As Bacteria, Start Anywhere You Want (I Picked China) On Casual Difficulty.
Save Up Points Until You Can Evolve All These At The Same Time:
- Livestock 1 And 2
- Nausea
- Vomiting
- Diarrhoea
- Coughing
- Pneumonia
- Sneezing
- Insomnia
Wait A While Afterwards And The Achievement Will Pop.
Good Luck!