Background:Little is known about stage 1 and 2 pressure injuries that are health care-acquired.We report incidence rates of health care-acquired stage 1 and stage 2 pressure injuries,and,estimate the excess length of ...Background:Little is known about stage 1 and 2 pressure injuries that are health care-acquired.We report incidence rates of health care-acquired stage 1 and stage 2 pressure injuries,and,estimate the excess length of stay using four competing analytic methods.We discuss the merits of the different approaches.Methods:We calculated monthly incidence rates for stage 1 and 2 health care-acquired pressure injuries occurring in a large Singapore acute care hospital.To estimate excess stay,we conducted unadjusted comparisons with a control cohort,performed linear regression and then generalized linear regression with a gamma distribution.Finally,we fitted a simple state-based model.The design for the cost attribution work was a retrospective matched cohort study.Results:Incidence rates in 2016 were 0.553%(95%confidence interval[CI]0.55,0.557)and 0.469%(95%CI 0.466,0.472)in 2017.For data censored at 60 days’maximum stay,the unadjusted comparisons showed the highest excess stay at 17.68(16.43-18.93)days and multi-state models showed the lowest at 1.22(0.19,2.23)days.Conclusions:Poor-quality methods for attribution of excess length of stay to pressure injury generate inflated estimates that could mislead decision makers.The findings from the multi-state model,which is an appropriate method,are plausible and illustrate the likely bed-days saved from lowering the risk of these events.Stage 1 and 2 pressure injuries are common and increase costs by prolonging the length of stay.There will be economic value investing in prevention.Using biased estimates of excess length of stay will overstate the potential value of prevention.展开更多
In this article, we establish the global asymptotic stability of a disease-free equilibrium and an endemic equilibrium of an SIRS epidemic model with a class of nonlin- ear incidence rates and distributed delays. By u...In this article, we establish the global asymptotic stability of a disease-free equilibrium and an endemic equilibrium of an SIRS epidemic model with a class of nonlin- ear incidence rates and distributed delays. By using strict monotonicity of the incidence function and constructing a Lyapunov functional, we obtain sufficient conditions under which the endemic equilibrium is globally asymptotically stable. When the nonlinear inci- dence rate is a saturated incidence rate, our result provides a new global stability condition for a small rate of immunity loss.展开更多
In this paper,an SEIR model with nonlinear incidence rates are studied.The basic reproduction number R_0 characterizes the disease transmission dynamics: if R_0≤ 1,the disease-free equilibrium is globally asymptotica...In this paper,an SEIR model with nonlinear incidence rates are studied.The basic reproduction number R_0 characterizes the disease transmission dynamics: if R_0≤ 1,the disease-free equilibrium is globally asymptotically stable and the disease always dies out,if R_0> 1 then there is a unique endemic equilibrium which is globally asymptotically stable and the disease persists.展开更多
Background: This study aimed to identify the role of human development index (HDI) in the incidence and mortality rates of breast cancer (BC) worldwide. Methods: Data on the age-standardized incidence and mortality ra...Background: This study aimed to identify the role of human development index (HDI) in the incidence and mortality rates of breast cancer (BC) worldwide. Methods: Data on the age-standardized incidence and mortality rates of BC for 184 countries were obtained from the GLOBOCAN. Data about the HDI and other indices were obtained from the World Bank Report 2013. Linear regression model was used for assessment the effect of HDI on BC occurrence rates. Results: In 2012, BCs were estimated to have affected a total of 1,671,149 individuals (crude rate: 47.8 per 100,000 individuals), and caused 521,907 deaths worldwide (crude rate: 14.7 per 100,000 individuals). Nearly half of total female BC cases (46.3%) with the highest risk of incidence (age-standardized Rate (ASR): 128 per 100,000) had occurred in very high HDI regions. The most proportion of the mortality burden was in low HDI and medium HDI areas. Linear regression analyses showed a direct significant correlation between the incidence of BC and HDI at the global level (B = 104.5, P < 0.001). The mortality rate of BC was not significantly associated with HDI (B = 3.26, P = 0.160). Conclusion: Our study showed that the burden of female BC is enormous in very high HDI and low HID regions. Targeted interventions have the ability to reduce this number significantly through resource-dependent interventions. Moreover, further reductions in mortality could be brought about by increasing access to curative treatment for patients with BC.展开更多
Objective: To explore the trends of incidence and mortality rates of stroke in Hanzhong rural population. Methods: Acting as the WHO MONICA project. Results: The incidence rate of stroke was 152.9/100 000. There was d...Objective: To explore the trends of incidence and mortality rates of stroke in Hanzhong rural population. Methods: Acting as the WHO MONICA project. Results: The incidence rate of stroke was 152.9/100 000. There was decline trend in male(P<0.05). The mortality rate of stroke was 115.9/100 000. There was no significant decline trend during 18-year period (P<0.05). The incidence and mortality rates of stroke of male were higher than those of female(P<0.05).The incidence and mortality rates were all increased with age(P<0.01). Conclusion: It must stick to the long- term prevention measures to decrease incidence rate, and improve the condition of medical treatment to reduce the mortality rate in rural population.展开更多
