9 mei 2021: Bron: JAMA 22 april 2021

Uit een studie bij 3448 mensen in een min of meer besloten "bubbel" van professionele basketballers en personeel blijkt dat mensen die eerder besmet zijn geweest met het coronavirus - Covid-19  en daarvan zijn genezen geen gevaar zijn om anderen te besmetten. Zelfs niet in een omgeving waar geen maatregelen werden getroffen van afstand houden, mondmaskers dragen enz. 

De National Basketball Association (NBA) volgde tijdens een gesloten campusprogramma in 2020 met dagelijkse SARS-CoV-2-testen voor totaal 3448 personen. Van de 3648 deelnemers aan het programma hadden 36 mensen herhaaldelijk positieve PCR-tests voor SARS-CoV-2. Hiervan ondervonden 33 mensen een infectie voordat ze de campus betraden en 3 bleken besmet te zijn tijdens de vereiste quarantaineperiode na het betreden van de campus.

Ondanks deze positieve tests mochten de deelnemers deelnemen aan maskervrije activiteiten (bijv. Oefenen, spelletjes) als de symptomen waren verdwenen en er 10 dagen waren verstreken sinds de eerste infectie. De tests bleven gemiddeld 30 dagen positief (spreiding 14-68 dagen) en de drempelwaarden voor de cyclus waren doorgaans erg hoog (gemiddeld 34,1), wat wijst op enkele kopieën van viraal nucleïnezuur. Gedurende 1480 mandagen van directe blootstelling vonden geen tweede besmettingen plaats.

In een retrospectieve cohortstudie beoordeelden onderzoekers het risico op secundaire transmissie onder die spelers en personeel met herhaaldelijk positieve tests na het einde van de isolatie. Klik op de titel voor het studieversalg van deze studie die in JAMA swerd gepubliceerd:

editorial comment icon 
Editorial comment
Key Points

Question  Do individuals who have clinically recovered from COVID-19 but continue to test positive still transmit SARS-CoV-2?

Findings  In this cohort study of 3648 participants, data were collected during the resumption of the 2020 National Basketball Association season in a closed environment. Individuals who recovered clinically from COVID-19 but continued to test positive did not transmit SARS-CoV-2 to others, despite close proximity with susceptible individuals.

Meaning  US Centers of Disease Control and Prevention guidelines to allow discontinuation of isolation precautions for asymptomatic individuals after 10 days from symptom onset or first reverse-transcription–polymerase chain reaction (RT-PCR) positive test result, without requiring a negative RT-PCR test result, was sufficient to prevent transmission of SARS-CoV-2 in this 2020 cohort.


Importance  Clinical data are lacking regarding the risk of viral transmission from individuals who have positive reverse-transcription–polymerase chain reaction (RT-PCR) SARS-CoV-2 test results after recovery from COVID-19.

Objective  To describe case characteristics, including viral dynamics and transmission of infection, for individuals who have clinically recovered from SARS-CoV-2 infection but continued to have positive test results following discontinuation of isolation precautions.

Design, Setting, and Participants  This retrospective cohort study used data collected from June 11, 2020, to October 19, 2020, as part of the National Basketball Association (NBA) closed campus occupational health program in Orlando, Florida, which required daily RT-PCR testing and ad hoc serological testing for SARS-CoV-2 IgG antibodies. Nearly 4000 NBA players, staff, and vendors participated in the NBA’s regular and postseason occupational health program in Orlando. Persistent positive cases were those who recovered from a documented SARS-CoV-2 infection, satisfied US Centers for Disease Control and Prevention criteria for discontinuation of isolation precautions, and had at least 1 postinfection positive RT-PCR test(s) result.

Exposures  Person-days of participation in indoor, unmasked activities that involved direct exposure between persistent positive cases and noninfected individuals.

Main Outcomes and Measures  Transmission of SARS-CoV-2 following interaction with persistent positive individuals, as measured by the number of new COVID-19 cases in the Orlando campus program.

Results  Among 3648 individuals who participated, 36 (1%) were persistent positive cases, most of whom were younger than 30 years (24 [67%]) and male (34 [94%]). Antibodies were detected in 33 individuals (91.7%); all remained asymptomatic following the index persistent positive RT-PCR result. Cycle threshold values for persistent positive RT-PCR test results were typically above the Roche cobas SARS-CoV-2 limit of detection. Cases were monitored for up to 100 days (mean , 51 [23.9] days), during which there were at least 1480 person-days of direct exposure activities, with no transmission events or secondary infections of SARS-CoV-2 detected (0 new cases).

Conclusions and Relevance  In this retrospective cohort study of the 2020 NBA closed campus occupational health program, recovered individuals who continued to test positive for SARS-CoV-2 following discontinuation of isolation were not infectious to others. These findings support time-based US Centers of Disease Control and Prevention recommendations for ending isolation.


