Total Number Of New Infections Research Articles

Genotypic analysis of RTS,S/AS01E malaria vaccine efficacy against parasite infection as a function of dosage regimen and baseline malaria infection status in children aged 5–17 months in Ghana and Kenya: a longitudinal phase 2b randomised controlled trial

The first licensed malaria vaccine, RTS,S/AS01E, confers moderate protection against symptomatic disease. Because many malaria infections are asymptomatic, we conducted a large-scale longitudinal parasite genotyping study of samples from a clinical trial exploring how vaccine dosing regimen affects vaccine efficacy. Between Sept 28, 2017, and Sept 25, 2018, 1500 children aged 5-17 months were randomly assigned (1:1:1:1:1) to receive four different RTS,S/AS01E regimens or a rabies control vaccine in a phase 2b open-label clinical trial in Ghana and Kenya. Participants in the four RTS,S groups received two full doses at month 0 and month 1 and either full doses at month 2 and month 20 (group R012-20); full doses at month 2, month 14, month 26, and month 38 (group R012-14); fractional doses at month 2, month 14, month 26, and month 38 (group Fx012-14; early fourth dose); or fractional doses at month 7, month 20, and month 32 (group Fx017-20; delayed third dose). We evaluated the time to the first new genotypically detected infection and the total number of new infections during two follow-up periods (12 months and 20 months) in more than 36 000 dried blood spot specimens from 1500 participants. To study vaccine effects on time to the first new infection, we defined vaccine efficacy as one minus the hazard ratio (HR; RTS,S vs control) of the first new infection. We performed a post-hoc analysis of vaccine efficacy based on malaria infection status at first vaccination and force of infection by month 2. This trial (MAL-095) is registered with ClinicalTrials.gov, NCT03281291. We observed significant and similar vaccine efficacy (25-43%; 95% CI union 9-53) against first new infection for all four RTS,S/AS01E regimens across both follow-up periods (12 months and 20 months). Each RTS,S/AS01E regimen significantly reduced the mean number of new infections in the 20-month follow-up period by 1·1-1·6 infections (95% CI union 0·6-2·1). Vaccine efficacy against first new infection was significantly higher in participants who were infected with malaria (68%; 95% CI 50-80) than in those who were uninfected (37%; 23-48) at the first vaccination (p=0·0053). All tested dosing regimens blocked some infections to a similar degree. Improved vaccine efficacy in participants infected during vaccination could suggest new strategies for highly efficacious malaria vaccine development and implementation. GlaxoSmithKline Biologicals SA, PATH, Bill & Melinda Gates Foundation, and the German Federal Ministry of Education and Research.

Dynamic Changes in Disney Stock Price under Normalized Covid-19 Pandemic

Since the COVID-19 pandemic explosion in January 2020, the progress of numerous companies has been affected and, naturally, stocks have seen a correction as a result. In this article, the overall impact of the COVID-19 pandemic' will be analyzed under assessing the impact on Disney stock. In order to analyze the change in variation between the COVID-19 pandemic and the fluctuation in the price of Disney stock, the initial intercept was between the closing price of Disney stock and the total number of new infections recorded at the beginning of the COVID-19 pandemic breakout. These data were used to calculate the daily number of new infections and the return on Disney stock. The data were first tested for stationarity using the ADF Test and then a VAR model and an ARMA-GARCH model were developed for these data. This study showed that the effect of COVID-19 on Disney stock was not significant. At the end of the article, two types of investor psychology are analyzed and some references are given to investors.

The epidemiological situation of morbidity and mortality on HIV / AIDS cases in Poland and globally in recent years

