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1.
Topics in Antiviral Medicine ; 30(1 SUPPL):101, 2022.
Article in English | EMBASE | ID: covidwho-1880973

ABSTRACT

Background: The emergence of new SARS-CoV-2 variants raises concerns whether preexisting artificial (vaccine-induced) and natural immunity from prior COVID-19 prevents re-infections. Here, we investigated the differences in primary humoral immune response following SARS-CoV-2 variants of concern (VOCs) infection and aimed to identify the key mutations involved in these differences. Methods: Patients with primary PCR-proven SARS-CoV-2 infection with no history of previous COVID-19 vaccination were included between October 2020 and May 2021 at Amsterdam UMC and via the Dutch SARS-CoV-2 sequence surveillance program. Serum was collected 4-8 weeks after symptom onset and tested for IgG binding and pseudovirus neutralization of the wild-type (WT, Wuhan/D614G), Alpha, Beta and Delta variants. Results: We included 51 COVID-19 patients, who were infected with the WT (n=20), Alpha (n=10), Beta (n=9) or Delta variant (n=12). Generally, the highest neutralization titers were against the autologous virus. After stratifying for hospitalization status, non-hospitalized patients infected with the WT (ID50 817) or Alpha (ID50 2524) variant showed the strongest geometric mean autologous neutralization, followed by the Delta variant (ID50 704) infected participants. By contrast, only one participant infected with the Beta variant showed strong autologous neutralization (median ID50 171). The VOCs also differed in their ability to induce cross-neutralizing responses, with WT-infected patients showing the broadest immune response, followed by Alpha, Delta and Beta infected participants. Additionally, participants infected with the WT, Alpha or Delta variant showed the lowest cross-neutralization against the Beta variant, with a median 5.0-fold (2 to 16-fold), 7.7-fold (2 to 32-fold), and 5.3-fold (1 to 19-fold) reduction compared to the autologous neutralization, respectively. We identified the E484K mutation as the key mutation responsible for this low cross-neutralization. Conclusion: We demonstrated that even small differences in the S protein influences the polyclonal antibody response following infection. The low level of (cross-)neutralization induced by the Beta variant may implicate a higher re-infection risk, but further research of the memory B cell compartment and clinical studies are needed. The broadest cross-neutralizing response observed for WT-infected patients suggests that artificial immunity induced by the current approved COVID-19 vaccines already protects against many re-infections.

2.
Embase; 2022.
Preprint in English | EMBASE | ID: ppcovidwho-335010

ABSTRACT

Variants of concern (VOCs) of SARS-CoV-2 have caused resurging waves of infections worldwide. In the Netherlands, Alpha, Beta, Gamma and Delta variants circulated widely between September 2020 and August 2021. To understand how various control measures had impacted the spread of these VOCs, we analyzed 39,844 SARS-CoV-2 genomes collected under the Dutch national surveillance program. We found that all four VOCs were introduced before targeted flight restrictions were imposed on countries where the VOCs first emerged. Importantly, foreign introductions, predominantly from other European countries, continued during these restrictions. Our findings show that flight restrictions had limited effectiveness in deterring VOC introductions due to the strength of regional land travel importation risks. We also found that the Alpha and Delta variants largely circulated more populous regions with international connections after their respective introduction before asymmetric bidirectional transmissions occurred with the rest of the country and the variant dominated infections in the Netherlands. As countries consider scaling down SARS-CoV-2 surveillance efforts in the post-crisis phase of the pandemic, our results highlight that robust surveillance in regions of early spread is important for providing timely information for variant detection and outbreak control.

3.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-296619

ABSTRACT

ABSTRACT AIM The CoKids study aimed to estimate the community incidence of symptomatic and asymptomatic SARS-CoV-2 in children and parents and to assess the symptomatology of SARS-COV-2 infections relative to SARS-CoV-2 negative respiratory episodes. METHODS In this prospective study, households with at least one child <18 years were recruited from three existing Dutch cohorts. Participation included SARS-CoV-2 screening at 4-6 weeks intervals for all household members during 23 weeks of follow-up and active reporting of new onset respiratory symptoms until July 1 st 2021. Follow-up was temporarily intensified following new onset respiratory symptoms in a household member or a SARS-CoV-2 positive screening test and included daily symptom recording, repeated PCR testing (nose-throat, saliva and fecal samples) and SARS-CoV-2 antibody measurement (paired dried blood spots) in all household members. Age-stratified incidence rates for SARS-CoV-2 positive and negative episodes were calculated. Symptomatology and disease burden of respiratory episodes were compared by SARS-CoV-2 status and age. RESULTS In total 307 households were enrolled including 1209 subjects. We detected 64 SARS-CoV-2 positive and 118 SARS-CoV-2 negative respiratory outbreaks. The highest incidence rate was found in children <12 years for SARS-CoV-2 negative episodes (0.93/ person-year (PY);95%CI: 0.88-0.96). The SARS-CoV-2 incidence in this age-group was 0.21/PY for confirmed only, and 0.41/PY if probable cases were included. SARS-CoV-2 incidence did not differ by age group (p>0.27). Nasal congestion/runny nose, with or without cough and fatigue were the three most prevalent symptom clusters for both SARS-CoV-2 positive and negative respiratory episodes. Among children, no differences were observed in the symptomatology and severity of SARS-CoV-2 positive versus negative respiratory episodes, whereas among adults, SARS-CoV-2 positive episodes had a higher number and severity of symptoms and with a longer duration p<0.001). CONCLUSION Using active, longitudinal household follow up, we detected a high incidence rate of SARS-CoV-2 infections in children that was similar to adults. The findings suggest that after 20 months of COVID-19 pandemic, up to 2/3 of Dutch children < 12 years have been infected with SARS-CoV-2. Symptomatology and disease severity of SARS-CoV-2 in children is similar to respiratory illness from other causes. In adults, SARS-COV-2 positive episodes are characterized by more and prolonged symptoms, and higher severity. These findings may assist decisions on COVID-19 policies targeting children.

