Mannose-binding lectin-associated serine protease 2(MASP-2) is a member of serine protease family and plays a crucial role in activating the complement lectin pathway. When mannose residues on the surface of a pathogen are recognized by mannose-binding lectins (MBL) or fibrinogen collagen (FCN), MASP-2 is activated. This activation then triggers the cleavage of C4 and C2 to form C3 convertase, thereby initiating the lectin pathway of the complement system. Numerous studies have demonstrated that MASP-2 gene polymorphisms and serum levels are closely related with various diseases, including tumors, infectious diseases, autoimmune diseases and so on. In this review, we summarize the relationships between MASP-2 and tumors, infectious diseases, autoimmune diseases. We aim to provide a theoretical basis for the early diagnosis, prognosis evaluation and clinical treatment of various diseases.
Humans ; Mannose-Binding Protein-Associated Serine Proteases/metabolism* ; Neoplasms/metabolism* ; Autoimmune Diseases/genetics* ; Animals ; Polymorphism, Genetic ; Communicable Diseases/genetics*

OBJECTIVES: To investigate the epidemiological characteristics and changing trends of communicable diseases among children and adolescents in China from 1990 to 2021. METHODS: Based on the Global Burden of Disease Database, epidemiological indicators for communicable diseases among the population aged under 20 years in China from 1990 to 2021 were selected to analyze the burden of communicable diseases in this population, and a comparative analysis was performed with global data as well as data from Western Europe and North America. RESULTS: In 1990-2021, the overall burden of communicable diseases tended to decrease among children and adolescents in China. In 2021, the prevalence rate of communicable diseases in China was lower than the global prevalence rate and was higher than that in Western Europe and North America. There was a significant reduction in the mortality rate of communicable diseases, and the gap with Western Europe and North America gradually narrowed year by year. The overall incidence rate, mortality rate, and disability-adjusted life year rate of communicable diseases in males were higher than those in females, and respiratory infections and intestinal infections were more common in children aged <5 years, while the incidence rate of sexually transmitted diseases was higher in adolescents. CONCLUSIONS From 1990 to 2021, the disease burden of communicable diseases among the population under 20 years old in China has significantly decreased. However, there is still a certain gap compared to developed regions. Strengthening the prevention and control of diseases such as respiratory infections and acquired immunodeficiency syndrome, as well as enhancing health interventions for children under 5 years old, will help improve the overall health level of children and adolescents in China.
Humans ; Adolescent ; Communicable Diseases/mortality* ; Child ; China/epidemiology* ; Male ; Female ; Child, Preschool ; Infant ; Young Adult ; Cost of Illness ; Infant, Newborn

Climate and weather significantly influence the duration, timing, and intensity of disease outbreaks, reshaping the global landscape of infectious diseases. Rising temperatures and shifts in precipitation patterns driven by climate change can directly impact the survival and reproduction of pathogens and vector organisms. Moreover, climate change is expected to exacerbate extreme weather events, including floods and droughts, which can disrupt infrastructure and increase the risk of water- and foodborne diseases. There are potential shifts in the temporal and spatial patterns of infectious disease transmission owing to climate change. Furthermore, climate change may alter the epidemiology of vaccine-preventable diseases. These climatic variations not only affect the ecological characteristics of pathogens and vectors but also indirectly influence human behaviors and socioeconomic conditions, further amplifying disease transmission risks. Addressing this challenge requires an interdisciplinary collaboration and comprehensive public health strategies. This review aims to synthesize the current evidence on the impact of climate change on climate-sensitive infectious diseases and elucidate the underlying mechanisms and transmission pathways. Additionally, we explored adaptive policy strategies to mitigate the public health burden of infectious diseases in the context of climate change, offering insights for global health governance and disease control efforts.
Climate Change ; Communicable Diseases/transmission* ; Humans ; Animals ; Global Health

The COVID-19 pandemic highlighted critical gaps in the Philippine health laboratory system, including limited testing capacities, insufficient trained personnel, and inadequate resource distribution. To address these issues, the Philippine government established the Office for Health Laboratories (OHL) and sought technical assistance from the Japan International Cooperation Agency (JICA) through the Project for Strengthening the Philippine National Health Laboratory Network for Infectious Diseases (PHeLNIDs). This project aims to enhance the National Health Laboratory Network's (NHLN) capacity for infectious disease surveillance and response. Phase 1 of the PHeLNIDs project included focus group discussions (FGDs) conducted across 17 regions to assess challenges and develop recommendations for a tier-based laboratory network. Key findings revealed logistical, workforce, transportation, and data management challenges that hinder the effectiveness of specimen referral workflows. Recommendations emphasized decentralizing diagnostic capabilities through subnational reference laboratories, strengthening logistics, and implementing an Integrated Laboratory Information Management System (ILIMS). This article underscores the importance of laboratory decentralization, capacity building, and improved resource management to enhance laboratory-based surveillance and response to emerging infectious diseases. The proposed interventions aim to bolster the Philippine laboratory network, reduce turnaround times, and improve public health outcomes.

