If time to kill before becoming infectious increases then the host can travel further before infecting others and so spread a disease outside an affected area.

If this strain of ebola was killing ~90% in a few days, rather than ~50% in a week or so, then it probably would never have spread this far.

In terms of public health if it had been a lot more deadly to the individual, then it would probably have killed a lot less people overall.

Most outbreaks of an infectious disease become less deadly the further they spread as the longer lived hosts are the one's more likely to be able to pass things on.

No. That is not correct. And that is my point. The virus can only infect more people if those infected with it are left to roam freely in the general population. If, for example, everyone is diagnosed within three days of showing symptoms it doesn't matter if time-to-kill is 10 days or 30 days. Those infected will be identified and isolated within the first three days. So, the virus will not infect more people.

What you are saying is absolutely true if society breaks down and infected people are free to roam and transmit the virus or if viral control mechanisms (identification, isolation and treatment) are substandard or nonexistent.

> If time to kill before becoming infectious increases then the host can travel further before infecting others and so spread a disease outside an affected area.

You are confusing time-to-kill with time-to-becoming-contagious (or whatever we want to call it). One does not imply the other. I am only asking about justification for time-to-kill being important in the context of the identification and isolation of people who are contagious within N days of showing signs. As I said before, if you catch them within N days and isolate them the fact that people can die within X days or 2X days is utterly irrelevant. If you don't isolate them the situation is, of course, very different.

> If this strain of ebola was killing ~90% in a few days, rather than ~50% in a week or so, then it probably would never have spread this far.

I don't think this is true either. The death of the person carrying the virus is NOT the end of the virus. A virus killing the infected in five days vs. ten days might be far worst. It depends on a huge number of factors. For example, take the case of a person who takes the subway to go to work every day. He becomes contagious after 21 days and does not go to the doctor until the fourth day. He has potentially infected a massive number of people. The fact that he dies on day 5 or day 10 is meaningless. The only way it could become meaningful is if this person, again, is roaming free after becoming contagious.

I think what's going on here is that many are making the assumption that people will do just that: No medical attention, no isolation, just going around infecting people for days and days without a care in the world. That's not the way things work unless society completely breaks down. Hence my questioning of the assertion that a longer time-to-kill is, by itself, significant in any way.

So I say again:

It is absolutely crucial that we take these outbreaks as the existential threats they represent. They can start small and virtually without notice. People run a fever pop some pills and continue about life for a few days. Failing to recognize the need for serious medical attention they go about life and infect many more. When they finally feel crappy enough to go to the doctor they've already set the chain reaction in motion. If medical professionals are not on their guard and dismiss the patient they could make things worst as well as exposing themselves and other medical professionals to the active virus. Imagine an outbreak of 50 or 100 cases in a city like Austin, TX. It will quickly change society for quite some time. If medical professionals fall victim it will only add a scary layer to the equation. The key to all of this is to both prevent it from reaching our shores and, if it does, have a massive information and awareness campaign to be able to stop it. It wouldn't take much to be in a situation where you have to ground every plane in the US and tell people to stay home for 21 days if a large enough outbreak happens in a mid to large city.

The key is prevention and quick isolation.

Not sure why we still have flights incoming from the afflicted areas without having them land at a military base for a mandatory 21 day holding period before contact with the general population.

I really hope this doesn't derail.

Tell that to the healthcare workers who are having to treat patients in full suits and are still getting exposed. It doesn't matter where you are, the longer you are infectious, the more chance you have of infecting someone, so strains that keep you alive longer are more likely to be passed on.

You are confusing time-to-kill with time-to-becoming-contagious

I misworded it cos I was tired, but yes I did mean time to becoming contagious for the second point.

Let's see. If it's number one, well, it has nothing to do with the time it takes for the virus to kill the patient.

And, guess what? If it is number two it also has nothing to do with the time it takes for the virus to kill a patient. They are probably using the wrong suits. Or maybe they e Were damaged . Or maybe they were reused or not sanitized or...

Once a patient is identified and quarantined properly and all safety procedures are followed the time that the virus needs to kill the patient is utterly irrelevant as it pertains to spreading the disease. That should hold for all normal circumstances.