What does the woman from the future mean when she says she's "in insurance"?

She is "insurance" that the virus will successfully be spread around the world.

The key is that the scientists were never interested in stopping the virus in 1995. As Cole says early on, "I just have to locate the virus in its original form before it mutates. So scientists can come back and study it and find a cure. So that those of us who survived can go back to the surface of the earth."

But later Cole decides to stay in 1995, and by the airport scene, he has given the future scientists the slip by cutting out his teeth. Except Cole leaves a message from the airport, leading the future scientists back to him -- with a two-part plan:

1. Cole's message did not identify the virus spreader, so Jose's task at airport is to give Cole the gun and then watch who Cole goes after. When Catherine runs up and says she's figured out it is the redhead assistant to Dr Goynes who spreads the virus, Jose fades out of the scene, having got what he needed. (for confirmation see scene as written in production draft of script)

2. From there, the scientists need to make sure Cole does not actually prevent the virus from being spread because that would dramatically disrupt the timeline. To prevent the disruption, the lady scientist is sent as back-up who -- if Cole somehow manages to stop redhead-ponytail guy -- can grab the briefcase, take the flights, and make sure the virus still gets spread around the world (which seems to end up being unnecessary because redhead-ponytail gets on plane OK)

Luckily for the scientists, airport security shoots Cole when Cole tries to shoot the redhead guy. (The scientists may have provided Cole a non-working gun to encourage this outcome.)

More evidence:

• the lady scientist says insurance remark on the plane seated next to redhead-ponytail guy, suggesting she was prepared to go to the same destinations, which the scientists had Cole list earlier in the movie
• the scientists may have been worried because Pitt's father changing security procedures, showing Cole could indeed disrupt timeline.
• at one point, a scientist in the future scornfully calls the pre-virus world "that dying world" suggesting no interest in saving it.
• the overall story of the movie is Cole wants to live in the past despite being ordered not to (Cole: "This part isn't about the virus, is it? It's about obeying, about doing what you're told.")

Cole's assignment was not to stop the virus, but to locate the source. The insurance person I believe was sent to get a sample. The virus will spread, because it already has. The goal to the time travelers was to figure out (in the future) how to combat the virus.

Edit: Here is my take on how time travel works (IMHO); Anything that is known in the future is what happened in the past. Therefore you can't change the past except in ways that don't make the future inconsistent with the past. Cole knew about the man (himself) being shot at the airport and I think that the controller that sent Cole into the past also knew and most likely guessed that he was Cole. They also sent Jose with the gun to help Cole to fulfill his destiny. What the controllers want is a way to cure the virus in their time and they need a sample to be able to do that. The insurance lady is there to get the sample. This lady has to be from the future and not her younger self or she would have contracted the virus and died, therefore she would not be in the future. Another indicator that she was from the future is that Cole was 8 years old at the time, Jose when he gave the Cole the gun said something that 30 years had passed (although I think that more then 30 years had passed as Cole looks to be older than 38). The age of the insurance lady didn't appear to be 30+ years younger than the future version.

The caricature of insurance people is that they are like leeches -- that they make their living off of people's fear. Mortality rates and actuarials are not appealing topics. Their paradox is that without tragedy, insurance wouldn't be a viable business.

This conception has existed for years -- well before the bad behavior and negative publicity insurance companies have earned over the past decade. Denying coverage or revoking claims for profit.

Terry Gilliam does what he has always done, and does best! The line "I'm in insurance" is a punchline, absurdism pure and simple. Maximum irony: That insurance woman scores on ultimate tragedy. She is not only immune to the virus, but she prospers in such a way as to become a post-apocalyptic ruler. Ha!

[see Fight Club for a big send-up of greedy insurers]

I actually always saw this as coincidence with her being the "original past version" of this woman, who's unaware of her future.

Whereas your interpretation makes much more sense I have a major problem with it: causality! They cannot stop the outspread of the virus because this would prevent Bruce Willis' and her future actions and therefore the whole movie and their stopping of the virus. And he already let it free in the airport when he opened the glass, didn't he?

Well most movies about time travel don't care about such causality problems, but especially Twelve Monkies is one of the few films (or the only one? maybe Source Code in its own theoretical physical interpretation) I know that handle causality in a plausible way. So I'm pretty sure in the context/story/universe of the movie they cannot prevent the outspread of the virus because all their actions are already prescribed, like Bruce Willis' death in the airport has always been prescribed.

But well your interpretation still makes sense, so I think they could still try to stop him (the characters are still unaware of the causality problems) without success or even heal it in the future, where the story is still open.

So yes, she's likely to be the insurance to stop him. But again, she will not be able to achieve it.

EDIT: In my coincidence-interpretation the "insurance" remarks could also be just a symbol for her, one of the scientists/leaders, being an ordinary citizen in the past, in this case an insurance agent. Similar to the symbol of the Holnist leader being a former copier salesman in The Postman.

Yes, just in-case they couldn't stop him in the airport, she is the backup...insurance. At least that's how I interpreted it.