Introduction: Total knee arthroplasty (TKA) has been established as a transformative solution in the treatment of advanced degenerative diseases of the knee, such as osteoarthritis, rheumatoid arthritis, and posttraum...Introduction: Total knee arthroplasty (TKA) has been established as a transformative solution in the treatment of advanced degenerative diseases of the knee, such as osteoarthritis, rheumatoid arthritis, and posttraumatic arthritis. In this sense, TKA surgery, which seeks to replace the damaged joint with prosthetic components, has proven to be highly effective in relieving pain, improving joint function, and, ultimately, significantly increasing patients’ quality of life. The present study describes the TKA and revision knee arthroplasty (RKA) rates and, identifies the associated co morbidities in the Colombian context. Methods: A retrospective cohort study was carried out. It describes demographic and clinical characteristics between two groups of patients, TKA or RKA, and its association with mortality at 30 days, 90 days, or one year after the intervention. Results: The incidence rate of the population undergoing TKA was approximately 11.71 cases per 100,000 inhabitants. Furthermore, the incidence rate for revision knee arthroplasty (RKA) procedures in the same period was around 0.96 per 100,000 inhabitants. In both groups at 30 days postoperatively, a total mortality rate of 0.09%was recorded. When the follow-up was extended to 90 days, it increased to 0.15%;at one year postoperatively, it rose to 0.88%. Conclusion: Mortality after surgery was low in Colombia in 2019. Although RKA is a beneficial procedure, in certain circumstances, it was noted that it carries a higher risk compared to primary TKA. Our results emphasize the importance of careful evaluation of co morbidities and risk factors in patients undergoing these surgical procedures. The application of quality-of-life questionnaires should be considered in future studies on effectiveness and mortality for TKA and RKA in our country.展开更多
Objective Acute aortic dissection (AAD) is a catastrophic event with high early mortality rate, but to date, no data on the incidence of AAD in China's Mainland is available. This study aimed to estimate the inc...Objective Acute aortic dissection (AAD) is a catastrophic event with high early mortality rate, but to date, no data on the incidence of AAD in China's Mainland is available. This study aimed to estimate the incidence of AAD in China and characterize the clinical profile, management and in-hospital outcomes of this vascular event. Methods We used the China Health Insurance Research Data (the CHIRA Data) 2011 which comprises all inpatient hospital records (300,886) during the period of Jan. 1st 2011 to Dec. 31 2011 of 3,335,000 randomly sampled beneficiaries (1,718,500 men and 1,616,500 women) from 25 cities and counties in different economic-geographic regions of China's Mainland. Patients with acute aortic dissection were identified according to International Classification of Disease 10m Revision (ICD-10) of I71.0, The estimated incidence of AAD was calculated using the equation: estimated incidence = 2.0 × (40% × hospital admission rate) + 60% × hospital admission rate. Results The hospital admission rate was 2.0/100,000 (65/3,325,000, 95% CI: 1.2-2.8). The estimated annual incidence of AAD was 2.8/100,000 (95% CI: 1.9-3.6) and was higher in male than in female (3.7 vs. 1.5, P 〈 0.001). The mean age was 58.9 ± 13.4 years. During the mean hospital stay of 23 ±6 days, the overall in-hospital mortality was 13.9% (9/65). Conclusions Our study showed relatively lower but not negligible incidence and in-hospital mortality of AAD in the mainland of China. The mean age of patients with AAD in Chinese was younger than that reported by researches from west countries, while the male to female incidence ratio is similar to those reported by other studies.展开更多
This paper considers two differential infectivity(DI) epidemic models with a nonlinear incidence rate and constant or varying population size. The models exhibits two equilibria, namely., a disease-free equilibrium ...This paper considers two differential infectivity(DI) epidemic models with a nonlinear incidence rate and constant or varying population size. The models exhibits two equilibria, namely., a disease-free equilibrium O and a unique endemic equilibrium. If the basic reproductive number σ is below unity,O is globally stable and the disease always dies out. If σ〉1, O is unstable and the sufficient conditions for global stability of endemic equilibrium are derived. Moreover,when σ〈 1 ,the local or global asymptotical stability of endemic equilibrium for DI model with constant population size in n-dimensional or two-dimensional space is obtained.展开更多
A SIQS epidemic model with saturated incidence rate is studied. Two equilibrium points exist for the system, disease-free and endemic equilibrium. The stability of the disease-free equilibrium and endemic equilibrium ...A SIQS epidemic model with saturated incidence rate is studied. Two equilibrium points exist for the system, disease-free and endemic equilibrium. The stability of the disease-free equilibrium and endemic equilibrium exists when the basic reproduction number R0, is less or greater than unity respectively. The global stability of the disease-free and endemic equilibrium is proved using Lyapunov functions and Poincare-Bendixson theorem plus Dulac’s criterion respectively.展开更多
In a polluted environment, considering the biological population infected with a kind of disease and hunted by human beings, we formulate a nonautonomous SIR population-epidemic model with time-varying impulsive relea...In a polluted environment, considering the biological population infected with a kind of disease and hunted by human beings, we formulate a nonautonomous SIR population-epidemic model with time-varying impulsive release and general nonlinear incidence rate and investigate dynamical behaviors of the model. Under the reasonable assumptions, the sufficient conditions which guarantee the globally attractive of the disease-free periodic solution and the permanence of the infected fish are established, that is, the infected fish dies out if , whereas the disease persists if . To substantiate our theoretical results, extensive numerical simulations are performed for a hypothetical set of parameter values.展开更多
