Projected Impact of Nonpharmacologic Management of Stage 1 Hypertension Among Lower-Risk US Adults.

BACKGROUND: The 2017 American College of Cardiology/American Heart Association blood pressure guideline classified 31 million US adults as having stage 1 hypertension and recommended clinicians provide counseling on behavioral change to the low-risk portion of this group. However, nationwide reductions in cardiovascular disease (CVD) and associated health care expenditures achievable by nonpharmacologic therapy remain unquantified. METHODS: We simulated interventions on a target population of US adults aged 35 to 64 years, identified from the 2015-2018 National Health and Nutrition Examination Survey, with low-risk stage 1 systolic hypertension: that is, untreated systolic blood pressure 130 to 139 mm Hg with diastolic BP <90 mm Hg; no history of CVD, diabetes, or chronic kidney disease; and a low 10-year risk of CVD. We used meta-analyses and trials to estimate the effects of population-level behavior modification on systolic blood pressure. We assessed the extent to which restricting intervention to those in regular contact with clinicians might prevent the delivery of nonpharmacologic therapy. RESULTS: Controlling systolic blood pressure to <130 mm Hg among the 8.8 million low-risk US adults with stage 1 hypertension could prevent 26 100 CVD events, avoid 2900 deaths, and save $1.7 billion in total direct health care costs over 10 years. Adoption of the Dietary Approaches to Stop Hypertension diet could prevent 28 000 CVD events. Other nonpharmacologic interventions could avert between 3800 and 19 500 CVD events. However, only 51% of men and 75% of women regularly interacted with clinicians for counseling opportunities. CONCLUSIONS: Among low-risk adults with stage 1 hypertension, substantial benefits to cardiovascular health could be achieved through public policy that promotes the adoption of nonpharmacologic therapy.

Dermal injury drives a skin to gut axis that disrupts the intestinal microbiome and intestinal immune homeostasis in mice.

The composition of the microbial community in the intestine may influence the functions of distant organs such as the brain, lung, and skin. These microbes can promote disease or have beneficial functions, leading to the hypothesis that microbes in the gut explain the co-occurrence of intestinal and skin diseases. Here, we show that the reverse can occur, and that skin directly alters the gut microbiome. Disruption of the dermis by skin wounding or the digestion of dermal hyaluronan results in increased expression in the colon of the host defense genes Reg3 and Muc2, and skin wounding changes the composition and behavior of intestinal bacteria. Enhanced expression Reg3 and Muc2 is induced in vitro by exposure to hyaluronan released by these skin interventions. The change in the colon microbiome after skin wounding is functionally important as these bacteria penetrate the intestinal epithelium and enhance colitis from dextran sodium sulfate (DSS) as seen by the ability to rescue skin associated DSS colitis with oral antibiotics, in germ-free mice, and fecal microbiome transplantation to unwounded mice from mice with skin wounds. These observations provide direct evidence of a skin-gut axis by demonstrating that damage to the skin disrupts homeostasis in intestinal host defense and alters the gut microbiome.

CCR2-dependent CX3CR1+ colonic macrophages promote Enterococcus faecalis dissemination.

Enterococci are common commensal bacteria that colonize the gastrointestinal tracts of most mammals, including humans. Importantly, these bacteria are one of the leading causes of nosocomial infections. This study examined the role of colonic macrophages in facilitating Enterococcus faecalis infections in mice. We determined that depletion of colonic phagocytes resulted in the reduction of E. faecalis dissemination to the gut-draining mesenteric lymph nodes. Furthermore, we established that trafficking of monocyte-derived CX3CR1-expressing macrophages contributed to E. faecalis dissemination in a manner that was not reliant on CCR7, the conventional receptor involved in lymphatic migration. Finally, we showed that E. faecalis mutants with impaired intracellular survival exhibited reduced dissemination, suggesting that E. faecalis can exploit host immune cell migration to disseminate systemically and cause disease. Our findings indicate that modulation of macrophage trafficking in the context of antibiotic therapy could serve as a novel approach for preventing or treating opportunistic infections by disseminating enteric pathobionts like E. faecalis.

