That’s assuming that the virus doesn’t mutate any further.

(Did not downvote you. It isn’t a good subject, but we do need to talk about it)

1. Nobody really knows for sure. Predicting the future worst case by comparing it the worst instance from the past in the category is a fallacy (I get the sense you're comparing it to the spanish flu, but consider that the past "worst case" was already surprising to people back then because it was worse than the "past's past")

2. It's not enough to look at pure probabilities, it's also necessary to consider the magnitude of loss for each outcome. For example, Russian Roulette with 100 slots for $100 has a median gain of $100 per round, but you wouldn't want to play that game.

3. I'm not brave enough to put my money on the line but if you're confident you could buy long term options on airline companies and make out like a bandit when travel recovers.

Not right now. The implied volatility, aka the cost of options, is too high.

For example, American Airlines, symbol AAL, closed Friday at about $16 per share. If you go to January 2021, the cost of a $20 strike call is about $3. So you need AAL to rise from $16 to $23 just to break even. That's almost a 50% gain needed, in less than a year.

The cost of options will get much cheaper once the market settles down (even if current price levels stay the same). If the market sits in the doldrums for a few months (not moving up or down very much) then option prices will fall.

You need to buy options when they're cheap, not when they're crazy expensive.

In low vol periods: if stock is at $2, it is likely to stay at $2 since vol is low. So maybe a $3 option is worth 10 cents. But there are very few people in the market so there's going to be a large big-ask spread. Nobody's going to sell it at 10c; there are few other sellers so you can offer it at 15c and rip off the buyer since they have no choice.

At high vol periods everyone wants to be in the market so the price will actually be close to the 10c theoretical price - less spread (what you. All margin). But since there is high vol the stock is more likely to get to $3 so the option could be worth 20 cents instead of 10.

Volatility affects price; market volume affects spread.

Sydney winter for example is around 10C, and rarely drops to 5C. Joburg's winter mean is about 10C.

Compare that with London, New York and Beijing.

That doesn't necessarily mean they'll succeed every time though, or that they'll respond as aggressively to a dangerous background virus as to a novel one.