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1.
Med Clin North Am ; 108(1): 79-92, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37951657

ABSTRACT

Fever of unknown origin in adolescents is a challenging disease state for which potential underlying etiology can include infectious, non-infectious inflammatory, and malignancy processes. Careful and thorough history (including exposure history), serial examination, and targeted laboratory and imaging testing is critical for these patients. In adolescents in which an etiology is discovered, infectious etiology remains the most prevalent, followed by non-infectious inflammatory diseases. In patients with non-diagnostic overall reassuring work up, the prognosis is typically self-limiting and favorable.


Subject(s)
Communicable Diseases , Fever of Unknown Origin , Neoplasms , Adolescent , Humans , Fever of Unknown Origin/diagnosis , Fever of Unknown Origin/etiology , Fever of Unknown Origin/pathology , Communicable Diseases/complications , Prognosis , Neoplasms/complications
2.
Neuroimaging Clin N Am ; 34(1): 93-111, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37951708

ABSTRACT

Vasculitis is a complication of several infectious diseases affecting the central nervous system, which may result in ischemic and/or hemorrhagic stroke, transient ischemic attack, and aneurysm formation. Infectious agents may directly infect the endothelium causing vasculitis or indirectly affect the vessel wall through an immunological cascade. Clinical manifestations usually overlap with those of noninfectious vascular diseases, making diagnosis challenging. Neuroimaging enables the identification of inflammatory changes in intracranial vasculitis. In this article, we review the imaging features of infectious vasculitis of bacterial, viral, fungal and parasitic causes.


Subject(s)
Communicable Diseases , Vasculitis, Central Nervous System , Vasculitis , Humans , Communicable Diseases/complications , Vasculitis/complications , Cerebral Angiography , Neuroimaging , Vasculitis, Central Nervous System/diagnostic imaging , Vasculitis, Central Nervous System/complications
3.
J Infect Chemother ; 30(1): 67-70, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37657516

ABSTRACT

Hemophagocytic lymphohistiocytosis (HLH) is a highly lethal disease characterized by fever, cytopenia, splenomegaly, and hemophagocytosis. Whereas infectious diseases, malignant tumors, and autoimmune diseases are often triggers for HLH, reports of HLH associated with vaccination are limited. In this report, we describe a case of HLH in a 12-year-old female patient after simultaneous administration of the bivalent messenger RNA severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine and quadrivalent inactivated influenza vaccine. The patient presented to our hospital with fever on the day after vaccination. Considering the splenomegaly, cytopenia, hemophagocytosis in the bone marrow, and high ferritin level, HLH was diagnosed 12 days after vaccination. Various tests ruled out any infectious disease, malignant tumor, or autoimmune disease. The patient was treated only with 2 mg/kg/day of oral prednisolone, fever improved 13 days after vaccination, and blood test findings rapidly improved. Although HLH after SARS-CoV-2 vaccination or concomitant administration with influenza vaccination is still rare, we emphasize the importance of early HLH diagnosis when persistent fever is observed following vaccination.


Subject(s)
COVID-19 , Communicable Diseases , Influenza Vaccines , Lymphohistiocytosis, Hemophagocytic , Female , Humans , Child , Lymphohistiocytosis, Hemophagocytic/diagnosis , Lymphohistiocytosis, Hemophagocytic/drug therapy , Lymphohistiocytosis, Hemophagocytic/etiology , COVID-19 Vaccines/adverse effects , Influenza Vaccines/adverse effects , Splenomegaly , COVID-19/complications , SARS-CoV-2
4.
Methods Mol Biol ; 2724: 65-70, 2024.
Article in English | MEDLINE | ID: mdl-37987898

ABSTRACT

Most geminiviruses are not transmitted by mechanical inoculation. Therefore, pathogenicity and plant-pathogen interaction studies rely on agroinoculation using infectious clones, which involves cloning the geminiviral genome in a binary vector (see previous chapter for details). A suspension containing the infectious clone inserted into Agrobacterium tumefaciens cells is then inoculated into plants, i.e., agroinoculated. Below is a simple protocol for agroinoculation of an infectious geminivirus clone into plants.