Aim: The aim of this review is to summarize the data on the morbidity and mortality of HIV / AIDS in the years 2000-2020 in Poland and in the world. As a result of continuous insufficient diagnostics, still millions of people are not aware of the disease, which often results in regions or countries with a significantly increased incidence. We were looking for information about the impact of the current COVID-19 pandemic on the production, distribution, and prices. Availability of drugs, especially in middle and low income countries, was also examined.Materials and methods: PubMed databases and statistics from the National Institute of Public Health (NIZP- PZH) and global data from the websites of WHO, UNAIDS - Global HIV & AIDS statistics and HIV.gov were searched in June and July 2020. The UNAIDS 90-90-90 program was also assessed. This programme was run until 2020. In the PubMed database, we used medical terms "hiv", "aids", "hiv / aids". No language restrictions were added.Conclusion:UNAIDS report on the global AIDS epidemic shows that 2020 targets will not be met because of deeply unequal success; COVID-19 risks blowing HIV progress way off course. Missed targets have resulted in 3.5 million more HIV infections and 820 000 more AIDS-related deaths since 2015 than if the world was on track to meet the 2020 targets. In addition, the response could be set back further, by 10 years or more, if the COVID-19 pandemic results in severe disruptions to HIV services. Currently, the world is plunged into the fight against COVID-19 and people are forgetting that the HIV pandemic also carries a large number of deaths. Nevertheless, the spread of both viruses is different and in developed countries the possibility of significant spread of HIV is much lower than in poor countries. The spread of Sars-Cov2 virus is much more difficult to control. Although the risk of serious illness from COVID-19 for people with HIV is not known, people with HIV may have concerns and questions related to their risk. COVID-19 pandemic has seriously impacted the AIDS response and could disrupt it more. Progress in prevention of HIV transmission remains too slow and the estimated total number of new infections in 2019 is more than three times higher than the UNAIDS 2020 target. Despite advances in the scientific understanding of HIV and its prevention and treatment, and many years of significant efforts by the global health community and governmental and community organizations, too many HIV-positive people still lack access to prevention, care and treatment. There is still no cure for everybody with HIV / AIDS. Moreover, the HIV epidemic not only affects human health, but also strikes households, communities, and the development and economic growth of nations.

The impact of COVID-19 on transport volume and freight capacity dynamics: An empirical analysis in German food retail logistics

Governmental restrictions aspiring to slow down the spread of epidemic and pandemic outbreaks lead to impairments for economic operations, which impact transportation networks comprising the maritime, rail, air, and trucking industries. Witnessing a substantial increase in the number of infections in Germany, the authorities have imposed drastic restrictions on everyday life. Resulting panic buying and increasing home consumption had versatile impacts on transport volume and freight capacity dynamics in German food retail logistics. Due to the lack of prior research on the effects of COVID-19 on transport volume in retail logistics, as well as resulting implications, this article aspires to shed light on the phenomenon of changing volume and capacity dynamics in road haulage. After analyzing the transport volume of n = 15,715 routes in the timeframe of 23.03.2020 to 30.04.2020, a transport volume growth rate expressing the difference of real and expected transport volume was calculated. This ratio was then examined concerning the number of COVID-19 infections per day. The results of this study prove that the increasing freight volume for dry products in retail logistics does not depend on the duration of the COVID-19 epidemy but on the strength quantified through the total number of new infections per day. This causes a conflict of interest between transportation companies and food retail logistics for non-cooled transport capacity. The contributions of this paper are highly relevant to assess the impact of a possibly occurring second COVID-19 virus infection wave.

Optimal Control of Aquatic Diseases: A Case Study of Yemen’s Cholera Outbreak

We propose a mathematical model for the transmission dynamics of some strains of the bacterium Vibrio cholerae, responsible for the cholera disease in humans. We prove that, when the basic reproduction number is equal to one, a transcritical bifurcation occurs for which the endemic equilibrium emanates from the disease-free point. A control function is introduced into the model, representing the distribution of chlorine water tablets for water purification. An optimal control problem is then proposed and analyzed, where the goal is to determine the fraction of susceptible individuals who should have access to chlorine water tablets in order to minimize the total number of new infections plus the total cost associated with the distribution of chlorine water tablets, over the considered period of time. Finally, we consider real data of the cholera outbreak in Yemen, from 27 April 2017 to 15 April 2018, choosing the values of the parameters of the uncontrolled model that fit the real data. Using our optimal control results, we show, numerically, that the distribution of chlorine water tablets could have stopped, in a fast way, the worst cholera outbreak that ever occurred in human history. Due to the critical situation of Yemen, we also simulate the case where only a small percentage of susceptible individuals has access to chlorine water tablets and obtain an optimal control solution that decreases, substantially, the maximum number of infective individuals attained at the outbreak.

HIV Modes of Transmission in Sudan in 2014.

