Emerging and reemerging infectious diseases: global trends and new strategies for their prevention and control.

To adequately prepare for potential hazards caused by emerging and reemerging infectious diseases, the WHO has issued a list of high-priority pathogens that are likely to cause future outbreaks and for which research and development (R&D) efforts are dedicated, known as paramount R&D blueprints. Within R&D efforts, the goal is to obtain effective prophylactic and therapeutic approaches, which depends on a comprehensive knowledge of the etiology, epidemiology, and pathogenesis of these diseases. In this process, the accessibility of animal models is a priority bottleneck because it plays a key role in bridging the gap between in-depth understanding and control efforts for infectious diseases. Here, we reviewed preclinical animal models for high priority disease in terms of their ability to simulate human infections, including both natural susceptibility models, artificially engineered models, and surrogate models. In addition, we have thoroughly reviewed the current landscape of vaccines, antibodies, and small molecule drugs, particularly hopeful candidates in the advanced stages of these infectious diseases. More importantly, focusing on global trends and novel technologies, several aspects of the prevention and control of infectious disease were discussed in detail, including but not limited to gaps in currently available animal models and medical responses, better immune correlates of protection established in animal models and humans, further understanding of disease mechanisms, and the role of artificial intelligence in guiding or supplementing the development of animal models, vaccines, and drugs. Overall, this review described pioneering approaches and sophisticated techniques involved in the study of the epidemiology, pathogenesis, prevention, and clinical theatment of WHO high-priority pathogens and proposed potential directions. Technological advances in these aspects would consolidate the line of defense, thus ensuring a timely response to WHO high priority pathogens.

Preparing the developing world for the next pandemic: Evidence from China's R&D blueprint for emerging infectious diseases.

BACKGROUND: With double pressures of endemic and imported emerging infectious diseases (EIDs), China's ability to detect, prevent and control the unknown virus is of regional and global interest. This study aimed to establish an R&D Blueprint for EIDs in China by identifying the list of prioritized diseases and medical countermeasures (MCMs) that need proactive actions for the next pandemic. METHODS: The process mainly referred to the World Health Organization's prioritization methodology, supplemented by pipeline landscape, rapid risk assessment and multi-dimensional analysis. The study included five steps: 1) identifying potential pathogens, 2) screening into the long list, 3) prioritizing the long list, 4) identifying the final list and 5) generating an R&D Blueprint. RESULTS: China's R&D Blueprint identified 14 viral pathogens and two virus groups (i.e., Influenza HxNy and Coronavirus X) for proactive and representative MCM development. At least one diagnostic candidate in preclinical study, and one therapeutic and one vaccine candidate in Phase I/II clinical trials for each prioritized pathogen were suggested to be developed as strategic national stockpiles. Various generalized and innovative platform technologies were also highlighted for enhancing overall capacities of EID preparedness and response, covering basic research, experiment, detection, prevention and control, surveillance and information sharing. CONCLUSIONS: This is the first study in developing countries that established an R&D Blueprint of prioritized diseases, countermeasures and technologies. Our findings could help to drive pre-emptive scientific and technological actions toward emerging pathogens that may cause the next epidemic and could provide evidence-based strategies for developing countries to establish their national health research agenda tailored to health and research context under resource-limited settings.

Epidemiology and global spread of emerging tick-borne Alongshan virus.

The emergence and spread of novel viral pathogens is a major threat to human health, particularly in the context of climate and human-induced change in land use. Alongshan virus (ALSV) is a tick-borne virus associated with human disease, which was first identified in northeast China. More recently, several studies reported the emergence of ALSV in mammalian and arthropod hosts in multiple different countries outside of Asia, and the first viral genome sequencing data has become available. ALSV is a member of the Jingmenvirus group closely related to the Flaviviridae family. Unusually, the positive-sense, single-stranded RNA genome of ALSV is segmented and consists of four distinct segments, two of which show homology with the NS3 and NS5 protein encoding regions of non-segmented flaviviruses. Transmission of arthropod-borne pathogens will likely increase in the future due to environmental change mediated by a variety of environmental and ecological factors and increasing human encroachment into wild animal habitats. In this review, we present current knowledge of global ALSV distribution and emergence patterns, highlight genetic diversity, evolution and susceptible species. Finally, we discuss the role of this emerging tick-borne virus in the context of urbanization and global health.

Kinetics of Viral Shedding for Outbreak Surveillance of Emerging Infectious Diseases: Modeling Approach to SARS-CoV-2 Alpha and Omicron Infection.

