Georgia has seen 40,157 cases of COVID-19, according to the 9 a.m. update from the Georgia Department of Public Health's COVID-19 daily status report. The report also indicates that 404,207 COVID-19 tests have been administered as of 9 a.m.; however, 57,000 of those tests are serology tests—or antibody tests, which can be used to determine the prevalence of the disease in a population—rather than diagnostic tests for the virus, said Nancy Nydam, a communications representative for the GDPH, in an email May 21. Nydam responded to a request from Community Impact Newspaper to confirm if serology tests were being included in the number of total tests as reported on the department's COVID-19 status report.
"The Georgia Department of Public Health has received reports of antibody tests since early April and, following current Centers for Disease Control and Prevention methodology, has included tests received in the 'Total Tests' number currently listed on the DPH COVID-19 daily status report. DPH staff is currently working diligently to provide greater transparency in the molecular and serologic testing data displayed in the daily status report," Nydam said in the email. "One of our top priorities is to provide accurate and timely data to the public and we will continue to make every effort to do so."
Nydam also said the department plans on updating the website to separate the two types of tests in the COVID-19 daily status report, as the report currently only states the number of total tests without any separation between serology and diagnostic tests.
"The number of serology tests reported to the DPH is 57,000, and we will continue to get new reports so that number will change daily. Serology tests are useful in determining the prevalence of the disease in the population and have been authorized by the [U.S. Food and Drug Administration] for use in COVID-19," she said in the email. "We will update the website to reflect the number of 'total tests' that are serology vs. [polymerase chain reaction]."
When subtracting the 57,000 serology tests from the reported number of total tests administered, the number of administered COVID-19 tests totals 347,207. With 40,157 positive cases, this means 11.57% of the tests have returned with a positive test result—almost 2% higher than if the percentage was calculated including the 57,000 serology tests.
Nydam said in an email May 21 that patients with only serology results are not considered confirmed COVID-19 cases.
"If a patient has only serology/antibody results, they are not considered confirmed cases but rather a 'probable' case, according to CDC guidance. DPH epidemiologists keep track of these serologic 'positives' as probables but do not include them in our confirmed totals," she said in the email.
Additionally, CDC Public Affairs Representative Kristen Nordlund said in an email May 21 that serology test numbers are also being included with total COVID-19 tests in the CDC's online coronavirus data tracker.
"Initially, when CDC launched its website and its laboratory test reporting, viral testing (tests for current infection) were far more commonly used nationwide than serology testing (tests for past infection). Now that serology is more widely available, CDC is working to differentiate those tests from the viral tests and will report this information, differentiated by test type, publicly on our COVID Data Tracker website in the coming weeks," Nordlund said in the email. "This is just one presentation of this data—often states have their own presentation of the data that is driving their decisions."