How are vaccines made?
Usually, companies independently work to complete the clinical development plans for a vaccine. Following its authorisation, manufacturing begins to scale up. The process involves weakening or deactivating the antigen (that part of the pathogen that causes an immune response), and then all the ingredients are combined – creating the full vaccine.
Usually, this process can take over a decade from the preclinical trial to the manufacturing. However, this can be sped up, using protocols that are put into place when there is an emergency health crisis that has a global impact. This is called the Emergency Use Listing Procedure. This process can be sped up even more when countries work together with international health organisations.
Packaging of vaccines
Following the creation of vaccines in bulk numbers, it is bottled in glass vials and then carefully packaged for safe cold storage and transport. This packaging needs to be able to resistant to extreme temperatures, as well as being able to withstand the logistics of be transported around the world. As such, they are usually made out of glass – as this material is durable and can withstand extreme temperatures while keeping its integrity.
Storage of vaccines
Vaccines are sensitive to temperature changes. They can become ineffective or even inactive if exposed to temperatures that are too hot or too cold. Because of this, they are very sensitive to the storage used for them. As such, special medicalised refrigerators are needed for these products, as regular refrigerators cannot maintain an even temperature consistently and tend to fluctuate too drastically for vaccines. Some vaccines require storage in exceptionally cold temperatures, such as -70°C (-94°F). Others require temperatures as cold as -20°C (-4°F), while most need refrigerated storage temperatures between 2°C and 8°C (35.6°F to 46.4°F). Some frozen vaccines can also be stored safely – but for a limited time period – between 2°C and 8°C (35.6°F to 46.4°F).
How vaccines are shipped
To keep the coolness consistent throughout shipping, vaccines use specialised equipment so that the product is not damaged in any way, including being exposed to the incorrect temperatures. Lorries that are refrigerated transport the vaccines to the warehouse where they are to be stored, following the vaccines being transported to the airport. From the warehouse, the vaccines then go into portable iceboxes to transport them to the regional centers where they are needed, and are stored there in refrigerators. Should a vaccination happen outside of one of the regional centers, sometimes portable iceboxes are used to transport them. Technological advances which allow devices to be transported at cold temperatures for several days without the need to be attached to electricity have been developed.
Quality Control of Vaccines
Following the administration of vaccines, the authorities and the World Health Organisation (WHO) monitor for any adverse side-effects or irregular responses for people who have recieved the vaccine. What is most important is the safety of the recipients of the vaccine.
In light of this, regular testing and studies take place to report on the effectiveness and safety. Furthermore, often studies take place to determine the length of the protective nature of the vaccine.