Subject(s)
Communicable Diseases , Geminiviridae , Humans , Agrobacterium tumefaciens/genetics , Geminiviridae/genetics , Vaccination
5.
Methods Mol Biol ; 2724: 47-64, 2024.
Article in English | MEDLINE | ID: mdl-37987897

ABSTRACT

The production of geminiviral infectious clones provides a standardized inoculum for use in several host-virus studies. Geminiviruses present either one (monopartite) or two (bipartite) circular single-stranded DNA components, which commonly range from 2.6 to 2.8 kb. Cloning of a monomeric genome is useful for obtaining its precise sequence. For infectious clones, however, it is essential that more than one copy of the genome, more specifically of the origin of replication, is present in order to guarantee the production of full-length progeny DNA. Here, the complete process of preparing infectious geminiviral clones is described starting from the DNA extraction and selection of restriction endonucleases followed by two protocols for constructing dimeric clones: restriction endonuclease digestion and ligation (1) and Gibson Assembly (2).


Subject(s)
Communicable Diseases , Geminiviridae , Humans , DNA Restriction Enzymes/genetics , DNA, Single-Stranded/genetics , Geminiviridae/genetics , Clone Cells
6.
J Biomed Mater Res A ; 112(1): 53-64, 2024 01.
Article in English | MEDLINE | ID: mdl-37728144

ABSTRACT

Infectious diseases caused by pathogenic microorganisms are a significant burden on public health and the economic stability of societies all over the world. The appearance of drug-resistant bacteria has severely blocked the effectiveness of conventional antibiotics. Therefore, developing novel antibiotic-free strategies to combat bacteria holds huge potential for maximizing validity and minimizing the risk of enhancing bacterial resistance. Herein, a cypate-loaded hollow mesoporous Prussian blue nanoparticles (Cy-HMPBs) was built to achieve the PDT/PTT synergistic antimicrobial therapy. The carbomer hydrogel (CH) was combined with the Cy-HMPBs to form a nanoparticle/hydrogel therapeutic system (Cy-HMPBs/CH) to reach the goal of local delivery of antimicrobial cargo. The low concentration of Cy-HMPBs/CH receives over 99% of antimicrobial ability against Escherichia coli and Staphylococcus aureus upon near-infrared (NIR) irradiation. More importantly, Cy-HMPBs/CH has favorable biocompatibility and can play therapeutic effects only after laser irradiation, indicating the on-demand therapy at the targeted region to avert side effects on healthy tissue. This study provides ideas for the design of an antibiotic-free antimicrobial strategy against infectious diseases.


Subject(s)
Communicable Diseases , Nanoparticles , Photochemotherapy , Humans , Photothermal Therapy , Hydrogels , Anti-Bacterial Agents/pharmacology
7.
J Infect Chemother ; 30(1): 34-39, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37714267

ABSTRACT

INTRODUCTION: Zifanocycline (KBP-7072) is a novel aminomethylcycline antibiotic with a broad spectrum of antibacterial activity. This study determined the pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of zifanocycline in mice and the optimal PK/PD index for efficacy against Acinetobacter baumannii in a neutropenic murine thigh infection model. METHODS: Zifanocycline PK properties were characterized in plasma after single-dose subcutaneous injection in healthy mice at doses of 1, 4, 16, 64, and 256 mg/kg. PK/PD analyses were performed with zifanocycline against 8 clinical A. baumannii isolates in a neutropenic murine thigh infection model. RESULTS: Plasma total and free drug Cmax, AUC0-inf, and AUC0-24 increased with dose, where Cmax of total drug was 0.12-25.2 mg/L, AUC0-inf was 1.13-234 h*mg/L, AUC0-24 was 1.09-225 h*mg/L, and free drug Cmax was 0.03-5.68 mg/L, AUC0-inf was 0.25-52.6 h*mg/L, and AUC0-24 was 0.25-50.5 h*mg/L. MICs of zifanocycline against A. baumannii ranged from 0.06 to 0.5 mg/L, with significant activity against all 8 strains. Average daily doses of zifanocycline to achieve a static, 1-log10 kill, and 2-log10 kill effect were projected to be 6.92, 9.63, and 13.22 mg/kg, and the mean fAUC/MIC ratios were 6.91, 9.10, and 12.60, respectively. AUC/MIC was the optimal PK/PD index of zifanocycline against A. baumannii. CONCLUSION: The in vivo efficacy results and PK/PD analyses support the design of optimal dosing regimens in clinical studies and assist with determining clinical breakpoints for zifanocycline.


