There's No Point to Temperature Checks for Cruising - They are Useless

[donaldsc]

Everyone everywhere (ships, airports, entering building, etc) is counting on temperature checks to check to see if a person is ill with Covid.  Turns out that the temperature checks are just theater and are totally useless.

 

Here is an article that I found on the WEB titled What is the Point of Temperature Checks  documenting the uselessness of temperature checks - https://slate.com/technology/2020/05/temperature-checks-coronavirus.html?sid=5388d0e4dd52b8417a00b1f7&utm_medium=email&utm_source=newsletter&utm_content=TheSlatest&utm_campaign=traffic.   

 

This is  a quote from the article which references an JAMA paper that says that 30% of 5700 patients hospitalized for Covid and known to have it do not have an elevated temperature

 

"Temperature checks would miss anyone who does not have symptoms or, in particular, this symptom. Exactly how often a coronavirus infection comes with a fever is still slightly unclear, but what is certain is that it is possible to be sick with COVID-19 and not have a fever. It’s even more likely that you wouldn’t have a fever for the duration of the infection. A case study of 5,700 patients hospitalized for COVID-19 in the New York City area published in JAMA found that just over 30 percent of patients had a fever when they came in, which caused experts to question the utility of temperature checks at all."

 

I looked up the JAMA paper and this is a reference to the original paper -  https://jamanetwork.com/journals/jama/fullarticle/2765184.  It is long and a bit technical but appears to be a well designed study as it was set up to use original data designed for the study and is not a rehash of older hospital records.  A population size of 5700 patients is also a good population.  You need to open up the table tab on the right and look at Table 2.  I have copied Table 2 to this post.  Note line 2 of the paper that shows that only 30.7% of new patients admitted to hospital w Covid had an elevated temperature.  That means that 70% of the patients with Covid tested as a false negative if the temperature tests was to be used to determine if the patient has Covid.  I would say that a test w a 70% false negative test is sort of useless and is just theater.

 

DON

 

Edited May 22, 2020 by donaldsc

[spookwife]

I was just at my doctors office.  Got temp checked coming into the building. 96.8. The gun thingy

 

10 minutes later, 99.6 with a traditional thermometer Under the tongue.  
 

 

[chengkp75]

5 hours ago, spookwife said:

I was just at my doctors office.  Got temp checked coming into the building. 96.8. The gun thingy

 

10 minutes later, 99.6 with a traditional thermometer Under the tongue.  
 

 

We use one at the gangway of our ship, but it comes with significant limitations in the usage instructions.  Changes in environmental temperature (even a person holding the unit for a long period) can affect the readings.  Exercise can affect the reading.  Perspiration can affect the reading.  If the person has changed environment within a few minutes (gone from outside to air conditioning) it can affect readings.  Lots of studies show that the forehead temperature scan is the least accurate, and that if a surface scan is desired, it should be done behind the ear.

[navybankerteacher]

59 minutes ago, chengkp75 said:

We use one at the gangway of our ship, but it comes with significant limitations in the usage instructions.  Changes in environmental temperature (even a person holding the unit for a long period) can affect the readings.  Exercise can affect the reading.  Perspiration can affect the reading.  If the person has changed environment within a few minutes (gone from outside to air conditioning) it can affect readings.  Lots of studies show that the forehead temperature scan is the least accurate, and that if a surface scan is desired, it should be done behind the ear.

I hope it does not come to having to check temperature the old fashioned way.

[ATC cruiser]

6 minutes ago, navybankerteacher said:

I hope it does not come to having to check temperature the old fashioned way.

😱

[John Bull]

OK, so it finds only 30%.

But it's quick and easy, needs only basic training for any employee with half a brain to operate, and there's no mention of false positives (thus no unnecessary refused entry / quarantining, etc)

 

So because it finds only 30%, is that not better than finding none at all ??

Or would you suggest that for instance everyone should have been held at an airport for 48 hours or probably longer waiting for  results of laboratory tests?

 

I stepped off an airplane into 30+ degrees C in Tanzania, & was held in a line outside the airport building in direct sun for 20+ minutes, feeling very hot & bothered & the sweat was running into my eyes. When I reached the guy with the gun. I told him I was very very hot. He looked at the gun & said "no, you're not" (I thought "ahh, that's what my partner keeps telling me ) so certainly in my case perspiration didn't show a false positive.

