Fatores do absenteísmo em primeira consulta num ambulatório de oncologia em um Hospital Universitário / xxx

RESUMO Introdução: o absenteísmo dos usuários de sistemas de saúde representa um grande problema para as organizações. O objetivo deste estudo foi identificar as razões para o absenteísmo dos pacientes em consulta médicas. Metodologia: pesquisa de campo nos ambulatórios de oncologia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto. Os pacientes que não compareceram à primeira consulta em 2013 (356) foram contatados por meio telefônico, dos quais 299 não foi possível o contato por apresentarem telefone inválido, desligado, fora da área de cobertura ou por não atenderem a ligação. Resultados: 57 pacientes foram entrevistados e apontaram os motivos para falta. As respostas foram categorizadas. Os resultados mostraram que 27 pacientes (47%) não compareceram à consulta por motivos relacionados ao indivíduo ou comportamento, sendo "consultei-me em outro lugar" o mais recorrente (12,30%), seguido de "consulta coincidiu com outro compromisso" (7,02%) e "não me lembro o motivo" (7,02%). Individualmente, o motivo mais citado pelos pacientes foi "eu não faltei a consulta" (31,6%), o que sugere problemas de comunicação. Conclusão: as principais razões para o absenteísmo estão relacionadas ao indivíduo e que problemas de cadastro do paciente e comunicação dificultam a compreensão das causas do absenteísmo. (AU)

ABSTRACT Introduction: absenteeism of health system users is a major problem for organizations. The study aimed to identify the factors of absenteeism in outpatients at the General Hospital of the Medical School of Ribeirão Preto oncology clinics. Methodology: patients who did not attend the first appointment in 2013 (356) were contacted by telephone, of which 299 were not able to contact because they presented an invalid telephone number, disconnected, outside the coverage area or because they did not answer the call. Results: 57 patients were interviewed and indicated reasons for no show. The answers were categorized. The results showed that 27 patients (47%) did not attend the appointment for reasons related to the individual or behavior, the cause "I had an appointment elsewhere" was the most recurrent (12.30%), followed by "the appointment happened at the same time of another commitment" (7.02%) and "I cannot remember the reason" (7.02%). Individually, the most cited reason by the patients was "I did not miss the appointment" 18 (31.6%), thus suggesting communication problems. Conclusion:the main reasons for absenteeism are related to the individual and problems of patient registration and communication make it difficult to understand the causes of absenteeism. (AU)

Análise comparativa do risco cardiovascular com características clínicas não inclusas no escore de Framingham / Comparative analysis of cardiovascular risk with clinical features not included in the Framingham risk score

OBJETIVO: Avaliar o risco de doença cardiovascular em 10 anos, por meio do escore de Framingham, em pacientes internados nas enfermarias de clínica médica de um hospital geral, e a prevalência de variáveis clínicas não contempladas por este escore nessa mesma população, além de correlacionar a prevalência dessas variáveis com o risco cardiovascular calculado. MÉTODOS: De dezembro de 2014 a maio de 2015, foram examinados os pacientes sem história ou evidência de doença cardiovascular. Foram coletados os dados para cálculo do risco. Foram ainda avaliadas as seguintes variáveis não inclusas no escore de Framingham: histórico familiar de doença cardiovascular, sedentarismo, circunferência abdominal, etnia e pressão arterial diastólica. Dividimos os pacientes em dois grupos: um com risco cardiovascular elevado e outro com risco não elevado. RESULTADOS: O risco cardiovascular em 10 anos na casuística (n=100) foi de 17,89%. A prevalência das variáveis não inclusas no escore foram antecedente familiar (48%); sedentarismo (81%); obesidade central (70%); brancos vs. não brancos (56% vs. 44%); pressão arterial diastólica média (79,53mmHg). O único dado não incluso no escore que apresentou associação estatisticamente significativa com o risco cardiovascular elevado foi a pressão arterial diastólica (χ²=5,8275; p=0,0158). CONCLUSÃO: O achado da pressão arterial diastólica sugere valor preditivo cardiovascular para este fator. As demais variáveis ausentes no escore não se associaram com o risco cardiovascular elevado.