Subject(s)
Acinetobacter baumannii , Communicable Diseases , Neutropenia , Animals , Mice , Thigh , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use
8.
J Infect Chemother ; 30(1): 1-6, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37717609

ABSTRACT

INTRODUCTION: Infection and mortality rates caused by the coronavirus infectious disease 2019 (COVID-19) pandemic were high. However, the influence of the COVID-19 pandemic on the clinical burden in medical facilities remains to be clarified in Japan. MATERIALS AND METHODS: This study used a questionnaire-based web survey to clarify how the COVID-19 pandemic affected infectious disease practice and infection control. The questionnaire was sent to healthcare professionals at nationwide medical facilities between January 13, 2023, and February 15, 2023. RESULTS: Responses were obtained from 1784 healthcare professionals throughout Japan. Hospital management of COVID-19 patients was the responsibility of 96.5% of respondents. Furthermore, 75.1% had experienced nosocomial spread of COVID-19. Manuals and infection control measures for COVID-19 have been arranged in most facilities. In many facilities, the timing of an infected employee's return to work was determined in accordance with the isolation period for coronavirus-positive patients with symptoms established by the Ministry of Health, Labor and Welfare in Japan. Approximately 30% of respondents reported that caring for COVID-19 patients, including the use of personal protective equipment, was their most stressful job. Approximately 50% of the respondents reported an increase in overtime hours. Approximately 90% of facilities are now capable of performing COVID-19 testing onsite. CONCLUSION: Infection control for COVID-19 has been improved, and testing equipment for SARS-CoV-2 has been prepared. Patient care-related burdens and burdens caused by having to compensate for vacancies due to infected staff members have increased. In the future, a reduction in workload and role sharing should be considered.


Subject(s)
COVID-19 , Communicable Diseases , Humans , Pandemics/prevention & control , COVID-19 Testing , Japan/epidemiology , COVID-19/epidemiology , Infection Control , Surveys and Questionnaires
9.
J Ethnopharmacol ; 319(Pt 3): 117243, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-37777025

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Xingbei antitussive granules (XB) is a classic Chinese Medicine prescription for treating post-infectious cough(PIC), based on the Sanao Decoction from Formularies of the Bureau of People's Welfare Pharmacies in the Song Dynasty and Jiegeng decoction from Essentials of the Golden Chamber in the Han Dynasty. However, the therapeutic effects and pharmacological mechanisms are still ambiguous. In the present study, we endeavored to elucidate these underlying mechanisms. AIMS OF THE STUDY: This study aimed to explore the potential impact and mechanism of XB on PIC, and provide a scientific basis for its clinical application. MATERIALS AND METHODS: Cigarette smoking (CS) combined with lipopolysaccharide (LPS) nasal drops were administered to induce the PIC guinea pig with cough hypersensitivity status. Subsequently, the model guinea pigs were treated with XB and the cough frequency was observed by the capsaicin cough provocation test. The pathological changes of lung tissue were assessed by HE staining, and the levels of inflammatory mediators, mast cell degranulating substances, and neuropeptides were detected. The protein and mRNA expression of transient receptor potential vanilloid type 1(TRPV1), proteinase-activated receptor2(PAR2), and protein kinase C (PKC) were measured by Immunohistochemical staining, Western blot, and RT-qPCR. Changes in the abundance and composition of respiratory bacterial microbiota were determined by 16S rRNA sequencing. RESULTS: After XB treatment, the model guinea pigs showed a dose-dependent decrease in cough frequency, along with a significant alleviation in inflammatory infiltration of lung tissue and a reduction in inflammatory mediators. In addition, XB high-dose treatment significantly decreased the levels of mast cell Tryptase as well as ß-hexosaminidase (ß-Hex) and downregulated the expression of TRPV1, PAR2, and p-PKC. Simultaneously, levels of neuropeptides like substance P (SP), calcitonin gene-related peptide (CGRP), neurokinin A (NKA), and nerve growth factor (NGF) were improved. Besides, XB also can modulate the structure of respiratory bacterial microbiota and restore homeostasis. CONCLUSION: XB treatment alleviates cough hypersensitivity and inflammatory responses, inhibits the degranulation of mast cells, and ameliorates neurogenic inflammation in PIC guinea pigs whose mechanism may be associated with the inhibition of Tryptase/PAR2/PKC/TRPV1 and the recovery of respiratory bacterial microbiota.


