5 ms·

This seems like a potentially game-changing discovery - if we could trivially diagnose 30%+ of cases, that could drastically diminish growth rate. Are there st

This seems like a potentially game-changing discovery - if we could trivially diagnose 30%+ of cases, that could drastically diminish growth rate. Are there standard anosmia tests? I'm wondering how to make this actionable in the most efficient way.

amelius 7y ago
I couldn't read the article, but of course the usefulness of this test also depends on the time of onset of the symptoms wrt the disease.
HaukeHi 7y ago
From ""Rapid Clinical Evaluation of Anosmia - The Alcohol Sniff Test" (https://jamanetwork.com/journals/jamaotolaryngology/article-abstract/624172 https://jamanetwork.com/journals/jamaotolaryngology/article-...):"Standard 70% isopropyl alcohol preparation pad is opened such that 0.5 cm of the pad itself is visible. The alcohol pad is placed beneath the patient's nostrils while the patient inspires twice, to familiarize himself or herself with the alcohol odor, and the subject is asked if he or she detects an odor. Odor thresholds for alcohols are 2 or more orders of magnitude lower than trigeminal thresholds for the same stimuli.6 Thus, an anosmic will detect the presence of alcohol trigeminally only when it is extremely close to the nose. The alcohol pad is withdrawn and the threshold test begun. The subject is asked to close the mouth and eyes, breathe normally, and indicate when the odor is detected. Active sniffing and deep inspiration are discouraged. The basic procedure follows the method of limits. A standard metric tape measure is extended downward from the patient's nares and held in place (Figure I ). The alcohol pad is placed 30 cm below the nose and, with each expiration, is moved 1 cm closer to the nares until the subject detects the presence of odor. The distance from the anterior nares to the alcohol padis measured in centimeters at the point at which the subject first detects the odor. The procedure is repeated 4 times and the mean distance defines the threshold.Butanol ThresholdFor purposes of comparison, all of the subjects completed a standard olfactory threshold test. A series of 10 concentrations of butanol ( -butyl alcohol) was used to determine absolute olfactory threshold sensitivity. The highest butanol concentration consisted of 4% vol/vol in distilled water. Each successive dilution was one third of the preceding dilution. Two "blanks," containing only distilled water, were also prepared. All bottles, including blanks, contained 60 mL of liquid. Olfactory threshold was assessed with a modified version7 of a 2-alternative, forced-choice,ascending method of limits procedure.8 The subject was presented with 2 bottles, one containing the odorant and the other consisting of distilled water. Each nostril was tested separately. The spout of the bottle was inserted into the nos tril of interest. The subject was asked to squeeze the bottleto generate a puff of air. The subject did this with both bottles. Subjects were asked to identify which of the 2 bottles contained the stronger odor.All subjects began at the lowest concentration to avoidadaptation.9 Incorrect choices led to presentation of a higher concentration and correct choices led to continued presentation of the same concentration to a criterion of 5 successive correct responses. The presentation of the odorantand blank were randomized for each comparison trial and the nostril to be tested first was also randomly determined. There were approximately 45 seconds between trials to allow time for recovery of the olfactory system and for the odor molecules to collect in the head space of the bottle." However, this test has been called imprecise (https://journals.sagepub.com/doi/abs/10.2500/ajra.2017.31.4403 https://journals.sagepub.com/doi/abs/10.2500/ajra.2017.31.44...). If the paper is true, one could do spot checks today to estimate the true IFR in every country tomorrow on a shoestring budget. https://www.statnews.com/2020/03/17/a-fiasco-in-the-making-as-the-coronavirus-pandemic-takes-hold-we-are-making-decisions-without-reliable-data/ https://www.statnews.com/2020/03/17/a-fiasco-in-the-making-a... Depending on the results that might save trillions of dollars.
- nomel 7y ago
  It seems this test would be extremely sensitive to air currents in the room, like an air vent anywhere near the person.
  - pbhjpbhj 7y ago
    Tell people not to test in an obvious draft? It would only be indicative on a population scale anyway, surely. Seems worth trying; an experiment that some of the millions of school kids at home could easily do once a week over the next 6 weeks or so. So, we need a data collection website?
jimnotgym 7y ago
Here is the problem. I'm suffering with what appears to be mild Covid-19 and I have experienced a mild loss of taste. Therefore it could be dismissed as 'just a cold' for people like me.
- meowface 7y ago
  By appears, do you mean "tested positive but symptoms appear to be mild so far", or do you mean you think you might have it but haven't been tested?
  - jimnotgym 7y ago
    They are not testing people in the UK unless they require a ventilator, so I have to guess like everyone else! I think I have it.
ltbarcly3 7y ago
The testing for Covid doesn't help anyone that has it, it helps all of us as a community. The health agencies need to know how many people have it and where to direct resources and understand if they need to increase (or are able to decrease) the restrictions to movements and gatherings. There is no special treatment yet available for Covid, so whether or not your doctor knows you have it won't change how they treat you.
- Marsymars 7y ago
  > The testing for Covid doesn't help anyone that has it It helps you a lot once you've recovered after you test positive.
  - ltbarcly3 7y ago
    How?
    - Marsymars 7y ago
      Then you know you've had covid-19 already, are immune to it, and can't pass it on to others. (For the short to medium term, at least.)
75dvtwin 7y ago
30% is a big number. Reducing number of silient carriers would be great. I am also wondering if, in general, our societies would benefit from a periodic self-quarantine, as a prophylactic measure. I guess, if, after this pandemic is over -- we see fewer cases of H1N1 and other upper-respiratory transmittable viruses -- we could conclude that periodic, world-wide self quarantine should be written into laws of public health. May be every 5 years or so, for 1.5 months stop all non-essential travel, work commute, public gatherings and so on. Do not know if the above idea has any historical precedent, but, clearly our world has developed into very inter-connected, redundant, essentially unbreakable pathogen re-transmission network. So we need to respond to this.
- bawolff 7y ago
  I doubt it would stop the flu, etc. Maybe slow it down for a little bit, but well there are different strains of flu every year, it stands to reason that every year it starts from just a small group and rapidly spreads. I think the effect on the flu will be negligable shortly after quarintine ends.* *IANA-person who knows about this subject.
  - 75dvtwin 7y ago
    with the institutionalized, periodic prophylactic quarantine -- I was thinking, we could break/slowdown the pathogen re-transmission network (at least temporary). I was thinking that the above realization, could come as outcome of 'what could be done better' analysis, at the end of this pandemic.
  - quintushoratius 7y ago
    Supposedly, the February break that New England school districts follow was designed to stop the flu. Take everyone out of school for a week to stop the spread, hope that everyone that shows symptoms by the end of the week stays home. Of course, that doesn't work when kids still go to school when sick, which they do. When I was a kid the school used to give awards to kids with perfect attendance. Now February break seems to be an annoyance for most parents and they find daycare alternatives, as well as sending marginal (or even outright sick!) children to school.
binyomin 7y ago
My sense of smell is 100% gone as this is written One needs no formal test it is blatantly obvious when the smell is gone

