Adaptation of the CUGH global health competency framework in the Chinese context: a mixed-methods study.

BACKGROUND: In 2014, the Consortium of Universities for Global Health (CUGH) developed a global health competency framework and called for its validation. Given China's increasing engagement in global health over the past decade, there is a need for a tailored competency framework to enhance the capacity of its workforce. This study aimed to localize the CUGH global health framework within the Chinese context, offering guidance to public health professionals in China to bolster their capabilities for international endeavors. METHODS: Employing a modified Delphi consultation approach, this study adapted the CUGH global health competency framework through three consultation rounds and a panel discussion. A questionnaire employing a five-point Likert scale was developed to gather opinions from 37 experts on the significance and feasibility of each competency within the Chinese setting. Profiling information, judgment criteria, and familiarity with each competency were collected to assess experts' authority levels. Furthermore, a priority survey was administered to 51 experts to identify key competencies and provide recommendations for bolstering the capabilities of China's public health professionals. Data analysis was performed using Microsoft Excel. RESULTS: The adapted framework comprises 10 domains and 37 competencies including: 1. Global Burden of Disease; 2. Social-economic, Environmental and Behavioral Determinants of Health; 3. The Impact of Globalization on Population Health, Health Systems, and Healthcare; 4. Major Global health initiatives and efforts; 5. Ethics, Health Equity and Social Justice; 6. Sociocultural, Political Awareness and Policy Promotion; 7. Personal Competencies and Professional Practice; 8. Capacity strengthening; 9. Collaboration, Partnering and Communication; 10. Programme Management. The priority survey underscored Domain 9, 10, and 4 as the foremost concern for Chinese public health professionals, urging active learning, critical thinking, open communication, experiential learning, and case-based studies. Institutions were advised to enhance their capacity, foster partnerships, and discern China's distinct role in the global health arena. CONCLUSIONS: This study adapted the CUGH framework within the Chinese context, evaluating the significance and feasibility of each competency. The adapted framework can serve as a tool for developing global health curricula and delineating roles for Chinese public health professionals. To ensure contextual compatibility, testing of the framework with diverse public health professionals is recommended, enabling precise refinement of competencies based on empirical results.

Prevalence trend and burden of neglected parasitic diseases in China from 1990 to 2019: findings from global burden of disease study.

Objective: This study sought to investigate the parasitic diseases of neglected tropical diseases defined by the World Health Organization based on the Global Burden of Disease Study (GBD) database. Importantly, we analyzed the prevalence and burden of these diseases in China from 1990 to 2019 to provide valuable information to formulate more effective measures for their management and prevention. Methods: Data on the prevalence and burden of neglected parasitic diseases in China from 1990 to 2019 were extracted from the global health data exchange (GHDx) database, including the absolute number of prevalence, age-standardized prevalence rate, disability-adjusted life year (DALY) and age-standardized DALY rate. Descriptive analysis was used to analyze the prevalence and burden changes, sex and age distribution of various parasitic diseases from 1990 to 2019. A time series model [Auto-Regressive Integrated Moving Average (ARIMA)] was used to predict the DALYs of neglected parasitic diseases in China from 2020 to 2030. Results: In 2019, the number of neglected parasitic diseases in China was 152518062, the age-standardized prevalence was 11614.1 (95% uncertainty interval (UI) 8758.5-15244.5), the DALYs were 955722, and the age-standardized DALY rate was 54.9 (95% UI 26.0-101.8). Among these, the age-standardized prevalence of soil-derived helminthiasis was the highest (9370.2/100,000), followed by food-borne trematodiases (1502.3/100,000) and schistosomiasis (707.1/100,000). The highest age-standardized DALY rate was for food-borne trematodiases (36.0/100,000), followed by cysticercosis (7.9/100,000) and soil-derived helminthiasis (5.6/100,000). Higher prevalence and disease burden were observed in men and the upper age group. From 1990 to 2019, the number of neglected parasitic diseases in China decreased by 30.4%, resulting in a decline in DALYs of 27.3%. The age-standardized DALY rates of most diseases were decreased, especially for soil-derived helminthiasis, schistosomiasis and food-borne trematodiases. The ARIMA prediction model showed that the disease burden of echinococcosis and cysticercosis exhibited an increasing trend, highlighting the need for further prevention and control. Conclusion: Although the prevalence and disease burden of neglected parasitic diseases in China have decreased, many issues remain to be addressed. More efforts should be undertaken to improve the prevention and control strategies for different parasitic diseases. The government should prioritize multisectoral integrated control and surveillance measures to prioritize the prevention and control of diseases with a high burden of disease. In addition, the older adult population and men need to pay more attention.

