CEPI’s mission to accelerate vaccine development against infectious diseases is underpinned by an approach that explores the potential for a range of different vaccine technologies, all or any of which might be tailored to respond quickly and effectively to a future epidemic or pandemic threat.
By investing in research and development for multiple types of vaccine platform, such as viral vector, protein subunit and mRNA technologies, CEPI mitigates against the risk of relying on a single technology. This increases the likelihood of successfully developing safe and effective vaccines for both known epidemic threats and future novel ‘Disease X’ threats.
Using ‘Answer the Public’, we analysed some of the most popular search terms related to protein subunit vaccines across the United States, Australia and Singapore, which were among the top countries searching ‘protein subunit’ over the past 12 months, according to Google Trends at the time of publishing.
A selection of those questions, with CEPI’s answers, is below:
What is a protein subunit vaccine?
A protein subunit vaccine uses fragments of a disease-causing pathogen to teach the body’s immune system how to recognise and defend against it. Rather than injecting a whole pathogen to prompt an immune response, subunit vaccines contain purified, harmless pieces of it that have been specifically selected for their ability to trigger a response in immune cells without causing a disease.
How do protein subunit vaccines work?
Protein subunit vaccines teach the immune system to mount a protective response against a key protein on the surface of a pathogen. The proteins selected for the vaccine to target are ones that the pathogen uses to cause disease—so by inducing an immune response against them the protein subunit vaccine helps the body to fight against the infection.
Are protein subunit vaccines safe?
Protein subunit vaccines are considered to be very safe, because they have no live components and use only purified fragments of the pathogen. Regulator-approved protein subunit vaccines have been used successfully for decades to protect millions of people from diseases such as hepatitis B.
Can protein subunit vaccines have side effects?
All vaccines and medicines can have side effects, but serious side effects are extremely rare and far outweighed by the risks of the diseases they are designed to protect against.
With protein subunit vaccines, the already low risk of side effects is further minimised by the fact that they use only tiny pieces of the pathogen, rather than the whole virus or bacteria. This feature also means that protein subunit vaccines are more stable than vaccines that contain whole viruses or bacteria.
What are the advantages and disadvantages of protein subunit vaccines?
Stability and a low risk of side effects are two of the main advantages of protein subunit vaccines. Because they contain no live components, they are also particularly suitable for pregnant women and people with compromised or weakened immune systems, such as elderly people or people living with HIV.
However, protein subunit vaccines may not induce as strong or long-lasting immunity as some other types of vaccines, such as mRNA or viral vector vaccines, and may need to be boosted with additional doses to give better protection. To enhance the immune response, some protein subunit vaccines are combined with an adjuvant—a substance that boosts the vaccine's effectiveness.
Viral vector vaccines – What they are, and what they are not
mRNA vaccines – What they are, and what they are not
