- $49 for a new-pet exam with rabies vaccine and heartworm test ($94.56 value)
Vaccines: Microscopic Sheep in Wolves’ Clothing
This deal includes several necessary shots. Follow along for Groupon’s look at how vaccines are made and how they work.
A vaccination is like a mock battle for the body’s immune system. Vaccines are made from altered forms of the same microorganisms that cause diseases such as measles or rabies, and when the doctor injects them, the body quickly learns how to defend itself from the invading virus or bacteria. That way, if it ever encounters the same pathogen in the real world, it will know just what to do to fight the disease off.
This is possible because of how the body manufactures its own weapons, known as antibodies. When a white blood cell recognizes a foreign agent, it custom-tailors a special protein to lock onto the pathogen and neutralize it so it can eventually be flushed out of the body. This kicks a second process into gear: the creation of memory cells, whose sole purpose is to wait around until they need to create those same antibodies again.
Scientists produce these impostor pathogens in several ways. Some are live organisms that have had their reproductive functions handicapped. Others are chemically killed before being introduced into the body, and others still extract only the superficial features of a pathogen such as a protein or sugar that lies on its surface and can trick the body into thinking it’s encountering the entire organism.
If You Don’t Have Smallpox, Thank a Cow
Vaccine comes from the Latin word vacca, meaning “cow.” That etymology encapsulates the history of vaccines. In the late 18th century, English physician Edward Jenner started paying attention to the folk wisdom that milkmaids never got the oft-deadly disease smallpox. He suspected that they were contracting the closely related but milder cowpox, which then granted immunity to both diseases. While similar phenomena had been observed in many different times and places, it was Jenner’s experimentation and standardization that turned vaccines into a cornerstone of preventive medicine.