This study examined the change of reported incidence rate for viral hepatitis in Hubei province, China, between 2004 to 2010 to provide scientific evidence for viral hepatitis control. Reported viral hepatitis infecti...This study examined the change of reported incidence rate for viral hepatitis in Hubei province, China, between 2004 to 2010 to provide scientific evidence for viral hepatitis control. Reported viral hepatitis infection cases were queried from Centre for Disease Control of Hubei Province, China. The incidence of viral hepatitis A decreased steadily across the study period. Viral hepatitis B composed 85% of the viral hepatitis cases. When reported incidence rates for chronic hepatitis B increased, the rates of acute and unclassified cases dropped from 2005 to 2010. The reported viral hepatitis B incidence rate for males was around 1.5-2 times higher than for females. The average annual percentage change of reported viral hepatitis B incidence rates was 4%. The same index for viral hepatitis C was 28%. The reported viral hepatitis B incidence rate of people under 20 years old declined over the period. This decrease was mainly attributed to the recent implementation of vaccination plan. Reported incidence rate of viral hepatitis E also rose in those years. Having a better understanding on reported incidence rates of the present surveillance system is important for developing strategies for further prevention of viral hepatitis. In addition, the data showed that a surveillance system that differentiates new and former infected cases will be more effective in providing evidence for disease control.展开更多
Bovine tuberculosis(bTB)is a chronic zoonotic disease that is endemic in China.Current in-vitro tests for bTB are mainly based on blood assays.Collection of samples results in some stress to the sampled cattle and ass...Bovine tuberculosis(bTB)is a chronic zoonotic disease that is endemic in China.Current in-vitro tests for bTB are mainly based on blood assays.Collection of samples results in some stress to the sampled cattle and associated economic losses for the herd owner.This study was designed to investigate the relationship between milk and serum antibody tests for bTB in dairy cows using 85 cows with milk and corresponding blood samples.Totally 4,395 milk samples were used to assesse the apparent(test)prevalence and incidence of bTB using the milk antibody ELISA.The association between levels of bTB milk antibody and milk quality was also evaluated.Milk and serum antibody tests showed a good correlation with a 87.5%(95%CI:61.7%,98.4)positive agreement and 98.7%(95%CI:95.4,99.8)negative agreement.The animal level lactoprevalence ranged from 0.3%(95%CI:0,1.2)to 33.3%(95%CI:26.6,40.6)in different farms and the incidence rate ranged from 0 head/cow-month(95%CI:0,0.02)to 0.04 head/cow-month(95%CI:0.02,0.07).Twenty percent of sampled farms met the criteria for bTB control in China.The prevalence on large-scale farms was lower(p<0.001)than on small farms.The bTB milk antibody levels had a negative correlation with milk yield and a positive correlation with somatic cell count(SCC),milk protein percentage(MPP)and percentage of total solids(TS).According to this research,milk ELISA could be used as a supplement of blood samples to assist in the surveillance for bTB and for alerting control and eradication of bTB.展开更多
OBJECTIVE To analyze the incidence rate and trend of thyroid cancer in Tianjin over a recent 20-year period. METHODS A method of descriptive epidemiology was used to study the occurrence of thyroid cancer. RESULTS Dur...OBJECTIVE To analyze the incidence rate and trend of thyroid cancer in Tianjin over a recent 20-year period. METHODS A method of descriptive epidemiology was used to study the occurrence of thyroid cancer. RESULTS During 1981-2001, the average incidence rate of thyroid cancer was 1.770 per 100,000 with a male to female incidence ratio of 1: 2.74, the occurrence being higher in females than in males. Thyroid cancer incidence increased gradually with time over the 20 years in both males and females, especially the incidence peaked in females of 35-50 years of age. CONCLUSION The rapid increase in the incidence rate of thyroid cancer, especially in females, suggests that further research on the risk factors and preventive efforts related to high-risk women should be conducted.展开更多
This paper develops an SIBR cholera transmission model with general incidence rate. Necessary and sufficient conditions for local and global asymptotic stability of the equilibria are established by Routh Hurwitz crit...This paper develops an SIBR cholera transmission model with general incidence rate. Necessary and sufficient conditions for local and global asymptotic stability of the equilibria are established by Routh Hurwitz criterium, Lyapunov function, and the second additive composite matrix theorem. What is more, exploiting the DED is cover simulation tool, the parameter values of the model are estimated with the 1998-2021 cholera case data in China. Finally, we perform sensitivity analysis for the basic reproduction number to seek for effective interventions for cholera control. .展开更多
In the spread of infectious diseases,intervention levels play a crucial role in shaping interactions between healthy and infected individuals,leading to a nonlinear transmission process.Additionally,the availability o...In the spread of infectious diseases,intervention levels play a crucial role in shaping interactions between healthy and infected individuals,leading to a nonlinear transmission process.Additionally,the availability of medical resources limits the recovery rate of infected patients,adding further nonlinear dynamics to the healing process.Our research introduces novelty by combining nonlinear incidence and recovery rates alongside waning immunity in an epidemic model.We present a modified SIRW-type model,examining the epidemic problem with these factors.Through analysis,we explore conditions for non-endemic and co-existing cases based on the basic reproduction ratio.The local stability of equilibria is verified using the Routh-Hurwitz criteria,while global stability is assessed using Lyapunov functions for each equilibrium.Furthermore,we investigate bifurcations around both non-endemic and co-existing equilibria.Numerically,we give some simulations to support our analytical findings.展开更多
In this paper, we treat the spread of COVID-19 using a delayed stochastic SVIRS (Susceptible, Infected, Recovered, Susceptible) epidemic model with a general incidence rate and differential susceptibility. We start wi...In this paper, we treat the spread of COVID-19 using a delayed stochastic SVIRS (Susceptible, Infected, Recovered, Susceptible) epidemic model with a general incidence rate and differential susceptibility. We start with a deterministic model, then add random perturbations on the contact rate using white noise to obtain a stochastic model. We first show that the delayed stochastic differential equation that describes the model has a unique global positive solution for any positive initial value. Under the condition R<sub>0</sub> ≤ 1, we prove the almost sure asymptotic stability of the disease-free equilibrium of the model.展开更多
