Final answer:
The statement that vaccination may involve being injected with a viable virus is true for live attenuated vaccines, which contain weakened viruses, and false for killed or inactivated vaccines, which contain no viable viruses. Vaccines activate the immune system and create memory cells, preparing the body to fight the actual pathogen without causing disease.
Step-by-step explanation:
True or False: Vaccination may involve being injected with a viable virus. This statement is both true and false, depending on the type of vaccine in question. Vaccines are a critical tool for preventing viral infections and can be made from either live weakened viruses, killed or inactivated viruses, or molecular subunits of the viruses.
Vaccines work by stimulating the immune system to produce an immune response. This response involves the creation of memory cells that will recognize and fight off the specific pathogen if encountered in the future. Vaccines using live attenuated viruses are known to induce a strong and long-lasting immune response, but they carry a very small risk of causing the disease they aim to prevent. This type of vaccine may be said to involve the injection of a “viable” or living virus, albeit a weakened version that typically does not cause disease in healthy individuals.
In contrast, vaccines composed of killed or inactivated viruses do not contain viable (living) viruses capable of causing disease. These types of vaccines include those that have used parts of the virus like proteins or genetically engineered segments to create an immune response. While they generally lead to less potent or shorter-lived immunity compared to live vaccines, they have no risk of causing the disease.
An example of a live attenuated vaccine is the one used against measles, mumps, and rubella (MMR), while examples of killed vaccines are the influenza and hepatitis A vaccines. The method by which a vaccine operates has evolved, with modern techniques involving specific genes and recombinant DNA technology to generate targeted immune responses.