Trend of Lassa fever cases and factors associated with mortality in Liberia, 2016 - 2021: a secondary data analysis.

Introduction: Lassa fever (LF) is endemic in Liberia and is immediately reportable. Suspected cases are confirmed at the National Public Health Reference Laboratory. However, there is limited information on the trend and factors associated with mortality. We described the epidemiological characteristics of LF cases and determined factors associated with mortality in Liberia from 2016 to 2021. Methods: we reviewed 867 case-based LF surveillance data from 2016 to 2021 obtained from the National Public Health Institute of Liberia (NPHIL). The cases that met the suspected LF case definition were tested with RT-PCR. Using Epi Info 7.2.5.0. We conducted univariate, bivariate, and multivariate and analysis. We calculated frequencies, proportions. Positivity rate, case fatality rate, and factors associated with LF mortality using chi-square statistics and logistics regression at 5% level of significance. Results: eighty-five percent (737/867) of the suspected cases were tested and 26.0% (192/737) were confirmed LF positive. The median age of confirmed LF cases was 21(IQR: 12-34) years. Age 10-19 years accounted for 24.5% (47/192) and females 54.2% (104/192). Bong 33.9% (65/192), Grand Bassa 31.8% (61/192), and Nimba counties, 21.9% (42/192) accounted for most of the cases. The median duration from symptom onset to hospital admission was 6 (IQR: 3-9) days. A majority, 66% (126/192) of the cases were reported during the dry season (October-March) and annual incidence was highest at 12 cases per 1,000,000 population in 2019 and 2020. The overall case fatality rate was 44.8%. Non-endemic counties, Margibi, 77.8% and Montserrado, 66.7% accounted for the highest case fatality rate (CFR), while 2018, 66.7% and 2021, 60.0% recorded the highest CFR during the period. Age ≥30 years (aOR=2.1,95% CI: 1.08-4.11, p=0.027) and residing in Grand Bassa County (aOR=0.3, 95% CI: 0.13-0.73, p=0.007) were associated with LF mortality. Conclusion: Lassa fever was endemic in three of the fifteen counties of Liberia, case fatality rate remained generally high and widely varied. The high fatality of LF has been reported to the NPHIL and is currently being further investigated. There is a need to continuously train healthcare workers, especially in non-endemic counties to improve the LF treatment outcome.

Effect of vaccination patterns and vaccination rates on the spread and mortality of the COVID-19 pandemic.

Objectives: Acquiring herd immunity through vaccination is the best way to curb the COVID-19 infection. Many countries have attempted to reach the herd immunity threshold as early as possible since the commencement of vaccination at the end of 2020. The purpose of this study is to (1) examine whether the pattern of vaccination rates affects the spread of COVID-19 and the consequent mortality and (2) investigate the level of cumulative vaccination rates that can begin to have an impact on reducing the spread and mortality of the pandemic. Methods: This study selected 33 countries with higher vaccination rates as its sample set, classifying them into three groups as per vaccination patterns. Results: The results showed that vaccination patterns have a significant impact on reducing spread and mortality. The full-speed vaccination pattern showed greater improvement in the spread of the COVID-19 pandemic than the other two patterns, while the striving vaccination pattern improved the most in terms of mortality. Secondly, the spread and mortality of the COVID pandemic started to significantly decline when the average cumulative vaccination rate reached 29.06 doses per 100 people and 7.88 doses per 100 people, respectively. Conclusion: The study highlights the important role of vaccination patterns and the VTMR in reducing the epidemic spread and mortality.

Effect of mutation and vaccination on spread, severity, and mortality of COVID-19 disease.