A serum-induced gene signature in hepatocytes is associated with pediatric nonalcoholic fatty liver disease.

OBJECTIVE: Pediatric nonalcoholic fatty liver disease (NAFLD) is a growing problem, but its underlying mechanisms are poorly understood. We used transcriptomic reporter cell assays to investigate differences in transcriptional signatures induced in hepatocyte reporter cells by the sera of children with and without NAFLD. METHODS: We studied serum samples from 45 children with NAFLD and 28 children without NAFLD. The sera were used to induce gene expression in cultured HepaRG cells and RNA-sequencing was used to determine gene expression. Computational techniques were used to compare gene expression patterns. RESULTS: Sera from children with NAFLD induced the expression of 195 genes that were significantly differentially expressed in hepatocytes compared to controls with obesity. NAFLD was associated with increased expression of genes promoting inflammation, collagen synthesis, and extracellular matrix remodeling. Additionally, there was lower expression of genes involved in endobiotic and xenobiotic metabolism, and downregulation of peroxisome function, oxidative phosphorylation, and xenobiotic, bile acid, and fatty acid metabolism. A 13-gene signature, including upregulation of TREM1 and MMP1 and downregulation of CYP2C9, was consistently associated with all diagnostic categories of pediatric NAFLD. CONCLUSION: The extracellular milieu of sera from children with NAFLD induced specific gene profiles distinguishable by a hepatocyte reporter system. Circulating factors may contribute to inflammation and extracellular matrix remodeling and impair xenobiotic and endobiotic metabolism in pediatric NAFLD.

Tuft cells mediate commensal remodeling of the small intestinal antimicrobial landscape.

Succinate produced by the commensal protist Tritrichomonas musculis (T. mu) stimulates chemosensory tuft cells, resulting in intestinal type 2 immunity. Tuft cells express the succinate receptor SUCNR1, yet this receptor does not mediate antihelminth immunity nor alter protist colonization. Here, we report that microbial-derived succinate increases Paneth cell numbers and profoundly alters the antimicrobial peptide (AMP) landscape in the small intestine. Succinate was sufficient to drive this epithelial remodeling, but not in mice lacking tuft cell chemosensory components required to detect this metabolite. Tuft cells respond to succinate by stimulating type 2 immunity, leading to interleukin-13-mediated epithelial and AMP expression changes. Moreover, type 2 immunity decreases the total number of mucosa-associated bacteria and alters the small intestinal microbiota composition. Finally, tuft cells can detect short-term bacterial dysbiosis that leads to a spike in luminal succinate levels and modulate AMP production in response. These findings demonstrate that a single metabolite produced by commensals can markedly shift the intestinal AMP profile and suggest that tuft cells utilize SUCNR1 and succinate sensing to modulate bacterial homeostasis.

Gut microbiota and metabolites drive chronic sickle cell disease pain.

Pain is a debilitating symptom and leading reason for hospitalization of individuals with sickle cell disease. Chronic sickle cell pain is poorly managed because the biological basis is not fully understood. Using transgenic sickle cell mice and fecal material transplant, we determined that the gut microbiome drives persistent sickle cell pain. In parallel patient and mouse analyses, we identified bilirubin as one metabolite that induces sickle cell pain by altering vagus nerve activity. Furthermore, we determined that decreased abundance of the gut bacteria Akkermansia mucinophila is a critical driver of chronic sickle cell pain. These experiments demonstrate that the sickle cell gut microbiome drives chronic widespread pain and identify bacterial species and metabolites that should be targeted for chronic sickle cell disease pain management.

Fractional-order model on vaccination and severity of COVID-19.

