Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 10 de 10
Filter
1.
EuropePMC;
Preprint in English | EuropePMC | ID: ppcovidwho-327432

ABSTRACT

Systematic SARS-CoV-2 testing is a valuable tool for infection control and surveillance 1 . However, broad application of high sensitive RT-qPCR testing in children is often hampered due to unpleasant sample collection, limited RT-qPCR capacities, and high costs 2–4 . Here, we developed a high-throughput approach (‘Lolli-Method’) for sensitive SARS-CoV-2 detection in children, combining non-invasive sample collection with an RT-qPCR-pool testing strategy. SARS-CoV-2 infections were diagnosed with sensitivities of 100% and 93.9% when viral loads were >10 6 copies/ml and >10 3 copies/ml in corresponding Naso-/Oropharyngeal-swabs, respectively. For effective application of the Lolli-Method in schools and daycare facilities, SIR-modeling indicated a preferred frequency of two tests per week. The developed test strategy was implemented in 3,700 schools and 698 daycare facilities in Germany, screening over 800,000 individuals twice per week. In a period of 3 months, 6,364 pool-RT-qPCRs tested positive (0.64%) ranging from 0.05% to 2.61% per week. Notably, infections correlated with local SARS-CoV-2 incidences as well as with a school social deprivation index. Moreover, in comparison with the alpha variant, statistical modeling revealed a 31% increase for multiple (≥2 children) infections per class following infections with the delta variant 5 . We conclude that the Lolli-Method is a powerful tool for SARS-CoV-2 surveillance and infection control in schools and daycare facilities.

4.
Vaccine ; 40(1): 43-51, 2022 01 03.
Article in English | MEDLINE | ID: covidwho-1525980

ABSTRACT

OBJECTIVES: With an uprising influence of social media platforms like Twitter and Instagram a multitude of worldwide accessible information is available. Since the beginning of COVID-19 pandemic the exchange of medical information about several topics related to this infectious disease and its vaccination has increased rapidly. The purpose of this investigation was to assess the content associated with COVID-19 vaccination and its side effects and evaluate its educational quality. METHODS: We conducted this retrospective study to investigate 600 Twitter and Instagram posts by #covidvaccinesideeffects due to number of 'likes', comments, type of post, language, its purpose and source. In addition, posts were evaluated due to educational quality by three examiners of different educational levels. RESULTS: The majority of posts showed 0 to 50 "likes" and 0 to 5 comments in English language. A comparison between Twitter and Instagram by the influence of application showed significant differences in number of posts and "likes" or comments (p < 0.05). The major post type were texts for Twitter (251; 83.7%) and videos for Instagram (104; 34.7%). While a majority of posts by #covidvaccinesideeffects report about the occurrence of side effects, the majority of them were mild and general COVID-19 vaccination feedback during the first 4 months was positive. But, only 3 to 7% were rated by "excellent" educational and validatable content. Interrater reliability between all three examiners presented a high concordance with 89% (p = 0.001). CONCLUSIONS: This study presents an analysis of quantity and quality of social media content according to COVID-19 vaccinations and its side effects. It supports the deduction that most of the content on Twitter and Instagram is shared by patients and unclear sources and thus is limited informative. Nevertheless, influence of social media on medical information especially during COVID-19 pandemic is increasing and practitioners have to face its effect on their patients.


Subject(s)
COVID-19 , Social Media , COVID-19 Vaccines , Humans , Pandemics , Reproducibility of Results , Retrospective Studies , SARS-CoV-2 , Vaccination
5.
J Clin Virol ; 145: 105018, 2021 12.
Article in English | MEDLINE | ID: covidwho-1487824