Coronavirus disease 2019 (COVID-19) has had different waves within the same country. The spread rate and severity showed different properties within the COVID-19 different waves. The present work aims to compare the spread and the severity of the different waves using the available data of confirmed COVID-19 cases and death cases. Real-data sets collected from the Johns Hopkins University Center for Systems Science were used to perform a comparative study between COVID-19 different waves in 12 countries with the highest total performed tests for severe acute respiratory syndrome coronavirus 2 detection in the world (Italy, Brazil, Japan, Germany, Spain, India, USA, UAE, Poland, Colombia, Turkey, and Switzerland). The total number of confirmed cases and death cases in different waves of COVID-19 were compared to that of the previous one for equivalent periods. The total number of death cases in each wave was presented as a percentage of the total number of confirmed cases for the same periods. In all the selected 12 countries, Wave 2 had a much higher number of confirmed cases than that in Wave 1. However, the death cases increase was not comparable with that of the confirmed cases to the extent that some countries had lower death cases than in Wave 1, UAE, and Spain. The death cases as a percentage of the total number of confirmed cases in Wave 1 were much higher than that in Wave 2. Some countries have had Waves 3 and 4. Waves 3 and 4 have had lower confirmed cases than Wave 2, however, the death cases were variable in different countries. The death cases in Waves 3 and 4 were similar to or higher than Wave 2 in most countries. Wave 2 of COVID-19 had a much higher spread rate but much lower severity resulting in a lower death rate in Wave 2 compared with that of the first wave. Waves 3 and 4 have had lower confirmed cases than Wave 2; that could be due to the presence of appropriate treatment and vaccination. However, that was not reflected in the death cases, which were similar to or higher than Wave 2 in most countries. Further studies are needed to explain these findings.

Modeling the Number of Confirmed Cases and Deaths from the COVID-19 Pandemic in the UK and Forecasting from April 15 to May 30, 2020.

OBJECTIVE: The UK is one of the epicenters of coronavirus disease (COVID-19) in the world. As of April 14, there have been 93 873 confirmed patients of COVID-19 in the UK and 12 107 deaths with confirmed infection. On April 14, it was reported that COVID-19 was the cause of more than half of the deaths in London. METHODS: The present paper addresses the modeling and forecasting of the outbreak of COVID-19 in the UK. This modeling must be accomplished through a 2-part time series model to study the number of confirmed cases and deaths. The period we aimed at a forecast was 46 days from April 15 to May 30, 2020. All the computations and simulations were conducted on Matlab R2015b, and the average curves and confidence intervals were calculated based on 100 simulations of the fitted models. RESULTS: According to the obtained model, we expect that the cumulative number of confirmed cases will reach 282 000 with an 80% confidence interval (242 000 to 316 500) on May 30, from 93 873 on April 14. In addition, it is expected that, over this period, the number of daily new confirmed cases will fall to the interval 1330 to 6450 with the probability of 0.80 by the point estimation around 3100. Regarding death, our model establishes that the real case fatality rate of the pandemic in the UK approaches 11% (80% confidence interval: 8%-15%). Accordingly, we forecast that the total death in the UK will rise to 35 000 (28 000-50 000 with the probability of 80%). CONCLUSIONS: The drawback of this study is the shortage of observations. Also, to conduct a more exact study, it is possible to take the number of the tests into account as an explanatory variable besides time.

Effect of Socioeconomic and Ethnic Characteristics on COVID-19 Infection: the Case of the Ultra-Orthodox and the Arab Communities in Israel.

BACKGROUND: During infectious disease outbreaks, the weakest communities are more vulnerable to infection and its deleterious effects. In Israel, the Arab and Ultra-Orthodox Jewish communities have unique demographic and cultural characteristics that place them at higher risk of infection. OBJECTIVE: To examine socioeconomic and ethnic differences in rates of COVID-19 testing, confirmed cases and deaths, and to analyze patterns of transmission in ethnically diverse communities. METHODS: A cross-sectional ecologic study design was used. Consecutive data on rates of COVID-19 diagnostic testing, lab-confirmed cases, and deaths collected from March 31 through May 1, 2020, in 174 localities across Israel (84% of the population) were analyzed by socioeconomic ranking and ethnicity. RESULTS: Tests were performed on 331,594 individuals (4.29% of the total population). Of those, 14,865 individuals (4.48%) were positive for COVID-19 and 203 died (1.37% of confirmed cases). Testing rate was 26% higher in the lowest SE category compared with the highest. The risk of testing positive was 2.16 times higher in the lowest socioeconomic category, compared with the highest. The proportion of confirmed cases was 4.96 times higher in the Jewish compared with the Arab population. The rate of confirmed cases in 2 Ultra-Orthodox localities increased relatively early and quickly. Other Jewish and Arab localities showed consistently low rates of confirmed COVID-19 cases, regardless of socioeconomic ranking. CONCLUSIONS: Culturally different communities reacted differently to the COVID-19 outbreak and to government measures, resulting in different outcomes. Socioeconomic and ethnic variables cannot fully explain communities' reaction to the pandemic. Our findings stress the need for a culturally adapted approach for dealing with health crises.