Coronavirus disease 2019 (COVID-19), an infection that is highly contagious. It has a regrettable effect on the world and has resulted in more than 4.6 million deaths to date (July 2021). For this contagious disease, numerous nations implemented control measures. Every country has vaccination programs in place to achieve the best results. This research is done in two stages, including partial and complete vaccination, to enhance the efficiency and effectiveness of the vaccination. Our study found that receiving this vaccination lowers the risk of contracting a disease and its side effects, such as severity, hospitalization, need for oxygen, admission to the intensive care unit, and infection-related death. Taking into account, the system is built using fractional-order Caputo sense nonlinear differential equations. A basic reproduction number is calculated to determine the transmission rate. The bifurcation analysis predicts chaotic behavior of a system for this threshold value. The suggested system's recovery rate is optimized using fractional optimum controls. For the fractional-order differential equation, numerical results are simulated using MATLAB software using real-validated data (July 2021).

Projected Impact of Nonpharmacologic Management of Stage 1 Hypertension Among Lower-Risk US Adults.

Background: The 2017 American College of Cardiology (ACC)/American Heart Association (AHA) guidelines newly classified 31 million US adults as having stage 1 hypertension. The ACC/AHA guidelines recommend behavioral change without pharmacology for the low-risk portion of this group. However, the nationwide reduction in cardiovascular disease (CVD) and associated healthcare expenditures achievable by evidence-based dietary improvements, sustained weight loss, adequate physical activity, and alcohol moderation remain unquantified. We estimated the effect of systolic BP (SBP) control and behavioral changes on 10-year CVD outcomes and costs. Methods: We used the CVD Policy Model to simulate CVD events, mortality, and healthcare costs among US adults aged 35-64. We simulated interventions on a target population, identified from the 2015-2018 National Health and Nutrition Examination Survey, with low-risk stage 1 systolic hypertension: defined as untreated SBP 130-139 mmHg and diastolic BP <90 mmHg; no history of CVD, diabetes, or chronic kidney disease; and low 10-year risk of CVD. We used published meta-analyses and trials to estimate the effects of behavior modification on SBP. We assessed the extent to which intermittent healthcare utilization or partial uptake of nonpharmacologic therapy would decrease CVD events prevented. Results: Controlling SBP to <130 mmHg among the estimated 8.8 million U.S. adults (51% women) in the target population could prevent 26,100 CVD events, avoid 2,900 deaths, and save $1.6 billion in healthcare costs over 10 years. The Dietary Approaches to Stop Hypertension (DASH) diet could prevent 16,000 CVD events among men and 12,000 among women over a decade. Other nonpharmacologic interventions could avert between 3,700 and 19,500 CVD events. However, only 5.5 million (61%) of the target population regularly utilized healthcare where recommended clinician counseling could occur. Conclusions: As only two-thirds of U.S. adults with Stage 1 hypertension regularly receive medical care, substantial benefits to cardiovascular health and associated costs may only stem from policies that promote widespread adoption and sustained adherence of nonpharmacologic therapy. Future work should quantify the population-level costs, benefits, and efficacy of improving the food system and local infrastructure on health behavior change.

Lactiplantibacillus plantarum 299v supplementation modulates ß-cell ER stress and antioxidative defense pathways and prevents type 1 diabetes in gluten-free BioBreeding rats.

The increasing incidence of Type 1 diabetes has coincided with the emergence of the low-fiber, high-gluten Western diet and other environmental factors linked to dysbiosis. Since Lactiplantibacillus plantarum 299 v (Lp299v) supplementation improves gut barrier function and reduces systemic inflammation, we studied its effects in spontaneously diabetic DRlyp/lyp rats provided a normal cereal diet (ND) or a gluten-free hydrolyzed casein diet (HCD). All rats provided ND developed diabetes (62.5±7.7 days); combining ND with Lp299v did not improve survival. Diabetes was delayed by HCD (72.2±9.4 days, p = .01) and further delayed by HCD+Lp299v (84.9±14.3 days, p < .001). HCD+Lp299v pups exhibited increased plasma propionate and butyrate levels, which correlated with enriched fecal Bifidobacteriaceae and Clostridiales taxa. Islet transcriptomic and histologic analyses at 40-days of age revealed that rats fed HCD expressed an autophagy profile, while those provided HCD+Lp299v expressed ER-associated protein degradation (ERAD) and antioxidative defense pathways, including Nrf2. Exposing insulinoma cells to propionate and butyrate promoted the antioxidative defense response but did not recapitulate the HCD+Lp299v islet ERAD transcriptomic profile. Here, both diet and microbiota influenced diabetes susceptibility. Moreover, Lp299v supplement modulated antioxidative defense and ER stress responses in ß-cells, potentially offering a new therapeutic direction to thwart diabetes progression and preserve insulin secretion.