ABSTRACT

OBJECTIVES: The global spread of SARS-CoV-2 is a serious public health issue. Large-scale surveillance screenings are crucial but can exceed test capacities. We (A) optimized test conditions and (B) implemented pool testing of respiratory swabs into SARS-CoV-2 diagnostics. STUDY DESIGN: (A) We determined the optimal pooling strategy and pool size. In addition, we measured the impact of vortexing prior to sample processing, compared a pipette-pooling method (by combining transport medium of several specimens) and a swab-pooling method (by combining several swabs into a test tube filled with PBS) as well as determined the sensitivities of three PCR assays. (B) Finally, we applied high-throughput pool testing for diagnostics. RESULTS: (A) In a low prevalence setting, we defined a preferable pool size of ten in a two-stage hierarchical pool testing strategy. Vortexing of swabs (n = 33) increased cellular yield by a factor of 2.34. By comparing Ct-values of 16 pools generated with two different pooling strategies, pipette-pooling was more efficient compared to swab-pooling. Measuring dilution series of 20 SARS-CoV-2 positive samples in three PCR assays simultaneously revealed detection rates of 85% (assay I), 50% (assay II), and 95% (assay III) at a 1:100 dilution. (B) We systematically pooled 55,690 samples in a period of 44 weeks resulting in a reduction of 47,369 PCR reactions. CONCLUSIONS: For implementing pooling strategies into high-throughput diagnostics, we recommend utilizing a pipette-pooling method, performing sensitivity validation of the PCR assays used, and vortexing swabs prior to analyses. Pool testing for SARS-CoV-2 detection is feasible and effective in a low prevalence setting.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19 Testing , Humans , RNA, Viral , Sensitivity and Specificity , Specimen Handling
6.
EClinicalMedicine ; 39: 101082, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1370502

ABSTRACT

BACKGROUND: The extent to which children and adolescents contribute to SARS-CoV-2 transmission remains not fully understood. Novel high-capacity testing methods may provide real-time epidemiological data in educational settings helping to establish a rational approach to prevent and minimize SARS-CoV-2 transmission. We investigated whether pooling of samples for SARS-CoV-2 detection by RT-qPCR is a sensitive and feasible high-capacity diagnostic strategy for surveillance of SARS-CoV-2 infections in schools. METHODS: In this study, students and school staff of 14 educational facilities in Germany were tested sequentially between November 9 and December 23, 2020, two or three times per week for at least three consecutive weeks. Participants were randomized for evaluation of two different age adjusted swab sampling methods (oropharyngeal swabs or buccal swabs compared to saliva swabs using a 'lolli method'). Swabs were collected and pooled for SARS-CoV-2 RT-qPCR. Individuals of positive pooled tests were retested by RT-qPCR the same or the following day. Positive individuals were quarantined while the SARS-CoV-2 negative individuals remained in class with continued pooled RT-qPCR surveillance. The study is registered with the German Clinical Trials register (registration number: DRKS00023911). FINDINGS: 5,537 individuals were eligible and 3970 participants were enroled and included in the analysis. In students, a total of 21,978 swabs were taken and combined in 2218 pooled RT-qPCR tests. We detected 41 positive pooled tests (1·8%) leading to 36 SARS-CoV-2 cases among students which could be identified by individual re-testing. The cumulative 3-week incidence for primary schools was 564/100,000 (6/1064, additionally 1 infection detected in week 4) and 1249/100,000 (29/2322) for secondary schools. In secondary schools, there was no difference in the number of SARS-CoV-2 positive students identified from pooled oropharyngeal swabs compared to those identified from pooled saliva samples (lolli method) (14 vs. 15 cases; 1·3% vs. 1·3%; OR 1.1; 95%-CI 0·5-2·5). A single secondary school accounted for 17 of 36 cases (47%) indicating a high burden of asymptomatic prevalent SARS-CoV-2 cases in the respective school and community. INTERPRETATION: In educational settings, SARS-CoV-2 screening by RT-qPCR-based pooled testing with easily obtainable saliva samples is a feasible method to detect incident cases and observe transmission dynamics. FUNDING: Federal Ministry of education and research (BMBF; Project B-FAST in "NaFoUniMedCovid19"; registration number: 01KX2021).

7.
BMC Public Health ; 21(1): 1178, 2021 06 21.
Article in English | MEDLINE | ID: covidwho-1277928

ABSTRACT

BACKGROUND: Non-pharmaceutical measures to control the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) should be carefully tuned as they can impose a heavy social and economic burden. To quantify and possibly tune the efficacy of these anti-SARS-CoV-2 measures, we have devised indicators based on the abundant historic and current prevalence data from other respiratory viruses. METHODS: We obtained incidence data of 17 respiratory viruses from hospitalized patients and outpatients collected by 37 clinics and laboratories between 2010-2020 in Germany. With a probabilistic model for Bayes inference we quantified prevalence changes of the different viruses between months in the pre-pandemic period 2010-2019 and the corresponding months in 2020, the year of the pandemic with noninvasive measures of various degrees of stringency. RESULTS: We discovered remarkable reductions δ in rhinovirus (RV) prevalence by about 25% (95% highest density interval (HDI) [-0.35,-0.15]) in the months after the measures against SARS-CoV-2 were introduced in Germany. In the months after the measures began to ease, RV prevalence increased to low pre-pandemic levels, e.g. in August 2020 δ=-0.14 (95% HDI [-0.28,0.12]). CONCLUSIONS: RV prevalence is negatively correlated with the stringency of anti-SARS-CoV-2 measures with only a short time delay. This result suggests that RV prevalence could possibly be an indicator for the efficiency for these measures. As RV is ubiquitous at higher prevalence than SARS-CoV-2 or other emerging respiratory viruses, it could reflect the efficacy of noninvasive measures better than such emerging viruses themselves with their unevenly spreading clusters.