BACKGROUND: Previous studies have highlighted the importance of viral shedding using cycle threshold (Ct) values obtained via reverse transcription polymerase chain reaction to understand the epidemic trajectories of SARS-CoV-2 infections. However, it is rare to elucidate the transition kinetics of Ct values from the asymptomatic or presymptomatic phase to the symptomatic phase before recovery using individual repeated Ct values. OBJECTIVE: This study proposes a novel Ct-enshrined compartment model to provide a series of quantitative measures for delineating the full trajectories of the dynamics of viral load from infection until recovery. METHODS: This Ct-enshrined compartment model was constructed by leveraging Ct-classified states within and between presymptomatic and symptomatic compartments before recovery or death among people with infections. A series of recovery indices were developed to assess the net kinetic movement of Ct-up toward and Ct-down off recovery. The model was applied to (1) a small-scale community-acquired Alpha variant outbreak under the "zero-COVID-19" policy without vaccines in May 2021 and (2) a large-scale community-acquired Omicron variant outbreak with high booster vaccination rates following the lifting of the "zero-COVID-19" policy in April 2022 in Taiwan. The model used Bayesian Markov chain Monte Carlo methods with the Metropolis-Hastings algorithm for parameter estimation. Sensitivity analyses were conducted by varying Ct cutoff values to assess the robustness of the model. RESULTS: The kinetic indicators revealed a marked difference in viral shedding dynamics between the Alpha and Omicron variants. The Alpha variant exhibited slower viral shedding and lower recovery rates, but the Omicron variant demonstrated swifter viral shedding and higher recovery rates. Specifically, the Alpha variant showed gradual Ct-up transitions and moderate recovery rates, yielding a presymptomatic recovery index slightly higher than 1 (1.10), whereas the Omicron variant had remarkable Ct-up transitions and significantly higher asymptomatic recovery rates, resulting in a presymptomatic recovery index much higher than 1 (152.5). Sensitivity analysis confirmed the robustness of the chosen Ct values of 18 and 25 across different recovery phases. Regarding the impact of vaccination, individuals without booster vaccination had a 19% higher presymptomatic incidence rate compared to those with booster vaccination. Breakthrough infections in boosted individuals initially showed similar Ct-up transition rates but higher rates in later stages compared to nonboosted individuals. Overall, booster vaccination improved recovery rates, particularly during the symptomatic phase, although recovery rates for persistent asymptomatic infection were similar regardless of vaccination status once the Ct level exceeded 25. CONCLUSIONS: The study provides new insights into dynamic Ct transitions, with the notable finding that Ct-up transitions toward recovery outpaced Ct-down and symptom-surfacing transitions during the presymptomatic phase. The Ct-up against Ct-down transition varies with variants and vaccination status. The proposed Ct-enshrined compartment model is useful for the surveillance of emerging infectious diseases in the future to prevent community-acquired outbreaks.

Emerging patterns in rodent-borne zoonotic diseases.

Rodents are ubiquitous and typically unwelcome dwellers in human habitats worldwide, infesting homes, farm fields, and agricultural stores and potentially shedding disease-causing microbes into the most human-occupied of spaces. Of the vertebrate animal taxa that share pathogens with us, rodents are the most abundant and diverse, with hundreds of species of confirmed zoonotic hosts, some of which have nearly global distributions. However, only 12% of rodent species are known to be sources of pathogens that also infect people, and those rodents that do are now recognized as tending to share a suite of predictable traits. Here, we characterize those traits and explore them in the context of three emerging or reemerging rodent-borne zoonotic diseases of people: Lassa fever, Lyme disease, and plague.

The Effect of Coronavirus Disease 2019 and Other Emerging Infections on Dentistry.

The appearance of coronavirus disease 2019 (COVID-19) and other emerging infections has significantly impacted the field of dentistry, leading to widespread changes in practices and protocols. This has included the implementation of strict infection control measures, such as meticulous use of personal protective equipment, minimizing aerosol-generating procedures, and the adoption of teledentistry to reduce in-person contact. To date, the complete impact of delays in dental care caused by lockdowns has yet to be determined. The challenges faced during the COVID-19 pandemic have propelled innovation, shaping a new era of dentistry focused on safety against novel and re-emerging infections.

Pythium insidiosum: an emerging pathogen that is easily misdiagnosed and given treatment as a fungus.

