There are vaccines against many of them (smallpox etc.), but the development of one for AIDS just hit the wall. I am not a doctor or researcher, but IIRC, that particular virus mutates rapidly.
There are anti-viral treatments that reduce an already-infected individual's viral load. The treatments are currently expensive and of limited effectiveness, but progress is being made.
Viruses are easy to kill outside of the body. It's when they get inside that they're hard to kill without killing everything else around them.
A vaccine works by predisposing the immune system to recognize the invading virus and yank it out of the system before it multiplies. The classic example is polio.
The problem with HIV, and flu (though different families of viruses) is that they change their coat so frequently that the immune system can't keep up. Like some generals, it's always prepared to fight the last war. The flu virus changes in somewhat predictable ways so that a new vaccine can be prepared each year to at least offer some protection against the "new look" for that cycle. HIV is unpredictable at present.
While we haven’t totally done away with polio, I believe that the vaccine has done wonders to stop it in Western civilization.
Smallpox.
Smallpox was eradicated and, last I read, exists only in research facilities and biological weapons storage. Polio has not been wiped out, but clearly decimated.
Polio is or was nearly dead. But it was killed by "starvation". The vaccine prevents one from getting, and also from spreading, the disease.
However, unlike antibiotics used against bacteria, a vaccine doesn't kill the infection, a virus in this case, if you've already gotten it.