Subject(s)
Antitussive Agents , Communicable Diseases , Humans , Guinea Pigs , Animals , Swine , Antitussive Agents/pharmacology , Antitussive Agents/therapeutic use , Cough/drug therapy , Tryptases , RNA, Ribosomal, 16S , Inflammation Mediators , TRPV Cation Channels
10.
Environ Res ; 240(Pt 2): 117395, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37838198

ABSTRACT

BACKGROUND: Epidemiological nowcasting traditionally relies on count surveillance data. The availability and quality of such count data may vary over time, limiting representation of true infections. Wastewater data correlates with traditional surveillance data and may provide additional value for nowcasting disease trends. METHODS: We obtained SARS-CoV-2 case, death, wastewater, and serosurvey data for Jefferson County, Kentucky (USA), between August 2020 and March 2021, and parameterized an existing nowcasting model using combinations of these data. We assessed the predictive performance and variability at the sewershed level and compared the effects of adding or replacing wastewater data to case and death reports. FINDINGS: Adding wastewater data minimally improved the predictive performance of nowcasts compared to a model fitted to case and death data (Weighted Interval Score (WIS) 0.208 versus 0.223), and reduced the predictive performance compared to a model fitted to deaths data (WIS 0.517 versus 0.500). Adding wastewater data to deaths data improved the nowcasts agreement to estimates from models using cases and deaths data. These findings were consistent across individual sewersheds as well as for models fit to the aggregated total data of 5 sewersheds. Retrospective reconstructions of epidemiological dynamics created using different combinations of data were in general agreement (coverage >75%). INTERPRETATION: These findings show wastewater data may be valuable for infectious disease nowcasting when clinical surveillance data are absent, such as early in a pandemic or in low-resource settings where systematic collection of epidemiologic data is difficult.


Subject(s)
Communicable Diseases , Wastewater , Humans , Kentucky/epidemiology , Retrospective Studies , Pandemics
11.
J Intensive Care Med ; 39(1): 59-68, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37455413

ABSTRACT

BACKGROUND: There is little information comparing the performance of community acquired central nervous system infections (CNSI) treatment by intensive care units (ICUs) specialized in infectious diseases with treatment at other ICUs. Our objective was to reduce these gaps, creating bases for benchmarking and future case-mix classification. METHODS: This is a retrospective observational cohort of 785 admissions with 82 cases of CNSI admitted to the ICU of an important Brazilian referral center for infectious diseases (INI) between January 2012 and January 2019. Comparisons were made to data retrospectively collected from the 303,500 intensive care admissions from the Brazilian state health care system included in the Epimed Monitor database. Clinical, epidemiologic, and performance indicators: the standardized mortality rate (SMR) and the standardized resource use rate per ICU surviving patient (SRU) were collected. RESULTS: Case-mix infections profile and SMR/SRU data. SUS Mixed medical/surgical ICUs: SMR = 1.26, SRU = 1.59; SUS Neurological ICUs: SMR = 1.17, SRU = 2.23; INI ICU: SMR = 1.1, SRU = 1.1; INI ICU CNSI patients: SMR = 0.95, SRU = 1.01. CONCLUSIONS: Severe patients with CNSI can be efficiently and effectively treated in an ICU specialized in infectious diseases when compared to mixed medical/surgical and neurological ICUs from the public health system. At the same time, we provided profiling and a case-mix that can help and encourage benchmarking by other institutions and other countries.


Subject(s)
Central Nervous System Infections , Communicable Diseases , Humans , Benchmarking , Retrospective Studies , Central Nervous System Infections/therapy , Intensive Care Units
12.
Arq. ciências saúde UNIPAR ; 27(2): 737-753, Maio-Ago. 2023.
Article in Portuguese | LILACS | ID: biblio-1424914