Background: In Sudan, where studies on HIV dynamics are few, model projections provide an additional source of information for policy-makers to identify data collection priorities and develop prevention programs. In this study, we aimed to estimate the distribution of new HIV infections by mode of exposure and to identify populations who are disproportionately contributing to the total number of new infections in Sudan. Methods: We applied the modes of transmission (MoT) mathematical model in Sudan to estimate the distribution of new HIV infections among the 15-49 age group for 2014, based on the main routes of exposure to HIV. Data for the MoT model were collected through a systematic review of peer-reviewed articles, grey literature, interviews with key participants and focus groups. We used the MoT uncertainty module to represent uncertainty in model projections and created one general model for the whole nation and 5 sub-models for each region (Northern, Central, Eastern, Kurdufan, and Khartoum regions). We also examined how different service coverages could change HIV incidence rates and distributions in Sudan.Results: The model estimated that about 6000 new HIV infections occurred in Sudan in 2014 (95% CI: 4651-7432). Men who had sex with men (MSM) (30.52%), female sex workers (FSW) (16.37%), and FSW’s clients accounted (19.43%) for most of the new HIV cases. FSW accounted for the highest incidence rate in the Central, Kurdufan, and Khartoum regions; and FSW’s clients had the highest incidence rate in the Eastern and Northern regions. The annual incidence rate of HIV in the total adult population was estimated at 330 per 1 000 000 populations. The incidence rate was at its highest in the Eastern region (980 annual infections per 1 000 000 populations).Conclusion: Although the national HIV incidence rate estimate was relatively low compared to that observed in some sub-Saharan African countries with generalized epidemics, a more severe epidemic existed within certain regions and key populations. HIV burden was mostly concentrated among MSM, FSW, and FSW’s clients both nationally and regionally. Thus, the authorities should pay more attention to key populations and Eastern and Northern regions when developing prevention programs. The findings of this study can improve HIV prevention programs in Sudan.

Prevention effectiveness of the "Internet Plus-based AIDS Comprehensive Prevention Service System" among MSM in Guangzhou: a dynamic model of infectious disease

Objective: To evaluate the effect of the "Interner Plus-based AIDS Comprehensive Prevention Service System" among MSM in Guangzhou, during 2010-2017, using a dynamic compartmental model. Methods: A dynamic compartmental model was developed to describe the HIV situation among MSM in Guangzhou. This model was parameterized on data from published literature or surveillance programs from the Guangzhou CDC. The Matlab 7.0 software was used for coding and analysis on collected data. HIV prevalence was analyzed among MSM under the status quo data and estimated the impact by the "Internet Plus" AIDS prevention services project. Results: HIV prevalence would have increased to 22.75% in 2017, and the total number of new HIV infections would have been 11 038, from 2010 to 2017, using the data status quo. Under the Guangzhou "Internet Plus" AIDS prevention services project, the prevalence of HIV among MSM from 2010 to 2017 was estimated to be 8.44%, 9.68%, 10.65%, 11.34%, 11.73%, 11.83%, 11.71% and 11.43% in Guangzhou, which were similar to the surveillance data. The total number of new infections in the past 8 years under the "Internet Plus" scenario was estimated to be 4 009. The "Internet Plus" program would have prevented 7 029 (63.68%) new infections during 2010-2017 as compared to the number, status quo. Conclusions: The fitting result of dynamic compartmental model seemed more reasonable, which was applicable to predict HIV epidemic among MSM in Guangzhou, suggesting that the increase of HIV prevalence had been curbed since the "Internet Plus" project which was launched in 2010, and the "Interner Plus-based AIDS Comprehensive Prevention Service System" had achieved the purpose as planned, epidemiologically.

Increased Susceptibility to Plasmodium falciparum in Infants is associated with Low, not High, Placental Malaria Parasitemia

Risk of malaria in infants can be influenced by prenatal factors. In this study, the potential for placental parasitemia at delivery in predicting susceptibility of infants to Plasmodium falciparum (Pf) infections was evaluated. Seventy-two newborns of mothers who were placental malaria negative (PM−) and of mothers who were PM+ with below (PM+ Lo) and above (PM + Hi) median placental parasitemia, were actively monitored during their first year of life. Median time to first PCR-detected Pf infection was shorter in PM + Lo infants (2.8 months) than in both PM− infants (4.0 months, p = 0.002) and PM + Hi infants (4.1 months, p = 0.01). Total number of new infections was also highest in the PM + Lo group. Only 24% of infants experienced clinical malaria episodes but these episodes occurred earlier in PM + Lo infants than in PM + Hi infants (p = 0.05). The adjusted hazard ratio (95% CI) of having Pf infection was 3.9 (1.8–8.4) and 1.5 (0.7–3.4) for infants in the PM + Lo and PM + Hi groups, respectively. Collectively, low placental parasitemia was associated with increased susceptibility to malaria during infancy. Therefore, malaria in pregnancy preventive regimens, such as sulfadoxine-pyremethamine, that reduce but do not eliminate placental Pf in areas of drug resistance may increase the risk of malaria in infants.

