John Carlson @johncarlson.bsky.social · 06/08/2026Yesterday I heard about a third fatal cases of venom-induced anaphylaxis this year. It’s especially sad because reactions are preventable with desensitization. As in this case, epinephrine does not always work, so desensitization is really important for anyone with prior anaphylaxis from a sting. 010
John Carlson @johncarlson.bsky.social · 26/11/2025The Wedge-shaped Beetle, Macrosiagon cruenta, ambling around on flowers near the Mississippi River 0292
John Carlson @johncarlson.bsky.social · 27/09/2025Late September is when green leaves turn into yellow butterflies here in New Orleans. 1809
John Carlson @johncarlson.bsky.social · 27/09/2025A pale-legged flea beetle, Lysathia ludoviciana, looking contemplative at the leaf’s edge. 2515
John Carlson @johncarlson.bsky.social · 21/09/2025The Bronzed Tiger Beetles (Cicindela repanda) scampering along the Mississippi River beaches have subtle iridescent colors when you look closely. 411120
John Carlson @johncarlson.bsky.social · 20/09/2025A Hibiscus Scentless Plant Bug, Niesthrea louisianica, on the edge of a hibiscus flower in the Mississippi River flood plane 2495
John Carlson @johncarlson.bsky.social · 19/09/2025Despite the unusually dry weather we had a successful Bug Walk in Audubon Park and nearby neighborhood to find insects of medical (and non medical) relevance. This year we had folks download @inaturalist.bsky.social (or Seek) to practice documenting the biota in the city. 1192
John Carlson @johncarlson.bsky.social · 19/09/2025What a beautiful insect, and posing so nicely for this photo! 0333
John Carlson @johncarlson.bsky.social · 15/09/2025Looking back I didn’t upload any photos in 2013; it was when we did a repeat BioBlitz at Jean Lafitte 2016 that I brought a group of Allergy/Immunology fellows and took my first photo. Incidentally that was the start of my annual Allergy Bug walk for fellows. How it started / How it’s going 0180
John Carlson @johncarlson.bsky.social · 14/09/2025My first post on @inaturalist.bsky.social was a Metric Paper Wasp (my favorite paper wasp) as part of a National Geographic supported, invertebrate-focused BioBlitz in Jean Lafitte National Park in 2013. And now it is my 20,000th post also! 5401
John Carlson @johncarlson.bsky.social · 14/09/2025It’s very dry here in New Orleans; plants are crisping up and the insect activity is way down. An exception is this wasp, clamoring over flowers, perhaps using nectar for hydration 0668
John Carlson @johncarlson.bsky.social · 13/09/2025I finally got a flash for my camera so that I could increase shutter speed. My first subject was one of the frenetically bumbling bumblebees crashing into flower after flower. I didn’t get a great photo of the bee but you can see the pollen floating away from the flower which is really interesting 3523
John Carlson @johncarlson.bsky.social · 12/09/2025A pretty Thread-waisted #wasp meandering through the vegetation at Bayou Savage in New Orleans 2813
John Carlson @johncarlson.bsky.social · 11/09/2025A Question Mark #Butterfly sipping Mississippi River water on the sandy shores under an exceptionally bright sun this past weekend 0242
John Carlson @johncarlson.bsky.social · 08/09/2025A Four-spotted Pennant #Dragonfly perches next to the Mississippi River as it bends around the city of New Orleans. 0283
John Carlson @johncarlson.bsky.social · 31/08/2025Exploring Bayou Savage in New Orleans East I found this weevil posing on the beautiful backdrop of a flowering Saltmarsh Mallow. 2795
John Carlson @johncarlson.bsky.social · 24/08/2025This afternoon I discovered that my boots are no longer waterproof but that they remain mosquito proof. Tested simultaneously by water in the Mississippi River flood plane and by several Psorophora columbiae mosquitoes that live there. 1230
John Carlson @johncarlson.bsky.social · 22/08/2025An Anchor Stink Bug instantly before it took flight. Photo taken last weekend on the shores of the Mississippi River. 1495
John Carlson @johncarlson.bsky.social · 22/08/2025Two large halictid #bees (I think Nomia nortoni) enjoying some midday sun. 1353
John Carlson @johncarlson.bsky.social · 22/08/2025#EntomologyConsult: a patient has an enlarging, progressively itchy, edematous area on her forearm with similar lesions on skin not typically covered by clothes. Bedbug inspection found no insects. This is atypical of her mosquito bite reactions. What could have caused this? 250
John Carlson @johncarlson.bsky.social · 21/08/2025#EntomologyConsult: a child was stung on the hand by an ant, but with pain beyond what is expected for a typical fire ant sting. Is this species more dangerous? My answer ⬇️ 3171
Reposted by John CarlsonJagriti Paul @pauljagriti.bsky.social · 18/08/2025Had the privilege of leading Pediatric Grand Rounds at Ochsner Children’s last week. Presented a preterm case that turned out to be a real zebra—a high-grade bowel obstruction from congenital adhesive bands in a 33-weeker. Not your “bread & butter” NICU day. #NICU #Neonatology #Pediatrics 011
John Carlson @johncarlson.bsky.social · 18/08/2025A soldier #fly, Hoplitimyia mutabilis, resting under the hot summer sun near the Mississippi River 0361
John Carlson @johncarlson.bsky.social · 16/08/2025Happy bees! I wonder if Hibiscus flowers may be too much of a good thing for bees. They can get plastered with the sticky balls of pollen! Hibiscus plants grow wild along the Mississippi flood plane and I can spend a lot of time watching these goofy insects coating themselves in the copious pollen. 2552