 

No doubt in due course there will be quick-and-easy tests for everyone, but as a stop-gap I don't see temperature-checking as useless and certainly not just theatre.

 

JB 

[Joebucks]

7 hours ago, donaldsc said:

just theater and are totally useless.

 

Welcome to 2020 and how everything works

[cruisemom42]

As JB suggests, we should be careful about calling something "useless" if it can detect the 30% with fever. Additionally, we don't know whether the patients in the JAMA study (e.g., those being admitted to the hospital) mirror those who are walking around, presumably in earlier stages of infection and potentially more likely to have a fever.

 

That said, the temp reading is at best one tool that can help. It is not a silver bullet. Testing would be much better -- the JAMA study noted that for this same group of patients, the first test for COVID-19 was positive in 96.8%.  

 

Why aren't we pursuing more and better testing?

Edited May 22, 2020 by cruisemom42

[DarrenM]

33 minutes ago, navybankerteacher said:

I hope it does not come to having to check temperature the old fashioned way.

Why not?

 

Leaves very quickly.

[DarrenM]

Testing? Unless testing can be done and analysed immediately whas the point?

 

You get a test on monday. 

 

You get the result on Wednesday. All clear.

 

In between you contract the virus on the Tuesday.

 

That worked well.

 

And isnt there a 4-5 day period where symptoms dont show?

[sanger727]

I agree that the temperature testing is more of a window dressing than an actual safety measure. We do temperature testing at work. Our policy is that if you feel sick, you should stay home. If you show up and have a fever you get sent home. What I'm not sure about is the number of people that feel completely healthy AND have a fever? Don't most people with a fever also feel unwell? If you are feeling unwell you should stay home, not come and and potentially contaminate everything and everyone until you get your temperature checked and it shows you have a fever. So, if you are staying home when you are sick (like you are supposed to) the fever thing is relatively meaningless because you won't show up anywhere to get your temperature checked. If you are asymptomatic or don't have typical COVID symptoms the temperature check won't catch you because you still won't have a fever. 

 

As a side note we checking the fever of 1,000+ people daily and have been doing it since mid April. I am the person in charge of cataloging all of the data we accumulate doing this. I don't know of a single instance of a person feeling well enough to come to work and being found to have a fever (so the temperature check actually serving it's designed purpose). 

 

Now, that being said, I think cruise lines and airports will have to do temperature checks  because it is something they can do to say they do them. And also because when that long awaited vacation is on the line, I don't trust people who are sick to stay home.

Edited May 22, 2020 by sanger727

[2wheelin]

23 minutes ago, sanger727 said:

 

 

As a side note we checking the fever of 1,000+ people daily and have been doing it since mid April. I am the person in charge of cataloging all of the data we accumulate doing this. I don't know of a single instance of a person feeling well enough to come to work and being found to have a fever (so the temperature check actually serving it's designed purpose). 

 

Now, that being said, I think cruise lines and airports will have to do temperature checks  because it is something they can do to say they do them. And also because when that long awaited vacation is on the line, I don't trust people who are sick to stay home.

That is the main reason to check. Because people will know they can be caught. It’s a very simple screening to do.

If it is good enough for most major medical institutions around the world, I would not put too much weight on one irrelevant study. I say irrelevant because it only tested hospitalized, positive patients. The study only tells us that 70% of Covid patients do not have an elevated temp after hospitalization.

[Markanddonna]

I'm a case study on the limitations of temperature checks. My normal temp is 96.8, and if I was a horrible person and wanted to get onboard, I could take a temperature reducing drug if I had a fever.  So, my 101 degree temp could probably be reduced to 99 degrees which everyone would consider normal. In reality, that translates into a 103 degrees fever for the average population..  

[ColeThornton]

Edited.  Nevermind.

Edited May 22, 2020 by ColeThornton

[sanger727]

1 hour ago, 2wheelin said:

That is the main reason to check. Because people will know they can be caught. It’s a very simple screening to do.

If it is good enough for most major medical institutions around the world, I would not put too much weight on one irrelevant study. I say irrelevant because it only tested hospitalized, positive patients. The study only tells us that 70% of Covid patients do not have an elevated temp after hospitalization.