Vibholm  LK, Nielsen  SSF, Pahus  MH,  et al.  SARS-CoV-2 persistence is associated with antigen-specific CD8 T-cell responses.   EBioMedicine. 2021;64:103230. doi:10.1016/j.ebiom.2021.103230PubMedGoogle Scholar
Wu  J, Liu  X, Liu  J,  et al.  Coronavirus disease 2019 test results after clinical recovery and hospital discharge among patients in China.   JAMA Netw Open. 2020;3(5):e209759. doi:10.1001/jamanetworkopen.2020.9759
ArticlePubMedGoogle Scholar
Wu  Y, Guo  C, Tang  L,  et al.  Prolonged presence of SARS-CoV-2 viral RNA in faecal samples.   Lancet Gastroenterol Hepatol. 2020;5(5):434-435. doi:10.1016/S2468-1253(20)30083-2PubMedGoogle ScholarCrossref
Hartman  WR, Hess  AS, Connor  JP.  Persistent viral RNA shedding after COVID-19 symptom resolution in older convalescent plasma donors.   Transfusion. 2020;60(10):2189-2191. doi:10.1111/trf.15927PubMedGoogle ScholarCrossref
Zhang  B, Liu  S, Dong  Y,  et al.  Positive rectal swabs in young patients recovered from coronavirus disease 2019 (COVID-19).   J Infect. 2020;81(2):e49-e52. doi:10.1016/j.jinf.2020.04.023PubMedGoogle ScholarCrossref
Xu  K, Chen  Y, Yuan  J,  et al.  Factors associated With prolonged viral RNA shedding in patients with coronavirus disease 2019 (COVID-19).   Clin Infect Dis. 2020;71(15):799-806. doi:10.1093/cid/ciaa351PubMedGoogle ScholarCrossref
Liu  WD, Chang  SY, Wang  JT,  et al.  Prolonged virus shedding even after seroconversion in a patient with COVID-19.   J Infect. 2020;81(2):318-356.PubMedGoogle Scholar
Molina  LP, Chow  SK, Nickel  A, Love  JE.  Prolonged detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in an obstetric patient with antibody seroconversion.   Obstet Gynecol. 2020;136(4):838-841. doi:10.1097/AOG.0000000000004086PubMedGoogle ScholarCrossref
Hong  K, Cao  W, Liu  Z,  et al.  Prolonged presence of viral nucleic acid in clinically recovered COVID-19 patients was not associated with effective infectiousness.   Emerg Microbes Infect. 2020;9(1):2315-2321. doi:10.1080/22221751.2020.1827983PubMedGoogle ScholarCrossref
Qi  L, Yang  Y, Jiang  D,  et al.  Factors associated with the duration of viral shedding in adults with COVID-19 outside of Wuhan, China: a retrospective cohort study.   Int J Infect Dis. 2020;96:531-537. doi:10.1016/j.ijid.2020.05.045PubMedGoogle ScholarCrossref
Rhee  C, Kanjilal  S, Baker  M, Klompas  M.  Duration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infectivity: when is it safe to discontinue isolation?   Clin Infect Dis. 2020;ciaa1249. doi:10.1093/cid/ciaa1249PubMedGoogle Scholar
Avanzato  VA, Matson  MJ, Seifert  SN,  et al.  Case study: prolonged infectious SARS-CoV-2 shedding from an asymptomatic immunocompromised individual with cancer.   Cell. 2020;183(7):1901-1912.e9, e1909. doi:10.1016/j.cell.2020.10.049PubMedGoogle ScholarCrossref
Korea Centers for Disease Control and Prevention. Findings from investigation and analysis of re-positive cases. Accessed December 18, 2020. https://www.cdc.go.kr/board/board.es?mid=a30402000000&bid=0030&act=view&list_no=367267&nPage=1external%20icon
Centers for Disease Control and Prevention. Discontinuation of isolation for persons with COVID-19 not in healthcare settings. Accessed December 18, 2020. https://www.cdc.gov/coronavirus/2019-ncov/hcp/disposition-in-home-patients.html
Centers for Disease Control and Prevention. Duration of isolation and precautions for adults with COVID-19. Accessed December 18, 2020. https://www.cdc.gov/coronavirus/2019-ncov/hcp/duration-isolation.html#
Dores  H, Cardim  N.  Return to play after COVID-19: a sport cardiologist’s view.   Br J Sports Med. 2020;54(19):1132-1133. doi:10.1136/bjsports-2020-102482PubMedGoogle ScholarCrossref
DiFiori  JP, Green  G, Meeuwisse  W, Putukian  M, Solomon  GS, Sills  A.  Return to sport for North American professional sport leagues in the context of COVID-19.   Br J Sports Med. 2021;55(8):417-421. doi:10.1136/bjsports-2020-103227PubMedGoogle ScholarCrossref
Kissler  SM, Fauver  JR, Mack  C,  et al  SARS-CoV-2 viral dynamics in acute infections.   medRxiv. 2020:2020.2010.2021.20217042.Google Scholar
Cobas®. Qualitative assay for use on the cobas® 6800/8800 Systems. Accessed December 18, 2020. https://www.fda.gov/media/136049/download
Panther Fusion® SARS-CoV-2. SARS-CoV-2 assay (Panther Fusion® System). Accessed December 18, 2020. https://www.fda.gov/media/136156/download