Group 3 innate lymphoid cells require BATF to regulate gut homeostasis in mice.

Group 3 innate lymphoid cells (ILC3s) are crucial for the maintenance of host-microbiota homeostasis in gastrointestinal mucosal tissues. The mechanisms that maintain lineage identity of intestinal ILC3s and ILC3-mediated orchestration of microbiota and mucosal T cell immunity are elusive. Here, we identified BATF as a gatekeeper of ILC3 homeostasis in the gut. Depletion of BATF in ILC3s resulted in excessive interferon-γ production, dysbiosis, aberrant T cell immune responses, and spontaneous inflammatory bowel disease (IBD), which was considerably ameliorated by the removal of adaptive immunity, interferon-γ blockade, or antibiotic treatment. Mechanistically, BATF directly binds to the cis-regulatory elements of type 1 effector genes, restrains their chromatin accessibility, and inhibits their expression. Conversely, BATF promotes chromatin accessibility of genes involved in MHCII antigen processing and presentation pathways, which in turn directly promotes the transition of precursor ILC3s to MHCII+ ILC3s. Collectively, our findings reveal that BATF is a key transcription factor for maintaining ILC3 stability and coordinating ILC3-mediated control of intestinal homeostasis.

Probiotic normalization of systemic inflammation in siblings of type 1 diabetes patients: an open-label pilot study.

The incidence of type 1 diabetes (T1D) has increased, coinciding with lifestyle changes that have likely altered the gut microbiota. Dysbiosis, gut barrier dysfunction, and elevated systemic inflammation consistent with microbial antigen exposure, have been associated with T1D susceptibility and progression. A 6-week, single-arm, open-label pilot trial was conducted to investigate whether daily multi-strain probiotic supplementation could reduce this familial inflammation in 25 unaffected siblings of T1D patients. Probiotic supplementation was well-tolerated as reflected by high participant adherence and no adverse events. Community alpha and beta diversity were not altered between the pre- and post-supplement stool samplings. However, LEfSe analyses identified post-supplement enrichment of the family Lachnospiraceae, producers of the anti-inflammatory short chain fatty acid butyrate. Systemic inflammation was measured by plasma-induced transcription and quantified with a gene ontology-based composite inflammatory index (I.I.com). Post-supplement I.I.com was significantly reduced and pathway analysis predicted inhibition of numerous inflammatory mediators and activation of IL10RA. Subjects with the greatest post-supplement reduction in I.I.com exhibited significantly lower CD4+ CD45RO+ (memory):CD4+ CD45RA+ (naïve) T-cell ratios after supplementation. Post-supplement IL-12p40, IL-13, IL-15, IL-18, CCL2, and CCL24 plasma levels were significantly reduced, while post-supplement butyrate levels trended 1.4-fold higher. Probiotic supplementation may modify T1D susceptibility and progression and warrants further study.

Modelling COVID-19 transmission in the United States through interstate and foreign travels and evaluating impact of governmental public health interventions.

Background: The first case of COVID-19 was reported in Wuhan, China in December 2019. The disease has spread to 210 countries and has been labelled as a pandemic by the World Health Organization (WHO). Modelling, evaluating, and predicting the rate of disease transmission is crucial in understanding optimal methods for prevention and control. Our aim is to assess the impact of interstate and foreign travel and public health interventions implemented by the United States government in response to the COVID-19 pandemic. Methods: A disjoint mutually exclusive compartmental model was developed to study transmission dynamics of the novel coronavirus. A system of nonlinear differential equations was formulated and the basic reproduction number R 0 was computed. Stability of the model was evaluated at the equilibrium points. Optimal controls were applied in the form of travel restrictions and quarantine. Numerical simulations were conducted. Results: Analysis shows that the model is locally asymptomatically stable, at endemic and foreigners free equilibrium points. Without any mitigation measures, infectivity and subsequent hospitalization of the population increased. When interstate and foreign travel was restricted and the population placed under quarantine, the probability of exposure and subsequent infection decreased significantly; furthermore, the recovery rate increased substantially. Conclusion: Interstate and foreign travel restrictions, in addition to quarantine, are necessary in effectively controlling the pandemic. The United States has controlled COVID-19 spread by implementing quarantine and restricting foreign travel. The government can further strengthen restrictions and reduce spread within the nation more effectively by implementing restrictions on interstate travel.