Objective:To identify the incidence rate,relative risk,hotspot regions and incidence trend of COVID-19 in Qom province,northwest part of Iran in the first stage of the pandemic.Methods:The study included 1125 official...Objective:To identify the incidence rate,relative risk,hotspot regions and incidence trend of COVID-19 in Qom province,northwest part of Iran in the first stage of the pandemic.Methods:The study included 1125 officially reported PCR-confirmed cases of COVID-19 from 20 February 2020 to 20 April 2020 in 90 regions in Qom city,Iran.The Bayesian hierarchical spatial model was used to model the relative risk of COVID-19 in Qom city,and the segmented regression model was used to estimate the trend of COVID-19 incidence rate.The Poisson distribution was applied for the observed number of COVID-19,and independent Gamma prior was used for inference on log-relative risk parameters of the model.Results:The total incidence rate of COVID-19 was estimated at 89.5 per 100000 persons in Qom city(95%CI:84.3,95.1).According to the results of the Bayesian hierarchical spatial model and posterior probabilities,43.33%of the regions in Qom city have relative risk greater than 1;however,only 11.11%of them were significantly greater than 1.Based on Geographic Information Systems(GIS)spatial analysis,10 spatial clusters were detected as active and emerging hotspot areas in the south and central parts of the city.The downward trend was estimated 10 days after the reporting of the first case(February 7,2020);however,the incidence rate was decreased by an average of 4.24%per day(95%CI:−10.7,−3.5).Conclusions:Spatial clusters with high incidence rates of COVID-19 in Qom city were in the south and central regions due to the high population density.The GIS could depict the spatial hotspot clusters of COVID-19 for timely surveillance and decision-making as a way to contain the disease.展开更多
Globally, hypertension is one of the leading causes of death. It can potentially lead to heart disease and stroke, among others, that could result to premature death. In Ghana, hypertension is considered as a disease ...Globally, hypertension is one of the leading causes of death. It can potentially lead to heart disease and stroke, among others, that could result to premature death. In Ghana, hypertension is considered as a disease that contributes to an increase in outpatients’ attendance. To assess the trend differentials of hypertension-induced deaths in Ghana, Chi-square test for equal proportions and Marascuilo procedure for pairwise comparison were performed using surveillance data on reported number of deaths from 2012 to 2016 across the then ten regions. The results show that incidence of hypertension-induced mortality was significantly different for almost all the regions and over the years. The incidence of hypertension-induced mortality has significantly reduced from 2012 to 2016. However, Volta Region recorded the highest incidence of mortality cases (<em>p</em>-value less of 0.0001) than the other regions during the period under review, while the Upper East Region recorded continuous increase in incidence of mortality cases with the highest in 2016. The Eastern Region, Central Region, and Greater Accra Region recorded significantly (<em>p</em>-value less of 0.0001) higher incidence of hypertension-induced mortality than the Ashanti Region, Brong Ahafo Region, Northern Region, Western Region and Upper West Region. The Upper West Region and Western Region had the lowest incidence of mortality. The decline in trend of hypertension-induced mortality could be attributed to some healthcare interventions put in place during the period. One of these interventions was the introduction of health insurance in 2003, a development which has been shown to affect the health seeking behaviors of the people. It is, therefore, important to investigate factors affecting these spatial and temporal dynamics in order to determine appropriate ways to actively control the hypertension-induced deaths in the country. Public education on health should be intensified so as to totally curb hypertension and its attendant risks.展开更多
It is widely known that cancer is a disease of “old-age”. However available data show that this is not the case for many types of cancers. Incidences of breast and ovarian cancers have varying rates of change with a...It is widely known that cancer is a disease of “old-age”. However available data show that this is not the case for many types of cancers. Incidences of breast and ovarian cancers have varying rates of change with age. Breast cancer data of Arabian-gulf women, show that the incidence rates increase with age and reach a maximum at 39 year. It then declines linearly with age to about 55 years. The rate of increase and its changes with age are similar to those of many other countries. In the premenopausal phase the relationship between incidence and age could be adequately modeled using a linear model for the logarithmic transformations of age and incidence. Similar observations are made for the ovarian cancer incidences. Results: It is shown that the rate of increase in breast and ovarian cancer incidence with respect to age is increasing in the premenopausal ages. Moreover, the burden of the disease with respect to mortality and “Disability Adjusted Life Years” or DALY, varied considerably among the six gulf countries. Conclusions: We conclude, based on the age incidence relationship that the number of cancer cases may double in the next period that follows our study period (1998-2009). Moreover, if the six countries have identical relationship between age and the two types of cancer, there should be an integrated and unified effort to have a common strategy for prevention and control.展开更多
