BackgroundSeveral past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts.MethodsHere we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed). We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event.ConclusionsWe find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015). We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001). All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings.

BackgroundAccurate antibody tests are essential to monitor the SARS-CoV-2 pandemic. Lateral flow immunoassays (LFIAs) can deliver testing at scale. However, reported performance varies, and sensitivity analyses have generally been conducted on serum from hospitalised patients. For use in community testing, evaluation of finger-prick self-tests, in non-hospitalised individuals, is required.MethodsSensitivity analysis was conducted on 276 non-hospitalised participants. All had tested positive for SARS-CoV-2 by reverse transcription PCR and were ≥21 days from symptom onset. In phase I, we evaluated five LFIAs in clinic (with finger prick) and laboratory (with blood and sera) in comparison to (1) PCR-confirmed infection and (2) presence of SARS-CoV-2 antibodies on two ‘in-house’ ELISAs. Specificity analysis was performed on 500 prepandemic sera. In phase II, six additional LFIAs were assessed with serum.Findings95% (95% CI 92.2% to 97.3%) of the infected cohort had detectable antibodies on at least one ELISA. LFIA sensitivity was variable, but significantly inferior to ELISA in 8 out of 11 assessed. Of LFIAs assessed in both clinic and laboratory, finger-prick self-test sensitivity varied from 21% to 92% versus PCR-confirmed cases and from 22% to 96% versus composite ELISA positives. Concordance between finger-prick and serum testing was at best moderate (kappa 0.56) and, at worst, slight (kappa 0.13). All LFIAs had high specificity (97.2%–99.8%).InterpretationLFIA sensitivity and sample concordance is variable, highlighting the importance of evaluations in setting of intended use. This rigorous approach to LFIA evaluation identified a test with high specificity (98.6% (95%CI 97.1% to 99.4%)), moderate sensitivity (84.4% with finger prick (95% CI 70.5% to 93.5%)) and moderate concordance, suitable for seroprevalence surveys.

It is unclear what role the experimental drug and convalescent plasma had in the recovery of these patients. Prospective clinical trials are needed to delineate the role of investigational therapies in the care of patients with EVD.

kill' strategy, for future trials significant enhancement of both 'kick' and 'kill' agents will be required. Research in context panel Evidence before this study This randomised clinical trial was designed to test the concept of 'kick and kill' as a strategy to achieve a cure for HIV infection. Prior to this study, there was evidence from in vitro and single arm clinical studies that the histone deacetylase inhibitor (HDACi) class of drugs could induce viral transcription from latently infected cells, potentially creating a target for the immune system. In conjunction with this 'kick' to the latent HIV reservoir there was evidence that T cell immunitywhich determines HIV disease progression-could be enhanced through vaccination-induced responses, providing the 'kill'. Although the strategy of 'kick and kill' looked promising, there had been no powered RCTs to test it. Added value of the study RIVER tested 'kick and kill' using the HDACi vorinostat as the 'kick' combined with a vaccine strategy targeting conserved regions of the HIV genome. The vaccine aimed to produce T cells to kill latently-infected cells in which viral transcription had been induced by the HDACi. RIVER showed that the intervention was safe, with outstanding adherence to the complex trial protocol by the participants. However, even though there was evidence for both increased histone acetylation and potent vaccine-induced T-cell responses, the intervention did not confer any additional benefit on any measures of the HIV reservoir compared with antiretroviral therapy alone. Implications of all the available evidence. RIVER was the first RCT in treated recent HIV infection, and was not able to show any impact of 'kick and kill' on the primary outcome measure, or any marker of the HIV reservoir size. This is consistent with other studies which had tested HDACi alone. We did not, however, stop antiretroviral therapy in the RIVER trial participants, and future studies may include a treatment interruption as a further measure of impact. Whilst the RIVER trial suggests that this specific 'kick and kill' approach may not be an effective approach towards achieving HIV cure, the overall principle can not yet be dismissed, as more potent future interventions may have a greater impact.

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