Answer:
Virus
Explanation:
Viruses are even smaller than bacteria and require living hosts — such as people, plants or animals — to multiply. Otherwise, they can't survive. When a virus enters your body, it invades some of your cells and takes over the cell machinery, redirecting it to produce the virus.
Mood swings, bad thoughts
<span>Some of the factors that influence emotional changes throughout adolescence are: increased sensitivity to criticism, change in self perception, change in the manner in which adolescent are treated, increased desire for independent living, increased desire for social acceptablility, crisis with self-confidence, etc.</span>
Sounds like Sergio might be suffering from a fungal infection.