The association between physical health-related quality of life, physical functioning, and risk of contralateral breast cancer among older women.

BACKGROUND: Physical limitations prior to cancer diagnosis may lead to suboptimal health outcomes. Our objective was to evaluate the impacts of poor physical health-related quality of life (HRQOL) and physical functioning (PF) on the risk of contralateral breast cancer (CBC). METHODS: We performed a nested case-control study of women with invasive unilateral breast cancer (UBC) who did not receive prophylactic contralateral mastectomy using the Surveillance, Epidemiology and End Results Medicare Health Outcomes Survey data resource. Among 2938 women aged ≥ 65 years diagnosed with first stage I-III UBC between 1997 and 2011, we identified 100 subsequent CBC cases and 915 matched controls without CBC using incidence density sampling without replacement. Pre-diagnosis physical HRQOL and PF were determined using Medical Outcomes Trust Short Form-36 (SF-36)/Veterans Rand 12-Item Health Survey (VR-12) responses within 2 years prior to first UBC diagnosis. We estimated adjusted odds ratios (OR) and 95% confidence intervals (CI) using conditional logistic regression models. RESULTS: Cases and controls were similar with respect to comorbidities, stage, surgery, and radiation treatments, but differed by hormone receptor status (ER/PR-negative, 23% and 11%, respectively) of first UBC. Cases had modestly lower mean pre-diagnosis physical HRQOL (- 1.8) and PF (- 2.2) scores. In multivariable models, we observed an increased CBC risk associated with low physical HRQOL (lowest vs. highest quartile, OR = 1.8; 95% CI 0.8-4.3), but CIs included 1.0. Low PF was associated with a 2.7-fold (95% CI 1.1-6.7) increased CBC risk. CONCLUSIONS: Findings indicate that low physical HRQOL, specifically poor PF, is associated with CBC risk. Efforts to understand and minimize declines in PF post-breast cancer are well motivated.

Skin inflammation activates intestinal stromal fibroblasts and promotes colitis.

Inflammatory disorders of the skin are frequently associated with inflammatory bowel diseases (IBDs). To explore mechanisms by which these organs communicate, we performed single-cell RNA-Seq analysis on fibroblasts from humans and mice with IBD. This analysis revealed that intestinal inflammation promoted differentiation of a subset of intestinal stromal fibroblasts into preadipocytes with innate antimicrobial host defense activity. Furthermore, this process of reactive adipogenesis was exacerbated if mouse skin was inflamed as a result of skin wounding or infection. Since hyaluronan (HA) catabolism is activated during skin injury and fibroblast-to-adipocyte differentiation is dependent on HA, we tested the hypothesis that HA fragments could alter colon fibroblast function by targeted expression of human hyaluronidase-1 in basal keratinocytes from mouse skin. Hyaluronidase expression in the skin activated intestinal stromal fibroblasts, altered the fecal microbiome, and promoted excessive reactive adipogenesis and increased inflammation in the colon after challenge with dextran sodium sulfate. The response to digested HA was dependent on expression of TLR4 by preadipocytes. Collectively, these results suggest that the association between skin inflammation and IBD may be due to recognition by mesenchymal fibroblasts in the colon of HA released during inflammation of the skin.

Pediatric nonalcoholic fatty liver disease and the microbiome: Mechanisms contributing to pathogenesis and progression.