4.
Microbiol Spectr ; 9(3): e0088421, 2021 12 22.
Article in English | MEDLINE | ID: covidwho-1532978

ABSTRACT

This study evaluates the performance of the PanBio COVID-19 antigen (Ag) test as part of a hospital infection control policy. Hospital staff was encouraged to get tested for COVID-19 when presenting with SARS-CoV-2-related symptoms. In a period of approximately 5 months, a steady decline in the performance of the Ag test was noted, epidemiologically coinciding with the rise of the SARS-CoV-2 B.1.1.7 (alpha) variant of concern (VOC) in the Netherlands. This led to the hypothesis that the diagnostic performance of the PanBio COVID-19 Ag test was influenced by the infecting viral variant. The results show a significantly lower sensitivity of the PanBio COVID-19 Ag test in persons infected with the B.1.1.7 (alpha) variant of SARS-CoV-2 in comparison with that in persons infected with non-B.1.1.7 variants, also after adjustment for viral load. IMPORTANCE Antigen tests for COVID-19 are widely used for rapid identification of COVID-19 cases, for example, for access to schools, festivals, and travel. There are several FDA- and CE-cleared tests on the market. Their performance has been evaluated mainly on the basis of infections by the classical variant of the causing virus, SARS-CoV-2. This paper provides evidence that the performance of one of the most widely used antigen tests detects significantly fewer cases of COVID-19 by the alpha variant than by the classical variants of SARS-CoV-2. This means that the role of antigen tests needs to be reevaluated in regions where other variants of SARS-CoV-2 predominate.


Subject(s)
Antigens, Viral/immunology , COVID-19 Serological Testing/methods , COVID-19/diagnosis , COVID-19/immunology , SARS-CoV-2/classification , Antibodies, Viral/analysis , Diagnostic Tests, Routine , Humans , Netherlands , SARS-CoV-2/isolation & purification , Sensitivity and Specificity , Viral Load
5.
O'Toole, A.; Hill, V.; Pybus, O. G.; Watts, A.; Bogoch, II, Khan, K.; Messina, J. P.; consortium, Covid- Genomics UK, Network for Genomic Surveillance in South, Africa, Brazil, U. K. Cadde Genomic Network, Tegally, H.; Lessells, R. R.; Giandhari, J.; Pillay, S.; Tumedi, K. A.; Nyepetsi, G.; Kebabonye, M.; Matsheka, M.; Mine, M.; Tokajian, S.; Hassan, H.; Salloum, T.; Merhi, G.; Koweyes, J.; Geoghegan, J. L.; de Ligt, J.; Ren, X.; Storey, M.; Freed, N. E.; Pattabiraman, C.; Prasad, P.; Desai, A. S.; Vasanthapuram, R.; Schulz, T. F.; Steinbruck, L.; Stadler, T.; Swiss Viollier Sequencing, Consortium, Parisi, A.; Bianco, A.; Garcia de Viedma, D.; Buenestado-Serrano, S.; Borges, V.; Isidro, J.; Duarte, S.; Gomes, J. P.; Zuckerman, N. S.; Mandelboim, M.; Mor, O.; Seemann, T.; Arnott, A.; Draper, J.; Gall, M.; Rawlinson, W.; Deveson, I.; Schlebusch, S.; McMahon, J.; Leong, L.; Lim, C. K.; Chironna, M.; Loconsole, D.; Bal, A.; Josset, L.; Holmes, E.; St George, K.; Lasek-Nesselquist, E.; Sikkema, R. S.; Oude Munnink, B.; Koopmans, M.; Brytting, M.; Sudha Rani, V.; Pavani, S.; Smura, T.; Heim, A.; Kurkela, S.; Umair, M.; Salman, M.; Bartolini, B.; Rueca, M.; Drosten, C.; Wolff, T.; Silander, O.; Eggink, D.; Reusken, C.; Vennema, H.; Park, A.; Carrington, C.; Sahadeo, N.; Carr, M.; Gonzalez, G.; Diego, Search Alliance San, National Virus Reference, Laboratory, Seq, Covid Spain, Danish Covid-19 Genome, Consortium, Communicable Diseases Genomic, Network, Dutch National, Sars-CoV-surveillance program, Division of Emerging Infectious, Diseases, de Oliveira, T.; Faria, N.; Rambaut, A.; Kraemer, M. U. G..
Wellcome Open Research ; 6:121, 2021.
Article in English | MEDLINE | ID: covidwho-1450989

ABSTRACT

Late in 2020, two genetically-distinct clusters of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with mutations of biological concern were reported, one in the United Kingdom and one in South Africa. Using a combination of data from routine surveillance, genomic sequencing and international travel we track the international dispersal of lineages B.1.1.7 and B.1.351 (variant 501Y-V2). We account for potential biases in genomic surveillance efforts by including passenger volumes from location of where the lineage was first reported, London and South Africa respectively. Using the software tool grinch (global report investigating novel coronavirus haplotypes), we track the international spread of lineages of concern with automated daily reports, Further, we have built a custom tracking website (cov-lineages.org/global_report.html) which hosts this daily report and will continue to include novel SARS-CoV-2 lineages of concern as they are detected.

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