⚠️ FDA says: don't swab your throat for rapid antigen tests that are designed to be used with nasal samples
Closed replies to this ^^ b/c misinformation was being shared, and b/c several replies ignored the text in the FDA's tweet— a sign of troll- and bot-like activity.

I answered some of the questions. For the rest, I urge you to read the FDA's thread (👀⤵️)
Several noted that other countries, like the UK and South Africa, recommend swabbing the back of the throat. Please note that the studies other countries use to support their guidance is based on tests available in *their* country— tests differ in the US, hence the FDA's notice
Though I have no direct knowledge, I strongly suspect that U.S. rapid test manufacturers are gathering the data they need to support (or reject) changes to user instructions. I say this because: capitalism (i.e. they are financially incentivized to gain a marketing advantage)...
If there are data-driven changes to the way rapid antigen tests available in the U.S. are used, you better believe that the first company to score an updated emergency use authorization will tout its scientific prowess in splashy ads b/c, sadly, that's how U.S. healthcare works
I have looked for studies evaluating swabbing for rapid tests used in the U.S. and found 2 pre-Omicron studies. One shows that *adding* saliva sampling doesn’t improve Panbio (BinaxNow) sensitivity & *only* sampling saliva makes it worse

see: ncbi.nlm.nih.gov/pmc/articles/P…
The other pre-Omicron study shows that the sensitivity of *professionally-collected* nasal swabs is higher than for throat swabs, which is better than saliva swabs for Panbio (BinaxNow): ncbi.nlm.nih.gov/pmc/articles/P…
Sorry, I just found this other pre-Omicron study that evaluated the sensitivity of *professionally collected* throat swabs for use in the Panbio (BinaxNow) rapid antigen test. When collected by trained professionals, throat samples are on par with nasal

Now, what about Omicron? That’s where the data falls short. I’ve had several persons cite a study out of South Africa that suggests that saliva swabs yield better results for Omicron. That study is evaluating *PCR* testing— and the evidence is rather weak

There’s *a lot* of nuanced data that I’m not even discussing because it gets into the weeds very quickly— for example, data about saliva vs. nasal swabs in the setting of symptoms vs. no symptoms.
The upshot is: there are a lot of smart people working on this that *aren’t* on Twitter, including most of the scientists that developed the actual tests. What they’re saying *at this time* is: use rapid antigen tests as instructed.


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More from @DataDrivenMD

7 Jan
🧵/Remember when I said that New York would end up with a higher total number of patients in the hospital because most hospitals already reported numbers that excluded *with* #COVID19? Well…
2/ ⚠️ As I said, the data reported to HHS already excludes hospitalizations *with* #COVID19. Here’s an apples-to-apples comparison of pediatric hospitalizations using HHS data vs. New York state data:
🔸Dec 19-Dec 24: +3 HHS overcount
🔸 Dec 25-Jan 1: -87 HHS undercount
3/ The difference stems from the fact that hospitalizations are the result of a simple equation:
# patients admitted - # of patients discharged

I wrote a short thread about this yesterday 👀⤵️
Read 7 tweets
7 Jan
PSA: hospitalizations and admissions are fundamentally different metrics— they're not comparable. Example:

A hospital reports 100 COVID-19 hospitalizations on consecutive days. That could mean:
🔸0 admissions - 0 discharged
🔸100 admissions - 100 discharged
🔸any combo netting 0
^^That's just scratching the surface. There are #COVID19 admissions that may not count toward daily hospitalizations— like short stays lasting <24 hrs

From a patient's POV: they were hospitalized

From a reporting standpoint: daily hospitalization totals may not reflect the stay
^^Yet another nuance: the patient's condition upon hospital discharged. Are they deceased? Were they transferred to another hospital? Were they transferred to a subacute or rehabilitation hospital? Or are they able to go back to their daily routine?
Read 5 tweets
6 Jan
🧵/NEW: Preliminary study findings suggest that “in addition to reducing the risk of acute illness, COVID-19 vaccination may have a protective effect against [#LongCovid]”
2/ “Of the 951 participants, 337 (35%) reported not fully recovering from the initial COVID-19 symptoms at follow-up. The most commonly reported symptoms at the time of follow-up were fatigue (22%), headache (20%), and weakness in arms or legs (13%)”

3/ “After adjusting for duration of follow-up and presence of symptoms at baseline, a 54-82% reduction in reporting symptoms among those fully vaccinated for seven of the ten most commonly reported symptoms was detected (Table 3).”

Read 4 tweets
6 Jan
Look at it this way: at least now you know which public health experts and pandemic pundits are MAGA supporters behind closed doors.

I still can't figure out why the Biden WH keeps amplifying their hot takes, tho
What they're saying in public now is exactly how they've been talking in DMs & emails for 21 months. They don't give AF about working families or BIPOC communities. I've tried to show several of them how their policies fall short, but they honestly believe we should be *grateful*
I straight up asked one of them: "Do you believe racism is a public health crisis?" Their response was, "I feel like this is a trick question."

Read 6 tweets
5 Jan
::whispers:: Volunteers were doing this work since mid-March 2020 and I was in touch with senior Biden Administration officials in Nov. 2020…they went radio silent, and volunteer enthusiasm waned so the effort shuttered in mid-October 2021.
And yes, scam COVID-19 testing sites are a real problem— and they’ve been a real problem since the earliest days of the pandemic.
Read 4 tweets
5 Jan
⚠️👀 “On days 0 and 1 following a positive PCR test, all of the antigen tests used produced false-negative results, even though in 28 of the 30 cases, levels of virus detected by the PCR test were high enough to infect other people.”
🔥🔥🔥 “In four cases, researchers were able to confirm that infected people transmitted the virus to others during the period before they had a positive result on the rapid antigen test.”

see: statnews.com/2022/01/05/stu…
Remember when I said “rapid antigen tests may be contributing to the spread of #Omicron
Read 4 tweets

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