COVID-19 Testing: How are the data calculated?

Posted by tjdog @tjdog, Jun 30, 2020

I’m hearing that if a person tests positive for Covid-19, then is tested again in a couple of days and tests positive again, it’s reported In the statistics as 2 positive tests. Each subsequent positive test for that same person is counted again, even though this person did not test negative between tests. Does anyone know if this is true?

Interested in more discussions like this? Go to the Post-COVID Recovery & COVID-19 Support Group.

@tjdog, There are so many reports out about all things to do with testing that it can be tricky to decide whom to believe. I just use reported cases as a guide and reminder to myself to continue taking precautions so that I won't need that initial test. Have you been tested or are you like me, curious about many things and just wondering? Stay safe and well. Best

REPLY

I haven’t been tested. I’m asking because neighbors are using this to conclude that the number of cases is exaggerated. Therefore, they don’t need to take precautions, as you and I do. I like to give them facts to dispute their statements, but I can’t find anything on this.

REPLY
@tjdog

I haven’t been tested. I’m asking because neighbors are using this to conclude that the number of cases is exaggerated. Therefore, they don’t need to take precautions, as you and I do. I like to give them facts to dispute their statements, but I can’t find anything on this.

Jump to this post

@tjdog- It's very confusing and dangerous for anyone to think that COVID-19 is something to take lightly. I found that it's very difficult to talk to people who think that new cases are a hoax, or are being exaggerated. My answer is that wear masks greatly reduced the incidence of COVID-19 as it protects others, along with washing your hands and social distancing in case you are ill. It shows respect for others until history shows us otherwise.

REPLY

@tjdog, You are correct. A person may have multiple positive tests, but they should be calculated as a single positive case. The number of positive tests in a state is not equal to the number of cases, as one person may be tested more than once. It would appear that the people you are talking with are confusing the terms "test" vs. "case."
See this information:
- CDC https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/testing-in-us.html

There are certainly limitations to the data being collected and it varies from state to state. Rather than an over-calculation of cases, it is more likely than there are more cases than are being reported since not everyone is symptomatic and not everyone is getting tested.

From Johns Hopkins
"Since confirmed case numbers may be dependent on how much testing a state is doing, it is also important to see how many tests have occurred in each state. If people who are infected cannot get tested, they will not be counted as a confirmed case in the state’s data."

"When states report the number of COVID-19 tests performed, this should include the number of viral tests performed and the number of patients for which these tests were performed. Currently, states may not be distinguishing overall tests administered from the number of individuals who have been tested. This is an important limitation to the data that is available to track testing in the U.S., and states should work to address it."
https://coronavirus.jhu.edu/testing/testing-faq/overview#why-are-there-inconsistencies-among-testing-data-for-covid-19

Ideally, each state should be calculating tests vs. cases as this graph from Johns Hopkins shows:
https://coronavirus.jhu.edu/testing/states-comparison

REPLY

@tjdog I recently asked this question of my provider because I was given both a rapid test and a nasal swab - one person, 2 tests. Her reply was - our lab counts the number of unique patients (cases) tested. She went on to explain that if (in MN) you are tested at different times, through different labs, and do not report that you were already tested in another location, you may be counted twice - especially if negative. But if positive, and you are in the system already as positive, you will not be counted again, although they are beginning to maintain a database of people who test positive, then negative, and later positive again (very rare.)

Also (in MN) positive results are tracked by city/county of residence, not location of test site. This did not always happen early on, but is the norm now.

If you test in multiple states, all bets are off - as far as I know there is no national registry at this point.
As with everything Covid, stay tuned for further developments - this is a work in progress, and changes often.
Sue

REPLY
@colleenyoung

@tjdog, You are correct. A person may have multiple positive tests, but they should be calculated as a single positive case. The number of positive tests in a state is not equal to the number of cases, as one person may be tested more than once. It would appear that the people you are talking with are confusing the terms "test" vs. "case."
See this information:
- CDC https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/testing-in-us.html

There are certainly limitations to the data being collected and it varies from state to state. Rather than an over-calculation of cases, it is more likely than there are more cases than are being reported since not everyone is symptomatic and not everyone is getting tested.

From Johns Hopkins
"Since confirmed case numbers may be dependent on how much testing a state is doing, it is also important to see how many tests have occurred in each state. If people who are infected cannot get tested, they will not be counted as a confirmed case in the state’s data."

"When states report the number of COVID-19 tests performed, this should include the number of viral tests performed and the number of patients for which these tests were performed. Currently, states may not be distinguishing overall tests administered from the number of individuals who have been tested. This is an important limitation to the data that is available to track testing in the U.S., and states should work to address it."
https://coronavirus.jhu.edu/testing/testing-faq/overview#why-are-there-inconsistencies-among-testing-data-for-covid-19

Ideally, each state should be calculating tests vs. cases as this graph from Johns Hopkins shows:
https://coronavirus.jhu.edu/testing/states-comparison

Jump to this post

@colleenyoung Today on T. V. there was a report by a science about a new airology it has to do with which mask is better and said that with more material within the mask the better also tight fit around nose side of check and under chin . They showed the spray from different mask and the particles from these type of mask was the lowest spread factor . So more cloth in the mask seems to be the best . Do you have anything on this?