OBJECTIVES: To assess the risk of cardiovascular disease in tem years, through Framingham score, in patients admitted to the medical wards of a general hospital, and the prevalence of clinical variables not contemplated by this score in that population, in addition to correlate the prevalence of these variables with calculated cardiovascular risk. METHODS: From December 2014 to May 2015, patients with no history or evidence of cardiovascular disease were examined. Data for risk calculation were collected. In addition, the following variables that were not included in Framingham risk score were evaluated: family history of cardiovascular disease, physical inactivity, abdominal circumference, ethnicity and diastolic blood pressure. Patients were divided into two groups: one with high cardiovascular risk, and another with low risk. RESULTS: Cardiovascular risk in ten years in the series (n=100) was 17.89%. The prevalence of the variables not included in the score were: family history, 48%; sedentary lifestyle, 81%; central obesity, 70%; white vs. non-white, 56% vs 44%; mean diastolic blood pressure, 79.53mmHg. The only data showing statistically significant association with increased cardiovascular risk that were not included in the score was diastolic blood pressure (χ²=5.8275; p=0.0158). CONCLUSION: The finding of diastolic blood pressure suggests cardiovascular predictive value for this factor. The other variables that were not present in the score were not associated with increased cardiovascular risk.

Genome Detective Coronavirus Typing Tool for rapid identification and characterization of novel coronavirus genomes

SummaryGenome Detective is a web-based, user-friendly software application to quickly and accurately assemble all known virus genomes from next generation sequencing datasets. This application allows the identification of phylogenetic clusters and genotypes from assembled genomes in FASTA format. Since its release in 2019, we have produced a number of typing tools for emergent viruses that have caused large outbreaks, such as Zika and Yellow Fever Virus in Brazil. Here, we present The Genome Detective Coronavirus Typing Tool that can accurately identify novel coronavirus (2019-nCoV) sequences isolated in China and around the world. The tool can accept up to 2,000 sequences per submission and the analysis of a new whole genome sequence will take approximately one minute. The tool has been tested and validated with hundreds of whole genomes from ten coronavirus species, and correctly classified all of the SARS-related coronavirus (SARSr-CoV) and all of the available public data for 2019-nCoV. The tool also allows tracking of new viral mutations as the outbreak expands globally, which may help to accelerate the development of novel diagnostics, drugs and vaccines. AvailabilityAvailable online: https://www.genomedetective.com/app/typingtool/cov * Contactkoen@emweb.be and deoliveira@ukzn.ac.za Supplementary informationSupplementary data is available online.

Whole Genome Sequencing of SARS-CoV-2: Adapting Illumina Protocols for Quick and Accurate Outbreak Investigation During a Pandemic

The COVID-19 pandemic spread very fast around the world. A few days after the first detected case in South Africa, an infection started a large hospital outbreak in Durban, KwaZulu-Natal. Phylogenetic analysis of SARS-CoV-2 genomes can be used to trace the path of transmission within a hospital. It can also identify the source of the outbreak and provide lessons to improve infection prevention and control strategies. In this manuscript, we outline the obstacles we encountered in order to genotype SARS-CoV-2 in real-time during an urgent outbreak investigation. In this process, we encountered problems with the length of the original genotyping protocol, reagent stockout and sample degradation and storage. However, we managed to set up three different library preparation methods for sequencing in Illumina. We also managed to decrease the hands on library preparation time from twelve to three hours, which allowed us to complete the outbreak investigation in just a few weeks. We also fine-tuned a simple bioinformatics workflow for the assembly of high-quality genomes in real-time. In order to allow other laboratories to learn from our experience, we released all of the library preparation and bioinformatics protocols publicly and distributed them to other laboratories of the South African Network for Genomics Surveillance (SANGS) consortium.