John Carlson @johncarlson.bsky.social · 15/08/2025I’m not particularly superstitious but on days that I do especially high risk protocols in the allergy clinic I wear ties that have ladybugs, a symbol of good luck. Today I wore my ladybuggiest tie and am pleased to report that things went well! 6461
John Carlson @johncarlson.bsky.social · 08/08/2025We had one potential case of locally acquired Chagas’ disease in New Orleans: infected bugs were feeding indoors on someone then diagnosed with infection. Even then it’s uncertain if she got it here vs earlier in life in another country. How do dogs handle it? pmc.ncbi.nlm.nih.gov/articles/PMC...pmc.ncbi.nlm.nih.govAutochthonous Transmission of Trypanosoma cruzi, LouisianaAutochthonous transmission of the Chagas disease parasite, Trypanosoma cruzi, was detected in a patient in rural New Orleans, Louisiana. The patient had positive test results from 2 serologic tests an... 3102
John Carlson @johncarlson.bsky.social · 08/08/2025Babesia is a tricky infection to diagnose because the symptoms are so general: Fever and feeling sick. As the climate warms, exposure to this ticks increases, along with the many, many pathogens that they transmit. 0100
John Carlson @johncarlson.bsky.social · 08/08/2025Thankfully transmission of T cruzi to humans is rare in the US because the species of kissing bugs we have don’t feed on people very often, and when they do, usually don’t defecate while feeding (needed to get the Protozoa into the bite wound). But cases do happen and are probably under-diagnosed. 1298
John Carlson @johncarlson.bsky.social · 07/08/2025Becoming allergic to your research organism is miserable! Read this great article to hear about examples of allergies to butterflies, leeches, snakes and more that develop in people that study these creatures. 1121
John Carlson @johncarlson.bsky.social · 07/08/2025Our hospital has therapy dogs come and visit patients, each dog with their own hospital badge. This rarely seen Cryptocephalus cupressi is a case-bearing leaf beetle, found just outside the hospital entrance. It feels like a therapy beetle but it didn’t have a badge so I didn’t let it inside 2401
John Carlson @johncarlson.bsky.social · 07/08/2025A Clavate Tortoise Beetle, Helocassis clavata, pokes its antennae out into the dangerous world. 4362
Reposted by John CarlsonAlli’s Nature Journal @anaturejournal.bsky.social · 06/08/2025Black-waved Flannel Moth Caterpillar. A whimsical encounter! Best to keep distance if you cross paths because under those wispy, white hairs are venomous spikes that will sting! #MegalopygeCrispata #bugsky 2442
John Carlson @johncarlson.bsky.social · 05/08/2025She thinks I’m sweet... Aedes triseriatus on my leg. 4292
John Carlson @johncarlson.bsky.social · 04/08/2025This tiny robber fly was busy snacking, so was able to creep up pretty close to get this photo. 4995
John Carlson @johncarlson.bsky.social · 04/08/2025A Green Coverworm Moth landed on a red flower just long enough for a photo last night. Nice red eyes to match the red flower. 😍 0341
John Carlson @johncarlson.bsky.social · 02/08/2025Paper wasps are not particularly aggressive, but they do sometimes build nests that get easily disturbed, eg this nest in the hollow portion of a metal gate. When the gate gets opened or closed the workers fly out and sting anyone that might be a danger to the nest. 3282
John Carlson @johncarlson.bsky.social · 01/08/2025Most Southern Flannel Moth caterpillars are killed by parasitic flies or wasps before reaching their fluffy adult form. This year I’ve seen far more adults than any other year. If the flies and wasps don’t pick up it might mean 2026 will be a bad year for caterpillar stings. 🫣 0525
John Carlson @johncarlson.bsky.social · 31/07/2025A longhorn beetle, Dectes texanus, sheltering under a leaf along the Mississippi River flood plane this past weekend. 2411
John Carlson @johncarlson.bsky.social · 30/07/2025Passionflower vines are native plants that have beautiful flowers, and are the food for the striking Gulf Fritillary caterpillars that grow up to be gorgeous butterflies. Who gives out the awards for Best Looking Plant/Caterpillar/Butterfly Combination? I’d like to make a nomination. 2495
John Carlson @johncarlson.bsky.social · 30/07/2025Fascinating! This treehopper was probably using its helmet to sense my presence through electrostatic cues on Prince Edward Island last summer. What an incredible way to sense the world! 2453
John Carlson @johncarlson.bsky.social · 29/07/2025A Leafcutter bee sipping nectar under a blindingly bright summer sun. 1796
John Carlson @johncarlson.bsky.social · 28/07/2025A Needham's Skimmer dragonfly overlooking Bayou St John yesterday afternoon. 0351
John Carlson @johncarlson.bsky.social · 28/07/2025A Two-spotted Longhorn Bee collecting pollen across from Bayou St John yesterday. 0543
John Carlson @johncarlson.bsky.social · 28/07/2025A Common Thread-waisted wasp, Ammophila procera, drinking nectar near Bayou St John this afternoon. 1674
John Carlson @johncarlson.bsky.social · 27/07/2025Along the Mississippi River just south of the New Orleans Airport, A Megachile bee lifts into the air 2564
John Carlson @johncarlson.bsky.social · 26/07/2025A Painted Coreid bug in the Mississippi River flood plane in St Rose, Louisiana, a short drive upriver from New Orleans. 0584
John Carlson @johncarlson.bsky.social · 24/07/2025A checkered skipper resting on a little frogfruit flower in the 9th ward, New Orleans. 313620
John Carlson @johncarlson.bsky.social · 23/07/2025I’m not sure how to crop photos of Orthoptera with crazy long antennae. It feels rude to cut them off, but my goodness it means making the rest of the insect a smaller piece of the photo. Here is a Restless Bush Cricket to demonstrate the conundrum. 0301