REPLY
@merpreb

@tjdog- It's very confusing and dangerous for anyone to think that COVID-19 is something to take lightly. I found that it's very difficult to talk to people who think that new cases are a hoax, or are being exaggerated. My answer is that wear masks greatly reduced the incidence of COVID-19 as it protects others, along with washing your hands and social distancing in case you are ill. It shows respect for others until history shows us otherwise.

Jump to this post

@merpreb @tjdog I came from Hong Kong, population about 7 and a half millions. Confirmed death from Covid is 6. They went through SARS, so when covid hits, they knew what is necessary. The compliance rate for face mask is 97%, unfortunately, the other 3% who did not comply are mostly Caucasians. It's hard to believe that some people don't want to take this seriously. That's why we are not seeing a leveling. It's very frustrating. I think some cities are opening up too soon. My county is on the watch list, case number going up and up each day.

REPLY
@colleenyoung

@tjdog, You are correct. A person may have multiple positive tests, but they should be calculated as a single positive case. The number of positive tests in a state is not equal to the number of cases, as one person may be tested more than once. It would appear that the people you are talking with are confusing the terms "test" vs. "case."
See this information:
- CDC https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/testing-in-us.html

There are certainly limitations to the data being collected and it varies from state to state. Rather than an over-calculation of cases, it is more likely than there are more cases than are being reported since not everyone is symptomatic and not everyone is getting tested.

From Johns Hopkins
"Since confirmed case numbers may be dependent on how much testing a state is doing, it is also important to see how many tests have occurred in each state. If people who are infected cannot get tested, they will not be counted as a confirmed case in the state’s data."

"When states report the number of COVID-19 tests performed, this should include the number of viral tests performed and the number of patients for which these tests were performed. Currently, states may not be distinguishing overall tests administered from the number of individuals who have been tested. This is an important limitation to the data that is available to track testing in the U.S., and states should work to address it."
https://coronavirus.jhu.edu/testing/testing-faq/overview#why-are-there-inconsistencies-among-testing-data-for-covid-19

Ideally, each state should be calculating tests vs. cases as this graph from Johns Hopkins shows:
https://coronavirus.jhu.edu/testing/states-comparison

Jump to this post

@colleenyoung, Thank you for sharing this information on calculating the numbers for the covid tests. Apparently without a national standard being used for reporting virus cases, states use different methods in reporting numbers. My personal opinion is that there are probably far more cases and deaths of the virus than are being reported nation wide.

REPLY
@mayofeb2020

@merpreb @tjdog I came from Hong Kong, population about 7 and a half millions. Confirmed death from Covid is 6. They went through SARS, so when covid hits, they knew what is necessary. The compliance rate for face mask is 97%, unfortunately, the other 3% who did not comply are mostly Caucasians. It's hard to believe that some people don't want to take this seriously. That's why we are not seeing a leveling. It's very frustrating. I think some cities are opening up too soon. My county is on the watch list, case number going up and up each day.

Jump to this post

@mayofeb, Your post reminded me of our incredible visits to Hong Kong and China. Those were my first experiences at witnessing thousands of people wearing masks as they went about their day. It seemed so strange at the time but now it is only another reminder of how much we can learn from other countries and cultures...whether with medicine or masks or behavior. It saddens me greatly that what was so long ago feared with China's takeover is coming true now in Hong Kong. Did you grow up in Hong Kong or live there as an adult? Most exotic experiences of my life and such incredible memories! Thank you!

REPLY

@colleenyoung @mayofeb2020 You are right, there are likely serious undercounts.

My sister told me yesterday that a friend of her husband (60 yo) died suddenly of a heart attack on the golf course last week - no previous heart problems. He was tested post-mortem at the request of the medical examiner and found to have Covid. Makes me suspicious - we lost a fairly young friend in May under similar circumstances...unfortunately they were in south Texas where it was thought there were few cases at the time, so no tests done.

Monday on my mega-walk, I stopped in the park to chat with a lady who seemed sad. She lives in a nearby senior coop and no visitors are allowed, so she was waiting for her granddaughter for an outdoor visit. Turns out she brought her husband home from post-surgical rehab in April, he got sick and died within 10 days. Following his death 7 family members and his caregiver tested positive for Covid and 3 ended up hospitalized, one on a vent, but all survived. They later found out there was Covid in the facility at the time he was there, but they were not told and he was never tested...
Sue

REPLY
Please sign in or register to post a reply.