Using Social Network Analysis to Identify Spatiotemporal Spread Patterns of COVID-19 around the World: Online Dashboard Development.

The COVID-19 pandemic has spread widely around the world. Many mathematical models have been proposed to investigate the inflection point (IP) and the spread pattern of COVID-19. However, no researchers have applied social network analysis (SNA) to cluster their characteristics. We aimed to illustrate the use of SNA to identify the spread clusters of COVID-19. Cumulative numbers of infected cases (CNICs) in countries/regions were downloaded from GitHub. The CNIC patterns were extracted from SNA based on CNICs between countries/regions. The item response model (IRT) was applied to create a general predictive model for each country/region. The IP days were obtained from the IRT model. The location parameters in continents, China, and the United States were compared. The results showed that (1) three clusters (255, n = 51, 130, and 74 in patterns from Eastern Asia and Europe to America) were separated using SNA, (2) China had a shorter mean IP and smaller mean location parameter than other counterparts, and (3) an online dashboard was used to display the clusters along with IP days for each country/region. Spatiotemporal spread patterns can be clustered using SNA and correlation coefficients (CCs). A dashboard with spread clusters and IP days is recommended to epidemiologists and researchers and is not limited to the COVID-19 pandemic.

COVID-19 caseness: An epidemiologic perspective.

The concept of caseness in the COVID-19 virus is important for early case finding and reporting. These are essential steps for prevention and control. This review defines and differentiates between types of cases and specifies the elements of each case definition in general with their application to COVID-19, where appropriate. These terms and their application are useful for the surveillance team, epidemiologists, clinicians, policy makers as well as the public in general.

Epidemiological characteristics of 123 confirmed COVID-19 cases in Shangrao City， Jiangxi / 上海预防医学

ObjectiveTo describe the epidemiological characteristics of confirmed COVID-19 cases in Shangrao City， and provide scientific evidence for the development of prevention and control strategies. MethodsEpidemiological characteristics of 123 confirmed cases， such as time， sex， age， occupations， area， and source of infection， were analyzed by combining epidemiological investigation with laboratory testing. ResultsOf the 123 confirmed cases， 34 were imported cases and 89 were local cases. The sex ratio was 1.32∶1. Average time interval of the COVID-19 was （18.4±4.4） days， with a median time interval between the onset and final diagnosis of 5 days. There were 19 clustering cases， of which 89.5% were family clusters and 77.3% occurred in families. Majority of the cases were common type. The main source of infection was travelers from the epidemic areas. ConclusionHealth monitoring of travelers from epidemic areas and strict quarantine of close contacts are the main measures to control the spread of the COVID-19 epidemic.

Epidemiological characteristics of 123 confirmed COVID-19 cases in Shangrao City， Jiangxi / 上海预防医学

ObjectiveTo describe the epidemiological characteristics of confirmed COVID-19 cases in Shangrao City， and provide scientific evidence for the development of prevention and control strategies. MethodsEpidemiological characteristics of 123 confirmed cases， such as time， sex， age， occupations， area， and source of infection， were analyzed by combining epidemiological investigation with laboratory testing. ResultsOf the 123 confirmed cases， 34 were imported cases and 89 were local cases. The sex ratio was 1.32∶1. Average time interval of the COVID-19 was （18.4±4.4） days， with a median time interval between the onset and final diagnosis of 5 days. There were 19 clustering cases， of which 89.5% were family clusters and 77.3% occurred in families. Majority of the cases were common type. The main source of infection was travelers from the epidemic areas. ConclusionHealth monitoring of travelers from epidemic areas and strict quarantine of close contacts are the main measures to control the spread of the COVID-19 epidemic.

A suspected case of COVID-19 turned into a confirmed case: a case report.

