May 30, 2012

Chagas Disease — the “new AIDS of the Americas.”

The "new AIDS"... and "[n]ew research suggests Chagas may have led to the death of Charles Darwin — one of the great medical mysteries." Doesn't sound so new!
Darwin wrote in his diary that he was bitten by a “great wingless black bug” during the trip in 1835. He died 47 years later of heart failure.

15 comments:

oldirishpig said...

If it takes 47 years to kill you, this might be a 'scourge' we canive with. Pun intended.

virgil xenophon said...

I thought that spot was taken by Lyme disease..

chickelit said...

It does seem to have more in common with Lyme disease given the insect vector.

Ken Green said...

Chaga's disease is really quite nasty - most of the trypanosomes are. The problem is not so much that they kill you right away, the problem is that they steadily debilitate you over time.

I worked with one strain in a lab as an undergrad, and thought I'd accidentally infected myself. The paranoia didn't go away for years.

Carnifex said...

It's carrots I tell you! 100 percent of the people who eat carrots will die at some point in their lives. Think about that! 100 percent! And where is Zero? where is Moochie?! They're pressing these orange sticks of death on our children, that's where!

Of course it's death to eat a carrot. Look where their grown! In the ground! Where any dog can come along and pee on them! And fertilizer! Good God!

Down with Zero! Down with Moochie! Make them eat their own dirt swaddled sticks of death!

edutcher said...

I have a feeling we've found our next big media-driven panic.

Paco Wové said...

I knew a guy who got leishmaniasis. As I recall, the course of treatment was pretty rough, lots of heavy metals to poison the parasites just enough more than they poisoned the patient.

Crimso said...

There is a belief that the disease is primarily a problem in Central America. A shocking number of dogs tested in the state of Tennessee some years back (2007?) tested positive. It's here, most people just don't know it yet.

Crimso said...

Factors associated with Trypanosoma cruzi exposure among domestic canines in Tennessee.

Rowland ME, Maloney J, Cohen S, Yabsley MJ, Huang J, Kranz M, Green A, Dunn JR, Carpenter LR, Jones TF, Moncayo AC.

J Parasitol. 2010 Jun;96(3):547-51.

Scott M said...

Factors associated with Trypanosoma cruzi exposure among domestic canines in Tennessee.

Yes, but will it lead to humans abandoning dogs as pets, leading to wholesale adoption of chimps, leading, invariable, to said simians becoming "damned dirty"?

bagoh20 said...

Years ago I had one of those foster children in Guatemala that you send money to every month to help her family. They would send me photos and letters. A very cute little girl. One day I got a letter saying that she had died of Chagas. She was 8 years old.

Dave said...

"In this study, we report a seroprevalence of 6.4% among 860 canines from 31 counties and 5 ecoregions throughout Tennessee, using an indirect immunofluorescent assay"

Crimso,
6.4% is certainly higher than I expected but not that high. Also in order to evaluate this paper you need to know more about the specificity of the antibody, which isn't clear from the abstract. If there was microbial DNA confirmation (qt-PCR), the findings would be more compelling. I can't see the full article because it's behind a pay wall, which is atypical of Scientific journals.

Are you a microbiologist? I'm a plant physiologist by training, although I work on cancer these days.

PatCA said...

Chagas is making its way into the US. It can be stopped by our most common hygiene practices, like washing your hands often if you work in a restaurant, but to say that is racist or something.

Crimso said...

I'm a biochemist (you might say I work on cancer, though not as much as I used to). That was just the first thing I got my hands on. I recently sat in on a seminar by one of my colleagues dealing with this very subject. He went into more detail, and I vaguely recall him showing other data that were eye-opening. What was particularly interesting was the breakdown by county, with my county of residence having a relatively high incidence of T. cruzi in canines. We also have a particularly bad problem with rabies here.

I'm quite aware of the caveats. I can't read any research and not automatically look for the flaws. They could be underestimating the incidence as easily as overestimating (based on Ab specificity; I'm not currently at work so I can't dig into the paper to see if they did PCR).

The fact that it appears at all tends to go against the conventional wisdom that this is a Central American problem. How likely are physicians in Tennessee to dismiss Chaga's in the process of diagnosis? If 1 in 15 dogs has it (more where I live), aren't people at a considerably higher risk than previously thought?

OldGrouchyCranky said...

Chargas disease results in the heart becoming enlarged and then no longer functional. During the 1970s, Medtronic had a device which could stop the progression of that disease yet it seemed that there awas no effort to promote that use to minimize that disease. Pity!