Virological or serological test: how to know which Covid-19 screening you need
For several weeks, the government has been recommending that the French get tested as soon as the first symptoms of Covid-19 appear. The infection can start with cough, fever, shortness of breath, diarrhea, muscle aches, rashes, or loss of taste and smell. It is also recommended to carry out a screening test after contact with a sick person. PCR, serological, rapid tests … There are different ways to screen for Covid-19.
Covid-19: what are the different screening tests?
- Les tests PCR : RT-PCR or virological tests are nasopharyngeal swabs. The healthcare professional takes cells from the back of the patient’s nose with a swab. Part of the genetic material removed is then amplified by a polymerase chain reaction (PCR) technique.
Virological tests can detect people infected with the virus, but they do not spot the virus until symptoms appear or after they disappear. If a patient develops characteristics similar to those of Covid-19, they can go to a laboratory or screening center to perform a PCR test. Usually, results are delivered after 24 hours, but this can take longer. When the result is positive, the patient is placed in a fortnight.
Since July 25, PCR tests are now accessible to everyone without a prescription and reimbursed by Health Insurance. The wait is sometimes long for the results of this screening. The government has therefore extended the list of health professionals authorized to perform these tests. In addition to biologists and laboratory technicians, nurses, orderlies, firefighters, rescuers, odontology, maieutics and pharmacy students can perform PCR tests.
- Serological tests: A serological test is characterized by a blood sample. The serum collected is then analyzed in order to look for any antibodies. These are made by the body to fight against coronavirus infection. Thanks to this blood test, the medical profession can identify people who have been contaminated with Sars-CoV-2. Results are available over the next 24 hours.
The longevity of these antibodies is not yet known. In a recent study, researchers from King’s College London (UK) investigated whether these antibodies protect patients from a second Covid-19 infection. Their results were published in the journal MedRxiv. According to them, the patients developed a strong immunity, but after a few months it diminished or even disappeared.
It is possible to perform a serological test without a prescription, but it will not be reimbursed by Health Insurance. “In view of the current state of scientific knowledge on the immunity associated with exposure to the virus, it is not advisable to carry out this examination without medical support (…) In the event of the realization of a test, it is advisable to consult a doctor in order to avoid any misinterpretation of the results as well as to benefit from advice specific to the person’s clinical situation depending on the test result “, explains the Ministry of Health on its online platform.
Rapid tests
These are also serological tests. The patient is taken a drop of blood to detect the presence of antibodies in his body. These rapid tests are available in pharmacies and the results are obtained in a few minutes. Without a prescription, they are not reimbursed by social security.
Source :