US Food and Drug Administration. Coronavirus (COVID-19) update: FDA authorizes first tests that estimate a patient’s antibodies from past SARS-CoV-2 infection. Accessed December 18, 2020. https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-first-tests-estimate-patients-antibodies-past-sars-cov-2
Abbott. SARS-CoV-2 IgG. Accessed December 18, 2020. https://www.fda.gov/media/137383/download
Vitros. VITROS immunodiagnostic products anti-SARS-CoV-2 IgG reagent pack. Accessed December 18, 2020. https://www.fda.gov/media/137363/download
US Food and Drug Administration. Elecsys anti-SARS-CoV-2—FDA. Accessed March 11, 2021. https://www.fda.gov/media/137602/download
US Centers for Disease Control and Prevention. Using antibody tests for COVID-19. Accessed December 18, 2020. https://www.cdc.gov/coronavirus/2019-ncov/lab/resources/antibody-tests.html#:~:text=In%20general%2C%20a%20positive%20antibody,to%203%20weeks%20after%20infection
Kim  JH, Levine  BD, Phelan  D,  et al.  Coronavirus disease 2019 and the athletic heart: emerging perspectives on pathology, risks, and return to play.   JAMA Cardiol. 2021;6(2):219-227. doi:10.1001/jamacardio.2020.5890
ArticlePubMedGoogle ScholarCrossref
Mack  CD, Wasserman  EB, Perrine  CG,  et al; NFL COVID-19 Advisory and Operational Team.  Implementation and evolution of mitigation measures, testing, and contact tracing in the National Football League, August 9-November 21, 2020.   MMWR Morb Mortal Wkly Rep. 2021;70(4):130-135. doi:10.15585/mmwr.mm7004e2PubMedGoogle ScholarCrossref
Liotti  FM, Menchinelli  G, Marchetti  S,  et al.  Assessment of SARS-CoV-2 RNA test results among patients who recovered from COVID-19 with prior negative results.   JAMA Intern Med. 2020. Published online November 12, 2020. doi:10.1001/jamainternmed.2020.7570
ArticlePubMedGoogle Scholar
Tillett  RL, Sevinsky  JR, Hartley  PD,  et al.  Genomic evidence for reinfection with SARS-CoV-2: a case study.   Lancet Infect Dis. 2021;21(1):52-58. doi:10.1016/S1473-3099(20)30764-7PubMedGoogle ScholarCrossref
Gupta  V, Bhoyar  RC, Jain  A,  et al.  Asymptomatic reinfection in two healthcare workers from India with genetically distinct SARS-CoV-2.   Clin Infect Dis. 2020;ciaa1451. doi:10.1093/cid/ciaa1451PubMedGoogle Scholar
To  KK, Hung  IF, Ip  JD,  et al.  COVID-19 re-infection by a phylogenetically distinct SARS-coronavirus-2 strain confirmed by whole genome sequencing.   Clin Infect Dis. 2020;ciaa1275. doi:10.1093/cid/ciaa1275PubMedGoogle Scholar
US Centers for Disease Control and Prevention. Test for past infection. Accessed December 18, 2020. https://www.cdc.gov/coronavirus/2019-ncov/testing/serology-overview.html
Qiao  X-M, Xu  X-F, Zi  H,  et al.  Re-positive cases of nucleic acid tests in discharged patients with COVID-19: a follow-up study.   Front Med (Lausanne). 2020;7(349):349. doi:10.3389/fmed.2020.00349PubMedGoogle ScholarCrossref
Agarwal  V, Venkatakrishnan  AJ, Puranik  A,  et al.  Long-term SARS-CoV-2 RNA shedding and its temporal association to IgG seropositivity.   Cell Death Discov. 2020;6(1):138. doi:10.1038/s41420-020-00375-yPubMedGoogle ScholarCrossref
Ridgway  JP, Shah  NS, Robicsek  AA.  Prolonged shedding of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) RNA among patients with coronavirus disease 2019 (COVID-19).   Infect Control Hosp Epidemiol. 2020;41(10):1235-1236. doi:10.1017/ice.2020.307PubMedGoogle ScholarCrossref
Kissler  S, Fauver  JR, Mack  CD,  et al. Densely sampled viral trajectories suggest longer duration of acute infection with B.1.1.7 variant relative to non-B.1.1.7 SARS-CoV-2 Accessed March 11, 2021. https://nrs.harvard.edu/URN-3:HUL.INSTREPOS:37366884


Plaats een reactie ...

Reageer op "Herstelde personen na eerder besmet te zijn geweest met coronavirus - SARS-CoV-2 waren niet besmettelijk voor anderen blijkt uit retrospectieve studie bij 3448 professionele basketballers en personeel."

Gerelateerde artikelen

Gerelateerde artikelen

Herstelde personen na eerder >> Ivermectine, een zogeheten >> Neusspray van SaNOtize blijkt >> Monoklonaal antilichaam VIR- >> Regelmatig bewegen en sporten >> Het coronavirus - Covid-19 >> 34 procent van de mensen die >> Vaccins van Pfizer-Biontech >> Vaccineren tegen het coronavirus >> Kinderen in basisschoolleeftijd >>