ABSTRACT
BACKGROUND: Global connectivity and environmental change pose continuous threats to dengue invasions from worldwide to China. However, the intrinsic relationship on introduction and outbreak risks of dengue driven by the landscape features are still unknown. This study aimed to map the patterns on source-sink relation of dengue cases and assess the driving forces for dengue invasions in China. METHODS: We identified the local and imported cases (2006-2020) and assembled the datasets on environmental conditions. The vector auto-regression model was applied to detect the cross-relations of source-sink patterns. We selected the major environmental drivers via the Boruta algorithm to assess the driving forces in dengue outbreak dynamics by applying generalized additive models. We reconstructed the internal connections among imported cases, local cases, and external environmental drivers using the structural equation modeling. RESULTS: From 2006 to 2020, 81,652 local dengue cases and 12,701 imported dengue cases in China were reported. The hotspots of dengue introductions and outbreaks were in southeast and southwest China, originating from South and Southeast Asia. Oversea-imported dengue cases, as the Granger-cause, were the initial driver of the dengue dynamic; the suitable local bio-socioecological environment is the fundamental factor for dengue epidemics. The Bio8 [odds ratio (OR) = 2.11, 95% confidence interval (CI): 1.67-2.68], Bio9 (OR = 291.62, 95% CI: 125.63-676.89), Bio15 (OR = 4.15, 95% CI: 3.30-5.24), normalized difference vegetation index in March (OR = 1.27, 95% CI: 1.06-1.51) and July (OR = 1.04, 95% CI: 1.00-1.07), and the imported cases are the major drivers of dengue local transmissions (OR = 4.79, 95% CI: 4.34-5.28). The intermediary effect of an index on population and economic development to local cases via the path of imported cases was detected in the dengue dynamic system. CONCLUSIONS: Dengue outbreaks in China are triggered by introductions of imported cases and boosted by landscape features and connectivity. Our research will contribute to developing nature-based solutions for dengue surveillance, mitigation, and control from a socio-ecological perspective based on invasion ecology theories to control and prevent future dengue invasion and localization.
Subject(s)
Dengue , Epidemics , Humans , Dengue/epidemiology , Disease Outbreaks/prevention & control , China/epidemiology , ForecastingABSTRACT
A 36-year-old Asian Indian male presented with redness and pain in his right eye of 1 week duration. He was diagnosed to have right acute anterior uveitis and had a history of being admitted at a local hospital for dengue hepatitis a month earlier. He had been on adalimumab 40 mg three weekly once and oral methotrexate 20 mg/week for human leucocyte antigen (HLA) B27 spondyloarthropathy and recurrent anterior uveitis. Our patient had re-activation of his anterior chamber inflammation on three distinct occasions: first, 3 weeks following recovery from coronavirus disease 2019 (COVID-19), the second after the second dose of COVID-19 vaccination, and the third after recovery from dengue fever-associated hepatitis. We propose molecular mimicry and bystander activation as the postulated mechanisms for the re-activation of his anterior uveitis. In conclusion, patients with auto-immune diseases can have recurrent ocular inflammation following COVID-19 or its vaccination or dengue fever as seen in our patient. The anterior uveitis is usually mild and responds to topical steroids. Additional immuno-suppression may not be needed. Mild ocular inflammation following vaccination should not deter individuals from getting COVID-19 vaccination.
Subject(s)
COVID-19 , Dengue , Hepatitis A , Hepatitis , Uveitis, Anterior , Uveitis , Humans , Male , Adult , COVID-19 Vaccines/adverse effects , Uveitis, Anterior/diagnosis , Uveitis, Anterior/etiology , Inflammation , HLA-B27 Antigen , Vaccination/adverse effects , Dengue/complications , Dengue/diagnosisABSTRACT
In tropical regions, leptospirosis and dengue fever (DF) are infectious diseases of epidemiological importance and have overlapping symptomatic features. The objective of this study was to identify the factors associated to diagnosing leptospirosis that differentiate it to DF at the initial hospital evaluation. A multicenter retrospective study was conducted comparing confirmed leptospirosis to DF cases. Clinical/laboratory findings were compiled at hospital admission on Reunion Island between 2018 and 2019. Multivariable logistic regression was used to identify the predictors of leptospirosis. In total, 98 leptospirosis and 673 DF patients were included with a mean age of 47.8 (±17.1) and 48.9 (±23.3) years, respectively. In the multivariate analyses, the main parameters associated with leptospirosis were: i) increased neutrophil counts, ii) C-reactive protein values, iii) the absence of prolonged partial thromboplastin time, and iv) a decrease of platelets. The most discriminating parameter was C-reactive protein (CRP). With a threshold of 50mg/L, CRP taken alone had a sensitivity of 94% and a specificity of 93.5%. The positive and negative likelihood ratios were 14.5 and 0.06, respectively. In the setting of an early presumptive diagnosis, we found that an increased CRP value (>50 mg/L) could help diagnose leptospirosis and aid the decision process for hospital surveillance and/or a potential antibiotic treatment regimen.
