Phamatech COVID-19 IgG/IgM Rapid Test
FREQUENTLY ASKED QUESTIONS:
- Negative results do not rule out SARS-CoV-2 infection, particularly in those who have been in contact with the virus. Follow-up testing with a molecular diagnostic (nasal or throat swab) should be considered to rule out infection in these individuals.
- Results from antibody testing should not be used as the sole basis to diagnose or exclude SARS-CoV-2 infection or to inform infection status.
- Positive results may be due to past or present infection with non-SARS-CoV-2 coronavirus strains, such as coronavirus HKU1, NL63, OC43, or 229E, cross reacting with antibodies for other viruses not tested for.
- This test is not for the screening of donated blood
- This test is for professional use.
- Confirmed COVID-19 infection and a negative antibody test: the nasal or throat swab test (diagnostic test), which directly detects the virus - was positive, while antibody test (serologic test) several weeks later is negative. Q: How does this make any sense? A: Either the test was wrong (either the test was done too early, or inherited quality of the test – what is called False Negative/or Relative Sensitivity) or the patient failed to develop protective immunity. The clinical performance of Phamatech COVID-19 IgG/IgM Rapid Test was evaluated in patients with confirmed COVID-19 infection. The study yielded 96.9% Relative Sensitivity
- Suspected COVID-19 infection and a positive antibody test: a patient had a mild cold-like symptoms (or no symptoms) a while ago and his antibody test returns positive. It should be noted that Phamatech COVID-19 IgG/IgM Rapid Test was also evaluated in patients with confirmed COVID-19 infection for Relative Specificity yielding 96.3%, which means that 96.3% are true positive for COVID-19 infection. The remaining 3.7% who would have positive serology – antibodies, are incorrectly identified as test positive (false positives) due to cross-reactivity with non-SARS-CoV-2 coronavirus strains.
- It should be clear, that while preliminary data is promising, recovery from the infection does not guarantee immunity. Furthermore, if true immunity develops, it is unclear how long it will last.
Common Scenarios in Interpretation of Serologic Testing:
All test results are presumptive and should be confirmed by clinical observation and/or by approved diagnostic testing.
Key Scientific Considerations:
- At this time, there is a preliminary evidence that antibodies to SARS-CoV-2, the coronavirus that causes COVID-19 disease, will prevent reinfection. Several small-size group studies have shown that antibodies from donors who had recovered from COVID-19 infection were able to neutralize, or prevent reinfection, with SARS-CoV-2. Nonetheless, we do not yet know if all COVID-19 patients are able to mount effective immunity and prevent reinfection.
- There are reports of COVID-19 patients who recovered completely, and then developed new symptoms and tested positive for the virus a second time. It is not clear if this results from a reinfection (new infection) or if they had an unexplained reactivation, and relapse of previously infected state. It’s also possible that some of the tests have had false positive results, meaning that the test was positive, but the patient did not have COVID-19 infection.
- Another important question with COVID-19 immunity is how long it will last and whether the presence of antibodies prevents reinfection. While some other virus strains causing common cold show declining immunity weeks after infection, SARS-CoV, the causative agent of the 2003 SARS pandemic, is genetically more similar to SARS-CoV-2 and shows a more reassuring immunity data. The longer immunity duration can provide enough time to protect individuals until development and distribution of a vaccine.
- Immune testing for COVID-19 is valuable. It can help to understand the extent of the virus’s transmission in the population and true occurrence of SARS-CoV-2 infection across a population (prevalence). In addition, this data can help to answer questions about the true severity of the disease and its mortality rate.
- It can also help to identify individuals who are still vulnerable to the infection. How prevalent disease transmission is from people without symptoms may change and ease shelter-in-place restrictions.
- We are using a qualitative test that gives a YES/NO result for the presence of antibodies.
- The test is not faultless. It is 96.9% “sensitive,” meaning almost 97% of people who were infected with COVID-19 and have antibodies will test positive while remaining 3% will not. It has 96.3% “specificity,” which means that about 96% of tested individuals with positive antibodies have truly serologic evidence for the past COVID-19 infection.
- The reality is that many questions about COVID-19 right now don't have an answer.
For questions and answers please email: covid@butcharthealthcenter