Cryptosporidiosis threat under climate change in China: prediction and validation of habitat suitability and outbreak risk for human-derived Cryptosporidium based on ecological niche models.

BACKGROUND: Cryptosporidiosis is a zoonotic intestinal infectious disease caused by Cryptosporidium spp., and its transmission is highly influenced by climate factors. In the present study, the potential spatial distribution of Cryptosporidium in China was predicted based on ecological niche models for cryptosporidiosis epidemic risk warning and prevention and control. METHODS: The applicability of existing Cryptosporidium presence points in ENM analysis was investigated based on data from monitoring sites in 2011-2019. Cryptosporidium occurrence data for China and neighboring countries were extracted and used to construct the ENMs, namely Maxent, Bioclim, Domain, and Garp. Models were evaluated based on Receiver Operating Characteristic curve, Kappa, and True Skill Statistic coefficients. The best model was constructed using Cryptosporidium data and climate variables during 1986‒2010, and used to analyze the effects of climate factors on Cryptosporidium distribution. The climate variables for the period 2011‒2100 were projected to the simulation results to predict the ecological adaptability and potential distribution of Cryptosporidium in future in China. RESULTS: The Maxent model (AUC = 0.95, maximum Kappa = 0.91, maximum TSS = 1.00) fit better than the other three models and was thus considered the best ENM for predicting Cryptosporidium habitat suitability. The major suitable habitats for human-derived Cryptosporidium in China were located in some high-population density areas, especially in the middle and lower reaches of the Yangtze River, the lower reaches of the Yellow River, and the Huai and the Pearl River Basins (cloglog value of habitat suitability > 0.9). Under future climate change, non-suitable habitats for Cryptosporidium will shrink, while highly suitable habitats will expand significantly (χ2 = 76.641, P < 0.01; χ2 = 86.836, P < 0.01), and the main changes will likely be concentrated in the northeastern, southwestern, and northwestern regions. CONCLUSIONS: The Maxent model is applicable in prediction of Cryptosporidium habitat suitability and can achieve excellent simulation results. These results suggest a current high risk of transmission and significant pressure for cryptosporidiosis prevention and control in China. Against a future climate change background, Cryptosporidium may gain more suitable habitats within China. Constructing a national surveillance network could facilitate further elucidation of the epidemiological trends and transmission patterns of cryptosporidiosis, and mitigate the associated epidemic and outbreak risks.

Investigation of Parasitic Nematodes Detected in the Feces of Wild Carnivores in the Eastern Qinghai-Tibet Plateau, China.

Wildlife shares grazing areas with herders in the eastern Qinghai-Tibet Plateau, and humans can be infected by zoonotic nematodes through direct contact with animals or contaminated water. In this study, fecal samples (n = 296) from wild carnivores were collected to explore the infection rate and molecular genetic characteristics of nematodes by stratified random sampling in the survey areas. Host species and the nematodes they carried were then identified using 16S rRNA and 18S rRNA gene sequencing, respectively. Statistical analysis, neutrality tests, genetic diversity analysis and Bayesian inferred trees were performed to complete the study. In total, 10 species of nematodes were detected in 240 feces from six species of carnivores identified (including dominant Vulpes ferrilata and Vulpes vulpes), namely Uncinaria stenocephala, Toxascaris sp., Crenosoma vulpis, Parapharyngodon bainae, Oesophagostomum muntiacum, Aspiculuris tetraptera, Mastophorus muris, Nematodirus spathiger, Muellerius capillaris, and Molineus patens. Among these nematodes, U. stenocephala (35.83%, 86/240) and Toxascaris sp. (14.58%, 35/240) were detected at higher rates than the other nematodes (χ2 = 516.909, p < 0.05). Of 17 and 18 haplotypes were found based on the ITS1 gene for U. stenocephala and nad1 gene for Toxascaris sp., respectively. For the first time, using molecular methods, we report the infection of V. ferrilata by U. stenocephala, a potential zoonotic parasite, and suggest Toxascaris sp. may be a newly discovered nematode that lives within the fox intestine.

A Knowledge Survey on Health Education of Echinococcosis Among Students - Ganzi Tibetan Autonomous Prefecture, Sichuan Province, China, 2020.