Background: Pythium insidiosum (P. insidiosum) is the causative agent of pythiosis, an infectious disease with a high morbidity and fatality rate. Pythiosis cases have increased dramatically during the past ten years, particularly in tropical and subtropical areas. Sadly, microbiologists and medical professionals know very little about pythiosis, and the disease is frequently challenging to identify. It is frequently misdiagnosed as a fungal infection. Methods: We report two cases of pythiosis, one was Pythium keratitis, the other was cutaneous pythiosis. The patient with corneal infection had no underlying disease, while the patient with cutaneous pythiosis had a history of liver cirrhosis, diabetes, and psoriasis. The corneal sample and subcutaneous pus were sent for metagenomic Next-Generation Sequencing (mNGS). To further diagnose the isolated strain, P. insidiosum zoospores were induced to produce by co-incubation with sterile grass leaves in sterile pond water. Their zoospores were used as an inoculum for drug susceptibility testing by disk diffusion and broth microdilution method. Results: The mNGS of two cases were reported as P. insidiosum. Zoospores were produced after incubation 48h. The zoospores were collected for drug susceptibility assay. All antifungal drugs, antibacterial drugs of ß-Lactams, vancomycin, levofloxacin, ciprofloxacin, gentamicin, trimethoprim-sulfamethoxazole, clindamycin have no inhibitory activity against P. insidiosum in vitro. Minocycline, tigecycline, linezolid, erythromycin and azithromycin have significant in vitro activity against P. insidiosum. Based on the susceptibility results, the drug was changed from itraconazole to linezolid and minocycline, along with multiple debridements and drainage for cutaneous pythiosis. The patient was discharged after 24 days of treatment. Conclusions: Early and accurate identification, combined with aggressive surgical debridement and appropriate drug therapy, can greatly improve patient managements. Conventional culture and zoospore induction remain gold standard for diagnosis; however, DNA-based method should be performed simultaneously. The drug susceptibility testing provides profound effects on proper drug selection against P. insidiosum.

Building Clinical Care Capacity for Patients With Special Pathogens in Advance of the Next Outbreak.

In response to the growing number of outbreaks of emerging infectious diseases, the US Administration for Strategic Preparedness and Response (ASPR) has embarked on a plan to improve and expand special pathogen patient care capabilities. To achieve this, ASPR is developing a coordinated network of Regional Emerging Special Pathogen Treatment Centers (RESPTCs) to serve as state-of-the-art facilities staffed by a highly trained workforce to care for and manage special pathogen patients across the lifespan. The RESPTC network represents the operational arm of a broader US National Special Pathogen System of care to prevent and prepare for the next infectious disease outbreak. RESPTCs are strategically located in every region across the country and form a network linking local and regional healthcare partners to enhance national preparedness through training in best practices for detection, isolation, and treatment of individuals suspected of or known to be infected with a special pathogen. This local, regional, and national network is also designed to lead a coordinated response that includes the dissemination of accurate and trustworthy information to responders and the public. The overarching goal of the RESPTCs is to serve as a valuable resource for clinical care, training, and material support to meet current and future major infectious diseases challenges. In this case study, 2 new RESPTCs, MedStar Washington Hospital Center and the University of North Carolina, describe their experiences related to designing a biocontainment unit, creating clinical teams, building staff resiliency, receiving mentoring from regional RESPTC partners, and developing opportunities for innovation.

The Role of High-Level Isolation Units in Response to High-Consequence and Emerging Infectious Diseases: Experience of the German STAKOB Network.

This case study describes the experience of the German Permanent Working Group of Competence and Treatment Centers for High Consequence Infectious Diseases, known as STAKOB (Ständiger Arbeitskreis der Kompetenz- und Behandlungszentren für Krankheiten durch hochpathogene Erreger). STAKOB brings together public health authorities (competence centers) and high-level isolation units (treatment centers) to collaborate on the clinical management of high-consequence infectious diseases (HCIDs) and emerging infectious diseases. The network is coordinated by the Robert Koch Institute, Germany's federal public health institute. The main tasks of STAKOB are to strengthen HCID clinical and public health management and increase expert knowledge on HCID and non-HCID emerging infectious diseases in Germany. STAKOB enables the exchange of knowledge and experiences; development of guidelines on infection prevention and control measures, clinical management, and therapy; and support for the World Health Organization and other outbreak responses internationally. The past years have shown how important the STAKOB network is for Germany-not only in providing critical care for HCID cases but also increasing capacity to support public health and clinical management of emerging infectious disease cases. However, maintaining several high-level isolation units in Germany requires a high commitment of financial, material, and human resources. Due to the rarity of HCID and emerging infectious disease events, maintaining the appropriate level of preparedness and ensuring sufficient investments is an ongoing struggle. Nevertheless, it is essential to have a network ready to react to HCID and non-HCID emerging infectious diseases in times of a changing biosecurity and infectious landscape.