Subject(s)
Dengue , Leptospirosis , Humans , Middle Aged , Dengue/diagnosis , Dengue/epidemiology , C-Reactive Protein , Retrospective Studies , Leptospirosis/diagnosis , Leptospirosis/epidemiology , Logistic ModelsABSTRACT
BACKGROUND: An unprecedent increase in the number of cases and deaths reported from dengue virus (DENV) infection has occurred in the southwestern Indian ocean in recent years. From 2017 to mid-2021 more than 70,000 confirmed dengue cases were reported in Reunion Island, and 1967 cases were recorded in the Seychelles from 2015 to 2016. Both these outbreaks displayed similar trends, with the initial circulation of DENV-2 which was replaced by DENV-1. Here, we aim to determine the origin of the DENV-1 epidemic strains and to explore their genetic characteristics along the uninterrupted circulation, particularly in Reunion. METHODS: Nucleic acids were extracted from blood samples collected from dengue positive patients; DENV-1 was identified by RT-qPCR. Positive samples were used to infect VERO cells. Genome sequences were obtained from either blood samples or infected-cell supernatants through a combination of both Illumina or MinION technologies. RESULTS: Phylogenetic analyses of partial or whole genome sequences revealed that all DENV-1 sequences from Reunion formed a monophyletic cluster that belonged to genotype I and were closely related to one isolate from Sri Lanka (OL752439.1, 2020). Sequences from the Seychelles belonged to the same major phylogenetic branch of genotype V, but fell into two paraphyletic clusters, with greatest similarity for one cluster to 2016-2017 isolate from Bangladesh, Singapore and China, and for the other cluster to ancestral isolates from Singapore, dating back to 2012. Compared to publicly available DENV-1 genotype I sequences, fifteen non-synonymous mutations were identified in the Reunion strains, including one in the capsid and the others in nonstructural proteins (NS) (three in NS1, two in NS2B, one in NS3, one in NS4B, and seven in NS5). CONCLUSION: In contrast to what was seen in previous outbreaks, recent DENV-1 outbreaks in Reunion and the Seychelles were caused by distinct genotypes, all likely originating from Asia where dengue is (hyper)endemic in many countries. Epidemic DENV-1 strains from Reunion harbored specific non-synonymous mutations whose biological significance needs to be further investigated.
Subject(s)
Dengue Virus , Dengue , Animals , Chlorocebus aethiops , Humans , Dengue/epidemiology , Serogroup , Reunion/epidemiology , Phylogeny , Seychelles , Vero Cells , Disease Outbreaks , Genotype , Sri LankaSubject(s)
Alopecia Areata , Dengue , Humans , Acute Disease , Dengue/complications , Dengue/diagnosisABSTRACT
Social media usage is growing globally, with an exponential increase in low- and middle-income countries. Social media changes the ways in which information-sharing occurs, intensifying the population's exposure to misinformation, including fake news. This has important repercussions for global health. The spread of fake news can undermine the implementation of evidence-based interventions and weaken the credibility of scientific expertise. This is particularly worrisome in countries, such as Brazil, in a sociopolitical context characterized by a lack of popular trust in public institutions. In this project report, we describe our experience with the spread of fake news through the social media platform WhatsApp during the implementation of a cluster randomized controlled trial aimed at reducing dengue incidence in children in Fortaleza (Brazil). During initial visits to selected clusters, the research team was met with resistance. Then, soon after data collection started, fake news began circulating about the study. As a result, the research team developed strategies to dispel suspicion and further promote the study. However, the climate of violence and mistrust, coupled with the COVID-19 pandemic, forced the interruption of the study in 2019. The lessons learned from our experience in Fortaleza can be useful to other researchers and practitioners implementing large-scale interventions in this era of health-related misinformation.
