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Vaccination against the SARS-CoV-2 virus is critical to control the pandemic. Randomized clinical trials demonstrated efficacy of the single-dose Ad26.COV2.S COVID-19 vaccine, but data on longer-term protection in clinical practice and effectiveness against variants are needed.To assess the association between receiving the Ad26.COV2.S vaccine and COVID-19-related infections and hospitalizations before and during the Delta variant surge.This cohort study included adults aged 18 years and older who were newly Ad26.COV2.S-vaccinated matched to as many as 10 unvaccinated individuals by date, location, age, sex, and comorbidity index. This was followed by 1:4 propensity score matching on COVID-19 risk factors. Data were collected from US insurance claims data from March 1, 2020, through August 31, 2021.Vaccination with Ad26.COV2.S vs no vaccination.Vaccine effectiveness (VE) was estimated for recorded COVID-19 infection and COVID-19-related hospitalization, nationwide and in subgroups by age, high-risk factors, calendar time, and states with high incidences of the Delta variant. VE estimates were corrected for underrecording of vaccinations in insurance data.Among 422 034 vaccinated individuals (mean [SD] age, 54.7 [17.4] years; 236 437 [56.0%] women) and 1 645 397 matched unvaccinated individuals (mean [SD] age, 54.5 [17.5] years; 922 937 [56.1%] women), VE was 76% (95% CI, 75%-77%) for COVID-19 infections and 81% (95% CI, 78%-82%) for COVID-19-related hospitalizations. VE was stable for at least 180 days after vaccination and over calendar time. Among states with high Delta variant incidence, VE during June to August 2021 was 74% (95% CI, 71%-77%) for infections and 81% (95% CI, 75%-86%) for hospitalizations. VE for COVID-19 was higher in individuals younger than 65 years (78%; 95% CI, 77%-79%) and lower in immunocompromised patients (64%; 95% CI, 59%-68%). All estimates were corrected for vaccination underrecording; uncorrected VE, which served as a lower bound, was 66% (95% CI, 64%-67%) for any recorded COVID-19 infection and 72% (95% CI, 69%-74%) for COVID-19-related hospitalization.This cohort study in US clinical practice showed stable VE of Ad26.COV2.S for at least 6 months before as well as during the time the Delta variant emerged and became dominant.

ImportanceVaccination against the SARS-CoV-2 virus is critical to control the pandemic. Randomized trials demonstrated efficacy of the single-dose Ad26.COV2.S COVID vaccine but data on longer-term protection in clinical practice and effectiveness against variants are needed.ObjectiveTo assess the effectiveness of Ad26.COV2.S in preventing COVID infections and COVID-related hospitalizations in clinical practice, the longer-term stability of its protective effect and effectiveness against Delta variants.DesignCohort study of newly Ad26.COV2.S-vaccinated and unvaccinated individuals.SettingU.S. insurance claims data through July 2021.ParticipantsIndividuals 18 years and older newly vaccinated with Ad26.COV2.S and up to 10 unvaccinated individuals matched exactly by age, sex, date, location, comorbidity index plus 17 COVID-19 risk factors via propensity score (PS) matching.InterventionVaccination with Ad26.COV2.S versus no vaccination.Main outcomesWe estimated vaccine effectiveness (VE) for observed COVID-19 infection and COVID-19-related hospitalization, nationwide and stratified by age, immunocompromised status, calendar time, and states with high incidence of the Delta variant. We corrected VE estimates for under-recording of vaccinations in insurance data.ResultsAmong 390,517 vaccinated and 1,524,153 matched unvaccinated individuals, VE was 79% (95% CI, 77% to 80%) for COVID-19 and 81% (79% to 84%) for COVID-19-related hospitalizations. VE was stable over calendar time. Among states with high Delta variant incidence, VE during June/July 2021 was 78% (73% to 82%) for infections and 85% (73% to 91%) for hospitalizations. VE for COVID-19 was higher in individuals ConclusionsThese non-randomized data across U.S. clinical practices show high and stable vaccine effectiveness of Ad26.COV2.S over time before the Delta variant emerged to when the Delta variant was dominant.

Integrated analysis of data together with fit-for-purpose modelling can help in fast track maturation of opportunities. In 2012, an opportunity to increase oil by implementing waterflood was identified, and last year was further reviewed by Shell. An integrated approach helped the team to mature ten development wells within three months which were subsequently drilled and helped the operator to surpass their production targets. The field located in Western Desert, Egypt comprises of an Upper Cretaceous tidal channel system across four key reservoirs where sand thickness ranges between 2-15 m. Large uncertainties in reservoir extent, architecture and properties required the integration of data across multiple disciplines for identifying new development wells. It was recognized early on that the construction of full-field fine-scale static models would be time-consuming and hence a simplified fast-track approach was used for maturing the opportunity. Conceptual depositional models were built by integrating dipmeter data, image logs and core facies descriptions to understand the direction of continuity of tidal channels, tidal bars and mud flats. Net sand thickness maps were then constructed to represent the conceptual depositional model and integrated with the production behaviour of the wells. Production from historical wells drilled up to 2012 caused non-uniform pressure depletion across reservoirs. The pressure data from Modular Dynamic Tester (MDT), along with the production-injection history, was reviewed to identity both areal and vertical stratigraphically connected areas which were incorporated in the net sand maps. The constructed maps were quality checked with pressure and production data so as to validate the range of in-place volumes. Net sand maps, porosity maps and saturation models were combined to generate Hydrocarbon Pore Volume (HCPV) maps used to identify new well opportunities. Separate sector models were also constructed to evaluate the waterflood and to optimise the decision parameters like injector-producer spacing, injection rates, voidage replacement ratio and target reservoir pressure. A range of type curves were generated from Monte Carlo simulation runs for all key sub-surface uncertainties then was used to estimate the low, base and high case recoverable volumes for the identified well locations and patterns. The identified wells were drilled between February and August 2015 and helped increase production rates of the field by over 5,000 stb/d.A fit-for-purpose modelling using sand maps and connectivity maps can often greatly help in fast-tracking opportunity maturation and fine-scale detailed simulation modelling may not provide additional value.