amelius 7y ago

I couldn't read the article, but of course the usefulness of this test also depends on the time of onset of the symptoms wrt the disease.

HaukeHi 7y ago

From ""Rapid Clinical Evaluation of Anosmia - The Alcohol Sniff Test" (https://jamanetwork.com/journals/jamaotolaryngology/article-abstract/624172 https://jamanetwork.com/journals/jamaotolaryngology/article-...):"Standard 70% isopropyl alcohol preparation pad is opened such that 0.5 cm of the pad itself is visible. The alcohol pad is placed beneath the patient's nostrils while the patient inspires twice, to familiarize himself or herself with the alcohol odor, and the subject is asked if he or she detects an odor. Odor thresholds for alcohols are 2 or more orders of magnitude lower than trigeminal thresholds for the same stimuli.6 Thus, an anosmic will detect the presence of alcohol trigeminally only when it is extremely close to the nose. The alcohol pad is withdrawn and the threshold test begun. The subject is asked to close the mouth and eyes, breathe normally, and indicate when the odor is detected. Active sniffing and deep inspiration are discouraged. The basic procedure follows the method of limits. A standard metric tape measure is extended downward from the patient's nares and held in place (Figure I ). The alcohol pad is placed 30 cm below the nose and, with each expiration, is moved 1 cm closer to the nares until the subject detects the presence of odor. The distance from the anterior nares to the alcohol padis measured in centimeters at the point at which the subject first detects the odor. The procedure is repeated 4 times and the mean distance defines the threshold.Butanol ThresholdFor purposes of comparison, all of the subjects completed a standard olfactory threshold test. A series of 10 concentrations of butanol ( -butyl alcohol) was used to determine absolute olfactory threshold sensitivity. The highest butanol concentration consisted of 4% vol/vol in distilled water. Each successive dilution was one third of the preceding dilution. Two "blanks," containing only distilled water, were also prepared. All bottles, including blanks, contained 60 mL of liquid. Olfactory threshold was assessed with a modified version7 of a 2-alternative, forced-choice,ascending method of limits procedure.8 The subject was presented with 2 bottles, one containing the odorant and the other consisting of distilled water. Each nostril was tested separately. The spout of the bottle was inserted into the nos tril of interest. The subject was asked to squeeze the bottleto generate a puff of air. The subject did this with both bottles. Subjects were asked to identify which of the 2 bottles contained the stronger odor.All subjects began at the lowest concentration to avoidadaptation.9 Incorrect choices led to presentation of a higher concentration and correct choices led to continued presentation of the same concentration to a criterion of 5 successive correct responses. The presentation of the odorantand blank were randomized for each comparison trial and the nostril to be tested first was also randomly determined. There were approximately 45 seconds between trials to allow time for recovery of the olfactory system and for the odor molecules to collect in the head space of the bottle." However, this test has been called imprecise (https://journals.sagepub.com/doi/abs/10.2500/ajra.2017.31.4403 https://journals.sagepub.com/doi/abs/10.2500/ajra.2017.31.44...). If the paper is true, one could do spot checks today to estimate the true IFR in every country tomorrow on a shoestring budget. https://www.statnews.com/2020/03/17/a-fiasco-in-the-making-as-the-coronavirus-pandemic-takes-hold-we-are-making-decisions-without-reliable-data/ https://www.statnews.com/2020/03/17/a-fiasco-in-the-making-a... Depending on the results that might save trillions of dollars.