SARS-CoV-2 evolves increased infection elicited cell death and fusion in an immunosuppressed individual

The milder clinical manifestations of Omicron infection relative to pre-Omicron SARS-CoV-2 raises the possibility that extensive evolution results in reduced pathogenicity. To test this hypothesis, we quantified induction of cell fusion and cell death in SARS-CoV-2 evolved from ancestral virus during long-term infection. Both cell fusion and death were reduced in Omicron BA.1 infection relative to ancestral virus. Evolved virus was isolated at different times during a 6-month infection in an immunosuppressed individual with advanced HIV disease. The virus isolated 16 days post-reported symptom onset induced fusogenicity and cell death at levels similar to BA.1. However, fusogenicity was increased in virus isolated at 6 months post-symptoms to levels intermediate between BA.1 and ancestral SARS-CoV-2. Similarly, infected cell death showed a graded increase from earlier to later isolates. These results may indicate that, at least by the cellular measures used here, evolution in long-term infection does not necessarily attenuate the virus.

High Resolution analysis of Transmission Dynamics of Sars-Cov-2 in Two Major Hospital Outbreaks in South Africa Leveraging Intrahost Diversity

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes acute, highly transmissible respiratory infection in both humans and wide range of animal species. Its rapid spread globally and devasting effects have resulted into a major public health emergency prompting the need for methodological interventions to understand and control its spread. In particular, The ability to effectively retrace its transmission pathways in outbreaks remains a major challenge. This is further exacerbated by our limited understanding of its underlying evolutionary mechanism. Using NGS whole-genome data, we determined whether inter- and intra-host diversity coupled with bottleneck analysis can retrace the pathway of viral transmission in two epidemiologically well characterised nosocomial outbreaks in healthcare settings supported by phylogenetic analysis. Additionally, we assessed the mutational landscape, selection pressure and diversity of the identified variants. Our findings showed evidence of intrahost variant transmission and evolution of SARS-CoV-2 after infection These observations were consistent with the results from the bottleneck analysis suggesting that certain intrahost variants in this study could have been transmitted to recipients. In both outbreaks, we observed iSNVs and SNVs shared by putative source-recipients pairs. Majority of the observed iSNVs were positioned in the S and ORF1ab region. AG, CT and TC nucleotide changes were enriched across SARS-COV-2 genome. Moreover, SARS-COV-2 genome had limited diversity in some loci while being highly conserved in others. Overall, Our findings show that the synergistic effect of combining withinhost diversity and bottleneck estimations greatly enhances resolution of transmission events in Sars-Cov-2 outbreaks. They also provide insight into the genome diversity suggesting purifying selection may be involved in the transmission. Together these results will help in developing strategies to elucidate transmission events and curtail the spread of Sars-Cov-2

SARS-CoV-2 cell-to-cell spread occurs rapidly and is insensitive to antibody neutralization

Viruses increase the efficiency of close-range transmission between cells by manipulating cellular physiology and behavior, and SARS-CoV-2 uses cell fusion as one mechanism for cell-to-cell spread. Here we visualized infection using time-lapse microscopy of a human lung cell line and used live virus neutralization to determine the sensitivity of SARS-CoV-2 cell-to-cell spread to neutralizing antibodies. SARS-CoV-2 infection rapidly led to cell fusion, forming multinucleated cells with clustered nuclei which started to be detected at 6h post-infection. To compare sensitivity of cell-to-cell spread to neutralization, we infected either with cell-free virus or with single infected cells expressing on their surface the SARS-CoV-2 spike protein. We tested two variants of SARS-CoV-2: B.1.117 containing only the D614G substitution, and the escape variant B.1.351. We used the much smaller area of single infected cells relative to infection foci to exclude any input infected cells which did not lead to transmission. The monoclonal antibody and convalescent plasma we tested neutralized cell-free SARS-CoV-2, with the exception of B.1.351 virus, which was poorly neutralized with plasma from non-B.1.351 infections. In contrast, cell-to-cell spread of SARS-CoV-2 showed no sensitivity to monoclonal antibody or convalescent plasma neutralization. These observations suggest that, once cells are infected, SARS-CoV-2 may be more difficult to neutralize in cell types and anatomical compartments permissive for cell-to-cell spread.