Subject(s)
COVID-19 , Rhinovirus , Bayes Theorem , Germany , Humans , Prevalence , SARS-CoV-2
8.
Eur J Clin Microbiol Infect Dis ; 40(5): 1063-1071, 2021 May.
Article in English | MEDLINE | ID: covidwho-1061091

ABSTRACT

Evaluation and power of seroprevalence studies depend on the performed serological assays. The aim of this study was to assess four commercial serological tests from EUROIMMUN, DiaSorin, Abbott, and Roche as well as an in-house immunofluorescence and neutralization test for their capability to identify SARS-CoV-2 seropositive individuals in a high-prevalence setting. Therefore, 42 social and working contacts of a German super-spreader were tested. Consistent with a high-prevalence setting, 26 of 42 were SARS-CoV-2 seropositive by neutralization test (NT), and immunofluorescence test (IFT) confirmed 23 of these 26 positive test results (NT 61.9% and IFT 54.8% seroprevalence). Four commercial assays detected anti-SARS-CoV-2 antibodies in 33.3-40.5% individuals. Besides an overall discrepancy between the NT and the commercial assays regarding their sensitivity, this study revealed that commercial SARS-CoV-2 spike-based assays are better to predict the neutralization titer than nucleoprotein-based assays are.


Subject(s)
COVID-19 Serological Testing/methods , COVID-19/diagnosis , COVID-19/epidemiology , SARS-CoV-2/isolation & purification , Adolescent , Adult , Aged , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/blood , COVID-19 Serological Testing/standards , Contact Tracing , Female , Humans , Immunoassay , Male , Middle Aged , Neutralization Tests , Prevalence , SARS-CoV-2/immunology , Sensitivity and Specificity , Young Adult
10.
Viruses ; 12(9)2020 09 18.
Article in English | MEDLINE | ID: covidwho-789516

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents a global health emergency. To improve the understanding of the systemic component of SARS-CoV-2, we investigated if viral load dynamics in plasma and respiratory samples are associated with antibody response and severity of coronavirus disease 2019 (COVID-19). SARS-CoV-2 RNA was found in plasma samples from 14 (44%) out of 32 patients. RNAemia was detected in 5 out of 6 fatal cases. Peak IgG values were significantly lower in mild/moderate than in severe (0.6 (interquartile range, IQR, 0.4-3.2) vs. 11.8 (IQR, 9.9-13.0), adjusted p = 0.003) or critical cases (11.29 (IQR, 8.3-12.0), adjusted p = 0.042). IgG titers were significantly associated with virus Ct (Cycle threshold) value in plasma and respiratory specimens ((ß = 0.4, 95% CI (confidence interval, 0.2; 0.5), p < 0.001 and ß = 0.5, 95% CI (0.2; 0.6), p = 0.002). A classification as severe or a critical case was additionally inversely associated with Ct values in plasma in comparison to mild/moderate cases (ß = -3.3, 95% CI (-5.8; 0.8), p = 0.024 and ß = -4.4, 95% CI (-7.2; 1.6), p = 0.007, respectively). Based on the present data, our hypothesis is that the early stage of SARS-CoV-2 infection is characterized by a primary RNAemia, as a potential manifestation of a systemic infection. Additionally, the viral load in plasma seems to be associated with a worse disease outcome.


Subject(s)
Antibodies, Viral/blood , Betacoronavirus/isolation & purification , Coronavirus Infections/virology , Pneumonia, Viral/virology , RNA, Viral/blood , Aged , Betacoronavirus/genetics , Betacoronavirus/immunology , COVID-19 , Coronavirus Infections/blood , Coronavirus Infections/pathology , Female , Germany/epidemiology , Hospitalization , Humans , Immunoglobulin G/blood , Male , Middle Aged , Pandemics , Pneumonia, Viral/blood , Pneumonia, Viral/pathology , RNA, Viral/analysis , Respiratory System/virology , SARS-CoV-2 , Severity of Illness Index , Viral Load , Viremia/blood , Viremia/pathology , Viremia/virology
SELECTION OF CITATIONS
SEARCH DETAIL