Describe the different vaccine types, and the advantages and disadvantages of each

Question

What will be an ideal response?

Answer 1

Currently available vaccines are categorized on whether the vaccine agent is active (live) or inactive. Live vaccines contain a microbe that are infectious but not pathogenic, a condition known as attenuated. Live attenuated vaccines stimulate potent immunological responses, long-lived memory, and activation of B and T cells against multiple antigens. Live vaccine agents may rarely mutate to a more virulent form, posing risks to immunocompromised persons especially. These vaccines may have the potential to transmit other agents from the tissue cultures in which they are grown, and may also transmit from the vaccinated individuals to unwitting contacts. Live attenuated vaccines must be refrigerated up until the time of use.
Inactivated vaccines may contain whole inactivated pathogens, parts of pathogens, or inactivated toxins. These vaccines pose no risk of infectivity to immunocompromised individuals, but they are cleared quickly from the body, so multiple doses are needed for full immunity to develop and be maintained. Whole-agent inactivated vaccines contain the entire pathogen which has been treated with heat, chemicals, or radiation. Subunit vaccines contain select purified antigens from the pathogen, and may be harvest from the pathogen itself or manufactured using recombinant DNA technologies. Toxoid vaccines contain inactivated toxins so that the protection is to the bacterial toxin and not the bacteria itself. Conjugate vaccines contain polysaccharide antigens such as bacteria capsules. Because polysaccharides are poorly immunogenic on their own, these molecules are conjugated to more immunogenic protein molecules. A third category of vaccines based on DNA technologies include DNA vaccines and recombinant vector vaccines. These vaccines introduce pathogen DNA into selected host cells. The genes are transcribed and translated in the patient's own cells, and when secreted or displayed on the cell surface, stimulate an immune response. These vaccines are currently in the experimental stage.