Cold Chain Transport for Vaccines 

Effective and secure transport arrangements should be in place for moving vaccines keeping the correct temperatures. The process can be defined in 5 steps: 

1. Assessing the shipment conditions.
2. Deciding the suitable means for vaccine transportation.
3. Preparing the shipment.
4. Shipping.
5. Reception and Cold chain verification.

When opening new distribution channels or recurrent cold chain breaks are experienced in current distribution, qualifying transport routes is recommended. The process typically involves monitoring worst-case routes in order to ensure that the personnel and the chosen equipment and packaging arrangements are able to maintain acceptable transport temperatures even in such cases.  

1.Assessing Shipping Conditions  

Assessing the shipment conditions encompasses: 

• Calculating the volume of vaccine to be shipped.
• Evaluating the journey circumstances.

Calculating Volumes 

To calculate the volume of vaccine to be shipped, it is necessary to know for each vaccine and diluent in the shipment: 

• The required storage temperature: 4 ranges of temperature are normally considered for vaccine transportation:-80 to -60ºC,  -15 to -25°C, +2 to +8°C or ambient;
• The number of doses to be transported;
• The packed volume per dose (cm3/dose). The packed volume includes the vaccine vial, the packet containing the vaccine vial and any intermediate packaging (secondary packaging).

The maximum recommended packed volume per vaccine dose and diluent are: 

See attachment 1: A1_Log_Cluster_The maximum recommended packed volume per vaccine.docx 

Be aware that the volume obtained from multiplying the packed volume per dose by the number of doses only takes into consideration the primary and the secondary packages: it doesn’t include the cold box packaging. Estimating the final transport volume (including the cold box) is necessary to correctly plan the transport means. For this purpose, a transport box bulking factor can be used. The bulking factor depends on the type of vaccine. WHO Guideline for establishing or improving primary and intermediate vaccine stores, recommends the following transport box bulking factors: 

• BCF, OPV, measles, MMR, MR = 6.0
• Other vaccines = 3.0
• Diluent, droppers = 1.5

2.Evaluating the Journey  

To evaluate the journey, some of the criteria to be considered are: 

• Transport modes and vehicle types.
• The journey distances and their expected duration.
• The environmental conditions: temperature (day-night and seasonal temperature extremes) and geographical and natural hazards.

There are 3 basic transportation stages in the supply chain of vaccines: 

1. From the manufacturer to a primary or central store: usually international shipments.
2. Between (intermediary) stores: normally between national or district store facilities and down to the Distribution Site.
3. Outreach transportation: final vaccine delivery during regular EPI or to a vaccination site during a mass vaccination campaign.

Aerial or terrestrial modes are preferred for vaccine transportation. Air transport is usually chosen for international or long-distance shipments. Terrestrial is used for transport of vaccine within the same country. Outreach is often done by any land transport mode: car, motorcycle, bicycle. Because of the long duration of the journeys, vaccines are rarely transported through water-borne means. 

For further information on how to design a vaccine distribution system, refer to:  

Attachment 2 WHO Guideline for establishing or improving primary and intermediate vaccine stores. 

TYPES OF TRANSPORT 

Suitable Containers for Vaccine Transportation 

There are several alternatives for the shipment of temperature-sensitive cargo: 

Refrigerated (Multimodal) Containers 

A refrigerated (multimodal) container or reefer, is a shipping container equipped with an integrated refrigeration unit for the transportation of temperature-sensitive cargo. They rely on external electrical power provided from the ship, the quay or the trailer. This type of containers is suitable for large-scale shipments and when the journey requires changing modes of transport (i.e. road-sea-road). Normally over long distances. 

This type of shipment is rarely used for vaccine transport. For long distances or inter-continental movements, vaccines are commonly air-shipped in cold storage containers, which are either actively powered or passively kept cold. Therefore, refrigerated multimodal containers are not advised for the transportation of vaccines. 

Air cargo of vaccines 

International transport of vaccines is regulated by IATA. It is recommended to engage a professional freight forwarder agency to organise the international transport of vaccines. 