What is already known about this topic?: Previous surveys have mainly focused on how well residents and primary school students have understood the core knowledge of echinococcosis control and are limited in terms of the comprehensiveness of the knowledge category and respondents. What is added by this report?: There were some shortcomings in related knowledge of echinococcosis among students, which showed a tendency to know methods but not the rationale. The differences among regions indicated a lack of a unified system for training educators and allocating comprehensive educational material. What are the implications for public health practices?: The results of this study provide evidence to potentially help improve health education programs in the new phase of echinococcosis prevention and control in China.

Strengthening capacity-building in malaria and schistosomiasis control under China-Africa cooperation: Assessing a case study of Burkina Faso.

Malaria and schistosomiasis are highly prevalent in Burkina Faso, whereas China has successfully eliminated malaria as well as schistosomiasis as a public health problem. To implement the China-Africa health cooperation initiative, a series of activities were launched since 2019 to enhance understanding and cooperation among malaria and schistosomiasis professionals in China and Burkina Faso. This study described the achievements of the First Virtual Symposium of China-Burkina Faso Cooperation on Schistosomiasis and Malaria Control. Pre- and post-test questionnaires were employed to study the knowledge changes of participants regarding malaria and schistosomiasis control and elimination, explore capacity-building priorities, and identify potential challenges. Chi-squared statistics were used to compare the differences between sub-groups, and p value < 0.05 was considered statistically significant. Participants ranked their preferences for challenges and capacity-building priorities in future cooperation. The responses of participants from both China and Burkina Faso indicated effective improvement in their general knowledge about the diseases whereas the improvement in professional knowledge on malaria and schistosomiasis was limited. The total correct response rate increased from 54.08% to 66.78%. Chinese participants had better schistosomiasis knowledge than Burkina Faso participants did, but the same result was not found for malaria. Diseases control strategies, surveillance and response system, and diagnostics techniques were identified as the top three priorities for future capacity building. Participants from China and Burkina Faso shared almost the same views about challenges except with respect to pathogens, which the former saw as a major challenge and the latter did not. The study findings will help policymakers, health managers, and researchers to understand the future cooperation between Burkina Faso and China on malaria and schistosomiasis.

Prevalence of Echinococcus Species in Wild Foxes and Stray Dogs in Qinghai Province, China.

Echinococcosis is a zoonotic parasitic disease that is highly endemic to the Qinghai province of China. Limited data are available on the prevalence of the causal pathogen, Echinococcus spp., in definitive hosts in this region. Thus, the aim of this study was to evaluate the prevalence of Echinococcus spp. in wild foxes and stray dogs in Qinghai province. Five hundred and twenty-eight feces from wild foxes and 277 from stray dogs were collected from 11 counties in the Golog, Yushu, and Haixi prefectures and screened for Echinococcus spp. using copro-DNA polymerase chain reaction (PCR). In total, 5.5% of wild foxes and 15.2% of stray dogs tested positive for Echinococcus spp. The prevalence rates of Echinococcus spp. in wild foxes in Golog, Yushu, and Haixi were 7.3%, 5.2%, and 1.9%, respectively. In stray dogs, these rates were 13.3%, 17.3%, and 0%, respectively. Sequencing analysis determined that Echinococcus multilocularis was the most prevalent species, occurring in 4.0% and 12.6% of wild foxes and stray dogs, respectively. Echinococcus shiquicus was observed in 1.5% of wild foxes and 0.7% of stray dogs. Echinococcus granulosus was observed only in wild dogs, with a prevalence rate of 1.8%. To our knowledge, this is the first report on the prevalence of E. shiquicus in dogs in Qinghai province. The current results improve our understanding of the transmission and dissemination of human echinococcosis and suggest that exposure to the eggs of E. multilocularis harbored by wild foxes and stray dogs may pose a great risk of alveolar echinococcosis to humans in Qinghai province.

The pathology, phylogeny, and epidemiology of Echinococcus ortleppi (G5 genotype): a new case report of echinococcosis in China.