Objective: To predict the daily incidence and fatality rates based on long short-term memory(LSTM) in 4 age groups of COVID-19 patients in Mazandaran Province, Iran.Methods: To predict the daily incidence and fatality...Objective: To predict the daily incidence and fatality rates based on long short-term memory(LSTM) in 4 age groups of COVID-19 patients in Mazandaran Province, Iran.Methods: To predict the daily incidence and fatality rates by age groups, this epidemiological study was conducted based on the LSTM model. All data of COVID-19 disease were collected daily for training the LSTM model from February 22, 2020 to April 10, 2021 in the Mazandaran University of Medical Sciences. We defined 4 age groups, i.e., patients under 29, between 30 and 49, between 50 and 59, and over 60 years old. Then, LSTM models were applied to predict the trend of daily incidence and fatality rates from 14 to 40 days in different age groups. The results of different methods were compared with each other.Results: This study evaluated 5 0826 patients and 5 109 deaths with COVID-19 daily in 20 cities of Mazandaran Province. Among the patients, 25 240 were females(49.7%), and 25 586 were males(50.3%). The predicted daily incidence rates on April 11, 2021 were 91.76, 155.84, 150.03, and 325.99 per 100 000 people, respectively;for the fourteenth day April 24, 2021, the predicted daily incidence rates were 35.91, 92.90, 83.74, and 225.68 in each group per 100 000 people. Furthermore, the predicted average daily incidence rates in 40 days for the 4 age groups were 34.25, 95.68, 76.43, and 210.80 per 100 000 people, and the daily fatality rates were 8.38, 4.18, 3.40, 22.53 per 100 000 people according to the established LSTM model. The findings demonstrated the daily incidence and fatality rates of 417.16 and 38.49 per 100 000 people for all age groups over the next 40 days. Conclusions: The results highlighted the proper performance of the LSTM model for predicting the daily incidence and fatality rates. It can clarify the path of spread or decline of the COVID-19 outbreak and the priority of vaccination in age groups.展开更多
基金Pre-Positioning Programme,Grant/Award Number:H1X/01/a0/OX9Agency for Science,Technology and Research(A*STAR)。
文摘Background:Little is known about stage 1 and 2 pressure injuries that are health care-acquired.We report incidence rates of health care-acquired stage 1 and stage 2 pressure injuries,and,estimate the excess length of stay using four competing analytic methods.We discuss the merits of the different approaches.Methods:We calculated monthly incidence rates for stage 1 and 2 health care-acquired pressure injuries occurring in a large Singapore acute care hospital.To estimate excess stay,we conducted unadjusted comparisons with a control cohort,performed linear regression and then generalized linear regression with a gamma distribution.Finally,we fitted a simple state-based model.The design for the cost attribution work was a retrospective matched cohort study.Results:Incidence rates in 2016 were 0.553%(95%confidence interval[CI]0.55,0.557)and 0.469%(95%CI 0.466,0.472)in 2017.For data censored at 60 days’maximum stay,the unadjusted comparisons showed the highest excess stay at 17.68(16.43-18.93)days and multi-state models showed the lowest at 1.22(0.19,2.23)days.Conclusions:Poor-quality methods for attribution of excess length of stay to pressure injury generate inflated estimates that could mislead decision makers.The findings from the multi-state model,which is an appropriate method,are plausible and illustrate the likely bed-days saved from lowering the risk of these events.Stage 1 and 2 pressure injuries are common and increase costs by prolonging the length of stay.There will be economic value investing in prevention.Using biased estimates of excess length of stay will overstate the potential value of prevention.
基金supported in part by JSPS Fellows,No.237213 of Japan Society for the Promotion of Science to the first authorthe Grant MTM2010-18318 of the MICINN,Spanish Ministry of Science and Innovation to the second authorScientific Research (c),No.21540230 of Japan Society for the Promotion of Science to the third author
文摘In this article, we establish the global asymptotic stability of a disease-free equilibrium and an endemic equilibrium of an SIRS epidemic model with a class of nonlin- ear incidence rates and distributed delays. By using strict monotonicity of the incidence function and constructing a Lyapunov functional, we obtain sufficient conditions under which the endemic equilibrium is globally asymptotically stable. When the nonlinear inci- dence rate is a saturated incidence rate, our result provides a new global stability condition for a small rate of immunity loss.
基金Supported by the National Natural Science Foundation of China(11101323)Supported by the Natural Science Basic Research Plan in Shaanxi Province of China(2014JQ1038)Supported by the Xi’an Polytechnic University Innovation Fund for Graduate Students(CX201608)
文摘In this paper,an SEIR model with nonlinear incidence rates are studied.The basic reproduction number R_0 characterizes the disease transmission dynamics: if R_0≤ 1,the disease-free equilibrium is globally asymptotically stable and the disease always dies out,if R_0> 1 then there is a unique endemic equilibrium which is globally asymptotically stable and the disease persists.
文摘Background: This study aimed to identify the role of human development index (HDI) in the incidence and mortality rates of breast cancer (BC) worldwide. Methods: Data on the age-standardized incidence and mortality rates of BC for 184 countries were obtained from the GLOBOCAN. Data about the HDI and other indices were obtained from the World Bank Report 2013. Linear regression model was used for assessment the effect of HDI on BC occurrence rates. Results: In 2012, BCs were estimated to have affected a total of 1,671,149 individuals (crude rate: 47.8 per 100,000 individuals), and caused 521,907 deaths worldwide (crude rate: 14.7 per 100,000 individuals). Nearly half of total female BC cases (46.3%) with the highest risk of incidence (age-standardized Rate (ASR): 128 per 100,000) had occurred in very high HDI regions. The most proportion of the mortality burden was in low HDI and medium HDI areas. Linear regression analyses showed a direct significant correlation between the incidence of BC and HDI at the global level (B = 104.5, P < 0.001). The mortality rate of BC was not significantly associated with HDI (B = 3.26, P = 0.160). Conclusion: Our study showed that the burden of female BC is enormous in very high HDI and low HID regions. Targeted interventions have the ability to reduce this number significantly through resource-dependent interventions. Moreover, further reductions in mortality could be brought about by increasing access to curative treatment for patients with BC.
