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LitCovid-PubTator

Id Subject Object Predicate Lexical cue tao:has_database_id
87 2113-2122 Disease denotes infection MESH:D007239

LitCovid-sentences

Id Subject Object Predicate Lexical cue
T130 0-7 Sentence denotes Results
T131 8-113 Sentence denotes We found that, as of April 11, 2020, physical distancing had considerably reduced the contact rate in BC.
T132 114-364 Sentence denotes We estimated that individuals practising physical distancing experienced approximately 0.22 (0.11–0.34 90% CI [credible interval]) of their normal contact rate, which was below the critical threshold (0.55; Fig 3; Figures E–H and Table C in S1 Text).
T133 365-533 Sentence denotes The model described the count data well, with reported cases showing a peak in late March, approximately two weeks after the initiation of distancing measures (Fig 3A).
T134 534-686 Sentence denotes The data were informative with respect to both main parameters with the posteriors distinctly different and more peaked than the priors (Fig 3B and 3D).
T135 687-812 Sentence denotes We used a fixed value of e, the fraction engaged in distancing; this choice was motivated by the survey and behavioural data.
T136 813-915 Sentence denotes If e were lower, the estimated strength of distancing would be higher to achieve the same case counts.
T137 916-1055 Sentence denotes We found this trade-off analytically using the basic reproduction number for the full model (Supplemental Methods and Figure A in S1 Text).
T138 1056-1229 Sentence denotes Fig 3 (A) Observed and estimated case counts, (C) estimated prevalence, and posterior estimates for (B) R0b and (D) fraction of normal contacts (f2) among those distancing.
T139 1230-1366 Sentence denotes These projections do not account for introduced cases from other jurisdictions and they assume that distancing measures remain in place.
T140 1367-1497 Sentence denotes The fraction of normal contacts is the model’s portion of contacts that remain among those who are engaged in physical distancing.
T141 1498-1638 Sentence denotes In panel A, the blue line represents the posterior mean and the shaded ribbons represent 50% and 90% credible intervals on new observations.
T142 1639-1688 Sentence denotes Dots and black lines represent the reported data.
T143 1689-1726 Sentence denotes Grey region indicates the projection.
T144 1727-1788 Sentence denotes In panel C, lines represent example draws from the posterior.
T145 1789-1856 Sentence denotes In panels B and D, priors are shown in grey and posteriors in blue.
T146 1857-2004 Sentence denotes In panel D, the dashed vertical line denotes the threshold above which an exponential increase in prevalence is expected (see Figure J in S1 Text).
T147 2005-2010 Sentence denotes Note:
T148 2011-2197 Sentence denotes Model prevalence depends on assumptions about underestimation, incubation period, and the duration of infection, none of which we can estimate well from these data (Figure M in S1 Text).
T149 2198-2264 Sentence denotes Much higher values of the prevalence are consistent with our data.
T150 2265-2631 Sentence denotes We found that with a shorter incubation period and duration of infectiousness, a lower reproduction number would fit the same overall growth rate, and conversely if the infectious duration and serial interval were longer, a higher reproduction number would be required but the fit to data would be similar (Figure K in S1 Text); this relationship is well known [35].
T151 2632-2742 Sentence denotes The conclusion that distancing measures reduced contact is robust to these alternatives (Figure K in S1 Text).
T152 2743-2952 Sentence denotes The model depends on the fraction engaged in distancing, but not strongly on the rates ud and ur; Figure L in S1 Text illustrates that we obtained the same results with these rates increased by a factor of 10.
T153 2953-3261 Sentence denotes We also explored the robustness to the unknown underestimation fractions (Figure M in S1 Text), and a random walk pattern in the fraction of cases sampled (Figure N in S1 Text); again, the data are consistent with a range of underestimation fractions, but the conclusion about the contact fraction is robust.
T154 3262-3709 Sentence denotes Our estimates suggest that, as of April 11, 2020, some relaxation of current distancing measures in BC would have been possible without bringing the growth rate above zero, but if measures were relaxed too much (in the absence of monitoring and re-starting measures), the prevalence and case counts would begin to increase exponentially (Fig 4A and 4B), reaching high levels by June 2020 if distancing were to cease entirely (Figure I in S1 Text).
T155 3710-3874 Sentence denotes These are illustrative scenarios only; public health responses with renewed or revised measures would likely be put in place rapidly were such rises to be observed.
T156 3875-3978 Sentence denotes The speed of growth depends on how close the system is to the epidemic threshold (Figure J in S1 Text).
T157 3979-4167 Sentence denotes If strong enough measures are not maintained, the model predicts a range of possible epidemic curves (Figure I in S1 Text) consistent with simple and complex published models [11, 12, 14].