ABSTRACT

Objetivo: Avaliar as tendências e associações relacionadas as coberturas e internações por condições sensíveis à atenção primária à saúde no município de Fortaleza/Ceará/Brasil, no período de 2015 a 2021. Métodos: Estudo transversal com dados secundários (Sistema de Informações Hospitalares do Sistema Único de Saúde, E- gestor atenção básica e o Instituto Brasileiro de Geografia e Estatística). Utilizou-se o coeficiente de correlação de Pearson para as associações. Resultados: Foram registrados 176.330 internações por condições sensíveis, totalizando 8 principais, correspondendo a 78.5% do total. Obteve-se correlação inversa significativa entre a cobertura de atenção primária e internações por condições sensíveis: r=-0.86, (IC95%: -0.91/-0.61); p<0.001, bem como uma correlação moderada com cobertura de agente comunitário e internações (r=-0.59 (IC95%: -0.68/-0.54); p<0.001) Conclusão: O aumento das internações por condições sensíveis está diretamente relacionado com a cobertura da atenção primária. Além disso, enfrenta-se uma dupla carga de doenças, coexistindo as doenças infecciosas/parasitárias em concomitância com as crônicas.


Objective: To assess trends and associations related to coverage and hospitalizations for conditions sensitive to primary health care in the city of Fortaleza/Ceará/Brazil, from 2015 to 2021. Methods: Cross-sectional study with secondary data (Hospital Information System of the National Unified Health System, E- manager for primary care and the Brazilian Institute of Geography and Statistics). Pearson's correlation coefficient was used to measure associations. Results: 176,330 hospitalizations for sensitive conditions were recorded, totaling 8 main ones, corresponding to 78.5% of the total. A significant inverse correlation was obtained between primary care coverage and hospitalizations for sensitive conditions: r=-0.86, (95%CI: -0.91/-0.61); p<0.001, as well as a moderate correlation with community agent coverage and hospitalizations (r=-0.59 (95%CI: -0.68/-0.54); p<0.001) Conclusion: The increase in hospitalizations for sensitive conditions is directly associated to the primary care coverage. In addition, there is a double burden of disease, with infectious/parasitic diseases coexisting with chronic ones.


Evaluar las tendencias y asociaciones relacionadas con la cobertura y hospitalizaciones por condiciones sensibles a la atención primaria de salud en la ciudad de Fortaleza/Ceará/Brasil de 2015 a 2021. Métodos: Estudio transversal con datos secundarios (Sistema de Informações Hospitalares do Sistema Único de Saúde, E-gestor atenção básica e Instituto Brasileiro de Geografia e Estatística). Se utilizó el coeficiente de correlación de Pearson para las asociaciones. Resultados: Hubo 176.330 hospitalizaciones por condiciones sensibles, totalizando 8 condiciones principales, correspondiendo a 78,5% del total. Se obtuvo una correlación inversa significativa entre la cobertura de atención primaria y las hospitalizaciones por afecciones sensibles: r=- 0,86, (IC 95%: -0,91/-0,61); p<0,001, así como una correlación moderada con la cobertura de agentes comunitarios y las hospitalizaciones (r=-0,59 (IC 95%: -0,68/-0,54); p<0,001) Conclusión: El aumento de las hospitalizaciones por afecciones sensibles está directamente relacionado con la cobertura de atención primaria. Además, se enfrenta a una doble carga de enfermedad, coexistiendo enfermedades infecciosas/parasitarias en concomitancia con enfermedades crónicas.


Subject(s)
Primary Health Care , Ambulatory Care Sensitive Conditions , Hospitalization , Chronic Disease/epidemiology , Epidemiology , Communicable Diseases/epidemiology , Cross-Sectional Studies/methods , Hospital Information Systems/statistics & numerical data , Evaluation Study
13.
BMC Public Health ; 23(1): 2171, 2023 11 06.
Article in English | MEDLINE | ID: mdl-37932712