COVID-19 (coronavirus disease 2019) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and discovered in 2019. The clinical manifestations include fever, coughing, difficulty in breathing and even death from multiple organ failure. Nucleic acid test is the golden standard method for confirmation of infection. According to the Chinese 'Seventh Edition of the COVID-19 Diagnosis and Treatment Protocol', suspected patients with negative nucleic acid tests from two consecutive airway specimens can be excluded from diagnosis and released from quarantine. The current report describes a suspected COVID-19 case that had a history of close contact with a COVID-19 patient. The diagnosis was confirmed after the SARS-CoV-2 nucleic acid was detected after four sputum sample tests (sampling interval of at least 24 h).

Estimation of global case fatality rate of coronavirus disease 2019 (COVID-19) using meta-analyses: Comparison between calendar date and days since the outbreak of the first confirmed case.

OBJECTIVE: Since the outbreak of the coronavirus disease 2019 (COVID-19) in December of 2019 in China, estimating the pandemic's case fatality rate (CFR) has been the focus and interest of many stakeholders. In this manuscript, we prove that the method of using the cumulative CFR is static and does not reflect the trend according to the daily change per unit of time. METHODS: A proportion meta-analysis was carried out on the CFR in every country reporting COVID-19 cases. Based on these results, we performed a meta-analysis for a global COVID-19 CFR. Each analysis was performed using two different calculations of CFR: according to the calendar date and according to the days since the outbreak of the first confirmed case. We thus explored an innovative and original calculation of CFR, concurrently based on the date of the first confirmed case as well as on a daily basis. RESULTS: For the first time, we showed that using meta-analyses according to the calendar date and days since the outbreak of the first confirmed case, were different. CONCLUSION: We propose that a CFR according to days since the outbreak of the first confirmed case might be a better predictor of the current CFR of COVID-19 and its kinetics.

Epidemiological characteristics of patients with coronavirus disease 2019 in Chenzhou City / 上海预防医学

Objective To identify the epidemiological features of COVID-19 epidemic in Chenzhou City, Hunan province so as to provide scientific evidence for effective containment of the COVID-19 epidemic. Methods Descriptive epidemiological method was used to retrospectively characterize the confirmed COVID-19 cases and asymptomatic cases in Chenzhou City from January 23 through March 10, 2020. Results A total of 39 confirmed COVID-19 cases and 6 asymptomatic cases infection were documented in the city, with no death.We identified 8 clusters of COVID-19, which were all familial transmission.There was statistical difference between the sources of different types of epidemic (χ2=15.996, P < 0.001), in which all the local COVID-19 cases were the secondary cases in the clusters.As the epidemic expanded, the trend shifted from imported-case-centered to local-case-centered.The epidemic has covered 81.81% of the city area; in each area, the first COVID-19 cases were all imported. Conclusion The COVID-19 epidemic has been effectively controlled.At present, we focus on the quarantine in the entry and exit to prevent the imported epidemic.

Associated factors in distinguishing patients with brucellosis from suspected cases.

BACKGROUND: To investigate the risk factors for brucellosis in suspected cases of the disease. METHODS: A self-designed questionnaire was developed to collect data from 3557 people whose initial visit site was the Songyuan Center for Disease Control and Prevention (CDC) from January 1st, 2009 to December 31st, 2012. After collecting blood samples, a plate agglutination test (PAT) and serum agglutination test (SAT) were used to distinguish the patients with brucellosis from the suspected cases. RESULTS: Sex, occupation (farmers and herdsmen), contact with abortion products, and contact with feces were the main risk factors for brucellosis in the suspected cases (all P < 0.05). No difference existed between the confirmed cases and suspected cases in the demographic characteristics, contact with animals (except swine), contact with substances, or clinical symptoms (except fever). However, the confirmed cases showed significant differences from people without brucellosis in demographic characteristics, contact with animals (except cattle and swine), contact with substances, and clinical symptoms. Suspected cases exhibited significant differences from people without brucellosis in the demographic characteristics (except education), contact with animals (except swine), contact with substances (except dust), and clinical symptoms (except chills and acratia). Brucella was cultured from the blood samples of three of 30 suspected cases with fever. Using AMOS-PCR and agarose electrophoresis, the detailed species of Brucella strain was identified as Brucella melitensis. CONCLUSIONS: Abortion products and feces are the main risk factors for brucellosis in suspected cases of the disease. Pyrexia in suspected cases with a history of contact with abortion products or feces should raise suspicion for the disease.

