ElanaDec 23, 2023

I cannot believe how poor the penetration is for this story. It feels like I’m manually telling everyone I know, and they’re each hearing it for the first time.

The free rapid tests that Shoppers Drug Mart has been distributing are duds! They throw a false negative at everything but the highest viral loads!! A negative result from one of these is basically zero information!!! Do not rely on them!!!!

Tell your friends, save lives.

https://globalnews.ca/news/10183219/covid-test-supplier-canada/

COVID test supplier received billions in pandemic contracts after submitting edited results

The familiar lime-green kits were not always reliable in detecting COVID-19, experts say, putting Canadians at risk.

Global News
Show threadSara Lobkovich, J.D., NBC-HWCDec 24, 2023
@elana You may have just literally saved our New Years (if not more). We went through all of our other tests this week with my husband sick, and had two boxes of those at the bottom of the pile that we were going to rely on to decide whether it’s safe yet for him to come out of isolation and visit family tonight. I’ll pick up fresh tests thanks to your post. Thank you for sharing!
Show threadElanaDec 24, 2023

@saralobkovich so glad to hear it ☺️ a better quality test will definitely do that job better!

pro tip: any rapid tests are really only about 34% accurate at detecting an asymptomatic covid case! You can improve your odds of bypassing a false negative by testing multiple times, 48 hours apart. Here's a thread + study discussing this more: https://mstdn.science/@DrZoeHyde/110685736952352573

good luck, be safe, wishing your whole family good health!!!

Dr Zoë Hyde (@[email protected])

A new study shows that multiple rapid antigen tests are needed to reliably detect COVID-19. During the first week of infection, a single test has 82.5% sensitivity in symptomatic cases and only 34.4% in asymptomatic cases, compared to a PCR test. 🧵 https://www.acpjournals.org/doi/10.7326/M23-0385

mstdn.science
Show threadSara Lobkovich, J.D., NBC-HWC
@elana I’ve found even the reputable rapid tests to do a poor job of detecting *symptomatic* cases in my household — I don’t know if we just generate lower viral loads, but I tested negative until day 9 of symptoms with my first infection, and with my 2nd I caught COVID at home with my only contact being family members who never tested positive during the window I would have been exposed. I trust positive rapid tests, not negative ones.
Dec 28, 2023 at 3:05amWeb
Show threadElanaDec 28, 2023

@saralobkovich That is the right way to do it for sure!!!!

Stop me if you already know this, but: vaccination trains our immune system to respond more quickly to the virus, so you show symptoms earlier, at lower viral loads—sometimes before there's enough virus for the test to catch! BUT THEN, each infection seems to cause a period of immune dysregulation (currently being researched; 6 months? a year?) whilst you become *more* susceptible to all kinds of infections! Definitely best to avoid!!!

Show threadSara Lobkovich, J.D., NBC-HWCDec 28, 2023

@elana I wasn’t, but I’m at the very careful end of the spectrum w/ Long COVID x 2 (onset of first “type” May 2022 after 1st infection, second “type” with a whole new cluster of symptoms after second infection in March 2023).

That IS really good / important data for me in case of another known exposure when managing high risk treatment timelines. Are PCR tests prone to potential false negatives due to the same dynamic? (I also tested negative on PCR during my first infection.)

Show threadElanaDec 28, 2023

@saralobkovich oof I am so sorry to hear about your long covid 😣 that sucks so much. Lots of precautions solidarity from me & mine 🫶

I’m certainly no expert but PCRs are *supposed* to have greater sensitivity, but I am hearing a lot of stories about lab tests coming back negative, then testing again and returning a positive, just as you’re saying 😣 it’s no wonder the technology can’t keep up with a rapidly evolving virus that we’re letting mutate freely in as many hosts as it likes 😓

Show threadMonika ViktorovaDec 28, 2023
@saralobkovich @elana are you testing with the updated testing protocols? We all have high immunity in nasal and oral mucosa so we don’t shed as much virus. Best sensitivity is swabbing cheeks, throat and nose - both sides - at least 10s each.
Show threadElanaDec 28, 2023
@mviktoro great tips! Better swab technique does catch a few positives that you mightn’t otherwise. But the false negative rate on rapid tests is still bad enough that I wouldn’t bet my life (or anyone else’s) on one.