文摘Objective: To explore the trends of incidence and mortality rates of stroke in Hanzhong rural population. Methods: Acting as the WHO MONICA project. Results: The incidence rate of stroke was 152.9/100 000. There was decline trend in male(P<0.05). The mortality rate of stroke was 115.9/100 000. There was no significant decline trend during 18-year period (P<0.05). The incidence and mortality rates of stroke of male were higher than those of female(P<0.05).The incidence and mortality rates were all increased with age(P<0.01). Conclusion: It must stick to the long- term prevention measures to decrease incidence rate, and improve the condition of medical treatment to reduce the mortality rate in rural population.
文摘Introduction: Total knee arthroplasty (TKA) has been established as a transformative solution in the treatment of advanced degenerative diseases of the knee, such as osteoarthritis, rheumatoid arthritis, and posttraumatic arthritis. In this sense, TKA surgery, which seeks to replace the damaged joint with prosthetic components, has proven to be highly effective in relieving pain, improving joint function, and, ultimately, significantly increasing patients’ quality of life. The present study describes the TKA and revision knee arthroplasty (RKA) rates and, identifies the associated co morbidities in the Colombian context. Methods: A retrospective cohort study was carried out. It describes demographic and clinical characteristics between two groups of patients, TKA or RKA, and its association with mortality at 30 days, 90 days, or one year after the intervention. Results: The incidence rate of the population undergoing TKA was approximately 11.71 cases per 100,000 inhabitants. Furthermore, the incidence rate for revision knee arthroplasty (RKA) procedures in the same period was around 0.96 per 100,000 inhabitants. In both groups at 30 days postoperatively, a total mortality rate of 0.09%was recorded. When the follow-up was extended to 90 days, it increased to 0.15%;at one year postoperatively, it rose to 0.88%. Conclusion: Mortality after surgery was low in Colombia in 2019. Although RKA is a beneficial procedure, in certain circumstances, it was noted that it carries a higher risk compared to primary TKA. Our results emphasize the importance of careful evaluation of co morbidities and risk factors in patients undergoing these surgical procedures. The application of quality-of-life questionnaires should be considered in future studies on effectiveness and mortality for TKA and RKA in our country.
文摘Objective Acute aortic dissection (AAD) is a catastrophic event with high early mortality rate, but to date, no data on the incidence of AAD in China's Mainland is available. This study aimed to estimate the incidence of AAD in China and characterize the clinical profile, management and in-hospital outcomes of this vascular event. Methods We used the China Health Insurance Research Data (the CHIRA Data) 2011 which comprises all inpatient hospital records (300,886) during the period of Jan. 1st 2011 to Dec. 31 2011 of 3,335,000 randomly sampled beneficiaries (1,718,500 men and 1,616,500 women) from 25 cities and counties in different economic-geographic regions of China's Mainland. Patients with acute aortic dissection were identified according to International Classification of Disease 10m Revision (ICD-10) of I71.0, The estimated incidence of AAD was calculated using the equation: estimated incidence = 2.0 × (40% × hospital admission rate) + 60% × hospital admission rate. Results The hospital admission rate was 2.0/100,000 (65/3,325,000, 95% CI: 1.2-2.8). The estimated annual incidence of AAD was 2.8/100,000 (95% CI: 1.9-3.6) and was higher in male than in female (3.7 vs. 1.5, P 〈 0.001). The mean age was 58.9 ± 13.4 years. During the mean hospital stay of 23 ±6 days, the overall in-hospital mortality was 13.9% (9/65). Conclusions Our study showed relatively lower but not negligible incidence and in-hospital mortality of AAD in the mainland of China. The mean age of patients with AAD in Chinese was younger than that reported by researches from west countries, while the male to female incidence ratio is similar to those reported by other studies.
文摘This paper considers two differential infectivity(DI) epidemic models with a nonlinear incidence rate and constant or varying population size. The models exhibits two equilibria, namely., a disease-free equilibrium O and a unique endemic equilibrium. If the basic reproductive number σ is below unity,O is globally stable and the disease always dies out. If σ〉1, O is unstable and the sufficient conditions for global stability of endemic equilibrium are derived. Moreover,when σ〈 1 ,the local or global asymptotical stability of endemic equilibrium for DI model with constant population size in n-dimensional or two-dimensional space is obtained.
文摘A SIQS epidemic model with saturated incidence rate is studied. Two equilibrium points exist for the system, disease-free and endemic equilibrium. The stability of the disease-free equilibrium and endemic equilibrium exists when the basic reproduction number R0, is less or greater than unity respectively. The global stability of the disease-free and endemic equilibrium is proved using Lyapunov functions and Poincare-Bendixson theorem plus Dulac’s criterion respectively.
文摘In a polluted environment, considering the biological population infected with a kind of disease and hunted by human beings, we formulate a nonautonomous SIR population-epidemic model with time-varying impulsive release and general nonlinear incidence rate and investigate dynamical behaviors of the model. Under the reasonable assumptions, the sufficient conditions which guarantee the globally attractive of the disease-free periodic solution and the permanence of the infected fish are established, that is, the infected fish dies out if , whereas the disease persists if . To substantiate our theoretical results, extensive numerical simulations are performed for a hypothetical set of parameter values.