SARS-CoV-2 Genetic diversity and lineage dynamics of in Egypt

COVID-19 was first diagnosed in Egypt on 14 February 2020. By the end of November 2021, over 333,840 cases and 18,832 deaths had been reported. As part of national genomic surveillance, 1,027 SARS-CoV-2 near whole-genomes had been generated and published by the end of May 2021. Here we describe the genomic epidemiology of SARS-CoV-2 in Egypt over this period using a subset of 976 high-quality Egyptian genomes analysed together with a representative set of global sequences within a phylogenetic framework. We show that a single lineage, C.36, introduced early in the pandemic was responsible for most cases in Egypt. Furthermore, we show that to remain dominant in the face of mounting immunity from previous infection and vaccination, this lineage evolved into various sub-lineages acquiring several mutations known to confer adaptive advantage and pathogenic properties. These results highlight the value of continuous genomic surveillance in regions where VOCs are not predominant and enforcement of public health measures to prevent expansion of existing lineages.

Management and containment of a SARS-CoV-2 Beta variant outbreak at the Malawi University of Science and Technology

Outbreaks of COVID at university campuses can spread rapidly and threaten the broader community. We describe the management of an outbreak at a Malawian university in April-May 2021 during Malawis second wave. Classes were suspended following detection of infections by routine testing and campus-wide PCR mass testing was conducted. Fifty seven cases were recorded, 55 among students, two among staff. Classes resumed 28 days after suspension following two weeks without cases. Just 6.3% of full-time staff and 87.4% of outsourced staff tested while 65% of students at the main campus and 74% at the extension campus were tested. Final year students had significantly higher positivity and lower testing coverage compared to freshmen. All viruses sequenced were beta variant and at least four separate virus introductions onto campus were observed. These findings are useful for development of campus outbreak responses and indicate the need to emphasize staff, males and senior students in testing. Article Summary LineSuccessful management of a campus outbreak using test trace and isolate approach with resumption within a month following suspension of all in-person classes. Trends in voluntary testing by gender, age and year of study that can help in formation of future management approaches.

Immunogenicity of the Ad26.CoV2.S vaccine in people living with HIV

BackgroundPeople living with HIV (PLWH) have been reported to have an increased risk of more severe COVID-19 disease outcome and an increased risk of death relative to HIV-uninfected individuals. Here we assessed the ability of the Johnson and Johnson Ad26.CoV2.S vaccine to elicit neutralizing antibodies to the Delta variant in PLWH relative to HIV-uninfected individuals. We also compared the neutralization after vaccination to neutralization elicited by SARS-CoV-2 infection only in HIV-uninfected, suppressed HIV PLWH, and PLWH with detectable HIV viremia. MethodsWe enrolled 26 PLWH and 73 HIV-uninfected participants from the SISONKE phase 3b open label South African clinical trial of the Ad26.CoV2.S vaccine in health care workers (HCW). Enrollment was a median 56 days (range 19-98 days) post-vaccination and PLWH in this group had well controlled HIV infection. We also enrolled unvaccinated participants previously infected with SARS-CoV-2. This group consisted of 34 PLWH and 28 HIV-uninfected individuals. 10 of the 34 (29%) SARS-CoV-2 infected only PLWH had detectable HIV viremia. We used records of a positive SARS-CoV-2 qPCR result, or when a positive result was absent, testing for SARS-CoV-2 nucleocapsid antibodies, to determine which vaccinated participants were SARS-CoV-2 infected prior to vaccination. Neutralization capacity was assessed using participant plasma in a live virus neutralization assay of the Delta SARS-CoV-2 variant currently dominating infections in South Africa. This study was approved by the Biomedical Research Ethics Committee at the University of KwaZulu-Natal (reference BREC/00001275/2020). FindingsThe majority (68%) of Ad26.CoV2.S vaccinated HCW were found to be previously infected with SARS-CoV-2. In this group, Delta variant neutralization was 9-fold higher compared to the infected only group (GMT=306 versus 36, p<0.0001) and 26-fold higher relative to the vaccinated only group (GMT=12, p<0.0001). No significant difference in Delta variant neutralization capacity was observed in vaccinated and previously SARS-CoV-2 infected PLWH relative to vaccinated and previously SARS-CoV-2 infected, HIV-uninfected participants (GMT=307 for HIV-uninfected, 300 for PLWH, p=0.95). SARS-CoV-2 infected, unvaccinated PLWH showed 7-fold reduced neutralization of the Delta variant relative to HIV-uninfected participants (GMT=105 for HIV-uninfected, 15 for PLWH, p=0.001). There was a higher frequency of non-responders in PLWH relative to HIV-uninfected participants in the SARS-CoV-2 infected unvaccinated group (27% versus 0%, p=0.0029) and 60% of HIV viremic versus 13% of HIV suppressed PLWH were non-responders (p=0.0088). In contrast, the frequency of non-responders was low in the vaccinated/infected group, and similar between HIV-uninfected and PLWH. Vaccinated only participants showed a low neutralization of the Delta variant, with a stronger response in PLWH (GMT=6 for HIV-uninfected, 73 for PLWH, p=0.02). InterpretationThe neutralization response of the Delta variant following Ad26.CoV2.S vaccination in PLWH with well controlled HIV was not inferior to HIV-uninfected study participants. In SARS-CoV-2 infected and non-vaccinated participants, the presence of HIV infection reduced the neutralization response to SARS-CoV-2 infection, and this effect was strongest in PLWH with detectable HIV viremia FundingSouth African Medical Research Council, The Bill & Melinda Gates Foundation.