ABSTRACT

OBJECTIVES: To outline 44 major infectious diseases in the post-SARS (severe acute respiratory syndrome) in China and describe their long-term trends and changes by age, sex, epidemic season, and province. BACKGROUND: After the outbreak of severe acute respiratory syndrome (SARS) in 2003, with the change of infectious disease prevention and control system and the improvement of residents' quality of life, the incidence and mortality of infectious diseases have undergone major changes. METHODS: The data of 44 major infectious diseases in China from 2004 to 2018 were obtained from the monthly analysis report of the China Information System for Disease Control and Prevention (CISDCP) and the Public Health Science Data Center. Joinpoint r regression models were used to examine trends in incidence and mortality for 44 major and important infectious diseases from 2004 to 2018. RESULTS: From 2004 to 2018, 20,105, 500, 772 patients (10, 306, 546, 523 males and 9, 798, 954, 249 females) were diagnosed with 44 major infectious diseases. The overall incidence of 44 infectious diseases increased significantly from 294.6 per 100,000 people in 2004 to 479.1 per 100,000 people in 2010, with 7.9% APC (95% CI 5.2% -10.7%, P < 0.001), then slowed, and then increased to 561.2 per 100,000 people in 2018, with 1.5% APC (-0.1%-3.2%, P = 0.070). The overall mortality rose significantly, from 0.49 to 1.13 per 100,000 people between 2004 and 2011, with an APC increase of 11.6% (7.7% -15.6%, P < 0.001), and then remained stable until 2018. Among these, the prevalence of vaccine-preventable diseases and gastrointestinal & enteroviral diseases remained high and increased year by year. Patients with zoonotic diseases have the greatest risk of death, while patients with sexually transmitted and blood-borne diseases have the greatest number of deaths. Incidence rates vary considerably across geographic regions. Western China has a disproportionate burden of infectious diseases compared with eastern regions. CONCLUSIONS: After the event of SARS in 2003, infectious disease preventing and controlling model has undergone major changes in China, and certain achievements have been made in this field. Although overall morbidity and case fatality rates are still rising, they have leveled off. In reducing the disproportionate disease burden in the western region, expanding vaccination programs, preventing further increases in rates of sexually transmitted diseases, renewing efforts for emerging and persistent infectious diseases, and addressing seasonal and unpredictable outbreaks (such as the COVID-19 pandemic), there are still remain many challenges.


Subject(s)
Communicable Diseases , Pandemics , Male , Female , Humans , Quality of Life , Communicable Diseases/epidemiology , Morbidity , Incidence , China/epidemiology
14.
PLoS One ; 18(11): e0293968, 2023.
Article in English | MEDLINE | ID: mdl-37934734

ABSTRACT

The World Health Organization recommends test-and-treat interventions to curb and even eliminate epidemics of HIV, viral hepatitis, and sexually transmitted infections (e.g., chlamydia, gonorrhea, syphilis and trichomoniasis). Epidemic models show these goals are achievable, provided the participation of individuals in test-and-treat interventions is sufficiently high. We combine epidemic models and game theoretic models to describe individual's decisions to get tested for infectious diseases within certain epidemiological contexts, and, implicitly, their voluntary participation to test-and-treat interventions. We develop three hybrid models, to discuss interventions against HIV, HCV, and sexually transmitted infections, and the potential behavioral response from the target population. Our findings are similar across diseases. Particularly, individuals use three distinct behavioral patterns relative to testing, based on their perceived costs for testing, besides the payoff for discovering their disease status. Firstly, if the cost of testing is too high, then individuals refrain from voluntary testing and get tested only if they are symptomatic. Secondly, if the cost is moderate, some individuals will test voluntarily, starting treatment if needed. Hence, the spread of the disease declines and the disease epidemiology is mitigated. Thirdly, the most beneficial testing behavior takes place as individuals perceive a per-test payoff that surpasses a certain threshold, every time they get tested. Consequently, individuals achieve high voluntary testing rates, which may result in the elimination of the epidemic, albeit on temporary basis. Trials and studies have attained different levels of participation and testing rates. To increase testing rates, they should provide each eligible individual with a payoff, above a given threshold, each time the individual tests voluntarily.


Subject(s)
Communicable Diseases , Gonorrhea , HIV Infections , Sexually Transmitted Diseases , Syphilis , Humans , HIV Infections/epidemiology , Sexually Transmitted Diseases/diagnosis , Sexually Transmitted Diseases/epidemiology , Sexually Transmitted Diseases/prevention & control , Communicable Diseases/diagnosis , Communicable Diseases/epidemiology , Syphilis/epidemiology , Gonorrhea/epidemiology
15.
Math Biosci Eng ; 20(9): 16015-16032, 2023 08 04.
Article in English | MEDLINE | ID: mdl-37920000