T158 4168-4217 Sentence denotes Fig 4 Scenarios of relaxing distancing measures.
T159 4218-4434 Sentence denotes Distancing measures are relaxed to (A) 60% (A) and (B) 80% levels of normal contacts and exponential growth is observed at moderate and rapid rates. (C, D) Two scenarios of cycling between physical distancing levels.
T160 4435-4586 Sentence denotes Here, the percentage of normal contacts alternates between 80% (dark-grey shading) and 22% (light-grey shading) at (C) 3-week and (D) 4-week intervals.
T161 4587-4680 Sentence denotes Reducing contacts to 22% of normal is approximately the level estimated by our model (Fig 3).
T162 4681-4758 Sentence denotes Note the lag between changes in physical distancing and reported case counts.
T163 4759-4821 Sentence denotes Figure description is otherwise the same as for Fig 3A and 3C.
T164 4822-4997 Sentence denotes There has been interest in relaxing distancing measures and re-introducing them when a threshold has been reached, such as when intensive care capacity is nearly reached [36].
T165 4998-5145 Sentence denotes We did not explore a dynamic trigger, but did explore the behaviour when distancing measures are introduced and relaxed repeatedly (Fig 4C and 4D).
T166 5146-5354 Sentence denotes If the relaxation period is such that the outbreak remains contained throughout (with an effective reproduction number less than one), then the prevalence would decline at alternating faster and slower rates.
T167 5355-5543 Sentence denotes In a scenario of switching between the current mean estimate (22% of normal contacts) and 80% of normal contacts, reported cases rise, lagging the relaxation of distancing (Fig 4C and 4D).
T168 5544-5798 Sentence denotes Illustrative simulations in which distancing alternates every three or four weeks allows an overall continued decline; however, the longer the period of relaxation, the more the prevalence is able to rise in between periods of distancing (Fig 4C and 4D).
T169 5799-5996 Sentence denotes Control of delayed feedback systems is challenging [37], and ideally if a dynamic trigger such as reported cases or ICU admissions were to be used, monitoring would need to be as rapid as possible.
T170 5997-6116 Sentence denotes Monitoring of distancing behaviour and population contact patterns would be important, in addition to monitoring cases.
T171 6117-6423 Sentence denotes We estimated the fraction of normal contact rate in five additional jurisdictions as of May 7, 2020 (Fig 5), and give numerical results as the median (and 90% CI) of the “contact ratio”: the ratio of the fraction of normal contacts to the threshold (above which prevalence increases) for each jurisdiction.
T172 6424-6720 Sentence denotes We found that while New York had a high peak in reported cases, overall control there was strong as of May 7 and there may have been room to relax distancing measures while remaining below the threshold above which cases would be expected to increase, since the contact ratio is 0.60 (0.43–0.74).
T173 6721-6829 Sentence denotes We estimated contact ratios of 0.86 (0.76–0.96) for Florida and 0.84 (0.79–0.90) for Washington as of May 7.
T174 6830-6969 Sentence denotes These are not far below 1.0, and so any re-opening or relaxation of distancing measures would be expected to result in rising case numbers.
T175 6970-7322 Sentence denotes In contrast, while some areas in California experienced strong distancing and mobility data suggest movement on par with Florida, New York, and Washington (Fig 5F), overall case counts in California had not declined as of May 7, and our model estimated that contacts were exceeding the critical threshold on average (contact ratio of 1.15 [1.07–1.23]).
T176 7323-7527 Sentence denotes In contrast, New Zealand had extremely effective control measures and we estimated that nearly all contacts were removed among those distancing as of May 6, 2020, with a contact ratio of 0.22 (0.11–0.34).
T177 7528-7660 Sentence denotes This left considerable room for re-opening (in concert with careful border measures and continued contact tracing and case finding).
T178 7661-7786 Sentence denotes Fig 5 Observed and estimated case counts for (A) New York, (B) Florida, (C) Washington, (D) California, and (E) New Zealand.
T179 7787-7910 Sentence denotes Solid curves represent the posterior means and shaded ribbons represent 50% and 90% credible intervals of estimated counts.
T180 7911-7960 Sentence denotes Dots and black lines represent the reported data.
T181 7961-8285 Sentence denotes Inset histograms show the posterior distributions of the fraction of normal contacts (f2), with the vertical lines denoting the threshold above which an exponential increase in prevalence is expected (as in Fig 3D). (F) Reduction in movement from Google mobility transit-station data [21] colour-coded for each jurisdiction.
T182 8286-8377 Sentence denotes Thin lines are raw data; thick lines are smoothed values from a generalized additive model.
T183 8378-8494 Sentence denotes See Table B and Supplemental Methods in S1 Text for details on the regional modelling parameters and initialization.