[bell-cot]

tl;dr; - Scientists did DNA testing on the remains of the Grand Duke and his wife, and found malaria. The rival theory is poisoning by the relative who was next in line for the Ducal throne. HOWEVER, this test result solves nothing:

> But is there any guarantee that Francesco was not also poisoned?

> “Perhaps not,” Ochoa said, “but the genetic evidence presented in our study decreases the margin for speculation.”

> Gisella Caccone, a senior research scientist also at Yale and a study coauthor, agrees. “We can say that they had malaria, we cannot say that they were not poisoned as well,” Caccone said in an email.

[shermantanktop]

Maybe they were poisoned, had malaria, were stabbed, and also suffocated and drowned, all at the same time?

"solves" is a silly thing to ask for in matters of probability. I think this test result adds data which shifts probabilities, and that's the best we'll get.

[themgt]

Maybe they were poisoned, had malaria, were stabbed, and also suffocated and drowned, all at the same time?

Just now learning Grigori Rasputin died of malaria.

[bell-cot]

> "Solves" is a silly thing to ask for...

Maybe? If testing of their remains had revealed (say) LD95 of arsenic, or some other poison well-known at the time, it'd be pretty reasonable to call that "solved". (At least as to their cause of death. It wouldn't establish the perpetrator.)

[shermantanktop]

The justice system works in binary: legal vs. illegal, guilty vs. innocent, admissible vs. not. The whole process is dominated by driving uncertainty into binary certainty, with threshold tests at every turn.

Reality as experienced in the moment is often binary (I am walking vs sitting) but is often murkily probabilistic (am I am tired because I am jet-lagged, or because I flew to give a high stakes presentation?).

History is also a mix, but facts become murkier the older they are.

So sure, LD95 sounds pretty much like we would have solved it. But if enough people wanted them dead, it’s not impossible that a lethal dose could coincide with some other cause of death. That could be my defense if I were on trial for it.

[senshan]

Right. If one lives in an area prone to malaria, has good immune system, will the body tend to carry the antibodies all the time?

[colingauvin]

Yes, which is why the immunological tests done in 2006 were not seen as conclusive. However, this time they found actual plasmodium DNA which suggests active infection at time of death. Including from two species, suggesting double infection. Fun.

[prmph]

I live in Ghana, we have malaria as a common (not too common though) ailment. I have also had malaria several times, though the last time was almost 9 years ago.

As I understand it, some malaria parasites can remain dormant in the body for a long time. Clinical symptoms develop once the parasite burden and immune response become sufficient to cause illness.

Not sure if the couple had made trips to Tuscany before the last one, but it is interesting they found two species of malaria pathogens.

I thought that was also an interesting angle to consider.

[toyg]

> Not sure if the couple had made trips to Tuscany before

Dude, they were the royal family of Tuscany. They lived there. Which is why this test is not conclusive: sure, they had malaria, but at the time it was pretty common in the region and they likely had it for a long time.

[prmph]

Sorry, I meant if the couple were regular visitors to those areas in Tuscany known for malaria. I do agree that this test is still inconclusive, which was the point of my original comment.

From TFA:

> “Francesco and Giovanni, a young member of the family, both traveled 25 years apart to areas of Tuscany which were known for malaria,” Giuffra said.

“The court physicians tried to discourage some members of the Medici family from doing these trips, especially in autumn, which was a season particularly favorable for malaria...”

[colingauvin]

Your comment is a stark reminder that I take for granted that the single biggest killer of human beings in history is simply something I don't have to think about. For some reason, I'd have thought there'd be no overlap between HN commenters and malaria - shows my blind spot.

If what you say is accurate (that malaria can remain dormant) then I agree that I don't see how DNA is proof of how they died. Certainly, regardless of how they died the malaria didn't help, and a double infection is likely even worse, but yeah if you have it chronically then DNA alone is insufficient.

[senshan]

Interesting. Little brother brought a new version of malaria to try...

[bell-cot]

The pedantic answer is "yes".

The pragmatic answer is "if only it was that easy" -

https://en.wikipedia.org/wiki/Malaria#Immune_system_evasion

https://en.wikipedia.org/wiki/File:Global_malaria_deaths_201...

[foobarian]

Or, maybe the poisoner did it by releasing a jar of malaria-laden mosquitoes in the guy's bedroom. Such plausible deniability!