Please refer to: 

Attachment 3:IATA Guidance for Vaccine and Pharmaceutical Logistics and Distribution. Edition 3, February 2021 

Refrigerated Vehicles 

A refrigerated vehicle is a van or truck with a thermally isolated cargo compartment, equipped with a mechanical refrigeration system for road freight transport at specific temperatures. 

Such vehicles are utilized for large-scale transport of vaccines from the manufacturer to primary/central stores and in certain context for bulk transport between primary/central stores and secondary stores. Refrigerated vehicles are commonly run by specialized logistics operators. 

Still, the high cost of refrigerated vehicles and their tendency to suffer mechanical breakdowns, have prevented many developing countries from using this transport method for regular deliveries. Additionally, when using a refrigerated vehicle in such contexts, it is recommended cold packing provisions to protect vaccines in case of a vehicle breakdown. 

Given that some cold boxes, if properly loaded, have enough cold life to cover transportation needs at the national level, the use of refrigerated vehicles for bulk transport of vaccines is also discouraged if the reliable infrastructure is not accessible. 

Different types of road transport for cold chain 

• Isothermal carrier. It has a cabin equipped with insulating walls, including floor, doors and roof. Thanks to this, the heat exchange between the interior and the exterior is considerably reduced.
• Cold carrier. It has cooling technology that allows the interior temperature to be reduced and always maintained within a range of 12 to -20 °C, depending on the type of vehicle used.
• Refrigerated carrier. It is a type of vehicle that helps to reduce the temperature inside the passenger compartment and to maintain it for an average outside temperature of between 30 and -20 °C.

Points to consider :

• A number of operational problems arise from the use of refrigerated vehicles for the bulk transport of vaccines. Their use can therefore be justified only for very large programmes in countries with a population of more than 75 million. For smaller programmes, and even in a large country, transport using non-refrigerated vehicles and cold boxes is considered to be safer and more practical. ·
• A programme that depends on one or a small number of refrigerated vehicles may be seriously hampered if a vehicle breaks down. Make sure that you have alternative transport.
• · Some cold boxes have enough cold life for the needs of most mobile or outreach facilities.
• · Before you select a refrigerated vehicle for use in the EPI, consult local standardization policies and investigate local servicing facilities. In order to ensure that an appropriate unit is selected, include in the specifications for the supplier the ambient temperature of the region in which the vehicle will operate, and the temperature requirements of the refrigerated compartment. For cooling units that operate from a mains electricity supply while the vehicle is stationary, also give details of the mains voltage, number of cycles and the phase–pole connections.

Types of cooling unit  

Refrigerated vehicles usually have a cab for the driver, a chassis fitted with a separate insulated box-type body and a cooling unit. The following types of cooling unit are used:  

• Fitted cooling unit This is a cooling unit fitted to the engine of the vehicle. It has the following disadvantages:
  • There is no cooling for the vaccines when the engine is not running;
  • The cooling unit takes considerable power from the engine with the result that the vehicle is less powerful and is difficult to drive over rough or mountainous terrain.
• Separate cooling unit This type of cooling unit is fitted to the truck body and has either a petrol or a diesel motor. It has the following advantage:
  • A larger quantity of vaccines can be transported.
  • It has the following disadvantages:
  • Prices vary greatly and are subject to special quotation.
  • Specialist engineers are required for this type of unit so it is important to ensure that maintenance facilities are available for both the vehicle and the cooling unit.
• Important: The fuel required for the cooling unit should be the same as the fuel required for the vehicle engine.
• Mounted refrigerator A refrigerator mounted in the back of a standard vehicle offers little or no advantage over a normal cold box placed in that vehicle and it has the following disadvantages:
  • The refrigerating and icepack-freezing capacity of the few models that fit into a standard vehicle are negligible once the vehicle is in motion.
  • ·Unless the vehicle is fitted with a split-charge facility and two batteries, the refrigerator will run the vehicle battery flat in about 8 hours.
  • ·A vehicle with a refrigerator mounted inside it becomes a special EPI vehicle that cannot be used for other primary health care activities.
• Important If no cold box with a sufficient cold life is available, a more reliable solution than to mount a refrigerator in a vehicle is to ensure the availability of freezing capacity along the way (install a fr