ABSTRACT

Cholera, a severe gastrointestinal infection caused by the bacterium Vibrio cholerae, remains a major threat to public health, with a yearly estimated global burden of 2.9 million cases. Although most existing models for the disease focus on its population dynamics, the disease evolves from within-host processes to the population, making it imperative to link the multiple scales of the disease to gain better perspectives on its spread and control. In this study, we propose an immuno-epidemiological model that links the between-host and within-host dynamics of cholera. The immunological (within-host) model depicts the interaction of the cholera pathogen with the adaptive immune response. We distinguish pathogen dynamics from immune response dynamics by assigning different time scales. Through a time-scale analysis, we characterise a single infected person by their immune response. Contrary to other within-host models, this modelling approach allows for recovery through pathogen clearance after a finite time. Then, we scale up the dynamics of the infected person to construct an epidemic model, where the infected population is structured by individual immunological dynamics. We derive the basic reproduction number ($ \mathcal{R}_0 $) and analyse the stability of the equilibrium points. At the disease-free equilibrium, the disease will either be eradicated if $ \mathcal{R}_0 < 1 $ or otherwise persists. A unique endemic equilibrium exists when $ \mathcal{R}_0 > 1 $ and is locally asymptotically stable without a loss of immunity.


Subject(s)
Cholera , Communicable Diseases , Epidemics , Vibrio cholerae , Humans , Cholera/epidemiology , Cholera/microbiology , Models, Biological , Communicable Diseases/epidemiology
16.
Math Biosci Eng ; 20(9): 16083-16113, 2023 08 08.
Article in English | MEDLINE | ID: mdl-37920004

ABSTRACT

We introduce a two-strain model with asymmetric temporary immunity periods and partial cross-immunity. We derive explicit conditions for competitive exclusion and coexistence of the strains depending on the strain-specific basic reproduction numbers, temporary immunity periods, and degree of cross-immunity. The results of our bifurcation analysis suggest that, even when two strains share similar basic reproduction numbers and other epidemiological parameters, a disparity in temporary immunity periods and partial or complete cross-immunity can provide a significant competitive advantage. To analyze the dynamics, we introduce a quasi-steady state reduced model which assumes the original strain remains at its endemic steady state. We completely analyze the resulting reduced planar hybrid switching system using linear stability analysis, planar phase-plane analysis, and the Bendixson-Dulac criterion. We validate both the full and reduced models with COVID-19 incidence data, focusing on the Delta (B.1.617.2), Omicron (B.1.1.529), and Kraken (XBB.1.5) variants. These numerical studies suggest that, while early novel strains of COVID-19 had a tendency toward dramatic takeovers and extinction of ancestral strains, more recent strains have the capacity for co-existence.


Subject(s)
COVID-19 , Communicable Diseases , Humans , Communicable Diseases/epidemiology , Basic Reproduction Number , COVID-19/epidemiology
17.
Math Biosci Eng ; 20(9): 16114-16130, 2023 08 08.
Article in English | MEDLINE | ID: mdl-37920005

ABSTRACT

Under the background that asymptomatic virus carriers have infectivity for an infectious disease, we establish a difference equations model with vaccination and virus testing in this paper. Assuming that the vaccine is 100% effective for susceptible people but cannot stop the infectivity of asymptomatic virus carriers, we study how to combine vaccination and virus testing at the beginning of an epidemic to effectively block the spread of infectious disease in different population sizes. By considering the daily processing capacity of the vaccine and daily proportion of testing, the corresponding numerical simulation results are obtained. It is shown that when vaccine availability and virus testing capacity are insufficient, a reasonable combination of the above two measures can slow down or even block the spread of infectious disease. Single virus testing or vaccination can also block the spread of infectious disease, but this requires a lot of manpower, material and financial resources. When the daily proportion of virus testing is fixed, the ratio of the minimum daily processing capacity of vaccines used to block the spread of infectious disease to the corresponding population size is rather stable. It demonstrates that effective protective measures of the same infectious disease in countries and regions with different population sizes can be used as a reference. These results also provide a certain reference for decision makers on how to coordinate vaccines and virus testing resources to curb the spread of such an infectious disease in a certain population size.