New method for estimating HIV incidence and time from infection to diagnosis using HIV surveillance data

To estimate HIV incidence and time between HIV infection and diagnosis of infection. We devised a new model for estimating the incidence of HIV infection and the time between infection and diagnosis from HIV surveillance data. Our approach takes into account temporal changes in HIV test-seeking behaviors and requires few data on individuals newly diagnosed with HIV (i.e. date of diagnosis and clinical status at diagnosis). Using our new approach, we analyzed data for patients newly diagnosed with HIV in France between April 2003 and December 2008. The estimated mean time between infection and diagnosis ranged from 37.0 months among men who have sex with men to approximately 53.0 months among heterosexual men. Intermediate values were obtained for injecting drug users and heterosexual women. We estimated that mean times changed very slightly (≤1.2 months) during the period 2004-2007: it shortened among MSM, remained stable among non-French-national heterosexual men, and lengthened in all the other exposure categories. We estimated that the total number of new infections increased, but not significantly, between 2004 and 2007, reaching 7851 [95% confidence interval 5400-9919] in 2007. MSM accounted for the largest number of new infections (38%). HIV continues to spread in France, and the average time between infection and HIV diagnosis remains excessively long. New policies to expand the offer and acceptance of voluntary HIV testing are thus urgently needed. Our method will also be very useful to monitor and evaluate the impact of future HIV testing policies.

Modelling geographic variation in the cost-effectiveness of control policies for infectious vector diseases: The example of Chagas disease

Few cost-effectiveness analysis (CEA) models have accounted for geographic variation in input parameters. This paper describes a deterministic discrete-time multi-state model to estimate the cost-effectiveness of vector control policies for Chagas disease, where implementation varies according to village characteristics. The model outputs include the total number of new infections, disability adjusted life years (DALYs) incurred, costs of associated healthcare, and total costs of the Ministry of Health's control policy for house surveillance and spraying. Incremental net benefits were estimated to determine Colombian villages in which it is cost-effective to implement the control policy. The robustness of these conclusions was evaluated by deterministic sensitivity analyses. The model should help provide a decision-support system to compare control policies and to allocate resources geographically.

Integrating HIV Prevention and Treatment: From Slogans to Impact

Background Through major efforts to reduce costs and expand access to antiretroviral therapy worldwide, widespread delivery of effective treatment to people living with HIV/AIDS is now conceivable even in severely resource-constrained settings. However, the potential epidemiologic impact of treatment in the context of a broader strategy for HIV/AIDS control has not yet been examined. In this paper, we quantify the opportunities and potential risks of large-scale treatment roll-out. Methods and Findings We used an epidemiologic model of HIV/AIDS, calibrated to sub-Saharan Africa, to investigate a range of possible positive and negative health outcomes under alternative scenarios that reflect varying implementation of prevention and treatment. In baseline projections, reflecting “business as usual,” the numbers of new infections and AIDS deaths are expected to continue rising. In two scenarios representing treatment-centered strategies, with different assumptions about the impact of treatment on transmissibility and behavior, the change in the total number of new infections through 2020 ranges from a 10% increase to a 6% reduction, while the number of AIDS deaths through 2020 declines by 9% to 13%. A prevention-centered strategy provides greater reductions in incidence (36%) and mortality reductions similar to those of the treatment-centered scenarios by 2020, but more modest mortality benefits over the next 5 to 10 years. If treatment enhances prevention in a combined response, the expected benefits are substantial—29 million averted infections (55%) and 10 million averted deaths (27%) through the year 2020. However, if a narrow focus on treatment scale-up leads to reduced effectiveness of prevention efforts, the benefits of a combined response are considerably smaller—9 million averted infections (17%) and 6 million averted deaths (16%). Combining treatment with effective prevention efforts could reduce the resource needs for treatment dramatically in the long term. In the various scenarios the numbers of people being treated in 2020 ranges from 9.2 million in a treatment-only scenario with mixed effects, to 4.2 million in a combined response scenario with positive treatment–prevention synergies. Conclusions These analyses demonstrate the importance of integrating expanded care activities with prevention activities if there are to be long-term reductions in the number of new HIV infections and significant declines in AIDS mortality. Treatment can enable more effective prevention, and prevention makes treatment affordable. Sustained progress in the global fight against HIV/AIDS will be attained only through a comprehensive response.