Hyalomma marginatum - an emerging tickborne disease vector for the UK?

The tick Hyalomma marginatum is expanding its geographical range, reinforcing the need for surveillance and control to prevent the emergence of tickborne equine disease. Daniel Armstrong, policy adviser for exotic animal diseases at Defra, explains more.

What are the frequent complaints voiced by inpatients and physicians amidst the emerging infectious diseases? - An illustrative instance of the COVID-19.

INTRODUCTION: Emerging infectious diseases (EIDs) can disrupt the healthcare system, causing regulatory changes that affect the healthcare-seeking process and potentially increase patient-physician dissatisfaction. This study aimed to collect and analyze patients' and physicians' complaints during an EID outbreak to inform potential clues regarding medical quality and patient safety enhancement in future dealing with EIDs, employing text mining methodologies. METHODS: In this descriptive study, complaint records from January 2020 to February 2023 at West China Hospital, a national medical facility in China, were analyzed. Patient and physician complaints have been retrospectively retrieved from the record from the medical department, and then categorized into distinct groups based on reporting reasons, encompassing COVID-19-related policies, healthcare access, availability of medical resources, and financial concerns. RESULTS: During the COVID-19 pandemic, 541 COVID-19-related complaints were identified: 330 (61.00%) from patients and 211 (39.00%) from physicians. The monthly volume of complaints fluctuated, starting at 10 in 2020, peaking at 21 in 2022, and dropping to 14 in 2023. Most complaints from inpatients were expressed by older males aged 40 to 65 (38.82%, 210/541). The primary source of complaints was related to mandatory COVID-19 policies (79.30%, 429/541), followed by concerns regarding timely healthcare services (31.61%, 171/541). Few complaints were expressed regarding the insufficiency of medical resources (2.77%, 15/541) and the high costs (4.25%, 23/541). The frequency of complaints expressed by doctors and patients in the emergency department was higher compared with other departments (24.58%, 133/541). CONCLUSIONS: Increased complaints may serve as a primitive and timely resource for investigating the potential hazards and drawbacks associated with policies pertaining to EIDs. Prompt collection and systematical analysis of patient and physician feedback could help us accurately evaluate the efficacy and repercussions of these policies. Implementing complaints-based assessment might improve care standards in forthcoming healthcare environments grappling with EIDs.

Echinococcus ortleppi infection in humans: An emerging zoonosis in Asia.

Echinococcus ortleppi is the genotype G5 of Echinococcus granulosus sensu lato and is a zoonotic canine tapeworm of which larvae causes cystic diseases in domestic animals and also humans. While this species is highly endemic and widely spread in domestic animals, human infection is extremely rare and only sporadic, and thus, entire picture of human cystic echinococcosis due to infection with E. ortleppi is unclear. We have made an extensive literature review on the cases of E. ortleppi infection in humans and found a total of 19 cases from various places in the world with recent emergence in Asian countries.

Polio, public health memories and temporal dissonance of re-emerging infectious diseases in the global north.

Social science research on polio has been centred in the global south, where countries that remain endemic or vulnerable to outbreaks are located. However, closely-related strains of poliovirus were detected in the sewage systems of several New York State counties and London boroughs in 2022. These detections constituted the first encounters with polio in the United States and United Kingdom for a generation - for both public health agencies and publics alike. This paper takes the transnational spread of poliovirus in 2022 as an opportunity to critique how public health memories of twentieth-century polio epidemics were mobilised to encourage vaccine uptake among groups considered vulnerable to transmission, notably Orthodox Jewish families. The study integrates data collected in London and New York as part of academic engagement with health protection responses to the spread of polio. Methods in both settings involved ethnographic research, and a total of 59 in-depth semi-structured interviews with public health professionals, healthcare providers, and Orthodox Jewish community partners and residents. Analysis of results demonstrate that narratives of epidemiological progress were deployed in public health responses in London and New York, often through references to sugar cubes, iron lungs, and timelines that narrate the impact of routine childhood immunisations. While memories of polio were deployed in both settings to provoke an urgency to vaccinate, vulnerable publics instead considered the more recent legacy of the COVID-19 pandemic when deciding whether to trust recommendations and responses. Critical attention to memory places analysis on the divergences between institutional (public health agencies) and peopled (publics) responses to disease events. Responses to re-emerging infectious disease outbreaks engender a temporal dissonance when historical narratives are evoked in ways that contrast with the contemporary dilemmas of people and parents.