BACKGROUND: Cystic echinococcosis (CE), caused by the larval stage of the complex Echinococcus granulosus sensu lato (s.l.), is a zoonotic parasitic disease with a high social burden in China. E. ortleppi is a species (formerly genotype 5 of E. granulosus s.l.) with unique epidemic areas (tropical areas), transmission patterns (mainly cattle origin), and pathological characteristics (large and small hook lengths) compared to other species that cause CE. A 19-year-old female patient in an area with no history of echinococcosis in Guizhou Province, China, was diagnosed with E. ortleppi infection in 2019. This study is to understand the source of this human E. ortleppi infection. METHODS: We performed computer tomography (CT) scans, surgical operation, morphological sectioning, molecular diagnosis, phylogenetic analyses, and epidemiological investigation in Anshun City, Guizhou Province, China in 2019. RESULTS: The patient presented with intermittent distension and pain in the upper abdomen without other abnormal symptoms. Routine blood examination results were normal. However, abdominal CT revealed a fertile cyst with a diameter of approximately 8 cm, uniform density, and a clear boundary, but without an evident cyst wall in the right lobe of the liver. The cyst was fertile, and phylogenetic analyses revealed that the isolates represented a new E. ortleppi genus haplotype. A result of 10‒14 years incubation period with indigenous infection was considered available for the case through the epidemiological survey. CONCLUSIONS: CE due to E. ortleppi infection can be confused with other diseases causing liver cysts, resulting in misdiagnosis. A transmission chain of E. ortleppi may exist or existed in the past in the previously considered non-endemic areas of echinococcosis in southwestern China.

Challenges of Sustaining Malaria Community Case Management in 81 Township Hospitals along the China-Myanmar Border Region - Yunnan Province, China, 2020.

What is already known on this topic? The health workforce at township hospitals in the China-Myanmar border region has played a key role in sustaining Community case management of malaria (CCMm), while few studies have investigated their performance and challenges. What is added by this report? Sustaining CCMm in the region was subject to the following major challenges: insufficient training on malaria diagnosis and testing, lacking necessary and timely treatment for patients, and risks of instability among the malaria workforce. What are the implications for public health practice? These challenges called for the national and provincial authorities to provide regular trainings and intensive supervision to strengthen malaria diagnosis and treatment capacity in the region and to set up incentive mechanisms and individual career development paths to sustain the workforce.

Deployment of workforce in global health: what should be the priorities for China?

BACKGROUND: China has increasingly emerged as an important player in global health. However, compared to developed countries, China still lacks a sufficient health workforce for global health engagement with the necessary competencies required. The world has recognized that to solve global health issues, the role of China needs to be strengthened. The priorities for the deployment of the Chinese workforce in global health remain unclear. This study aims to identify the priorities of the deployment of Chinese global health workforce by exploring the core competencies for Chinese global health workforce, factors influencing the deployment and the approach of deployment. METHODS: Quantitative descriptive statistical analysis was applied to analyze the quantitative data. A total of 148 key respondents from 10 provinces in China conducting global health projects over the last 3 years were selected as the study subjects. A structured questionnaire was developed to collect the data on four aspects, including general information, core competencies, factors influencing deployment, and mode of deployment. The questionnaire was distributed to the respondents through an online survey. All original data were exported to Microsoft Excel 2010 to calculate the frequencies and percentages of each option. A descriptive analysis was carried out of the priorities of deployment of the Chinese global health workforce. RESULTS: More than half of the respondents (51.4%, 76/148) regarded "communication" as the most important competency of the Chinese global health workforce, while a large proportion of participants from Chinese embassies (50.0%, 6/12) and international organizations (75.0%, 12/16) believed that "professional skills" were paramount. In addition, 58.1% (86/148) of the participants agreed that incentive factors (salary, professional position, etc.) were the main factors that influenced deployment, whereas 75% (12/16) of participants from international organizations emphasized "security" as the most important determinant. In addition, 60.8% (90/148) of the participants thought that the deployment of staff should be based on the needs of the global health project implementation. CONCLUSIONS: This study highlights the deployment priorities of the Chinese global health workforce, including strengthening communication and professional skills, focusing on personal security and incentives, and catering to the project implementation. This study also highlights the importance of Chinese agencies in developing global health mindsets through global health practices and proactive integration within the global community.

Research capacity of global health institutions in China: a gap analysis focusing on their collaboration with other low-income and middle-income countries.

INTRODUCTION: This paper presented qualitative and quantitative data collected on the research capacity of global health institutions in China and aimed to provide a landscaping review of the development of global health as a new discipline in the largest emerging economy of the world. METHODS: Mixed methods were used and they included a bibliometric analysis, a standardised survey and indepth interviews with top officials of 11 selected global health research and educational institutions in mainland China. RESULTS: The bibliometric analysis revealed that each institution had its own focus areas, some with a balanced focus among chronic illness, infectious disease and health systems, while others only focused on one of these areas. Interviews of key staff from each institution showed common themes: recognition that the current research capacity in global health is relatively weak, optimism towards the future, as well as an emphasis on mutual beneficial networking with other countries. Specific obstacles raised and the solutions applied by each institution were listed and discussed. CONCLUSION: Global health institutions in China are going through a transition from learning and following established protocols to taking a more leading role in setting up China's own footprint in this area. Gaps still remain, both in comparison with international institutions, as well as between the leading Chinese institutions and those that have just started. More investment needs to be made, from both public and private domains, to improve the overall capacity as well as the mutual learning and communication within the academic community in China.