Nonalcoholic fatty liver disease (NAFLD) is the most common form of pediatric liver disease in the United States, and often associated with obesity and metabolic syndrome. NAFLD comprises a broad spectrum of liver diseases, from hepatic steatosis to steatohepatitis, fibrosis and cirrhosis. Disease progression is considered a multi-modal process of liver injury. The intestinal microbiome has been implicated in several aspects of NAFLD pathophysiology. Pediatric studies associating the intestinal microbiome with NAFLD have been limited in number and complicated by inconsistencies in study design and approach. Nevertheless, they provide support for involvement of the intestinal microbiome in NAFLD development and progression and point to common mechanisms shared by microbiome-associated inflammatory diseases with potential to inform future therapeutic intervention.

Lactobacillus plantarum 299v probiotic supplementation in men with stable coronary artery disease suppresses systemic inflammation.

Recent trials demonstrate that systemic anti-inflammatory therapy reduces cardiovascular events in coronary artery disease (CAD) patients. We recently demonstrated Lactobacillus plantarum 299v (Lp299v) supplementation improved vascular endothelial function in men with stable CAD. Whether this favorable effect is in part due to anti-inflammatory action remains unknown. Testing this hypothesis, we exposed plasma obtained before and after Lp299v supplementation from these subjects to a healthy donor's PBMCs and measured differences in the PBMC transciptome, performed gene ontological analyses, and compared Lp299v-induced transcriptome changes with changes in vascular function. Daily alcohol users (DAUs) (n = 4) had a significantly different response to Lp299v and were separated from the main analyses. Non-DAUs- (n = 15) showed improved brachial flow-mediated dilation (FMD) and reduced circulating IL-8, IL-12, and leptin. 997 genes were significantly changed. I.I.com decreased (1.01 ± 0.74 vs. 0.22 ± 0.51; P < 0.0001), indicating strong anti-inflammatory effects. Pathway analyses revealed downregulation of IL-1ß, interferon-stimulated pathways, and toll-like receptor signaling, and an increase in regulator T-cell (Treg) activity. Reductions in GBP1, JAK2, and TRAIL expression correlated with improved FMD. In non-DAU men with stable CAD, post-Lp299v supplementation plasma induced anti-inflammatory transcriptome changes in human PBMCs that could benefit CAD patients. Future studies should delineate changes in circulating metabolites responsible for these effects.

Modelling the impact of plasma therapy and immunotherapy for recovery of COVID-19 infected individuals.

Since the first case of COVID-19 was detected in Wuhan, China in December 2019, COVID-19 has become a pandemic causing a global economic and public health emergency. There is no known treatment or vaccine available for COVID-19 during the initial period of the outbreak. Immunotherapy and plasma therapy has been used with satisfactory efficacy over the past two decades in many viral infections like SARS (Systemic Acute Respiratory Syndrome), MERS (Middle East Respiratory Syndrome) and H1N1. Limited data from China show clinical benefit, radiological resolution, reduction in viral loads and improved survival. We aim to create a mathematical model for COVID-19 transmission and then apply various control parameters to see their effects on recovery from COVID-19 disease. We have formulated a system of non-linear ordinary differential equations, calculated basic reproduction R0 and applied five different controls (self-isolation, quarantine, herd immunity, immunotherapy, plasma therapy) to test the effectiveness of plasma therapy. Control optimality was checked by Lagrangian functions. Numerical simulations and bifurcation analysis were carried out. The study concludes that the COVID-19 outbreak can be controlled up to a significant level in three weeks after applying all the control strategies together. These strategies lead to reduction in hospitalization and a rise in recovery from infection. Immunotherapy is highly effective initially in hospitalized infected individuals however better results were seen in the long term with plasma therapy.

Risks of Second Primary Gynecologic Cancers following Ovarian Cancer Treatment in Asian Ethnic Subgroups in the United States, 2000-2016.

