ILL BEHAVIOUR

The internal sickness showdown goes a little something like this

DAY 1

An invader enters your body. Maybe a virus gets in through a cut in your skin, or harmful bacteria passes from your SO’S mouth when you go in for a kiss. Your immune system recognises it as an intruder and, within minutes, gets to work to start fighting it.

DAYS 3-4

When symptoms hit, it’s a sign that the inflammatory response is in motion. This process may include raising your body temperature (hello, fever), because most viruses and bacteria have evolved to replicate at 37°C. This will slow their ability to multiply. It also helps send signals to white blood cells that they need to act.

DAYS 5-8

If the enemy is mild and you can overpower it, your white blood cells will detect that the job is done and retreat, and the inflammatory activity turns off. You’ll start to feel like yourself again. But if you still feel rotten after several days, your lymph nodes ramp up the production of T cells and B cells to continue the fight.

THE FINALE

After all is said and done, your immune system keeps some of the cells that target that particular infection stored in your immunological memory, allowing your system to quickly remember an antigen it had a run-in with in the past. Every time you’re exposed to a disease or you get a vaccine, your body stashes B cells, which make an appropriate antibody, so you’re better able to spar with the infection if you’re exposed to it again. Immunity science: pretty mind-blowing stuff.