"If the difference is the inverted section on plasmid, then we did know that back in 2002. That is the way I read the Read article in Science. I even wrote to a guy at TIGR and he confirmed that I was reading it correctly."
That's beyond me. I do remember first reports in 2001/early 2002 of a "genetic" difference between (I think) the AMI and a senate anthrax - but a scientist, from Stanford I recalled, commented that it might not mean much, there's all sorts of reasons for vairations, etc.
There was also the reports about the difference between the Daschle and Leahy anthrax - one was "clumpy" and looked like "puppy chow." This was later explained as after the fact damage by irradiation, water, or something else.
"There was a question if what was sequenced from Bob Stevens had been influenced by the massive amount of antibiotics he
was given, but they could have, but I never heard the results....compare it with what was in the unopened envelope to the Senator. If they compared the two and they both had the same 50% inversion, then the antibiotics had no effect. It was like that supposedly when they stole it. My scenario is that they stole it by taking a little out of a couple of vials. Then it would not look like any was missing and the thief would be long gone by the time any discovery was made."
My first question would be why the Leahy anthrax wasn't compared to the AMI anthrax, rather than via Stevens' blood. But maybe there wasn't enough found at AMI to make a test...is that true? Sounds a little familiar.
Then there's that story of the Egyptian sailor in Brazil that's never been explained...
I think this analysis might still be of interest today. Below are copies of a couple of posts about this. (I think there were earlier postings, but these are probably the clearest and most complete.)
There do appear to be differences in symptomatology among the various anthrax mailings. It's too early to say whether these differences are caused by genetic differences in the anthrax, different physical preparation of the powder, or some other differences in the patients or the environment.
There are three differences in symptoms, of which two appear to require further explanation:
Differences 1 and 2 above may not be statistically significant, due to very small sample sizes (especially in Florida); but they are suggestive of a difference.
If I had to guess, I'd say that difference 1 would appear to be due to a genetic difference between the FL anthrax and the anthrax distributed in the Northeast. It could also be due to some other difference (a chemical agent added to the NY and/or DC anthrax, or some other aspect of the physical preparation). (Or maybe it's just due to chance. Perhaps Blanco in FL was unusually hardy. But he's quite old, which makes me doubt that it's just chance in this fashion.)
Difference 2 is strange. The same bacterium causes both inhalation and cutaneous anthrax; the difference is just the site of infection. My first inclination was to say that this difference indicates a difference in physical preparation (after all, the whole point of "weaponization" is to make the particles small enough to lodge in the lungs, as well as to make them free of electrical charge so they'll move around easily) or in delivery method. But the delivery methods were apparently the same. And what kind of physical preparation could prevent cutaneous anthrax cases from arising at AMI? The building was heavily contaminated, after all.
So I'm not sure what to make of difference 2. Maybe it indicates a genetic difference as well? There could be different genetic propensities for the bacteria to do differentially better or worse at different infection sites.
Let's analyze this statistically. Take as the null hypothesis the statement that there is no difference between the FL and NJ anthrax. Of the 6 inhalation anthrax survivors, 1 refuses to be interviewed. So, of the 5 we know about, 1 (Blanco) has fully recovered, and 4 are experiencing the syndrome of symptoms described in the article (memory loss, fatigue, joint pain). Assuming the null hypothesis now, all patients were exposed to the same anthrax; this anthrax would then appear to cause this syndrome among about 80% of the survivors (due to genetic differences among patients or other factors). The fully-recovered patient could equally likely have been any one of the five (by the null hypothesis). The probability that the fully-recovered patient (we would expect to have one) would be the patient from FL is 1 out of 5, or 20%.
So I conclude that the probability that this is due to chance (rather than to some difference between the FL and NJ anthrax) is 20%. In statistical terms, we can say that there is a difference between the FL and NJ anthrax at the p=0.8 confidence level. This is not statistically significant (because of the small sample size), but it's high enough to be suggestive. It does add to the weight of other evidence that there is a difference.
In terms of other measures, notice that there doesn't appear to be a difference in mortality rate between the FL anthrax and the NJ anthrax, among the people who contracted the inhalation form of the disease. Fatalities numbered 1 out of 2 cases in FL, and 4 out of 9 cases in the Northeast.
On the other hand, there does appear to be a difference in the site of infection. There were many cases of cutaneous anthrax in the Northeast, but none in FL. This suggests a difference in physical preparation or delivery method, but it's conceivable that a subtle genetic difference could make one type more virulent at a particular site than another.
There's one minor correction to make here. I wrote: ...at the p=0.8 confidence level.
I meant, of course, the 80% confidence level, or, equivalently, p=0.2. (Typically, people would like to see a 95% confidence level, or p <= 0.05, to call something statistically significant.)
This p value of 0.2 is based just on the differential rate of full recovery among survivors in the two populations (FL vs. the Northeast). I suspect that if you also include the difference in cutaneous anthrax incidence rate, the difference may prove to be statistically significant.
Yes, I recall that too. There were supposedly small genetic differences between the FL anthrax and the DC anthrax. What I heard was informal second-hand talk, though, not verifiable published information.
I know of one published article that appears to allude to this. It's a Washington Post article from Aug. 4, 2002, http://www.washingtonpost.com/ac2/wp-dyn?pagename=article&contentId=A40838-2002Aug3. Here's a short excerpt with the relevant allusion:
One law enforcement official confirmed that tests are still underway on the spores recovered from a letter to Sen. Patrick J. Leahy (D-Vt.). "There is still optimism that the science will narrow this thing down further," he said. But he acknowledged that "the science is only going to take us so far."It sounds as if they were saying that they found small genetic differences, but that they weren't sure exactly what to conclude from that.
The problem for analysts is that while they can compare genetic material from different samples, or "isolates," of the Ames strain, they do not yet know how to interpret the mutations that can occur across generations of a bacterium, or even among different bacteria from the same lab and strain.