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This paper introduces a novel nonlinear fractal fractional model to comprehensively analyze influenza epidemics. By integrating fractional calculus and considering nonlinear interactions among individuals, the model utilizes the Fractal-Fractional (FF) operator. This operator, combining fractal and fractional calculus, establishes a unique framework for investigating influenza virus propagation dynamics and potential vaccination strategies. Amid growing concerns over influenza outbreaks, fractional derivatives are employed to address intricate challenges. The proposed model sheds light on virus spread dynamics and countermeasures. The integration of the FF operator enriches analysis, while the application of the fixed point theory of Schauder and Banach demonstrates solution existence and uniqueness. Model validation employs numerical simulations with MATLAB12̂ and the Adams–Bashforth method, confirming its ability to capture influenza propagation dynamics accurately. Ulam–Hyers stability techniques ensure the model’s reliability. Beyond its scientific contributions, the model underscores the significance of studying influenza epidemics via mathematical modeling in understanding disease dynamics and guiding effective intervention strategies. Through a synergy of mathematical innovation and epidemiological insights, this study establishes a robust foundation for more effective strategies against influenza epidemics. [ABSTRACT FROM AUTHOR]

COVID-19 is a fast-invading virus that quickly invaded the human body and made no human activity immune to its infections. The purpose of this study is to simulate the effects of COVID-19 on employment behaviour and vaccination's weight in the recovery process. Based on quarterly panel data from 43 nations from 2018 to 2020, we built an adaptive employment model. The major findings demonstrate that COVID-19 has negative and large net and second effects, with parameters of −7049 and −15,768 employees each quarter for 100,000 infected people, respectively. While immunization has a positive net effect of 10,900 employees every quarter, it has a negative second effect of −29,817 employees. This last result may look strange, but it is rational and demonstrates that immunizations modify employees' behaviour toward prevention measures, leading to actions such as resuming mobility, reopening, cancelling confinement, and so on, even though COVID-19 continues to spread. Demand, the labour force, the short-term multiplier, and immunization appear to have a positive and large impact on employment behaviour, while average labour productivity appears to have a negative impact. [ABSTRACT FROM AUTHOR]

In this paper, a stochastic SIQR epidemic model with vaccination effect is investigated. Our purpose is to study the dynamical behaviors of the model. First, the existence and uniqueness of the positive solution of the model is proved. Then, the dynamic properties of the model, such as extinction and persistence, are analyzed by regarding certain conditions on the parameters. Some sufficient conditions for extinction and persistence are given by using Itô's formula and martingale methods. The results show that low-intensity white noise may cause disease to spread, while high-intensity white noise may drive infective, quarantined individuals to extinction. Finally, numerical simulations are illustrated to support the theoretical analysis. [ABSTRACT FROM AUTHOR]

Fifty-seven stage 4 patients with refractory/relapsed neuroblastoma were enrolled in a phase I trial (Clinicaltrials.gov NCT01757626) using humanized anti-GD2 monoclonal antibody hu3F8 in combination with granulocyte-macrophage colony-stimulating factor. The influence of body weight and human anti-human antibody (HAHA) on the pharmacokinetics (PK) of hu3F8, and the effect of de novo anti-GD2 response on patient outcome were explored. Serum samples before hu3F8 infusion, and serially up to day 12 during treatment cycle #1, and at 5 min after each hu3F8 infusion for all subsequent cycles were collected. PK was analyzed using non-compartmental modeling. Immunogenicity was assayed by HAHA response, and vaccination effect by induced host anti-GD2 response measured periodically until disease progression or last followup. Progression-free and overall survival was estimated by the Kaplan-Meier method. Despite dosing being based on body weight, smaller patients had consistently lower area-under-the-curve and faster clearance over the 15 dose levels (0.9 to 9.6 mg/kg per treatment cycle) in this trial. Positive HAHA, defined by the upper limit of normal, when measured within 10 days from the last hu3F8 dose received, was associated with significantly lower serum hu3F8. Despite prior sensitization to other anti-GD2 antibody, e.g. mouse 3F8 or ch14.18, 75% of the patients never developed HAHA response even after getting more treatment cycles. Hu3F8 induced a de novo anti-GD2 response in patients, which was prognostic of progression-free survival. We conclude that hu3F8 had low immunogenicity. During treatment, positive HAHA and low body weight affected PK adversely, whereas induced anti-GD2 response was an outcome predictor.

Fifty-seven stage 4 patients with refractory/relapsed neuroblastoma were enrolled in a phase I trial (Clinicaltrials.gov NCT01757626) using humanized anti-GD2 monoclonal antibody hu3F8 in combination with granulocyte-macrophage colony-stimulating factor. The influence of body weight and human anti-human antibody (HAHA) on the pharmacokinetics (PK) of hu3F8, and the effect of de novo anti-GD2 response on patient outcome were explored. Serum samples before hu3F8 infusion, and serially up to day 12 during treatment cycle #1, and at 5 min after each hu3F8 infusion for all subsequent cycles were collected. PK was analyzed using non-compartmental modeling. Immunogenicity was assayed by HAHA response, and vaccination effect by induced host anti-GD2 response measured periodically until disease progression or last followup. Progression-free and overall survival was estimated by the Kaplan-Meier method. Despite dosing being based on body weight, smaller patients had consistently lower area-under-the-curve and faster clearance over the 15 dose levels (0.9 to 9.6 mg/kg per treatment cycle) in this trial. Positive HAHA, defined by the upper limit of normal, when measured within 10 days from the last hu3F8 dose received, was associated with significantly lower serum hu3F8. Despite prior sensitization to other anti-GD2 antibody, e.g. mouse 3F8 or ch14.18, 75% of the patients never developed HAHA response even after getting more treatment cycles. Hu3F8 induced a de novo anti-GD2 response in patients, which was prognostic of progression-free survival. We conclude that hu3F8 had low immunogenicity. During treatment, positive HAHA and low body weight affected PK adversely, whereas induced anti-GD2 response was an outcome predictor. [ABSTRACT FROM PUBLISHER]