nomel 7y ago
It seems this test would be extremely sensitive to air currents in the room, like an air vent anywhere near the person.
- pbhjpbhj 7y ago
  Tell people not to test in an obvious draft? It would only be indicative on a population scale anyway, surely. Seems worth trying; an experiment that some of the millions of school kids at home could easily do once a week over the next 6 weeks or so. So, we need a data collection website?

jimnotgym 7y ago

Here is the problem. I'm suffering with what appears to be mild Covid-19 and I have experienced a mild loss of taste. Therefore it could be dismissed as 'just a cold' for people like me.

meowface 7y ago
By appears, do you mean "tested positive but symptoms appear to be mild so far", or do you mean you think you might have it but haven't been tested?
- jimnotgym 7y ago
  They are not testing people in the UK unless they require a ventilator, so I have to guess like everyone else! I think I have it.

ltbarcly3 7y ago

The testing for Covid doesn't help anyone that has it, it helps all of us as a community. The health agencies need to know how many people have it and where to direct resources and understand if they need to increase (or are able to decrease) the restrictions to movements and gatherings. There is no special treatment yet available for Covid, so whether or not your doctor knows you have it won't change how they treat you.

Marsymars 7y ago
> The testing for Covid doesn't help anyone that has it It helps you a lot once you've recovered after you test positive.
- ltbarcly3 7y ago
  How?
  - Marsymars 7y ago
    Then you know you've had covid-19 already, are immune to it, and can't pass it on to others. (For the short to medium term, at least.)

75dvtwin 7y ago

30% is a big number. Reducing number of silient carriers would be great. I am also wondering if, in general, our societies would benefit from a periodic self-quarantine, as a prophylactic measure. I guess, if, after this pandemic is over -- we see fewer cases of H1N1 and other upper-respiratory transmittable viruses -- we could conclude that periodic, world-wide self quarantine should be written into laws of public health. May be every 5 years or so, for 1.5 months stop all non-essential travel, work commute, public gatherings and so on. Do not know if the above idea has any historical precedent, but, clearly our world has developed into very inter-connected, redundant, essentially unbreakable pathogen re-transmission network. So we need to respond to this.

bawolff 7y ago
I doubt it would stop the flu, etc. Maybe slow it down for a little bit, but well there are different strains of flu every year, it stands to reason that every year it starts from just a small group and rapidly spreads. I think the effect on the flu will be negligable shortly after quarintine ends.* *IANA-person who knows about this subject.
- 75dvtwin 7y ago
  with the institutionalized, periodic prophylactic quarantine -- I was thinking, we could break/slowdown the pathogen re-transmission network (at least temporary). I was thinking that the above realization, could come as outcome of 'what could be done better' analysis, at the end of this pandemic.
- quintushoratius 7y ago
  Supposedly, the February break that New England school districts follow was designed to stop the flu. Take everyone out of school for a week to stop the spread, hope that everyone that shows symptoms by the end of the week stays home. Of course, that doesn't work when kids still go to school when sick, which they do. When I was a kid the school used to give awards to kids with perfect attendance. Now February break seems to be an annoyance for most parents and they find daycare alternatives, as well as sending marginal (or even outright sick!) children to school.

binyomin 7y ago

My sense of smell is 100% gone as this is written One needs no formal test it is blatantly obvious when the smell is gone