What are vaccines?
Vaccines are products that stimulate the immune system to recognize and fight specific pathogens (like viruses or bacteria) without causing disease. It protects individuals from developing serious or life-threatening illnesses caused by infectious diseases. Hence, protecting communities by reducing the spread of infectious diseases and contributing to herd immunity helps prevent outbreaks.
Why should I get vaccinated?
Getting vaccinated is an important public health measure. It can help save lives, prevent illness, and reduce the burden on healthcare systems.
Types of vaccines
There are several types of vaccines available, including:
- Inactivated or killed vaccines
- Live attenuated vaccines
- Subunit, recombinant, or conjugate vaccines
- Messenger RNA (mRNA) vaccines
- Vector vaccines
Inactivated or killed: contain viruses or bacteria that have been killed or inactivated. They can no longer cause disease. Examples include the vaccines for polio, hepatitis A, and influenza.
Live attenuated: contains weakened viruses or bacteria that are still able to replicate in the body but are not strong enough to cause disease. Examples include measles, mumps, rubella, and chickenpox.
Subunit, recombinant, or conjugate: contains only specific parts or pieces of a virus or bacterium rather than the entire pathogen. Examples are human papillomavirus (HPV), hepatitis B, and Haemophilus influenzae type b (Hib).
mRNA vaccines: use a small piece of genetic material called messenger RNA (mRNA) to instruct cells to produce a harmless piece of the virus or bacteria that can then trigger an immune response. Examples include the COVID-19 vaccines from Pfizer-BioNTech and Moderna.
Vector vaccines: use a weakened or harmless virus to deliver genetic material from the pathogen into the body to stimulate an immune response. Examples include the vaccines for Ebola.
Heard Immunity
Herd immunity, also known as population immunity, is a situation where a large proportion of a population is immune to a specific infectious disease through vaccination or previous exposure to the disease.
When a large enough proportion of the population is immune, the spread of the disease is slowed down or stopped, even among individuals who are not immune.
Hence, this can protect vulnerable individuals or those who are at higher risk of severe illness or complications. The exact threshold for herd immunity varies depending on the infectious disease, but it generally requires a high level of vaccination coverage or previous exposure to the disease in a population.