 

I'm sure the study has limited benefit. But I also think temperature checks are not the silver bullet people seem to think they are. You can't check the temperature of everyone boarding a cruise ship or plane and equate that to mean that no one on the cruise or the plane has COVID. While I have read repeatedly that fever is a common symptom, I'm sure it's not present for everyone. It doesn't capture people that are pre-symptomatic or asymptomatic or have had the illness long enough that they no longer have a fever but are still infectious. I wouldn't go as far as saying they are useless, but I also don't think they are incredibly useful.

[navybankerteacher]

58 minutes ago, cruisemom42 said:

As JB suggests, we should be careful about calling something "useless" if it can detect the 30% with fever. Additionally, we don't know whether the patients in the JAMA study (e.g., those being admitted to the hospital) mirror those who are walking around, presumably in earlier stages of infection and potentially more likely to have a fever.

 

That said, the temp reading is at best one tool that can help. It is not a silver bullet. Testing would be much better -- the JAMA study noted that for this same group of patients, the first test for COVID-19 was positive in 96.8%.  

 

Why aren't we pursuing more and better testing?

Significant.

 

It is easy, and perhaps tempting, to write something off if it less than 50% effective.   There are probably flaws in everything:  washing your hands frequently might not keep you safe,  face masks might help others but only have a very small positive result for the wearer (of course if everyone wears one - YOU are an “other” who is helped), social distancing might not always protect you — but taken all together they surely do improve your odds.

[LH25]

2 hours ago, sanger727 said:

What I'm not sure about is the number of people that feel completely healthy AND have a fever? Don't most people with a fever also feel unwell? If you are feeling unwell you should stay home, not come and and potentially contaminate everything and everyone until you get your temperature checked and it shows you have a fever.

My husband and I both have co-workers who have come to work sick.  They insist they feel fine, and that it's just allergies.  One found out later they had strep throat and had been at work.  Even when we had other co-workers who were undergoing medical treatments that lowered their immunity, one came in sick.

 

The odd thing is that these are generally nice people in other ways.

[John Bull]

2 hours ago, sanger727 said:

. So, if you are staying home when you are sick (like you are supposed to) the fever thing is relatively meaningless because you won't show up anywhere to get your temperature checked.

 

 

That's the krunch with air-travel & cruising.

Not a lot different to folk feeling the onset of norovirus.

"I've spent a fortune of flights & cruise (or I need to get back home from foreign lands), so I'm not going to admit to feeling unwell"

Understandable but incredibly selfish.

And any means of preventing those folk from mixing & spreading, no matter how limited those means, should be used.

 

BTW - a swab test which gives a result in 20 minutes, without the need for laboratory analysis and with a very high accuracy level is currently being trialed in the UK. And didn't I see, several weeks ago, a video of a similar test with equally quick results - in the USA, the guy drove through a test centre & was given the all-clear. (IIRC he should have booked on-line, but chanced his arm & wasn't challenged about a booking when he showed up).

 

JB 

Edited May 22, 2020 by John Bull

[sanger727]

11 minutes ago, LH25 said:

My husband and I both have co-workers who have come to work sick.  They insist they feel fine, and that it's just allergies.  One found out later they had strep throat and had been at work.  Even when we had other co-workers who were undergoing medical treatments that lowered their immunity, one came in sick.

 

The odd thing is that these are generally nice people in other ways.

 

I always have trouble believing this claim. I came down with allergies for the first time a few years ago. And I did legitimately think I was sick because I had never had allergies so didn't consider it as a possibility. Now that I have them and know how to manage them, I have no issues recognizing the difference between allergies and being sick. 

 

Late last year (prior to any of this COVID business) I had a co-worker come in sick. He went to employee health services and they test him for the flu. He tested negative and kept coming to work and said "the doctor said it's not a flu, just a virus, so its ok" SMH. We kept our distance from him. 

 

Post COVID I would hope this wouldn't happen. 

[donaldsc]

2 hours ago, 2wheelin said:

That is the main reason to check. Because people will know they can be caught. It’s a very simple screening to do.

If it is good enough for most major medical institutions around the world, I would not put too much weight on one irrelevant study. I say irrelevant because it only tested hospitalized, positive patients. The study only tells us that 70% of Covid patients do not have an elevated temp after hospitalization.

 

That tells us that using temperature to determine if people have Covid and that is what the cruise companies and everyone else is planning to do will miss 70% of the people, who do have Covid.  In other words, it will miss more people with Covid than it will find.  I still say that the this means that the test is useless and just theater.  WE all know that the reason that everyone uses the temperature check is that it is cheap, fast and gives instantaneous results.  Bad results but cheap and fast.

