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There are two movies I always find myself watching on July 4th: Independence Day and Forrest Gump (yeah, no star wars)

Independence day, not the sequel, is pristine. It hits all the cliches I like without failing. I have nothing to worry about or big questions after the movie. The sequel was so pale in comparison to the follow up my memories deserved. On the other hand, Forrest Gump while simple on the surface left me with a lot of questions. One of them was about jenny's cause of death.

I'm a doctor so let me ramble a little about viruses and exhibit evidence.

TL;DR: No, she died of Hepatitis-C supposedly according to the author. But I say bullshit.

So if you go to sites about it on reddit or quora, internet movie questions, they will tell that she actually didn't die from aids. That Winston Groom the author of the 1986's novel, said in the sequel

It's not specified in the film, but in the sequel book "Gump & Co" the author mentions that Jenny dies from Hepatitis C as a former drug addict in the early 70s. Hepatitis C was an unknown disease until 1989.

I read the 14 chapters of the book. The name Jenny was mentioned 61 times and there was no mention of the cause of death aside from this.

No mention to drug addiction in this book or to the liver or to jaundice or something that would help me figure it out.
So not in the book. Maybe Groom mentioned it somewhere else, but I can't find a source to it.

Here's an interview with Robert Zemeckis, director of the film (one of the most talented guys in the industry), here he responds in 1 minute, about this particular subject on Jenny's death.

The rumors try probably try to hide the fact that at the moment the book was written the author didn't know what the aids implied and after the movie became a symbol of the American culture, people kind of fell ashamed of Jenny. Now we understand as adults a little more the subtleties in the movie.

The text in the movie reads

Jenny: Forrest, I'm sick.

Forrest: What, do you have a cough due to cold?

Jenny: I have some virus, and the doctors, they don't know what it is, and there isn't anything they can do about it.

There are a ton of viruses that could kill someone and weren't identifiable in the early 80's. Hep C wasn't properly categorized until 1989 and until 1992 there was no real treatment for it. It's a silent killer that has at least 170 million people are affected. 2.5% of the world population. It's an epidemic that kills millions, silently, every year. Life expetancy is normally more forgiving and syntomps were more readily available for that disease when compared to HIV. Nonetheless, when most people found out about this the biggest candidate to come is HIV.

The most probable date for the death of Jenny is in 1982. So it falls inside the window of opportunity.

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So yeah, at the time the writer didn't know and used real life examples without knowing the cause. This only made the movie deeper and richer in my opinion. Speculating now is useless, what one can be sure is that at that time consequences for things we take for granted today were quite high. Today we can cure Hep C, and almost cure HIV (clinically, in medical terms). In retrospective is quite sad because is so close to real life and so surreal.