| ObjectiveThis study focuses on the demand for healthcare resources demand in the context of the Corona Virus Disease 2019(COVID-19)pandemic and a transmission dynamics model was introduced to develop a scenario-based study.Under different scenarios of prevention and control intensities,proportion of population immunized by vaccination and asymptomatic infections,the key healthcare resources demand for clinical diagnosis and treatment,laboratory testing,epidemiological investigation were comprehensively assessed in the zone to analyze the challenges and preparation strategies for the imbalance between supply and demand of healthcare resources.This study aims to provide a reference for conducting healthcare resource demand assessment and preparation across locations.Methods1.Data collection and methods summaryFirst,the meaning of healthcare resources and related keywords were systematically teased out through the analysis of the published literature and professional opinions.Then a transmission dynamics model and resources demand assessment scenarios were constructed.The model was aimed to predict the number of present cases under each scenario.The consumption ratios between close contacts,asymptomatic infections,and confirmed patients and the laboratory testing,epidemiological prevention and control resources in our country were obtained by combining information from outbreak control documents,reports from mainstream media and professional opinions.Finally the number of healthcare resources demand in various scenarios were calculated,and they were compared with the actual related reserves in the equally developed regions of China,so as to evaluate the gap between supply and demand.R studio V3.6.3 software and the deSolve package were employed for modeling analysis,and Origin Lab 2019 and Excel 2010 were used for diagram drawing.2.Propagation dynamics model construction An expanded model was built to assess the demand for healthcare resources in a Chinese city with a population of 5 million residents.Based on the different status,mechanisms of transmission,and premise assumptions of infectious diseases,the SEIHR model was constructed by increasing the storage of confirmed patients(H)and introducing asymptomatic patients into I and H under the traditional SEIR.Mean absolute percentage error(MAPE)was used to conduct the model prediction error test.Considering the social conditions of low interventions and large amount of nucleic acid test in the early stage,there were contrast between the number of daily reported cases in Italy,obtained from https://ourworldindata.org/coronavirus,with the number of confirmed cases estimated by the model to verify its accuracy.Because of the lags between the infection,illness onset,and reporting as well,the curve from the start of the first reported inpatient episode in Italy to the announcement of the extended lockdown(Feb 24 to Mar 15,2020),during which the number of cases did not exceed the load of their healthcare system and with the outbreaks warning in China,was only fitted.3.Scenarios constructionScenario 1:COVID-19 pandemic with widespread spread within the community and a low proportion of asymptomatic infections,which was similar to the early epidemic situation in Wuhan in December 2019.Scenario 2:An outbreak in a local region with a low proportion of asymptomatic infections,which resembled the epidemic situation of Xinfadi in Beijing in June 2020.Scenario 3:An outbreak with a low proportion of asymptomatic patients and a high proportion of population immunized by vaccination for which the vaccine was listed.Scenario 4:A high proportion of asymptomatic appeared to be sporadic(for example,sporadic cold chain related cases in Qingdao,Shandong Province in September 2020).Scenario 5:The sporadic scenario under vaccination.Scenario 6:A severe widespread community transmission scenario due to significant reduction in NPIs at 10%of the immunized people by vaccination.Results1.Healthcare resources demand consist of three parts:(1)The human resources,the number of hospital beds(general ward,isolation ward,ICU)and medical equipment(ventilators oxygen equipment)demand,the number of personal protective equipment(PPE)of medical staff(protective clothing,isolation gown,N95 masks,gloves,isolation caps)were included in the clinical resources.(2)Laboratory testing human resources,equipment and PPE were included in the laboratory testing resources.(3)Epidemiological investigators,community prevention and control personnel,social volunteers and consumption of PPE were included in the epidemiological resources.2.Evaluation of outcomes for different scenariosResults of scenario 1 and scenario 2 showed that under the premise of the same proportion of asymptomatic infected individuals,effectiveness of NPIs,no immunized population by vaccination,achieving early detection,reporting,isolation and treatment of cases,can reduce the peak number of current infections by 85.0%.Both implementation of full member nucleic acid test,the need for specimen samplers,service guards at the sampling site was equal in peak,and the occupancy of other healthcare resources was effectively reduced.In case of spread and outbreaks within communities,the acute demand for healthcare resources,especially human resources,exceeded the capacity of existing resource reserves in the region and requires human and material assistance from other regions.The results from scenarios 2 and 3 showed that under the premise of equal proportions of asymptomatic infections,the number of cases with strictly efficacious NPIs without COVID-19 vaccination,was largely consistent with the number of cases with 50%of immunized population by vaccination and appropriately reduced the NPIs efficacy.Under these conditions,a 4.1-32.4 folds increase in laboratory testing and epidemiological prevention and control resources would be achieved through the implementation of total persons nucleic acid testing.The results from scenarios 3,4 and 5 indicated that when the proportion of asymptomatic infected persons reached to 80%and the proportion of people immunized by vaccination maintained 10%,the duration and the occupancy of health care resources would be as long as one year,even with the small size of cases sporadic.Only an increase in the proportion of people immunized by vaccination would lead to the rapid culling of outbreaks in the short term.The results from scenarios 4,5,and 6 showed that with a higher proportion of asymptomatic infected individuals,the NPIs cannot be rapidly relaxed in the short term under the low proportion of population immunized by vaccination.If the effectiveness of NPIs was substantially reduced,there would be a severe intracommunity epidemic.Then the maximum number of present patients occupied 25%of the regional population.Ultimately,it would lead to a serious shortage of healthcare resources and even the collapse of the medical and health delivery system.Conclusions1.In the early stage of epidemic development or when the number of imported cases is limited,the implementation of containment,defense and suppression strategies can effectively reduce the demand for healthcare resources.If the NPIs are more active and implemented jointly,the prevention and control effect will be better,and even the epidemic can be successfully put out in a short time,without impact on the medical system.During the COVID-19 pandemic,it still should to insist on early detection,early reporting,early isolation and early treatment in the disease prevention and control.2.When the proportion of asymptomatic infection is large but that of proportion of population immunized by vaccination is only 10%,the measures should not be excessively relaxed.When the population immunized by vaccination accounts for 50%of the regional population,the effectiveness of NPIs could be appropriately adjusted and reduced from the perspective of economic development and public acceptability.3.In the event of community transmission and outbreak,the demand surge for healthcare resources,especially human resources,exceeds the carrying capacity of existing regional resource reserves.At present,China still needs to reserve medical and health manpower,especially infectious disease professionals,to improve the proportion of infectious disease beds,so as to cope with the unpredictable new wave of serious epidemic in China.4.The challenge of nucleic acid test to human resources and the necessity of implementation deserve to be studied.Whether nucleic acid test should be carried out in the outbreak should be comprehensively evaluated in combination with the resources reserve and economic development of the region.5.The implementation of NPIs,expansion of vaccine capacity,better distribution of vaccine and increase of COVID-19 vaccine coverage rate can alleviate the impact of health resource demand caused by the pandemic to a certain extent.6.In case of serious community transmission and short supply of healthcare resources,alternative supply of resources should be considered.For example,when the ventilator is insufficient,respiratory support and prone position are recommended to use to improve oxygenation and drain airway secretions.When there is a shortage of professionals,we should train the staff of relevant infection department and critical care department to get technical assistance in a short time.Complete vaccine storage and vaccination deserve to be done as well. |