Hansen’s disease remains a critical health issue in tropical countries like the Philippines. Delayed diagnosis, especially in the context of indiscriminate corticosteroid use, can lead to severe complications. This case highlights the importance of proper referral, ruling out infections, and cautious steroid use.

A 29-year-old Filipino male presented with a 4-year history of erythematous, scaly plaques on his face and scalp, for which he had not sought treatment. One year later, the plaques spread to his trunk, accompanied by arthralgia. Misdiagnosed with psoriasis, he self-medicated with clobetasol and dexamethasone for three years. Over time, he developed signs of Cushing syndrome. Two months before consultation, after a fall, he experienced lower extremity weakness, hypoesthetic plaques on his legs, and blurred vision, but continued using steroids. Upon admission, he was diagnosed with iatrogenic Cushing syndrome. Steroid tapering reduced generalized edema, revealing nodules on his ears and extremities. Slit-skin smear and histopathology confirmed Hansen’s disease. Unfortunately, he succumbed to septic shock before completing treatment.

Misdiagnosis and prolonged steroid use pose risks by masking infections like leprosy. In regions where infectious diseases are prevalent, clinicians should exercise caution before prescribing steroids, as overuse can lead to “therapeutic incognito,” complicating diagnosis. Early referral to dermatologists for undiagnosed or refractory skin lesions is critical in preventing complications. This case emphasizes the importance of educating healthcare providers on judicious steroid use and ruling out infections. Delayed diagnosis of leprosy, as demonstrated here, can lead to severe outcomes, reinforcing the need for timely intervention and thorough patient evaluation.

The rise in global life expectancy has led to an increase in the older population, presenting significant challenges in managing infectious diseases. Aging affects the innate and adaptive immune systems, resulting in chronic low-grade inflammation (inflammaging) and immune function decline (immunosenescence). These changes would impair defense mechanisms, increase susceptibility to infections and reduce vaccine efficacy in older adults. Cellular senescence exacerbates these issues by releasing pro-inflammatory factors, further perpetuating chronic inflammation. Moreover, comorbidities, such as cardiovascular disease and diabetes, which are common in older adults, amplify immune dysfunction, while immunosuppressive medications further complicate responses to infections. This review explores the molecular and cellular mechanisms driving inflammaging and immunosenescence, focusing on genomic instability, telomere attrition, and mitochondrial dysfunction. Additionally, we discussed how aging-associated immune alterations influence responses to bacterial, viral, and parasitic infections and evaluated emerging antiaging strategies, aimed at mitigating these effects to improve health outcomes in the aging population.
Humans ; Aging/physiology* ; Communicable Diseases/immunology* ; Immunosenescence/physiology* ; Inflammation/immunology* ; Genomic Instability

The Qa-1 in mice is homologous to human leukocyte antigen E(HLA-E), and both of them belong to the non-classical major histocompatibility complex I b(MHC-I b) molecules. Qa-1 is capable of presenting self or exogenous antigen peptides to interact with two distinct receptors, namely T cell receptor (TCR) and natural killer cell group 2 member A (or C) (NKG2A/C), thus playing an important role in immune response and regulation. Qa-1-restricted regulatory CD8⁺ T cell (CD8⁺ Treg) is one of the most studied CD8⁺ Treg subgroups, which can maintain immune homeostasis and autoimmune tolerance by exerting immunosuppressive effects. Consequently, Qa-1-restricted CD8⁺Treg cells are closely associated with the occurrence and development of various clinical diseases, such as tumors, infections, autoimmune diseases, and transplant rejections. This paper provides a comprehensive review of the phenotypic characteristics, functional effects, regulatory mechanisms of Qa-1-restricted CD8⁺ Treg cells, as well as the latest research progresses of Qa-1-restricted CD8⁺ Treg cells involved in the pathogenesis of infectious diseases.
Humans ; Animals ; T-Lymphocytes, Regulatory/immunology* ; Histocompatibility Antigens Class I/immunology* ; CD8-Positive T-Lymphocytes/immunology* ; Communicable Diseases/immunology*