Reduced amplification efficiency of the RNA-dependent-RNA-polymerase (RdRp) target enables tracking of the Delta SARS-CoV-2 variant using routine diagnostic tests

Routine SARS-CoV-2 surveillance in the Western Cape region of South Africa (January-August 2021) found a reduced PCR amplification efficiency of the RdRp gene target of the Seegene, Allplex 2019-nCoV diagnostic assay when detecting the Delta variant. We propose that this can be used as a surrogate for variant detection.

Divergence of delta and beta variants and SARS-CoV-2 evolved in prolonged infection into distinct serological phenotypes

Characterizing SARS-CoV-2 evolution in specific geographies may help predict the properties of variants coming from these regions. We mapped neutralization of a SARS-CoV-2 strain that evolved over 6 months from the ancestral virus in a person with advanced HIV disease. Infection was before the emergence of the Beta variant first identified in South Africa, and the Delta variant. We compared early and late evolved virus to the ancestral, Beta, Alpha, and Delta viruses and tested against convalescent plasma from ancestral, Beta, and Delta infections. Early virus was similar to ancestral, whereas late virus was similar to Beta, exhibiting vaccine escape and, despite pre-dating Delta, strong escape of Delta-elicited neutralization. This example is consistent with the notion that variants arising in immune-compromised hosts, including those with advanced HIV disease, may evolve immune escape of vaccines and enhanced escape of Delta immunity, with implications for vaccine breakthrough and reinfections. HighlightsO_LIA prolonged ancestral SARS-CoV-2 infection pre-dating the emergence of Beta and Delta resulted in evolution of a Beta-like serological phenotype C_LIO_LISerological phenotype includes strong escape from Delta infection elicited immunity, intermediate escape from ancestral virus immunity, and weak escape from Beta immunity C_LIO_LIEvolved virus showed substantial but incomplete escape from antibodies elicited by BNT162b2 vaccination C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/21263564v2_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@1194bfdorg.highwire.dtl.DTLVardef@1cbe318org.highwire.dtl.DTLVardef@aa74f8org.highwire.dtl.DTLVardef@e57969_HPS_FORMAT_FIGEXP M_FIG C_FIG

A Novel and Expanding SARS-CoV-2 Variant, B.1.1.318, dominates infections in Mauritius