First case of laboratory-confirmed severe fever with thrombocytopenia syndrome disease revealed the risk of SFTSV infection in Xinjiang, China.

The Xinjiang Uygur Autonomous Region locating in Northwest of China was not considered the epidemic area of severe fever with thrombocytopenia syndrome (SFTS). Here we report the first laboratory-confirmed SFTS case that a female patient had tick bite in Xinjiang and illness onset after returning to Hainan Province. Laboratory tests identified SFTS virus (SFTSV) infection, and the virus was isolated from the patient's serum sample. Furthermore, SFTSV prevalence among tick groups was identified, and IgM response to SFTSV from febrile patients was identified. The findings suggested that there have been risks of SFTSV infection due to exposure to ticks in Xinjiang.

[Epidemiological investigation on confirmed cases of schistosomiasis in Hubei Province].

OBJECTIVE: To grasp the distribution and epidemiology of confirmed cases of schistosomiasis in Hubei Province, so as to provide the evidence for promoting the prevention and control work. METHODS: The confirmed cases of schistosomiasis in Hubei Province from 2010 to 2014 were epidemiologically investigated, and the prevalence characteristics and main influencing factors were analyzed. RESULTS: A total of 10 102 confirmed cases from 2010 to 2014 were surveyed. There were 1 062 local infected patients, accounting for 10.51% and including 354 repeated infections and 17 newly infected. There were 290 foreigninfected patients, accounting for 2.87%, with 206 repeated infection cases and 84 newly infected. There were 8 750 historical patients, including 2 229 patients who leaked the former schistosomiasis investigations, accounting for 22.06%; 570 patients missed treatment, accounting for 5.64%; 3 640 patients were treated with non-standard therapy, accounting for 36.03%; 2 311 patients were treated with poor medication efficacy, accounting for 22.88%. The multivariate non-conditional Logistic regression, targeting at confirmed cases in 2014, showed that, for the leaking investigations, the potential risk factors included the age, educational level, and latrine renovation (b＞0, OR＞1), the protective factors were the times of previous treatment, cattle feeding in villager team, and Oncomelania hupensis snails in surroundings (b＜0, OR＜1); for the treatment-missing, the age, educational level, snails in the surroundings of residence were risk factors (b＜0, OR＜1); for the substandard treatment, the risk factors included the occupation and snails in the surroundings of residence (b＞0, OR＞1), and the educational level and snails in the own field were protective factors (b＜0, OR＜1). CONCLUSIONS: The epidemiological investigation on the confirmed cases of schistosomiasis could grasp the epidemic factors so as to improve the management and carry out the scientific control.

Epidemiological investigation on confirmed cases of schistosomiasis in Hu-bei Province / 中国血吸虫病防治杂志

Objective To grasp the distribution and epidemiology of confirmed cases of schistosomiasis in Hubei Province, so as to provide the evidence for promoting the prevention and control work. Methods The confirmed cases of schistosomiasis in Hubei Province from 2010 to 2014 were epidemiologically investigated,and the prevalence characteristics and main influenc?ing factors were analyzed. Results A total of 10 102 confirmed cases from 2010 to 2014 were surveyed. There were 1 062 local infected patients,accounting for 10.51%and including 354 repeated infections and 17 newly infected. There were 290 foreign?infected patients,accounting for 2.87%,with 206 repeated infection cases and 84 newly infected. There were 8 750 historical patients,including 2 229 patients who leaked the former schistosomiasis investigations,accounting for 22.06%;570 patients missed treatment,accounting for 5.64%;3 640 patients were treated with non?standard therapy,accounting for 36.03%;2 311 patients were treated with poor medication efficacy,accounting for 22.88%. The multivariate non?conditional Logistic regres?sion,targeting at confirmed cases in 2014,showed that,for the leaking investigations,the potential risk factors included the age,educational level,and latrine renovation(b>0,OR>1),the protective factors were the times of previous treatment,cat?tle feeding in villager team,and Oncomelania hupensis snails in surroundings(b0,OR>1),and the educational level and snails in the own field were protective factors(b<0,OR<1). Conclusion The epidemiological investigation on the confirmed cases of schistosomiasis could grasp the epidemic factors so as to improve the management and carry out the scientific control.

