The ‘cold chain’ is the system of transporting and storing vaccine at +2oC to +8oC from the place of manufacture to the point of vaccine administration (the individual).
The success of an immunisation programme depends on the cold chain to maintain vaccine potency. To achieve this, the recommended temperature of +2oC to +8oC must be maintained during storage and distribution at all times to avoid irreversible loss of potency from thermal insult (heat or freezing). All immunisation providers who store or transport vaccines should maintain their vaccine refrigerators as close as possible to +5oC, which gives a safety margin of plus or minus 3oC.
The integrity of the cold chain is dependent not only on the equipment used, but also on the people involved and the practices they undertake.
The distribution of the funded vaccines throughout New Zealand is through a direct delivery system, which reduces the potential for vaccine damage to occur (see section A6.5 for information about the National Cold Chain Audit). Vaccines are distributed by courier, in appropriate insulation, and delivery and unpacking must occur within the predetermined ‘window’ period (see section A6.2.4).
In the event of any sudden variations in refrigerator temperature, or recordings outside the recommended +2oC to +8oC range, or equipment failure, the immunisation coordinator, medical ofﬁcer of health, public health service or the regional immunisation advisor should be contacted for advice and support.
All immunisation providers should have easy access to the current Immunisation Handbook, and to the National Guidelines for Vaccine Storage and Distribution and the Annual Cold Chain Management Guide and Record (available at www.health.govt.nz/coldchain). These are essential documents to ensure the vaccines delivered within New Zealand have been stored correctly to maximise their effectiveness.
Cold chain accreditation (CCA) is a tool to support an immunisation provider’s cold chain management practices. Immunisation providers demonstrate their cold chain management through self-assessment, followed by a review by an approved CCA reviewer (eg, immunisation coordinator or approved assessor) to confirm all requirements have been achieved.
CCA is valid for up to three years, based on the reviewer’s findings. All immunisation providers who store vaccines and/or offer immunisation services must achieve CCA, including (but not limited to) general practices, public health units, community pharmacies, travel clinics, occupational health clinics, emergency medical services, research units and hospital wards/clinics/departments/pharmacies.
Completing this process will enable immunisation providers to meet the cold chain Aiming for Excellence indicator 17 of the Royal New Zealand College of General Practitioners (RNZCGP) Cornerstone Programme.
CCA is based on the following ﬁve assessment sections:
A CCA review measures performance against the criteria as follows:
If the CCA requirements are not met, a remedial plan is put in place while the provider meets the CCA requirements. The provider is still able to administer vaccines while this remedial plan is being achieved if the recommended temperature range can be maintained at all times. Failure to take remedial action to meet the requirements by the time of the repeat review/assessment may lead to the vaccine supply being temporarily suspended.
For a practice to achieve CCA, it must meet all the requirements for cold chain management. Refer to the CCA Provider Self-Assessment and CCA Immunisation Provider Review forms available on the Cold Chain pages of the Ministry of Health website (www.health.govt.nz/coldchain).
Each immunisation provider should have an individualised and documented cold chain management policy. This should include details of the designated cold chain management staff member, vaccine stock requirements, vaccine ordering and storage processes, vaccine disposal, refrigerator operation, and maintenance and management processes, along with an emergency procedure for dealing with equipment and power failures.
The cold chain management policy should be dated and signed by the relevant staff and reviewed on an annual basis. A cold chain management policy template, which covers all the areas of cold chain management required to achieve CCA, is available on the cold chain pages of the Ministry of Health website (www.health.govt.nz/coldchain).
All vaccines must be stored at the recommended temperature range, but there are other specific requirements in the Medicines Act 1981 and Regulations for the storage and handling of vaccines.
Part 5 of the Medicines Regulations 1984 sets out legal requirements in relation to the packaging, storage and handling of medicines in general. Section 47 of the Medicines Act 1981 sets out some speciﬁc requirements relating to the storage and delivery of prescription and restricted medicines, including vaccines.
The Medicines Act 1981, section 47, Storage and delivery of medicines states:
The refrigerator should be of sufﬁcient size to accommodate vaccine storage requirements without exceeding the manufacturer’s recommendations for maximum storage capacity. Contact the local immunisation coordinator for advice before purchasing new cold chain equipment.
The refrigerator should have an independent power point and a plug-in surge protection unit. The plug should be taped over (with a written warning against unplugging) to overcome the risk of disconnection. An alternative may be to permanently wire the refrigerator into the outlet.