Subject(s)
COVID-19 , Dengue , Social Media , Child , Humans , COVID-19/epidemiology , Global Health , Brazil/epidemiology , Pandemics , Disinformation , Dengue/epidemiologyABSTRACT
AT-752 is a guanosine analogue prodrug active against dengue virus (DENV). In infected cells, it is metabolized into 2'-methyl-2'-fluoro guanosine 5'-triphosphate (AT-9010) which inhibits RNA synthesis in acting as a RNA chain terminator. Here we show that AT-9010 has several modes of action on DENV full-length NS5. AT-9010 does not inhibit the primer pppApG synthesis step significantly. However, AT-9010 targets two NS5-associated enzyme activities, the RNA 2'-O-MTase and the RNA-dependent RNA polymerase (RdRp) at its RNA elongation step. Crystal structure and RNA methyltransferase (MTase) activities of the DENV 2 MTase domain in complex with AT-9010 at 1.97 Å resolution shows the latter bound to the GTP/RNA-cap binding site, accounting for the observed inhibition of 2'-O but not N7-methylation activity. AT-9010 is discriminated â¼10 to 14-fold against GTP at the NS5 active site of all four DENV1-4 NS5 RdRps, arguing for significant inhibition through viral RNA synthesis termination. In Huh-7 cells, DENV1-4 are equally sensitive to AT-281, the free base of AT-752 (EC50 ≈ 0.50 µM), suggesting broad spectrum antiviral properties of AT-752 against flaviviruses.
Subject(s)
Dengue Virus , Dengue , Humans , Dengue Virus/physiology , Viral Nonstructural Proteins/genetics , RNA, Viral/metabolism , Dengue/drug therapy , Guanosine/pharmacology , Guanosine/metabolism , Guanosine Triphosphate/metabolism , Virus ReplicationSubject(s)
COVID-19 , Chikungunya Fever , Dengue , Humans , Chikungunya Fever/epidemiology , Paraguay , Dengue/epidemiology , Disease OutbreaksABSTRACT
BACKGROUND: Dengue is a common viral illness and severe disease results in life-threatening complications. Healthcare services in low- and middle-income countries treat the majority of dengue cases worldwide. However, the clinical decision-making processes which result in effective treatment are poorly characterised within this setting. In order to improve clinical care through interventions relating to digital clinical decision-support systems (CDSS), we set out to establish a framework for clinical decision-making in dengue management to inform implementation. METHODS: We utilised process mapping and task analysis methods to characterise existing dengue management at the Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam. This is a tertiary referral hospital which manages approximately 30,000 patients with dengue each year, accepting referrals from Ho Chi Minh city and the surrounding catchment area. Initial findings were expanded through semi-structured interviews with clinicians in order to understand clinical reasoning and cognitive factors in detail. A grounded theory was used for coding and emergent themes were developed through iterative discussions with clinician-researchers. RESULTS: Key clinical decision-making points were identified: (i) at the initial patient evaluation for dengue diagnosis to decide on hospital admission and the provision of fluid/blood product therapy, (ii) in those patients who develop severe disease or other complications, (iii) at the point of recurrent shock in balancing the need for fluid therapy with complications of volume overload. From interviews the following themes were identified: prioritising clinical diagnosis and evaluation over existing diagnostics, the role of dengue guidelines published by the Ministry of Health, the impact of seasonality and caseload on decision-making strategies, and the potential role of digital decision-support and disease scoring tools. CONCLUSIONS: The study highlights the contemporary priorities in delivering clinical care to patients with dengue in an endemic setting. Key decision-making processes and the sources of information that were of the greatest utility were identified. These findings serve as a foundation for future clinical interventions and improvements in healthcare. Understanding the decision-making process in greater detail also allows for development and implementation of CDSS which are suited to the local context.
