Peter Peumans

Why not?

[Peter Peumans @petepeumans]

@JMRothberg More info on how aerosol/PCR is done here: https://t.co/EFFQxTtwg6

[Peter Peumans @petepeumans]

@JMRothberg FYI, we're also seeing interesting things happen with some omicron-infected subjects. For example, this subject is consistently negative on Ag and mostly negative on NP-swab/PCR. Presumably, this subject is still infectious because aerosol/PCR is positive. Working on more data.

[Peter Peumans @petepeumans]

@EricTopol @CDCgov @substack Yet, in our recent study we noticed subjects continue to test positive on rapid antigen tests while no longer exhaling detectable amounts of virus. I would argue that exhaled viral load is what we should be concerned about. https://t.co/f5PHFAe53b

[Peter Peumans @petepeumans]

@DCDoc33 The only way to make sure is to start measuring exhaled virus: https://t.co/f5PHFAe53b. Ideally using culture, but exhaled viral load is a start.

[Peter Peumans @petepeumans]

@Don_Milton @EricTopol @Bob_Wachter @kprather88 @linseymarr @RickABright @CathNoakes We’re seeing similar viral loads in omicron-infected subjects but using a 1 min breath sample using this approach: https://t.co/LpDd55nsom. We believe most infected will exhale 100-10,000 virions/minute early in the infection and when vocalizing!

[Peter Peumans @petepeumans]

@soupvector @ashishkjha I would agree. We study exhaled viral load, and we're seeing some infected subjects exhaling over 100 times as much virus as typical. More work needed, but I think there's a good chance these prolific viral shedders can infect others even outdoors. Depends on the details. Masks!

[Peter Peumans @petepeumans]

@BillHanage @alanmcn1 Pointing out that there is a marked difference between swab and exhaled viral load (which we assume is a measure of contagiousness, albeit imperfect). This has impact on how to use rapid antigen tests. https://t.co/o8Av4veRvK

[Peter Peumans @petepeumans]

@Bob_Wachter Our recent work suggests that during the first two days of detectable viral load in swabs, you exhale peak amounts of virus, while rapid antigen tests will not yet be reliably positive. Different viral load dynamics in breath vs swab. https://t.co/o8Av4veRvK

[Peter Peumans @petepeumans]

@soupvector @imec_int The appreciation is mutual! Re-iterating that we don't mean to say rapid antigen tests aren't useful. They are a fantastic instrument. Understanding viral load dynamics in swabs and breath will help optimal use from a public health perspective. @michaelmina_lab

[Peter Peumans @petepeumans]

@DataDrivenMD To get the maximum out of a rapid Ag test (when visiting someone immunocompromised or unvaccinated) best to limit exposure as much as possible in the 3-4 days leading up to the gathering. This allows an infection to reveal itself in your swab viral load. Then test right before.

[Peter Peumans @petepeumans]

@DataDrivenMD While rapid antigen tests aren't perfect, they are still very useful. Hey, they are available (mostly)! Being aware of their shortcomings means we can get more value out of them and save lives.

[Peter Peumans @petepeumans]

@linseymarr FYI, we see 10-100 genome copies per liter exhaled air or about 10k-100k gc per m3 exhaled. This is measured using a dedicated aerosol sampling device. https://t.co/PsbEy5mQJ4

[imec @imec_int]

#pressrelease Infected people spread Covid particles via exhaled breath in early stages of their infection, while their rapid antigen test is negative according to clinical study by imec, @UZLeuven and @KU_Leuven
https://t.co/OSXfzUkrKJ

@petepeumans @Emmanuel_microb

[Peter Peumans @petepeumans]

@EricTopol @TheLancet We think these graphs need an additional component: exhaled viral load as a proxy for infectiousness https://t.co/PsbEy5mQJ4

[imec @imec_int]

#pressrelease Infected people spread Covid particles via exhaled breath in early stages of their infection, while their rapid antigen test is negative according to clinical study by imec, @UZLeuven and @KU_Leuven
https://t.co/OSXfzUkrKJ

@petepeumans @Emmanuel_microb

[Peter Peumans @petepeumans]

@Enrique_Acevedo @FinancialTimes We think this update is more accurate given what we've learned about exhaled viral load https://t.co/PsbEy5mQJ4

[imec @imec_int]

#pressrelease Infected people spread Covid particles via exhaled breath in early stages of their infection, while their rapid antigen test is negative according to clinical study by imec, @UZLeuven and @KU_Leuven
https://t.co/OSXfzUkrKJ

@petepeumans @Emmanuel_microb

[Peter Peumans @petepeumans]

@meeussjes @povnuffel @Emmanuel_microb Ik kan me inbeelden dat je de kans op een vals negatief resultaat kan verkleinen door meerdere plekken te samplen. Allicht weet @Emmanuel_microb meer.

[Peter Peumans @petepeumans]

@DataDrivenMD I think it's important we don't undermine rapid antigen tests, because they are a powerful tool to prevent infection given their time-to-result and availability. We just need to be aware of the shortcomings and act accordingly.

[Peter Peumans @petepeumans]

@DataDrivenMD To get the maximum out of a rapid Ag test (when visiting someone immunocompromised or unvaccinated) best to limit exposure as much as possible in the 3-4 days leading up to the gathering. This allows an infection to reveal itself in your swab viral load. Then test right before.

[Peter Peumans @petepeumans]

@DataDrivenMD @EricTopol @SherylNYT The main point we wanted to make is that there is a marked difference in the dynamics of swab vs exhaled viral load. Assuming the latter is a proxy for infectiousness. Could lead to better use of antigen tests. Not perfect but it's the best we have at this time.

[Peter Peumans @petepeumans]

@ScottGottliebMD In addition, we need to start looking at exhaled viral load https://t.co/PsbEy5mQJ4

[imec @imec_int]

#pressrelease Infected people spread Covid particles via exhaled breath in early stages of their infection, while their rapid antigen test is negative according to clinical study by imec, @UZLeuven and @KU_Leuven
https://t.co/OSXfzUkrKJ

@petepeumans @Emmanuel_microb

[Peter Peumans @petepeumans]

@firefoxx66 To get the maximum out of a rapid Ag test (when visiting someone immunocompromised or unvaccinated) best to limit exposure as much as possible in the 3-4 days leading up to the gathering. This allows an infection to reveal itself in your swab viral load. Then test right before.

[Peter Peumans @petepeumans]

@firefoxx66 Some additional advice on LFTs from this study https://t.co/PsbEy5mQJ4

[imec @imec_int]

#pressrelease Infected people spread Covid particles via exhaled breath in early stages of their infection, while their rapid antigen test is negative according to clinical study by imec, @UZLeuven and @KU_Leuven
https://t.co/OSXfzUkrKJ

@petepeumans @Emmanuel_microb