Why I Don’t Think Ms. Kelly is Going to Get Chagas’ Disease

I received this question from Asia Kelly the other day:

Dr. Lerner, thank you for the informative post about Chagas disease. I am a biology student at the University of Texas Pan American in the Rio Grande Valley, South Texas. Last night I believe that I saw an “assassin bug” last night outside of my home near my front door. I am a little worried because I frequently sit outside at night on my porch and I get bitten by what I assumed to be ants or mosquitoes. I’m concerned that I may have been bitten by this insect. I’m wondering if the bite from that bug would cause a rash, swelling, or any sign that it has bitten me. I’m actually very concerned. Also, TV personality Dr. Oz said in a recent show that there is no cure or treatment and that most people will die from chagas in about 20 years. I’m interested in your opinion about this and I’d like to know of any information you might know about the prevelance of this disease in my area. I looked for your email on this site, but cannot find it. Thank you so much.

Ms. Kelly:

You would have to be extremely unlucky to get Chagas’ Disease in the United States. Although Trypanosoma cruzi, the parasite responsible for Chagas’ Disease does exist within our borders, there have only been 7 autochthonous cases, meaning cases acquired here. Admittedly, at least three of those cases were in Texas, but all of those cases were infants, which points out another reason why I don’t think that you are going to get Chagas’: Assassin (kissing) bugs are big bugs, around 2 cm in length. If one gets on you or bites you, you are likely to know it. You can get bitten in your sleep, but we have to remember that it is unlikely that the bugs are in your house. Typically, they live in the cracks in the walls of mud houses, between the bricks of unplastered walls, or in the fronds or thatch that are used for roofing. Some species live outside (like the  North American species of triatomines), but these species–judging by the lack of autochthonous cases in the US–don’t seem to pose much danger.

Furthermore, remember that the infectious material is not the insect’s saliva, as it is with tick-borne or mosquito-borne diseases (like ehrlichiosis and West Nile Virus). The parasites are found in the feces of the assassin bugs. That means that if the insect doesn’t defecate while it bites you, it can’t infect. Apparently, the triatomines that we have here in the US don’t have that behavior.

So, while history has shown that it is possible to acquire Chagas’ disease in the US, it has also shown that it is extremely unlikely. Perhaps this will change, either to due to global warming, evolution, or the introduction of a competent vector–either inadvertently or intentionally–into the United States.

As far as vector -borne disease in the Rio Grande Valley go, I’d be more worried about those transmitted by mosquitoes. Dengue, for one,  has reared its ugly head along this area, and will probably do so again.


3 responses to “Why I Don’t Think Ms. Kelly is Going to Get Chagas’ Disease

  1. I was bitten on the face by an Assassin Bug (we believe the Blood Sucking Cone-nose) in Dalton, GA in 1991. I am also concerned about Chaga’s Disease.
    I’ve developed a laundry list of symptoms that all correspond with Chaga’s.
    These nasty bugs are everywhere. We’ve found three very large critters on our front porch in N. GA within the last 2 months!

    • Have you been tested? If your symptoms are, in fact, a result of Chagas’ Disease, it is likely that you would test positive. What are your symptoms?

  2. Hi I am happy to have found this post. I was bitten by what looked like an assassin bug in 2003. It was an experience that I will never forget. I was walking across a lawn at Fresno State University in Southern California when this bug leaped out of the grass and onto my leg. It had very strong muscles in its legs because I couldn’t shake it off. I had to pluck it off and it took some effort on my part. It had a similar coloration on its edges to a bee. My leg soon began to swell to an incredible degree I am a fairly slim woman and if you had looked at that leg alone you would honestly think I weighed 300 lbs at least. I fell asleep under a tree from exhausted after this happened and I think I recall that it was painful as well. The swelling did go down and by the time I went to the doctor there was little more than a little scar where the insect had bit me. My doctor wouldn’t test for Chagas and told me I was fine. This upset me but I just accepted what he said and went on with life.

    I do have many health problems, pre-dominantly headaches, migraines, pain in my joints and back, lethargy/fatigue, intolerance to heat, depression, anxiety, acid reflux, allergies and sinus problems, and incontinence. As well as a whole host of skin rashes including a red rash on my face that looks like lupus but has been diagnosed as rosacea so far.

    Any feedback would be appreciated.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s