Mauritius, a small island in the Indian Ocean, has had a unique experience of the SARS-CoV-2 pandemic. In March 2020, Mauritius endured a small first wave and quickly implemented control measures which allowed elimination of local transmission of SARS-CoV-2. When borders to the island reopened, it was accompanied by mandatory quarantine and testing of incoming passengers to avoid reintroduction of the virus into the community. As variants of concern (VOCs) emerged elsewhere in the world, Mauritius began using genomic surveillance to keep track of quarantined cases of these variants. In March 2021, another local outbreak occurred, and sequencing was used to investigate this new wave of local infections. Here, we analyze 154 SARS-CoV-2 viral genomes from Mauritius, which represent 12% of all the infections seem in Mauritius, these were both from specimens of incoming passengers before March 2021 and those of cases during the second wave. Our findings indicate that despite the presence of known VOCs Beta (B.1.351) and Alpha (B.1.1.7) among quarantined passengers, the second wave of local SARS-CoV-2 infections in Mauritius was caused by a single introduction and dominant circulation of the B.1.1.318 virus. The B.1.1.318 variant is characterized by fourteen non-synonymous mutations in the S-gene, with five encoded amino acid substitutions (T95I, E484K, D614G, P681H, D796H) and one deletion (Y144del) in the Spike glycoprotein. This variant seems to be increasing in prevalence and it is now present in 34 countries. This study highlights that despite having stopped the introduction of more transmissible VOCs by travel quarantines, a single undetected introduction of a B.1.1.318 lineage virus was enough to initiate a large local outbreak in Mauritius and demonstrated the need for continuous genomic surveillance to fully inform public health decisions.

Loss of recognition of SARS-CoV-2 B.1.351 variant spike epitopes but overall preservation of T cell immunity

SARS-CoV-2 variants have emerged that escape neutralization and potentially impact vaccine efficacy. T cell responses play a role in protection from reinfection and severe disease, but the potential for spike mutations to affect T cell immunity is poorly studied. We assessed both neutralizing antibody and T cell responses in 44 South African COVID-19 patients infected either with B.1.351, now dominant in South Africa, or infected prior to its emergence ( first wave), to provide an overall measure of immune evasion. We show for the first time that robust spike-specific CD4 and CD8 T cell responses were detectable in B.1.351-infected patients, similar to first wave patients. Using peptides spanning only the B.1.351 mutated regions, we identified CD4 T cell responses targeting the wild type peptides in 12/22 (54.5%) first wave patients, all of whom failed to recognize corresponding B.1.351-mutated peptides (p=0.0005). However, responses to the mutated regions formed only a small proportion (15.7%) of the overall CD4 response, and few patients (3/44) mounted CD8 responses that targeted the mutated regions. First wave patients showed a 12.7 fold reduction in plasma neutralization of B.1.351. This study shows that despite loss of recognition of immunodominant CD4 epitope(s), overall CD4 and CD8 T cell responses to B.1.351 are preserved. These observations may explain why, despite substantial loss of neutralizing antibody activity against B.1.351, several vaccines have retained the ability to protect against severe COVID-19 disease. One Sentence SummaryT cell immunity to SARS-CoV-2 B.1.351 is preserved despite some loss of variant epitope recognition by CD4 T cells.

Persistent SARS-CoV-2 infection and intra-host evolution in association with advanced HIV infection

While most people effectively clear SARS-CoV-2, there are several reports of prolonged infection in immunosuppressed individuals. Here we present a case of prolonged infection of greater than 6 months with shedding of high titter SARS-CoV-2 in an individual with advanced HIV and antiretroviral treatment failure. Through whole genome sequencing at multiple time-points, we demonstrate the early emergence of the E484K substitution associated with escape from neutralizing antibodies, followed by other escape mutations and the N501Y substitution found in most variants of concern. This provides support to the hypothesis of intra-host evolution as one mechanism for the emergence of SARS-CoV-2 variants with immune evasion properties.

Naturally-acquired immunity in Syrian Golden Hamsters provides protection from re-exposure to emerging heterosubtypic SARS-CoV-2 variants B.1.1.7 and B.1.351

The ability of acquired immune responses against SARS-CoV-2 to protect after subsequent exposure to emerging variants of concern (VOC) such as B1.1.7 and B1.351 is currently of high significance. Here, we use a hamster model of COVID-19 to show that prior infection with a strain representative of the original circulating lineage B of SARS-CoV-2 induces protection from clinical signs upon subsequent challenge with either B1.1.7 or B1.351 viruses, which recently emerged in the UK and South Africa, respectively. The results indicate that these emergent VOC may be unlikely to cause disease in individuals that are already immune due to prior infection, and this has positive implications for overall levels of infection and COVID-19 disease.