Características clínicas y sociodemográficas de niños menores de 13 años con diagnóstico confirmado de tuberculosis pulmonar o sin él, en el Hospital Universitario San Vicente de Paúl, Medellín, Colombia, 2007-2008 / Clinical and sociodemographic characteristics of children, younger than13 years, with or without a confirmed diagnosis of pulmonary tuberculosis, at Hospital Universitario San Vicente de Paúl, Medellín, Colombia, 2007-2008

Introducción: la tuberculosis (TB) es una de las enfermedades infectocontagiosas más importantes en el mundo debido a que se asocia con altas tasas de morbilidad y mortalidad. En niños puede afectar cualquier órgano o sistema, a cualquier edad, pero con mayor frecuencia es pulmonar. Tiene graves consecuencias si no se la diagnostica y trata de forma oportuna y adecuada. Los síntomas y signos son variados e inespecíficos lo que, sumado a la dificultad en el aislamiento del Mycobacterium tuberculosis a partir de muestras de niños disminuye la probabilidad de hacer el diagnóstico. Objetivo: puntualizar las características clínicas y sociodemográficas de un grupo de niños con sospecha o diagnóstico final de tuberculosis pulmonar. Metodología: la población en estudio correspondió a 56 niños menores de 13 años atendidos en los servicios pediátricos de urgencias y hospitalización del Hospital Universitario San Vicente de Paúl, en Medellín, a quienes se les sospechó o confirmó TB pulmonar, según los criterios de la OMS, entre julio de 2007 y diciembre de 2008. Se aplicó un formulario para la recolección de los datos, que se obtuvieron directamente de los pacientes o sus acudientes, y se completaron con las historias clínicas en el archivo del hospital. Resultados: en 38 de los 56 niños (67,9%) se confirmó el diagnóstico de tuberculosis pulmonar. El 87,5% pertenecían a los estratos socioeconómicos más bajos (1 y 2); 55% provenían del área urbana de Medellín, 70% eran mestizos y 28,6%, indígenas. La tos y la fiebre fueron las manifestaciones más comunes en el grupo con diagnóstico definitivo de TB; el criterio epidemiológico fue positivo en 53,6% de los casos, el radiológico en 51,8% y el tuberculínico, en 41,1%. Conclusión: la TB pulmonar sigue presente en la población infantil y se debe tener un alto índice de sospecha clínica para detectarla, pues las manifestaciones son variadas e inespecíficas...

Introduction: Worldwide, tuberculosis is one of the most important infectious and contagious diseases. It is associated with high morbidity and mortality rates. In children, tuberculosis is most frequently pulmonary but it may affect every organ and system. Its consequences, if inadequately treated, may be severe. Symptoms and signs are diverse and nonspecific, and the bacteriological confirmation is difficult in children. For these reasons, making the diagnosis in the pediatric population may be a really difficult challenge.Objective: To determine the sociodemographic and clinical characteristics of a group of children with suspicion or confirmed diagnosis of pulmonary tuberculosis.Methodology: Fifty six children were studied at Hospital Universitario San Vicente de Paúl, in Medellín, Colombia, between July 2007 and December 2008. Pulmonarytuberculosis was confirmed according to the WHO criteria. Information was obtained from the patients themselves, their parents, and the hospital files. Results: In 38 of the 56 children (67.9%) pulmonary tuberculosis was confirmed. Their socioeconomic situation was poor in 87.5% of the cases; 55% came from the urban area of the city; 70% were mestizo, and 26.8%, Indians. Cough and fever were the predominant clinical manifestations. The positivity rate of diagnostic criteria was as follows: 53.6% for the epidemiological, 51.6% for the radiological, and 41.1% for the tuberculin test. Conclusion: Pulmonary tuberculosis continues to be of great importance in the pediatric population...