Hacking our body’s immune system is very easy. Employ medicines to snatch body’s fundamental rights and observe. Immunity will be compromised.
For example:
1) Antipyretics drugs oppress body’s right to maintain right temperature.
2) Antibiotics deny the body’s right to do communication with microbes.
Even basic drugs like above abort body’s freedom of self-healing.
PS: I do not deny positive role of medicines in extreme critical conditions. But that is just 0.1% of current usage of medicines. 99.99%, it is misuse.
Or, make humans addict of something (From smoking to reading to work!). Immunity will be compromised.
Beware of hackers! 
🙂 Strengthen your firewall. Preventive care is the only cure. Regular routine, exercise, good sound sleep, healthy diet, pure water, enough sunrays, play, socializing with families and friend, time spent in nature! Enough preventive care!