SARS-CoV-2 501Y.V2 (B.1.351) elicits cross-reactive neutralizing antibodies

Neutralization escape by SARS-CoV-2 variants, as has been observed in the 501Y.V2 (B.1.351) variant, has impacted the efficacy of first generation COVID-19 vaccines. Here, the antibody response to the 501Y.V2 variant was examined in a cohort of patients hospitalized with COVID-19 in early 2021 - when over 90% of infections in South Africa were attributed to 501Y.V2. Robust binding and neutralizing antibody titers to the 501Y.V2 variant were detected and these binding antibodies showed high levels of cross-reactivity for the original variant, from the first wave. In contrast to an earlier study where sera from individuals infected with the original variant showed dramatically reduced potency against 501Y.V2, sera from 501Y.V2-infected patients maintained good cross-reactivity against viruses from the first wave. Furthermore, sera from 501Y.V2-infected patients also neutralized the 501Y.V3 (P.1) variant first described in Brazil, and now circulating globally. Collectively these data suggest that the antibody response in patients infected with 501Y.V2 has a broad specificity and that vaccines designed with the 501Y.V2 sequence may elicit more cross-reactive responses.

Reduced antibody cross-reactivity following infection with B.1.1.7 than with parental SARS-CoV-2 strains

We examined the immunogenicity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant B.1.1.7 that arose in the United Kingdom and spread globally. Antibodies elicited by B.1.1.7 infection exhibited significantly reduced recognition and neutralisation of parental strains or of the South Africa B.1.351 variant, than of the infecting variant. The drop in cross-reactivity was more pronounced following B.1.1.7 than parental strain infection, indicating asymmetric heterotypic immunity induced by SARS-CoV-2 variants.

SARS-CoV-2 501Y.V2 escapes neutralization by South African COVID-19 donor plasma

SARS-CoV-2 501Y.V2 (B.1.351), a novel lineage of coronavirus causing COVID-19, contains substitutions in two immunodominant domains of the spike protein. Here, we show that pseudovirus expressing 501Y.V2 spike protein completely escapes three classes of therapeutically relevant antibodies. This pseudovirus also exhibits substantial to complete escape from neutralization, but not binding, by convalescent plasma. These data highlight the prospect of reinfection with antigenically distinct variants and foreshadows reduced efficacy of spike-based vaccines.

Global Expansion of SARS-CoV-2 Variants of Concern: Dispersal Patterns and Influence of Air Travel

In many regions of the world, the Alpha, Beta and Gamma SARS-CoV-2 Variants of Concern (VOCs) co-circulated during 2020-21 and fueled waves of infections. During 2021, these variants were almost completely displaced by the Delta variant, causing a third wave of infections worldwide. This phenomenon of global viral lineage displacement was observed again in late 2021, when the Omicron variant disseminated globally. In this study, we use phylogenetic and phylogeographic methods to reconstruct the dispersal patterns of SARS-CoV-2 VOCs worldwide. We find that the source-sink dynamics of SARS-CoV-2 varied substantially by VOC, and identify countries that acted as global hubs of variant dissemination, while other countries became regional contributors to the export of specific variants. We demonstrate a declining role of presumed origin countries of VOCs to their global dispersal: we estimate that India contributed <15% of all global exports of Delta to other countries and South Africa <1-2% of all global Omicron exports globally. We further estimate that >80 countries had received introductions of Omicron BA.1 100 days after its inferred date of emergence, compared to just over 25 countries for the Alpha variant. This increased speed of global dissemination was associated with a rebound in air travel volume prior to Omicron emergence in addition to the higher transmissibility of Omicron relative to Alpha. Our study highlights the importance of global and regional hubs in VOC dispersal, and the speed at which highly transmissible variants disseminate through these hubs, even before their detection and characterization through genomic surveillance. HighlightsO_LIGlobal phylogenetic analysis reveals relationship between air travel and speed of dispersal of SARS-CoV-2 variants of concern (VOCs) C_LIO_LIOmicron VOC spread to 5x more countries within 100 days of its emergence compared to all other VOCs C_LIO_LIOnward transmission and dissemination of VOCs Delta and Omicron was primarily from secondary hubs rather than initial country of detection during a time of increased global air travel C_LIO_LIAnalysis highlights highly connected countries identified as major global and regional exporters of VOCs C_LI