Table 1.

Summary of the characteristics of each vaccine platform.

Platform	Advantages	Disadvantages
Live-attenuated	•Elicit strong immune response •Highly established •Long-lasting protection •Do not need adjuvants	•Requires dedicated biosafety •Risk of regaining virulence •Causes reactogenicity
Inactivated	•Elicit strong immune response •Highly established •Less reactogenicity than live-attenuated	•Lower immune response than live-attenuated •Needs adjuvants
Viral-vectors	•Precise immune response •Safer than live-attenuated and inactivated vaccines	•Variable immunogenicity •Can be influenced by preexisting vector antibodies •Risk of genomic integration
Protein-based	•No biosafety concerns •Strong antibody immunogenicity •Precedent of successful vaccines •Can be formulated into virus-like particles	•Needs adjuvants •May not carry glycans similar to the viral proteins
DNA	•No biosafety concerns •Elicit reasonable immune response •Long-term stability •Can be multivalent	•Variable immunogenicity •Risk of genomic integration
RNA	•No biosafety concerns •No risk of genomic integration •Elicit strong immune response •Can be multivalent	•Possible inflammatory reaction •May require ultra-cold storage •Require delivery by lipid nanoparticles
Trained immunity-based	•Can boost the innate immune response •Already available	•Efficacy and mechanisms still not well understood •No induction of adaptive immunity memory •Reversible and short-durable