The refrigerator must be in a reasonably sized, well-ventilated room and not in direct sunlight or against a heat source/external wall, because the efﬁciency of refrigeration equipment declines with high ambient temperatures. There should be sufﬁcient ventilation around the condenser of the refrigerator (the recommendations are at 7.5 cm from the refrigerator’s back and sides) to allow air to circulate, because this will help to reduce cyclical ﬂuctuations. Contact the manufacturer of a pharmaceutical refrigerator before moving the refrigerator.
The following actions should be taken to ensure the efﬁcient refrigeration of vaccines.
|Record the refrigerator temperature in the temperature log/register. |
Ensure the top of the refrigerator remains clear (except for the temperature log/register).
|Review the temperature log/register for any cyclical fluctuations and climatic changes. Check the back plate inside the refrigerator for any visible ice.|
|Check that the door seal grips the door all around the frame; that there are no large air gaps that will affect the efficiency of the fridge; that there are no large splits or cuts in the seal that will affect hygiene; and that the seal is clean and free from mould and debris. |
Leave the door open to perform the self-closing door check. The door should close automatically. To ensure this, alter the height adjusters underneath the refrigerator so that the door hinge side of the refrigerator is set slightly higher than the non-hinge side.
All interior and exterior surfaces of the refrigerator should be cleaned at least every six months with a solution of 0.03 percent hypochlorite solution (1 part domestic bleach to 99 parts water).
|Annual independent validation of the refrigerator’s temperature is undertaken by the local immunisation coordinator. Contact the immunisation coordinator for more information. |
Service the refrigerator annually, according to the manufacturer’s instructions or if the temperature ﬂuctuates.
|During power failures|
|During a power failure the refrigerator door should be left closed. |
If the power fails for more than four hours, vaccines should be transferred to an appropriately sized insulated vaccine container with the correct number and size of ice packs to ensure the vaccines will remain at +2oC to +8oC. A minimum/maximum thermometer will assist with temperature monitoring.
If the power is not restored, the vaccines will need to be transferred to an alternative refrigerator that has a power supply, as outlined in your cold chain policy (see the information on vaccine transportation in section A6.3).
Each refrigerator storing vaccines must have an electronic temperature-recording device (eg, a data logger) that measures the current temperature and the minimum and maximum temperatures reached since the device was last reset. The device should be able to record and download data from the previous month.
The temperature should be read and recorded daily, preferably at the same time each day. These recordings should be reviewed every four weeks and compared with monthly data logger recordings to identify cyclical ﬂuctuations and climatic changes. The immunisation coordinator may be able to assist with further information on refrigerator temperature recording devices.
Once CCA has been achieved, six-monthly/annual electronic monitoring can also be undertaken by the PHO or the practice’s refrigerator temperature recording device. Temperature records need to be retained for a minimum of 10 years.
All immunisation providers should have a system for recording vaccine stock levels (ie, a stock management plan). The plan should include vaccine requirements, ordering, stock rotation, and the use of a log/register to document the date, name and batch numbers of vaccines arriving from the supplier, vaccine expiry dates and date of receipt.
When a vaccine delivery arrives, the vaccinator or workplace should check the cardboard box or chilly bin contents against the order form. Check that the vaccine delivery is within the stated delivery window. Once satisﬁed with the vaccine order, the vaccinator or receptionist should sign for the vaccines. If the cardboard box or chilly bin has a yellow sticker, see section A6.5 for information about the National Cold Chain Audit.
If the vaccinator has reason to believe the vaccines have not been kept at the required temperature, they should notify the supplier and contact their local immunisation coordinator for advice and, if necessary, return the vaccines.
Immunisation providers also need to consider whether there may have been multiple breaches of the cold chain. This means that all breaches should be managed on an event and/or batch-by-batch basis. There may also be situations where a breach is not identified until some time later (ie, retrospectively). It is important to note that thermal damage to vaccines is cumulative.
