This study compares the diagnostic performance of a nasopharyngeal swab antigenic test versus the RT-PCR Covid-19 reference test performed with the AllplexTM 2019-nCoV kit (Seegene, South Korea) in symptomatic children presenting at the hospital.
Since March 2020, France, like the rest of the world, has been suffering from the pandemic
caused by SARS CoV-2, which has led to a considerable health crisis. Moreover, the scale of
this epidemic was unexpected for the scientific community and the public authorities, who in
fact had to find diagnostic and management solutions for COVID-19 most often in the short
term. The reference diagnosis of COVID-19 is based on the RT-PCR technique, which allows
diagnosis in the early stages of infectious manifestations.
However, since the French recommendations allow widely and without prescription the access
the screening of individuals in biology laboratories, regardless of age, symptoms and history
of COVID-19 contage, the delays in both the completion of these RT-PCR tests and the return
of their results have increased and have become incompatible with relevant decision-making by
the clinician and control of the epidemic.
Indeed, since the end of August 2020, it takes about ten days to get the result of an
outpatient PCR test. With the increase in the circulation of the SARS-CoV2 virus and the
number of positive cases in several regions of France, the use of rapid testing for SARS
CoV-2 now seems essential.
Another diagnostic method of COVID-19 is the detection of specific SARS CoV-2 antigens in
rhino-pharyngeal secretions and also allows early diagnosis. The qualitative detection of
specific SARS CoV-2 antigens by immunochromatography, from rhino-pharynges samples, has the
advantage of offering a result in about ten minutes. These tests use specific antibodies from
SARS CoV-2 to selectively detect the S protein. Initially these tests like the one developed
by the Belgian firm Coris Bioconcept were developed to identify positive COVID-19 patients.
Thus, they could be used as rapid screening for screening and would be an alternative to
RT-PCR. Their sensitivity varies according to manufacturers and especially according to the
viral load between 60% and 90% with a specificity of more than 99%. The sensitivity of this
test increases in patients with a high viral load, corresponding to a Ct 25.
In this context of active circulation of the virus and with a Positivity rate in RT-PCR of
about 5% in children, it was important for us to evaluate the performance of a rapid
diagnostic test by antigenic detection to optimize their management
Diagnostic Test: Performance of the test antigenic and test RT-PCR
Each patient will have 1 test rapid antigenic Biosynex Covid-19 Ag-BSS with the results in 15-20 minutes and 1 reference test RT-PCR analyzed in microbiology laboratory of the hospital.
Inclusion Criteria:
*Children under 18 years old requiring an RT-PCR Covid-19 defined according to the
algorithm in force at CHI Créteil and which follows the recommendations of the GPIP and the
SFP only for symptomatic children :
- Symptomatic children more then 6 years old: cough, and/or fever, and/or digestive
disorders unless a diagnosis of another infectious disease is made with certainty (ex
Scarlet fever, angina with AMS, enterovirus, urinary tract infections, chickenpox)
- Symptomatic children under 6 years old:
In case of hospitalization or symptoms severe enough to warrant further exploration.
Or who has had a proven contact with a COVID case. Or in contact at home with people
considered at risk for SARS-CoV2 infection. Or whose symptoms do not improve after 3 days.
--Febrile children under 3 months old
- Express agreement of one of the parents present, the presence of only one of the two
parents being recommanded in the current context
- Affiliated with the Social Security plan
Exclusion Criteria:
Refusal of one of the parents or child to participate in the protocol
Centre hospitalier intercommunal de Créteil
Créteil, France
Cabinet de ville
Nogent sur Marne, France
Cabinet Dr Cohen
Saint-Maur-des-Fossés, France
Cabinet de ville 13 Villa Beauséjour
Vincennes, France