Subject(s)
Communicable Diseases , Epidemics , Vaccines , Humans , Communicable Diseases/epidemiology , Vaccination/methods , Epidemics/prevention & control , Computer Simulation
18.
Math Biosci Eng ; 20(9): 16807-16823, 2023 08 23.
Article in English | MEDLINE | ID: mdl-37920035

ABSTRACT

Accurately modeling and predicting epidemic diseases is crucial to prevent disease transmission and reduce mortality. Due to various unpredictable factors, including population migration, vaccination, control efforts, and seasonal fluctuations, traditional epidemic models that rely on prior knowledge of virus transmission mechanisms may not be sufficient to forecast complex epidemics like coronavirus disease 2019(COVID-19). The application of traditional epidemiological models such as susceptible-exposed-infectious-recovered (SEIR) may face difficulties in accurately predicting such complex epidemics. Data-driven prediction approaches lack the ability to generalize and exhibit low accuracy on small datasets due to their reliance on large amounts of data without incorporating prior knowledge. To overcome this limitation, we introduce a flexible ensemble data-driven framework (Neural-SEIR) that "neuralizes" the SEIR model by approximating the core parameters through neural networks while preserving the propagation structure of SEIR. Neural-SEIR employs long short-term memory (LSTM) neural network to capture complex correlation features, exponential smoothing (ES) to model seasonal information, and prior knowledge from SEIR. By incorporating SEIR parameters into the neural network structure, Neural-SEIR leverages prior knowledge while updating parameters with real-world data. Our experimental results demonstrate that Neural-SEIR outperforms traditional machine learning and epidemiological models, achieving high prediction accuracy and efficiency in forecasting epidemic diseases.


Subject(s)
COVID-19 , Communicable Diseases , Epidemics , Humans , Communicable Diseases/epidemiology , Neural Networks, Computer , COVID-19/epidemiology
19.
Math Biosci Eng ; 20(9): 17520-17553, 2023 09 13.
Article in English | MEDLINE | ID: mdl-37920064

ABSTRACT

Zika is an infectious disease with multiple transmission routes, which is related to severe congenital disabilities, especially microcephaly, and has attracted worldwide concern. This paper aims to study the dynamic behavior and optimal control of the disease. First, we establish a stochastic reaction-diffusion model (SRDM) for Zika virus, including human-mosquito transmission, human-human sexual transmission, and vertical transmission of mosquitoes, and prove the existence, uniqueness, and boundedness of the global positive solution of the model. Then, we discuss the sufficient conditions for disease extinction and the existence of a stationary distribution of positive solutions. After that, three controls, i.e. personal protection, treatment of infected persons, and insecticides for spraying mosquitoes, are incorporated into the model and an optimal control problem of Zika is formulated to minimize the number of infected people, mosquitoes, and control cost. Finally, some numerical simulations are provided to explain and supplement the theoretical results obtained.


Subject(s)
Aedes , Communicable Diseases , Zika Virus Infection , Zika Virus , Animals , Humans , Zika Virus Infection/prevention & control , Infectious Disease Transmission, Vertical
20.
Sci Rep ; 13(1): 19143, 2023 11 06.
Article in English | MEDLINE | ID: mdl-37932342

ABSTRACT

The close relationship between infectious diseases and iron metabolism is well known, but a more detailed understanding based on current knowledge may provide new insights into the diagnosis and treatment of infectious diseases, considering the growing threat of antibiotic-resistant bacteria. This study investigated adult patients with bloodstream infections, temporal changes, and relationships between blood levels of iron and related markers, including hepcidin and lipocalin-2 (LCN2). We included 144 samples from 48 patients (mean age 72 years, 50% male), with 30 diagnosed with sepsis. During the acute phase of infection, blood levels of hepcidin and LCN2 increased rapidly, whereas iron levels decreased, with values in 95.8% of cases below the normal range (40-188 µg/dL). Later, hepcidin and LCN2 decreased significantly during the recovery phase, and the decreased iron concentrations were restored. In the case of persistent inflammation, iron remained decreased. Acute LCN2 levels were significantly higher in patients with sepsis (p < 0.01). Hypoferremia induced by increased hepcidin would reduce iron in the environment of extracellular pathogens, and the increased LCN2 would inhibit siderophores, resulting in the prevention of the pathogen's iron acquisition in each manner during the acute phase of bloodstream infection.


Subject(s)
Communicable Diseases , Sepsis , Humans , Male , Aged , Female , Hepcidins/metabolism , Lipocalin-2/metabolism , Iron/metabolism , Siderophores/metabolism
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