From the 16th century till 1940, whooping cough victims were, at maximum, 200,000 people per year. About 8,000 people died each year, now about 20 as of August 2015.

Anatomy: a bacteria in the respiratory system that hooks to the cell lining of the throat. Bacteria moves to ciliated cells of the lungs. Pneumonia may develop if tiny air sacs deep in lungs become infected. Lungs become a fanning device for the toxins and spreads them through the whole body. Bacteria releases a toxin that kills the cilia and cells.

Physiology: Cough that can be chronic or severe. Nasal congestion, runny nose, or sneezing. An overall tiredness and fever may occur. Other symptoms are paroxysmal cough, episodes of no breathing, vomiting, or watery eyes.

B cells on their own is not enough to take down the disease alone. They need the induction of interferon (IFN)-y-secreting T helper type 1 cells. Targeting B memory cells is what scientists have decided to do in order to keep the bacteria from ever returning.

The vaccine is filled with an inactivated version of the virus. Multiple doses are required for complete immunity against the virus.