基金supported by Research Fund from Department of Health of Hubei Province for Hepatitis B Epidemiology and Immunization Protection Strategy Study(No.JX5B29)
文摘This study examined the change of reported incidence rate for viral hepatitis in Hubei province, China, between 2004 to 2010 to provide scientific evidence for viral hepatitis control. Reported viral hepatitis infection cases were queried from Centre for Disease Control of Hubei Province, China. The incidence of viral hepatitis A decreased steadily across the study period. Viral hepatitis B composed 85% of the viral hepatitis cases. When reported incidence rates for chronic hepatitis B increased, the rates of acute and unclassified cases dropped from 2005 to 2010. The reported viral hepatitis B incidence rate for males was around 1.5-2 times higher than for females. The average annual percentage change of reported viral hepatitis B incidence rates was 4%. The same index for viral hepatitis C was 28%. The reported viral hepatitis B incidence rate of people under 20 years old declined over the period. This decrease was mainly attributed to the recent implementation of vaccination plan. Reported incidence rate of viral hepatitis E also rose in those years. Having a better understanding on reported incidence rates of the present surveillance system is important for developing strategies for further prevention of viral hepatitis. In addition, the data showed that a surveillance system that differentiates new and former infected cases will be more effective in providing evidence for disease control.
基金the Natural Science Foundation of China(U21A20259)National Key Research and Development Program of Ningxia Hui Autonomous Region(2021BEF02028)+1 种基金the Natural Science Foundation of Hubei Province(2021CFA016)China Agriculture Research System of MOF and MARA and Basic and technical innovation team for prevention and control of bovine disease.
文摘Bovine tuberculosis(bTB)is a chronic zoonotic disease that is endemic in China.Current in-vitro tests for bTB are mainly based on blood assays.Collection of samples results in some stress to the sampled cattle and associated economic losses for the herd owner.This study was designed to investigate the relationship between milk and serum antibody tests for bTB in dairy cows using 85 cows with milk and corresponding blood samples.Totally 4,395 milk samples were used to assesse the apparent(test)prevalence and incidence of bTB using the milk antibody ELISA.The association between levels of bTB milk antibody and milk quality was also evaluated.Milk and serum antibody tests showed a good correlation with a 87.5%(95%CI:61.7%,98.4)positive agreement and 98.7%(95%CI:95.4,99.8)negative agreement.The animal level lactoprevalence ranged from 0.3%(95%CI:0,1.2)to 33.3%(95%CI:26.6,40.6)in different farms and the incidence rate ranged from 0 head/cow-month(95%CI:0,0.02)to 0.04 head/cow-month(95%CI:0.02,0.07).Twenty percent of sampled farms met the criteria for bTB control in China.The prevalence on large-scale farms was lower(p<0.001)than on small farms.The bTB milk antibody levels had a negative correlation with milk yield and a positive correlation with somatic cell count(SCC),milk protein percentage(MPP)and percentage of total solids(TS).According to this research,milk ELISA could be used as a supplement of blood samples to assist in the surveillance for bTB and for alerting control and eradication of bTB.
文摘OBJECTIVE To analyze the incidence rate and trend of thyroid cancer in Tianjin over a recent 20-year period. METHODS A method of descriptive epidemiology was used to study the occurrence of thyroid cancer. RESULTS During 1981-2001, the average incidence rate of thyroid cancer was 1.770 per 100,000 with a male to female incidence ratio of 1: 2.74, the occurrence being higher in females than in males. Thyroid cancer incidence increased gradually with time over the 20 years in both males and females, especially the incidence peaked in females of 35-50 years of age. CONCLUSION The rapid increase in the incidence rate of thyroid cancer, especially in females, suggests that further research on the risk factors and preventive efforts related to high-risk women should be conducted.
文摘This paper develops an SIBR cholera transmission model with general incidence rate. Necessary and sufficient conditions for local and global asymptotic stability of the equilibria are established by Routh Hurwitz criterium, Lyapunov function, and the second additive composite matrix theorem. What is more, exploiting the DED is cover simulation tool, the parameter values of the model are estimated with the 1998-2021 cholera case data in China. Finally, we perform sensitivity analysis for the basic reproduction number to seek for effective interventions for cholera control. .
基金funded by Universitas Padjadjaran,Indonesia,via Hibah Riset Data Pustaka dan Daring Universitas Padjadjaran,No.1549/UN6.3.1/PT.00/2023.
文摘In the spread of infectious diseases,intervention levels play a crucial role in shaping interactions between healthy and infected individuals,leading to a nonlinear transmission process.Additionally,the availability of medical resources limits the recovery rate of infected patients,adding further nonlinear dynamics to the healing process.Our research introduces novelty by combining nonlinear incidence and recovery rates alongside waning immunity in an epidemic model.We present a modified SIRW-type model,examining the epidemic problem with these factors.Through analysis,we explore conditions for non-endemic and co-existing cases based on the basic reproduction ratio.The local stability of equilibria is verified using the Routh-Hurwitz criteria,while global stability is assessed using Lyapunov functions for each equilibrium.Furthermore,we investigate bifurcations around both non-endemic and co-existing equilibria.Numerically,we give some simulations to support our analytical findings.
文摘In this paper, we treat the spread of COVID-19 using a delayed stochastic SVIRS (Susceptible, Infected, Recovered, Susceptible) epidemic model with a general incidence rate and differential susceptibility. We start with a deterministic model, then add random perturbations on the contact rate using white noise to obtain a stochastic model. We first show that the delayed stochastic differential equation that describes the model has a unique global positive solution for any positive initial value. Under the condition R<sub>0</sub> ≤ 1, we prove the almost sure asymptotic stability of the disease-free equilibrium of the model.