Table A6.2 below provides general guidelines to help guide action in specific situations. The immunisation coordinator will consult with the vaccine manufacturer because they may have additional information on the thermostability of the vaccine. The manufacturer will advise the coordinator on a batch-by-batch basis whether the vaccine can be used and within what timeframe.
|Vaccine||Protect from light||Exposed to temperatures below 0oC||Exposed to temperatures between 8oC and 25oC|
|BCG||Yes||Use||Contact the immunisation coordinator with details of vaccine batch number, maximum temperature reached and duration of exposure to determine if the vaccine is suitable for use.|
|Diluent||No||Do not use*|
|DTaP-IPV-HepB/Hib||Yes||Do not use*||Contact the immunisation coordinator with details of vaccine batch number, maximum temperature reached and duration of exposure to determine if the vaccine is suitable for use.|
|Hib pellet in the above||No||Use|
|DTaP-IPV, Tdap||No||Do not use*||Contact the immunisation coordinator with details of vaccine batch number, maximum temperature reached and duration of exposure to determine if the vaccine is suitable for use.|
|Diluent||No||Do not use*||Use.|
|Hepatitis A||No||Do not use*||Contact the immunisation coordinator with details of vaccine batch number, maximum temperature reached and duration of exposure details to determine if the vaccine is suitable for use.|
|Hepatitis B||No||Do not use*||<5 days: Use. |
≥5 days: Do not use.*
|HPV4||Yes||Do not use*||<72 hours: Use. |
≥72 hours: Do not use.*
|Do not use*||Contact the immunisation coordinator with details of vaccine batch number, maximum temperature reached and duration of exposure details to determine if the vaccine is suitable for use.|
|IPV||No||Do not use*||Contact the immunisation coordinator with details of vaccine batch number, maximum temperature reached and duration of exposure details to determine if the vaccine is suitable for use.|
|MCV4-D||Yes||Do not use*|
|MenCCV||No||Do not use*|
|Diluent||No||Do not use*||Use.|
|PCV10||Yes||Do not use*|
|PCV13||No||Do not use*|
|23PPV||No||Do not use*|
|RV5||Yes||Do not use*|
|Td||Yes||Do not use*||<5 days: Use. |
≥5 days: Do not use.*
|Varicella||Yes||Do not use*|
|Diluent||Yes||Do not use*|
When transporting vaccines the temperature must be maintained between +2oC and +8oC at all times. Therefore, immunisation providers must use insulated containers (designated transport containers or polystyrene containers) when transporting vaccines (eg, for a school immunisation programme) or if there is a power or equipment failure. A temperature monitoring device (eg, data logger) should be placed with the vaccines during this time.
Ice packs must be frozen at least two days before being used for transporting vaccines. When placing ice packs in the freezer, set them on their edge and allow space between them to ensure even freezing. Table A6.3 below describes the process for preparing vaccines for transport.
|Use only proven methods for transporting vaccines, such as an insulated vaccine container* (solid-wall transport containers, double-walled transport containers and polystyrene containers) with a clip-on lid.|
|Use a vaccine container of a size suitable for the amount of vaccine to be transported.|
|Use the appropriate number and size of ice packs for the vaccine container size, to ensure the vaccines will remain at +2oC to +8oC throughout their journey.|
|Monitor the vaccine container with an electronic temperature-monitoring device at all times (eg, a data logger).|
|Before placing the ice packs in the vaccine container, warm them until frost no longer forms on their surface.|
|Place approved* insulation material in the bottom of the vaccine container, then place the vaccines so that the most heat sensitive are nearest the ice packs and the most freeze sensitive are furthest away from the ice packs.|
|Separate the ice packs from the vaccine with the approved insulation material. This will prevent contact with the ice packs and thus ensure they will not freeze the vaccines.|
|Secure the lid in place using the clips, or, if not present, adhesive tape.|
Following these recommendations will keep the temperature within +2oC to +8oC for up to ﬁve hours and allows for the vaccine container to be opened brieﬂy, up to four times.
In a school-based immunisation programme, when vaccines are likely to be stored in containers for longer periods and more frequent opening will occur, extra care must be taken with cold chain maintenance. To keep the temperature between +2oC and +8oC, an extra insulated container of frozen slicker pads or Environfreeze should be carried and added to the vaccine container as needed for temperature control.
When multiple vaccine containers are required, use one at a time – use all of the vaccines from one container before opening and using the next container.
Vaccines for destruction must be correctly disposed of, as required under the Resource Management Act 1991.
Immunisation providers should contact the local immunisation coordinator before disposing of vaccines. Unwanted, discontinued or expired vaccines and/or those subject to a cold chain failure should be prepared as follows and returned to the supplier.
For advice on the return of non-Schedule vaccines, contact the supplier directly.
PHARMAC and the Ministry of Health commission the National Cold Chain Audit to monitor Schedule vaccines. The audit monitors the cold chain of vaccines from their origin at the National Vaccine Store until immunisation providers have administered all doses in the vaccine pack/box.
More information on the National Cold Chain Audit is available at www.health.govt.nz/coldchain.