- We may have a Covid-19 vaccine by this year itself, with about eight candidates nearing the end of late-stage clinical trials, but getting the shots delivered safely to different countries and then finally to hospitals and pharmacies is set to be the next challenge.
- Since different Covid-19 vaccines require different temperatures and different handling procedures, cold chain facilities, including equipment and procedures used in transport and storage, are a critical aspect before they are eventually administered to the masses. For example, some of the vaccines undergoing phase III trials now must be stored at temperatures as cold as minus 94 degrees Celsius.
What is a cold chain?
- According to the World Health Organisation (WHO), ‘cold chain’ is a system of storing and transporting vaccines at recommended temperatures from the point of manufacture to the point of use. Thus, a cold chain involves three major components of infrastructure: planes, trucks and cold storage warehouses.
- Without a proper cold chain facility, vaccines face the risk of being exposed to temperatures outside the recommended range, resulting in reduction of potency and wastage. According to a report by the International Air Transport Association’s Center of Excellence for Independent Validators in Pharmaceutical Logistics, 25 per cent of vaccines are degraded by the time they arrive at their destination while temperature errors cause losses around $34.1 billion annually.
Covid-19 vaccines need to be stored at what temperatures?
- While MMRV (Measles, Mumps, Rubella, and Varicella), Zoster vaccines are stored at temperatures between -58 degrees Fahrenheit and +5 degrees Fahrenheit (-50°C and -15°C), other traditional vaccines like BCG are usually kept between 35°F and 46°F (2°C and 8°C), according to the Centers for Disease Control and Prevention (CDC). However, some of the leading Covid-19 vaccines need to be stored at much colder temperatures.
- Vaccine candidates from Pfizer and Moderna, which has been developed using messenger RNA technology, requires the shots be stored at subzero temperatures. Pfizer’s vaccine candidates, BN1162b2 and BNT162b2, require a storage temperature of minus 94 degrees Fahrenheit. Once thawed, the vials can be refrigerated for just two days.
Why a cold chain is key
- Vaccines are delicate products that can be damaged in excessive heat, light, or cold. A temperature-controlled 'cold' supply chain is crucial to their transport and storage, especially in a vast, hot country like India. In anticipation of the arrival of a vaccine for Covid-19, the government has started to identify additional cold chain storage facilities for the expected enormous volumes that will be needed to inoculate Indians.
- Moderna, which initially stored its vaccine at minus 70 degrees Celsius, now plans to ship the shots at minus 20, the company said. Once thawed, the vaccine can remain refrigerated for a week.
- Johnson & Johnson’s JNJ-78436735 single-shot vaccine is expected to be shipped commercially at standard refrigeration, a spokesman said. AstraZeneca-Oxford’s ChAdOx1 vaccine (also christened AZD1222 and Covishield in India), which will be manufactured in India by Serum Institute, will have to be refrigerated at 2-8 degrees Celsius. Russia’s Sputnik V vaccine stipulates storage at a temperature not higher than –18 degrees Celsius.
What are the issues in storing, distributing Covid-19 vaccines?
- Investments in infrastructure and storage facilities, especially ultracold freezing capabilities, have not gathered at the same pace in which Covid-19 vaccine development is taking place.
- With hospitals expected to be the initial sites where the first vaccines would be administered, several of them lack ultracold freezers since most drugs and vaccines don’t need them. The chickenpox vaccine is one of the few shots that needs to be stored frozen while flu vaccines require only refrigeration.
- According to the Lancet, the world is capable of producing and distributing around 6.4 billion flu vaccines annually currently while experts have predicted that around nine billion Covid-19 vaccines would be produced in 2021. Thus, without robust cold chain facilities, distributing these vaccines, in addition to the regular ones required, would not be possible.
- Vast parts of the world, including most of Central Asia, much of India and southeast Asia, Latin America, except for the largest countries, and all but a tiny corner of Africa lack the refrigeration to administer an effective vaccination program, AP reported. Experts have opined that West African countries that faced the Ebola outbreak during 2014-16 would be better off since vaccines against the virus also require ultracold storage.
- Besides, a number of other components like vials, stoppers, gauze, alcohol swabs, syringes are also required in huge quantities to inoculate the masses. India, which has the capacity to manufacture more than 2 billion units of these vials, is being tapped by international players for supplies.
How are countries ramping up cold chain facilities for Covid-19 vaccines?
- Several logistics companies like US-based United Parcel Service and German logistics company DHL have already started building new storage facilities. According to Bloomberg, UPS is building two freezer farms, each the size of a football field, to house 600 deep-freezers that can each hold 48,000 vials of vaccine at temperatures as low as -80 degrees Celsius in Louisville, Kentucky, and the Netherlands. UPS is also buying some freezers to install in South America, Frankfurt and the UK. Ultracold freezers typically cost anywhere between $10,000 to $15,000.
- DHL opened a new $1.6 million facility in Indianapolis last month. FedEx is also adding freezers, refrigerated trucks, sensors and even thermal blankets. Pfizer, which has signed an agreement with the European Commission to supply 200 million doses of its vaccine, has already activated its supply chain in Belgium.
- Coming to India, the country has more than 27,000 cold chain points of which 750 are located at the district level and above. The rest are located below the district level, according to government data.