文摘Objective:To identify the incidence rate,relative risk,hotspot regions and incidence trend of COVID-19 in Qom province,northwest part of Iran in the first stage of the pandemic.Methods:The study included 1125 officially reported PCR-confirmed cases of COVID-19 from 20 February 2020 to 20 April 2020 in 90 regions in Qom city,Iran.The Bayesian hierarchical spatial model was used to model the relative risk of COVID-19 in Qom city,and the segmented regression model was used to estimate the trend of COVID-19 incidence rate.The Poisson distribution was applied for the observed number of COVID-19,and independent Gamma prior was used for inference on log-relative risk parameters of the model.Results:The total incidence rate of COVID-19 was estimated at 89.5 per 100000 persons in Qom city(95%CI:84.3,95.1).According to the results of the Bayesian hierarchical spatial model and posterior probabilities,43.33%of the regions in Qom city have relative risk greater than 1;however,only 11.11%of them were significantly greater than 1.Based on Geographic Information Systems(GIS)spatial analysis,10 spatial clusters were detected as active and emerging hotspot areas in the south and central parts of the city.The downward trend was estimated 10 days after the reporting of the first case(February 7,2020);however,the incidence rate was decreased by an average of 4.24%per day(95%CI:−10.7,−3.5).Conclusions:Spatial clusters with high incidence rates of COVID-19 in Qom city were in the south and central regions due to the high population density.The GIS could depict the spatial hotspot clusters of COVID-19 for timely surveillance and decision-making as a way to contain the disease.
文摘Globally, hypertension is one of the leading causes of death. It can potentially lead to heart disease and stroke, among others, that could result to premature death. In Ghana, hypertension is considered as a disease that contributes to an increase in outpatients’ attendance. To assess the trend differentials of hypertension-induced deaths in Ghana, Chi-square test for equal proportions and Marascuilo procedure for pairwise comparison were performed using surveillance data on reported number of deaths from 2012 to 2016 across the then ten regions. The results show that incidence of hypertension-induced mortality was significantly different for almost all the regions and over the years. The incidence of hypertension-induced mortality has significantly reduced from 2012 to 2016. However, Volta Region recorded the highest incidence of mortality cases (<em>p</em>-value less of 0.0001) than the other regions during the period under review, while the Upper East Region recorded continuous increase in incidence of mortality cases with the highest in 2016. The Eastern Region, Central Region, and Greater Accra Region recorded significantly (<em>p</em>-value less of 0.0001) higher incidence of hypertension-induced mortality than the Ashanti Region, Brong Ahafo Region, Northern Region, Western Region and Upper West Region. The Upper West Region and Western Region had the lowest incidence of mortality. The decline in trend of hypertension-induced mortality could be attributed to some healthcare interventions put in place during the period. One of these interventions was the introduction of health insurance in 2003, a development which has been shown to affect the health seeking behaviors of the people. It is, therefore, important to investigate factors affecting these spatial and temporal dynamics in order to determine appropriate ways to actively control the hypertension-induced deaths in the country. Public education on health should be intensified so as to totally curb hypertension and its attendant risks.
文摘It is widely known that cancer is a disease of “old-age”. However available data show that this is not the case for many types of cancers. Incidences of breast and ovarian cancers have varying rates of change with age. Breast cancer data of Arabian-gulf women, show that the incidence rates increase with age and reach a maximum at 39 year. It then declines linearly with age to about 55 years. The rate of increase and its changes with age are similar to those of many other countries. In the premenopausal phase the relationship between incidence and age could be adequately modeled using a linear model for the logarithmic transformations of age and incidence. Similar observations are made for the ovarian cancer incidences. Results: It is shown that the rate of increase in breast and ovarian cancer incidence with respect to age is increasing in the premenopausal ages. Moreover, the burden of the disease with respect to mortality and “Disability Adjusted Life Years” or DALY, varied considerably among the six gulf countries. Conclusions: We conclude, based on the age incidence relationship that the number of cancer cases may double in the next period that follows our study period (1998-2009). Moreover, if the six countries have identical relationship between age and the two types of cancer, there should be an integrated and unified effort to have a common strategy for prevention and control.
文摘Objective: To predict the daily incidence and fatality rates based on long short-term memory(LSTM) in 4 age groups of COVID-19 patients in Mazandaran Province, Iran.Methods: To predict the daily incidence and fatality rates by age groups, this epidemiological study was conducted based on the LSTM model. All data of COVID-19 disease were collected daily for training the LSTM model from February 22, 2020 to April 10, 2021 in the Mazandaran University of Medical Sciences. We defined 4 age groups, i.e., patients under 29, between 30 and 49, between 50 and 59, and over 60 years old. Then, LSTM models were applied to predict the trend of daily incidence and fatality rates from 14 to 40 days in different age groups. The results of different methods were compared with each other.Results: This study evaluated 5 0826 patients and 5 109 deaths with COVID-19 daily in 20 cities of Mazandaran Province. Among the patients, 25 240 were females(49.7%), and 25 586 were males(50.3%). The predicted daily incidence rates on April 11, 2021 were 91.76, 155.84, 150.03, and 325.99 per 100 000 people, respectively;for the fourteenth day April 24, 2021, the predicted daily incidence rates were 35.91, 92.90, 83.74, and 225.68 in each group per 100 000 people. Furthermore, the predicted average daily incidence rates in 40 days for the 4 age groups were 34.25, 95.68, 76.43, and 210.80 per 100 000 people, and the daily fatality rates were 8.38, 4.18, 3.40, 22.53 per 100 000 people according to the established LSTM model. The findings demonstrated the daily incidence and fatality rates of 417.16 and 38.49 per 100 000 people for all age groups over the next 40 days. Conclusions: The results highlighted the proper performance of the LSTM model for predicting the daily incidence and fatality rates. It can clarify the path of spread or decline of the COVID-19 outbreak and the priority of vaccination in age groups.