Advances in research on echinococcoses epidemiology in China.

Echinococcoses are serious zoonotic diseases in China's vast, western and north-western pastoral areas that has one of the highest prevalence in the world. The two most common forms, cystic echinococcosis (CE) and alveolar echinococcosis (AE), are co-epidemic in some areas causing a grave threat to people's health and economic development. Echinococcus spp. are transmitted through domestic, sylvatic and mixed cycles involving many kinds of host. Successful transmission requires a favourable environment for the growth of the parasites and survival of their eggs, while the unique customs and religious beliefs in the endemic areas pose a challenge to the prevention and control of these parasites. Based on previous epidemiological studies, this paper reviews the particular factors affecting the transmission of Echinococcus parasites in China, with a focus on biological (parasite genotype and the species, age, sex and density of hosts), environmental (landscape and climate) and social (age, gender, ethnicity, education, occupation, life style, cultural customs, living conditions and hygiene practices of humans in the endemic areas). These three factors interact with each other and jointly determine the parasites' transmission intensity, the study of which supports the formulation of the strategies and measures that are significant for control of these infections.

Assessment of China's contributions to the Regional Network for Asian Schistosomiasis and Other Helminth Zoonoses: a questionnaire survey.

BACKGROUND: The Regional Network for Asian Schistosomiasis and Other Helminth Zoonoses (RNAS+) was established in 1998, which has developed close partnerships with Asian countries endemic for schistosomiasis and other helminthiasis in Asia. RNAS+ has provided an ideal regional platform for policy-makers, practitioners and researchers on the prevention, control and research of parasitic diseases in Asian countries. China, one of the initiating countries, has provided significant technical and financial support to the regional network. However, its roles and contributions have not been explored so far. The purpose of this study was to assess China's contributions on the supporting of RNAS+ development. METHODS: An assessment research framework was developed to evaluate China's contributions to RNAS+ in four aspects, including capacity building, funding support, coordination, and cooperation. An anonymous web-based questionnaire was designed to acquire respondents' basic information, and information on China's contributions, challenges and recommendations for RNAS+development. Each participant scored from 0 to 10 to assess China's contribution: "0" represents no contribution, and "10" represents 100% contribution. Participants who included their e-mail address in the 2017-2019 RNAS+ annual workshops were invited to participate in the assessment. RESULTS: Of 71 participants enrolled, 41 responded to the survey. 37 (37/41, 90.24%) of them were from RNAS+ member countries, while the other 4 (4/41, 9.76%) were international observers. Most of the respondents (38/41, 92.68%) were familiar with RNAS+. Respondents reported that China's contributions mainly focused on improving capacity building, providing funding support, coordination responsibility, and joint application of cooperation programs on RNAS+ development. The average scores of China's contributions in the above four fields were 8.92, 8.64, 8.75, and 8.67, respectively, with an overall assessment score of 8.81 (10 for a maximum score). The challenge of RNAS+ included the lack of sustainable funding, skills, etc. and most participants expressed their continual need of China's support. CONCLUSIONS: This survey showed that China has played an important role in the development of RNAS+ since its establishment. This network-type organization for disease control and research can yet be regarded as a great potential pattern for China to enhance regional cooperation. These findings can be used to promote future cooperation between China and other RNAS+ member countries.

Analysis of Factors Influencing Cystic Echinococcosis in Northwest Non-Qinghai Tibetan Plateau Regions of China.