Subject(s)
Decision Support Systems, Clinical , Dengue , Humans , Clinical Decision-Making , Dengue/diagnosis , Dengue/therapy , Risk Factors , Referral and ConsultationABSTRACT
BACKGROUND AND OBJECTIVES: Paediatric dengue-associated acute liver failure (PALF) is a rare and fatal complication. To date, clinical data regarding the combination of therapeutic plasma exchange (TPE) and continuous renal replacement therapy (CRRT) for the treatment of dengue-associated PALF are limited. METHODS: We conducted a single-center, retrospective study of all children with dengue-associated PALF admitted to the paediatric intensive care unit of Children Hospital No.2, Vietnam, who were treated with TPE+CRRT between January 2021 and March 2022. The main study outcomes were in-hospital survival, normalisation of hepatic function, and hepatic encephalopathy improvement. RESULTS: Twelve patients aged from 06 to 12 years underwent TPE+CRRT procedures. Among them, three (25 %) patients died of severe sepsis and septic shock confirmed by Enterobacteriaceae spp. haemocultures (stable on maintenance treatment of COVID-19-associated MIS-C with low dose of oral steroids on hospital admission), acute respiratory distress syndrome (ARDS), and clinically apparent intracranial haemorrhage. Nine patients (75 %) survived. The paediatric mortality risk score improved significantly at discharge compared with PICU admission (P < 0.01). Markedly, all twelve patients were diagnosed with hepatoencephalopathy of grades III and IV on PICU admission. After the combined TPE+CRRT interventions, there were substantial improvements in liver transaminases levels, coagulation profiles, and metabolic biomarkers. Normal neurological functions were observed in nine alive patients at hospital discharge. Only one patient experienced an adverse event of slightly low blood pressure, which rapidly self-resolved. INTERPRETATION AND CONCLUSIONS: Combined TPE+CRRT significantly improved survival outcome, neurological status, and rapid normalisation of liver functions in dengue-associated PALF.
Subject(s)
Acute Kidney Injury , COVID-19 , Continuous Renal Replacement Therapy , Dengue , Liver Failure, Acute , Child , Humans , Plasma Exchange/methods , Retrospective Studies , Vietnam , COVID-19/therapy , Liver Failure, Acute/etiology , Liver Failure, Acute/therapyABSTRACT
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has affected >370 million individuals worldwide. Dengue is endemic in many countries and leads to epidemics at frequent intervals. In the tropics and subtropics, it is possible that individuals may be concurrently infected with both dengue and SARS-CoV-2. Differentiation between the two infections may be difficult from both a clinical and laboratory perspective. We have outlined the currently published findings (as of the end of December 2021) on patients with dengue and SARS-CoV-2 co-infections and have discussed the observed outcomes and management of such patients. Co-infections were more common in males >25 y of age, fever was not universal, 30-50% had medical comorbidities such as diabetes mellitus or hypertension and the case fatality rate was 16-28%.
Subject(s)
COVID-19 , Coinfection , Dengue , Male , Humans , COVID-19/epidemiology , SARS-CoV-2 , Coinfection/epidemiology , Comorbidity , Dengue/complications , Dengue/epidemiologyABSTRACT
Zika and Dengue are infectious diseases caused by flaviviruses and transmitted by Aedes mosquitoes. Although symptoms are usually mild, complications such as dengue hemorrhagic fever and microcephaly in newborns -after the pregnant woman becomes infected with the Zika virus-have emerged as a global public health concern. The co-circulation of Zika and Dengue viruses and the overlapping of their symptoms represent a challenge for the accurate diagnosis. A single test for the point-of-care detection of both diseases is crucial. Here we report a single chip that distinguishes between Zika and Dengue infections using the non-structural protein 1 (NS1) as biomarkers. A novel multiplex electrochemical device containing four independent working electrodes was developed. Zika and Dengue biosensors were fabricated separately on different working electrodes. Selectivity tests showed that the two biosensors can distinguish not only the NS1 proteins from Zika and Dengue but also the spike proteins present in the SARS-CoV-2. This is especially relevant as patients with COVID-19 may have symptoms similar to Zika and Dengue. The gold surface was modified with cysteamine and antibodies against the NS1 proteins. Both biosensors detected their respective biomarkers at clinically relevant concentrations and presented a good linear relationship between the percentage change in impedance and the logarithm of the NS1 concentration (R2 = 0.990 for Dengue and R2 = 0.995 for Zika). Upon combining a simple sample preparation with a portable detection method, our disposable multiplex device offers a point-of-care diagnostic test for Zika and Dengue using a single chip. Additionally, two other biosensors can be added to the chip, providing a platform for viral detection.