BACKGROUND: The differential occurrence of second primary cancers by race following ovarian cancer is poorly understood. Our objective was to determine the incidence of second primary gynecologic cancers (SPGC) following definitive therapy for ovarian cancer. Specifically, we aimed to determine differences in SPGC incidence by Asian ethnic subgroups. METHODS: We identified 27,602 women ages 20 years and older and diagnosed with first primary epithelial ovarian cancer between 2000 and 2016 who received surgery and chemotherapy in 18 population-based Surveillance, Epidemiology and End Results Program registries. We compared the incidence of SPGC with expected incidence rates in the general population of women using estimated standardized incidence ratios (SIR) and 95% confidence intervals (CI). RESULTS: The incidence of SPGC was lower among White women (SIR = 0.73; 95% CI, 0.59-0.89), and higher among Black (SIR = 1.80; 95% CI, 0.96-3.08) and Asian/Pacific Islander (API) women (SIR = 1.83; 95% CI, 1.07-2.93). Increased risk of vaginal cancers was observed among all women, although risk estimates were highest among API women (SIR = 26.76; 95% CI, 5.52-78.2) and were also significant for risk of uterine cancers (SIR = 2.53; 95% CI, 1.35-4.33). Among API women, only Filipinas had significantly increased incidence of SPGC overall including both uterine and vaginal cancers. CONCLUSIONS: Risk of SPGC following treatment of ovarian cancer differs by race and ethnicity, with Filipina women having the highest rates of second gynecologic cancers among Asian women. IMPACT: Ensuring access and adherence to surveillance may mitigate ethnic differences in the early detection and incidence of second gynecologic cancers.

Modelling COVID-19 Transmission in the United States through Interstate and Foreign Travels and Evaluating Impact of Governmental Public Health Interventions

BackgroundThe first case of COVID-19 was reported in Wuhan, China in December 2019. The disease has spread to 210 countries and has been labelled as pandemic by WHO. Modelling, evaluating, and predicting the rate of disease transmission is crucial for epidemic prevention and control. Our aim is to assess the impact of interstate and foreign travel and public health interventions implemented by the United States government in response to the Covid-19 pandemic. MethodsA disjoint mutually exclusive compartmental model is developed to study transmission dynamics of the novel coronavirus. A system of non-linear differential equations was formulated and the basic reproduction number R0 was computed. Stability of the model was evaluated at the equilibrium points. Optimal controls were applied in the form of travel restrictions and quarantine. Numerical simulations were conducted. ResultsAnalysis shows that the model is locally asymptomatically stable, at endemic and foreigners free equilibrium points. Without any mitigation measures, infectivity and subsequent hospitalization of the population increases while placing interstates individuals and foreigners under quarantine, decreases the chances of exposure and subsequent infection, leading to an increase in the recovery rate. ConclusionInterstate and foreign travel restrictions, in addition to quarantine, help in effectively controlling the epidemic.

Modelling the impact of Plasma Therapy and Immunotherapy for Recovery of COVID-19 Infected Individuals

Since the first case of COVID-19 was detected in Wuhan, China in December 2019, COVID-19 has become a pandemic causing a global economic and public health emergency. There is no known treatment or vaccine available for COVID-19 to date. Immunotherapy and plasma therapy has been used with satisfactory efficacy over the past two decades in many viral infections like SARS (Systemic Acute Respiratory Syndrome), MERS (Middle East Respiratory Syndrome), and H1N1. Limited data from China show clinical benefit, radiological resolution, reduction in viral loads, and improved survival. Our aim is to create a mathematical model for COVID-19 transmission and then apply various control parameters to see their effects on recovery from COVID-19 disease. We have formulated a system of non-linear ordinary differential equations, calculated basic reproduction R0, and applied five different controls (self-isolation, quarantine, herd immunity, immunotherapy, plasma therapy) to test the effectiveness of control strategy. Control optimality was checked by Lagrangian functions. Numerical simulations and bifurcation analyses were carried out. The study concludes that the COVID-19 outbreak can be controlled up to a significant level three weeks after applying all the control strategies together. These strategies lead to a reduction in hospitalization and a rise in recovery from infection. Immunotherapy is highly effective initially in hospitalized infected individuals however better results were seen in the long term with plasma therapy.