 

I read the paper and it appears to be a good one in terms of its purpose which was to determine what parameters 7000 patients with Covid had when they were admitted to the hospital.  

 

One more thing.  Would you call the Mayo Clinic a major medical institution.  I was just there for 4 days for tests.  They require a nasal swab test administered by them before you can go into any of their facilities.  The test is good for only 3 days and because I was there for 4 days, I had to get a 2nd test.  Both were negative.  

 

DON

[ilikeanswers]

1 hour ago, sanger727 said:

Late last year (prior to any of this COVID business) I had a co-worker come in sick. He went to employee health services and they test him for the flu. He tested negative and kept coming to work and said "the doctor said it's not a flu, just a virus, so its ok" SMH. We kept our distance from him. 

 

Post COVID I would hope this wouldn't happen. 

 

Some people fear they might lose their job or promotion opportunities for taking a sick day or are in employment that does not offer sick pay and can't afford to miss a pay check. Taking a sick day isn't always an option for everyone.

[donaldsc]

51 minutes ago, donaldsc said:

 

That tells us that using temperature to determine if people have Covid and that is what the cruise companies and everyone else is planning to do will miss 70% of the people, who do have Covid.  In other words, it will miss more people with Covid than it will find.  I still say that the this means that the test is useless and just theater.  WE all know that the reason that everyone uses the temperature check is that it is cheap, fast and gives instantaneous results.  Bad results but cheap and fast.

 

I read the paper and it appears to be a good one in terms of its purpose which was to determine what parameters 7000 patients with Covid had when they were admitted to the hospital.  

 

One more thing.  Would you call the Mayo Clinic a major medical institution.  I was just there for 4 days for tests.  They require a nasal swab test administered by them before you can go into any of their facilities.  The test is good for only 3 days and because I was there for 4 days, I had to get a 2nd test.  Both were negative.  

 

DON

 

Another thing that I forgot to say.  If the temperature check missed 70% of the patients who had symptoms that were bad enough to warrant a hospital admission, what percentage of people who were asymptomatic or had symptoms that were not bad enough to go to the hospital would have been missed.  Want to bet that the false negative rate for that group was higher than 70%.  We will never know until they do a special study to find it out and we all know that this special study will never be done.  As someone previously responded, this study was not designed to determine how many false positives the test will have where a person has an elevated temperature but does not have Covid.

 

With a disease such as Covid, false negatives are far worse than false positive.  A false negative means that people are walking around infecting other people and they don't know it.  With a false positive, a person will be subjected to a better confirming test and determined not have the disease so nobody is hurt.

 

 

DON

Edited May 22, 2020 by donaldsc

[HxFx]

There are other contagious illnesses that temperature screening could prevent getting on board as well. Even if it’s only a reduction of the number with contagious diseases, that would help. Particularly those illnesses that require a high viral load. 

[cruisemom42]

4 hours ago, sanger727 said:

Our policy is that if you feel sick, you should stay home. If you show up and have a fever you get sent home. What I'm not sure about is the number of people that feel completely healthy AND have a fever? Don't most people with a fever also feel unwell? If you are feeling unwell you should stay home, not come and and potentially contaminate everything and everyone until you get your temperature checked and it shows you have a fever. So, if you are staying home when you are sick (like you are supposed to) the fever thing is relatively meaningless because you won't show up anywhere to get your temperature checked.

 

I refer you to the excellent points made in post #21.

 

Especially in the US, employers are generally stingy with sick leave. Companies tend to give a paltry few days for the entire year -- in my company it used to be 5, out of which one also had to take any regular check-ups, visits to the doctor or dentist, etc. Or they give employees one bucket for all paid time off (PTO), out of which employees then have to manage any vacation time, sick time, and other reasons why one may not be able to be at work including family care.

 

If employers were more forthcoming about allowing paid time off whenever the employee is sick, or at least for COVID-related illness in the immediate period, I feel more people would stay at home because they would not have the "pressure" to come to work.

 

 

[evandbob]

How effective were the health questionaires some lines required prior to boarding?  There is no method available today that will be 100% effective.  So we go through the motions and it will make some people satisfied and others (like me) cynical.