Subject(s)
Biosensing Techniques , COVID-19 , Dengue Virus , Dengue , Zika Virus Infection , Zika Virus , Animals , Antibodies, Viral , Biomarkers , Cysteamine , Female , Gold , Humans , Infant, Newborn , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Viral Nonstructural Proteins , Zika Virus Infection/diagnosisABSTRACT
BACKGROUND: The risk of possible cross-reactions between serological tests, together with the clinical similarities between dengue fever and COVID-19, can delay diagnosis and increase the risk of both COVID-19 transmission and worsening. The present study aimed to determine the possibility of cross-reactions among rapid serological tests based on clinical symptoms. METHODS: Patients with COVID-19, confirmed by RT-PCR and clinical criteria for diagnosing dengue, were recruited consecutively between September 2020 and August 2021 and underwent rapid immunochromatographic diagnostic (RID) tests for AgNS1, IgM, and IgG. Patients who tested positive for acute-phase dengue IgM and AgNS1 underwent a follow-up test after 12-30 days for diagnostic confirmation. RESULTS: A total of 43 patients were included, 38 of whom required hospital admission, and 8 received intensive care. Seven patients tested positive on the RID tests, comprising 2 NS1 positive (coinfection), one reactive for IgM and IgG (coinfection), three reactive for IgM not confirmed (false-positive), and one reactive for IgG due to previous infection. Two of the 3 patients with coinfection died. Fever, myalgia, headache, and cough were the most common clinical symptoms, while lymphopenia was the most prevalent laboratory finding. CONCLUSIONS: Cross-reactivity was found in only three patients and coinfection in another three patients, two of whom died of severe COVID-19 manifestations.
Subject(s)
COVID-19 , Coinfection , Dengue , Humans , Dengue/complications , Dengue/diagnosis , Coinfection/diagnosis , Immunoglobulin M , COVID-19/diagnosis , Immunoglobulin G , Antibodies, ViralABSTRACT
With a long epidemic history and a large number of dengue cases, Guangzhou is a key city for controlling dengue in China. The demographic information regarding dengue cases, and the genomic characteristics of the envelope gene of dengue viruses, as well as the associations between these factors were investigated from 2010 to 2019, to improve the understanding of the epidemiology of dengue in Guangzhou. Demographic data on 44,385 dengue cases reported to the Notifiable Infectious Disease Report System were analyzed using IBM SPSS Statistics v. 20. Dengue virus isolates from patient sera were sequenced, and phylogenetic trees were constructed using PhyML 3.1. There was no statistical difference in the risk of dengue infection between males and females. Unlike other areas in which dengue is endemic, the infection risk in Guangzhou increased with age. Surveillance identified four serotypes responsible for dengue infections in Guangzhou. Serotype 1 remained prevalent for most of the study period, whereas serotypes 3 and 4 were prevalent in 2012 and 2010, respectively. Different serotypes underwent genotype and sublineage shifts. The epidemiological characteristics and phylogeny of dengue in Guangzhou suggested that although it has circulated in Guangzhou for decades, it has not been endemic in Guangzhou. Meanwhile, shifts in genotypes, rather than in serotypes, might have caused dengue epidemics in Guangzhou.
Subject(s)
Dengue Virus , Dengue , Male , Female , Humans , Dengue Virus/genetics , Phylogeny , Genotype , China/epidemiology , Serogroup , GenomicsABSTRACT
Commemorating the 2021 ASEAN Dengue Day and advocacy for World Dengue Day, the International Society for Neglected Tropical Diseases (ISNTD) and Asian Dengue Voice and Action (ADVA) Group jointly hosted the ISNTD-ADVA World Dengue Day Forum-Cross Sector Synergies in June 2021. The forum aimed to achieve international and multisectoral coordination to consolidate global dengue control and prevention efforts, share best practices and resources, and improve global preparedness. The forum featured experts around the world who shared their insight, research experience, and strategies to tackle the growing threat of dengue. Over 2,000 healthcare care professionals, researchers, epidemiologists, and policy makers from 59 countries attended the forum, highlighting the urgency for integrated, multisectoral collaboration between health, environment, education, and policy to continue the march against dengue. Sustained vector control, environmental management, surveillance improved case management, continuous vaccine advocacy and research, capacity building, political commitment, and community engagement are crucial components of dengue control. A coordinated strategy based on science, transparency, timely and credible communication, and understanding of human behavior is needed to overcome vaccine hesitancy, a major health risk further magnified by the COVID-19 pandemic. The forum announced a strong call to action to establish World Dengue Day to improve global awareness, share best practices, and prioritize preparedness in the fight against dengue.
