitoring equipment. According to an OIG report, more than three-fourths (76%) of practice site refrigerators registered at least 5 hours of out-of-range temperatures over 2 weeks.

Today, failures like these can be prevented through digital temperature monitoring devices that enable pharmacies and other health sites to continuously record refrigerator temperatures. These continuous data loggers can also alert health care professionals when temperatures are changing rapidly, which prevents product loss and safeguards the supply of vaccines to protect public health and reduce the incidence of vaccine-preventable illnesses.

References

• Henneigh L. How a cold chain nightmare led to long-term solutions. http://www.health.alberta.ca/documents/WCIF2014-PPT28-Henneigh-Cold-Chain.pdf. Accessed March 2015.
• Barber F. Cold Chain Failure Experience with State Vaccines for Children Program. http://www.stchome.com/blog/cold-chain-failure-experience-state-vaccines-children-program/. Accessed March 2015.
• Department of Health and Human Services: Office of the Inspector General. Vaccines for children program: vulnerabilities in vaccine management. http://oig.hhs.gov/oei/reports/oei-04-10-00430.pdf. Accessed March 2015.