Cystic echinococcosis (CE) is an important health problem in northwest non-Qinghai Tibetan Plateau regions of China. Understanding CE risk factors may help in formulating effective prevention and control measures. In the current study, negative binomial regression was used to analyze CE-related factors using prevalence data from 147 counties (cities, districts, and banners) in northwest non-Qinghai Tibetan Plateau regions of China gathered from a national survey conducted in 2012, county economic data, and livestock production data for 2012. The negative binomial regression models indicated Echinococcus granulosus infection rate in livestock (odds ratio [OR]: 1.0471, 95% CI: 1.0128-1.0825, P = 0.0067), the mean number of dogs per family (OR: 3.0589, 95% CI: 1.5116-6.1900, P = 0.0019), the mean number of sheep per family (OR: 1.0431, 95% CI: 1.0027-1.0852, P = 0.0365), and the source of drinking water (OR: 0.9808, 95% CI: 0.9627-0.9992, P = 0.0413) were correlated with human CE prevalence, whereas altitude, surface temperature, economy, and mean number of cattle per family had a negative association. We found that the positive rate of dog stool coproantigen of Echinococcus was associated with human CE prevalence using the univariate analysis but not after controlling for covariates including the number of dogs per family. This might be partially due to the deworming campaigns that were carried out in most of the researched areas. Therefore, the positive rate of dog stool coproantigen of Echinococcus could not reflect the dog infection rate under natural conditions. These findings indicate that dogs and livestock play the most important role in CE transmission. Further studies should be carried out at the township or village level.

From parasitic disease control to global health: New orientation of the National Institute of Parasitic Diseases, China CDC.

As the only specialized institution for research and control of parasitic diseases at the national level in China for almost 70 years, the National Institute of Parasitic Diseases (NIPD) at the Chinese Center for Disease Control and Prevention (China CDC) has been instrumental in supporting the remarkable progress from high prevalence to transmission interruption or low endemicity of several diseases, lymphatic filariasis, malaria and schistosomiasis in particular. This has taken place through technical guidance, emergency response and scientific research as well as providing technical service, education, training, health promotion and international cooperation. With China's increasing involvement in international cooperation and the increased risk for (re)emerging tropical diseases in mind, the Chinese Government designated in 2017 a new Chinese Center for Tropical Disease Research to NIPD. Responding to the expanded responsibilities, the institute is scaling up its activities in several ways: from parasitic diseases to the wider area of tropical diseases; from disease control to disease elimination; from biological research to policy evidences accumulation; and from public health to global health. Based on this new vision and China's previous accomplishments in the areas mentioned, the institute is in a position to move forward with respect to global health and equitable development according to the central principles of the United Nations' Sustainable Development Goals.

A path to cooperation between China and Mongolia towards the control of echinococcosis under the Belt and Road Initiative.

Health is the core of development. Health cooperation between countries plays a pivotal role under the Belt and Road Initiative (B&R). In 2013, China launched its B&R to improve the international cooperation of which health was an important component. As one of the neglected zoonotic diseases, echinococcosis has become a public health concern and is on top of the government agenda among neglected zoonosis in Mongolia. The transmission of the disease involves animal husbandry, and its characteristics determine the prevention and control of such diseases which requires cross-sector collaboration and comprehensive prevention and control strategies. Taking echinococcosis as an entry point and adopting a 'Mongolia-led, China-supported, and results-sharing' approach to public health cooperation will not only contribute to the advancement of Mongolia's national health coverage, but also promoting China's capacity to engage in global health. In this way, it contributes to meeting the sustainable development goals, especially goal 3, target 3.3: by 2030, end the epidemics of AIDS, tuberculosis, malaria and neglected tropical diseases and combat hepatitis, water-borne diseases and other communicable diseases. This paper provides an overview on how the cooperation between China and Mongolia under the context of B&R was initiated, planned and moved forward to implementation. The experience may provide a good model and inform policy and practice for other bilateral cooperations.

New insights on serodiagnosis of trichinellosis during window period: early diagnostic antigens from Trichinella spiralis intestinal worms.

The clinical diagnosis of trichinellosis is difficult because its clinical manifestations are nonspecific. Detection of anti-Trichinella IgG by ELISA using T. spiralis muscle larval excretory-secretory (ES) antigens is the most commonly used serological method for diagnosis of trichinellosis, but the main disadvantage is false negativity during the early stage of infection. There is an obvious window period between Trichinella infection and antibody positivity.During the intestinal stage of Trichinella infection, the ES antigens of intestinal worms (intestinal infective larvae and adults) are exposed to host's immune system at the earliest time and elicit the production of specific anti-Trichinella antibodies. Anti-Trichinella IgG antibodies in infected mice were detectable by ELISA with ES antigens of intestinal worms as soon as 8-10 days post infection (dpi), but ELISA with muscle larval ES antigens did not permit detection of infected mice before 12 dpi. Therefore, the new early antigens from T. spiralis intestinal worms should be screened, identified and characterized for early serodiagnosis of trichinellosis.