Subject(s)
COVID-19 , Dengue , Vaccines , Dengue/epidemiology , Dengue/prevention & control , Humans , Neglected Diseases/epidemiology , PandemicsABSTRACT
Current knowledge of dengue virus (DENV) transmission provides only a partial understanding of a complex and dynamic system yielding a public health track record that has more failures than successes. An important part of the problem is that the foundation for contemporary interventions includes a series of longstanding, but untested, assumptions based on a relatively small portion of the human population; i.e., people who are convenient to study because they manifest clinically apparent disease. Approaching dengue from the perspective of people with overt illness has produced an extensive body of useful literature. It has not, however, fully embraced heterogeneities in virus transmission dynamics that are increasingly recognized as key information still missing in the struggle to control the most important insect-transmitted viral infection of humans. Only in the last 20 years have there been significant efforts to carry out comprehensive longitudinal dengue studies. This manuscript provides the rationale and comprehensive, integrated description of the methodology for a five-year longitudinal cohort study based in the tropical city of Iquitos, in the heart of the Peruvian Amazon. Primary data collection for this study was completed in 2019. Although some manuscripts have been published to date, our principal objective here is to support subsequent publications by describing in detail the structure, methodology, and significance of a specific research program. Our project was designed to study people across the entire continuum of disease, with the ultimate goal of quantifying heterogeneities in human variables that affect DENV transmission dynamics and prevention. Because our study design is applicable to other Aedes transmitted viruses, we used it to gain insights into Zika virus (ZIKV) transmission when during the project period ZIKV was introduced and circulated in Iquitos. Our prospective contact cluster investigation design was initiated by detecttion of a person with a symptomatic DENV infection and then followed that person's immediate contacts. This allowed us to monitor individuals at high risk of DENV infection, including people with clinically inapparent and mild infections that are otherwise difficult to detect. We aimed to fill knowledge gaps by defining the contribution to DENV transmission dynamics of (1) the understudied majority of DENV-infected people with inapparent and mild infections and (2) epidemiological, entomological, and socio-behavioral sources of heterogeneity. By accounting for factors underlying variation in each person's contribution to transmission we sought to better determine the type and extent of effort needed to better prevent virus transmission and disease.
Subject(s)
Arboviruses , Dengue Virus , Dengue , Zika Virus Infection , Zika Virus , Humans , Longitudinal Studies , Prospective Studies , Peru/epidemiology , Zika Virus Infection/epidemiologyABSTRACT
Numerous investigations of the spatiotemporal patterns of infectious disease epidemics, their potential influences, and their driving mechanisms have greatly contributed to effective interventions in the recent years of increasing pandemic situations. However, systematic reviews of the spatiotemporal patterns of communicable diseases are rare. Using bibliometric analysis, combined with content analysis, this study aimed to summarize the number of publications and trends, the spectrum of infectious diseases, major research directions and data-methodological-theoretical characteristics, and academic communities in this field. Based on 851 relevant publications from the Web of Science core database, from January 1991 to September 2021, the study found that the increasing number of publications and the changes in the disease spectrum have been accompanied by serious outbreaks and pandemics over the past 30 years. Owing to the current pandemic of new, infectious diseases (e.g., COVID-19) and the ravages of old infectious diseases (e.g., dengue and influenza), illustrated by the disease spectrum, the number of publications in this field would continue to rise. Three logically rigorous research directions-the detection of spatiotemporal patterns, identification of potential influencing factors, and risk prediction and simulation-support the research paradigm framework in this field. The role of human mobility in the transmission of insect-borne infectious diseases (e.g., dengue) and scale effects must be extensively studied in the future. Developed countries, such as the USA and England, have stronger leadership in the field. Therefore, much more effort must be made by developing countries, such as China, to improve their contribution and role in international academic collaborations.