Objective: To study the incubation period of the infection with 2019-nCoV Omicron variant BA.5.1.3. Methods: Based on the epidemiological survey data of 315 COVID-19 cases and the characteristics of interval censored data structure, log-normal distribution and Gamma distribution were used to estimate the incubation. Bayes estimation was performed for the parameters of each distribution function using discrete time Markov chain Monte Carlo algorithm. Results: The mean age of the 315 COVID-19 cases was (42.01±16.54) years, and men accounted for 30.16%. A total of 156 cases with mean age of (41.65±16.32) years reported the times when symptoms occurred. The log-normal distribution and Gamma distribution indicated that the M (Q₁, Q₃) of the incubation period from exposure to symptom onset was 2.53 (1.86, 3.44) days and 2.64 (1.91, 3.52) days, respectively, and the M (Q₁, Q₃) of the incubation period from exposure to the first positive nucleic acid detection was 2.45 (1.76, 3.40) days and 2.57 (1.81, 3.52) days, respectively. Conclusions: The incubation period by Bayes estimation based on log-normal distribution and Gamma distribution, respectively, was similar to each other, and the best distribution of incubation period was Gamma distribution, the difference between the incubation period from exposure to the first positive nucleic acid detection and the incubation period from exposure to symptom onset was small. The median of incubation period of infection caused by Omicron variant BA.5.1.3 was shorter than those of previous Omicron variants.
Male ; Humans ; Adult ; Middle Aged ; SARS-CoV-2 ; COVID-19 ; Bayes Theorem ; Infectious Disease Incubation Period ; Nucleic Acids

OBJECTIVES: To study the effect of breastfeeding on immune function in infants with human cytomegalovirus (HCMV) infection. METHODS: A retrospective analysis was performed on the medical data of 135 infants with HCMV infection who were admitted to Children's Hospital Affiliated to Zhengzhou University from January 2021 to May 2022, and all these infants received breastfeeding. According to the results of breast milk HCMV-DNA testing, the infants were divided into two groups: breast milk HCMV positive (n=78) and breast milk HCMV negative (n=57). According to the median breast milk HCMV-DNA load, the infants in the breast milk HCMV positive group were further divided into two subgroups: high viral load and low viral load (n=39 each). Related indicators were compared between the breast milk positive and negative HCMV groups and between the breast milk high viral load and low viral load subgroups, including the percentages of peripheral blood lymphocyte subsets (CD3⁺ T cells, CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, and CD19⁺ B cells), CD4⁺/CD8⁺ ratio, IgG, IgM, IgA, and urine HCMV-DNA load. RESULTS: There were no significant differences in the percentages of CD3⁺ T cells, CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, and CD19⁺ B cells, CD4⁺/CD8⁺ ratio, IgG, IgM, IgA, and urine HCMV-DNA load between the breast milk HCMV positive and HCMV negative groups, as well as between the breast milk high viral load and low viral load subgroups (P>0.05). CONCLUSIONS Breastfeeding with HCMV does not affect the immune function of infants with HCMV infection.
Female ; Child ; Humans ; Infant ; Breast Feeding ; Cytomegalovirus Infections ; CD8-Positive T-Lymphocytes ; Retrospective Studies ; Infectious Disease Transmission, Vertical ; Milk, Human ; Cytomegalovirus ; Immunity ; Immunoglobulin A ; Immunoglobulin G ; Immunoglobulin M

Alternative splicing (AS) is an evolutionarily conserved mechanism that removes introns and ligates exons to generate mature messenger RNAs (mRNAs), extremely improving the richness of transcriptome and proteome. Both mammal hosts and pathogens require AS to maintain their life activities, and inherent physiological heterogeneity between mammals and pathogens makes them adopt different ways to perform AS. Mammals and fungi conduct a two-step transesterification reaction by spliceosomes to splice each individual mRNA (named cis -splicing). Parasites also use spliceosomes to splice, but this splicing can occur among different mRNAs (named trans -splicing). Bacteria and viruses directly hijack the host's splicing machinery to accomplish this process. Infection-related changes are reflected in the spliceosome behaviors and the characteristics of various splicing regulators (abundance, modification, distribution, movement speed, and conformation), which further radiate to alterations in the global splicing profiles. Genes with splicing changes are enriched in immune-, growth-, or metabolism-related pathways, highlighting approaches through which hosts crosstalk with pathogens. Based on these infection-specific regulators or AS events, several targeted agents have been developed to fight against pathogens. Here, we summarized recent findings in the field of infection-related splicing, including splicing mechanisms of pathogens and hosts, splicing regulation and aberrant AS events, as well as emerging targeted drugs. We aimed to systemically decode host-pathogen interactions from a perspective of splicing. We further discussed the current strategies of drug development, detection methods, analysis algorithms, and database construction, facilitating the annotation of infection-related splicing and the integration of AS with disease phenotype.
Animals ; Alternative Splicing/genetics* ; RNA Splicing ; Spliceosomes/metabolism* ; RNA, Messenger/metabolism* ; Communicable Diseases/genetics* ; Mammals/metabolism*