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Background: Enhancing regional collaboration in malaria prevention and control is a pivotal strategy for malaria control and elimination in China. The objective of this study is to examine the regional heterogeneity of malaria healthcare-seeking behaviors and diagnosis across various regions in China from 2017 to 2022. Methods: Individual case data from national malaria surveillance databases were utilized. An analysis was conducted to discern the regional variations in the healthcare-seeking behaviors and diagnosis among regions. Results: From 2017 to 2022, a total of 10,943 malaria cases were reported in China, predominantly imported cases (10,929), with significant variations in the distribution of different Plasmodium species among regions (P

Abstract Background Qualified malaria diagnosis competency has contributed to the great achievement of malaria elimination in China. After eliminating malaria, it is still critical to the prevention of re-establishment of malaria transmission in China. This study was aimed to assess the malaria detection competency at national and provincial levels in China at the beginning of malaria post-elimination phase. Methods In the present study, different competency assessment activities on the laboratory malaria diagnosis were carried out for national and provincial malaria diagnostic laboratories based on the WHO scoring schedules, including malaria microscopy or nucleic acid amplification tests (NAAT), at the beginning of malaria post-elimination phase (2021–2022) in China. Results A total of 60 slides for malaria microscopy and 10 specimen for NAAT were included into the WHO External Quality Assessments of malaria parasite qualitative detection and species identification, and the scoring rate was 96.6% (microscopy: 171/177) and 85.0% (NAAT: 17/20), respectively. Moreover, 124 samples were included into the national NAAT quality assessment, and an accuracy of 87.9% (109/124) was found without significance among reference laboratories and non-reference laboratories. Conclusions The findings suggest that there is still a need for sustained strengthening of malaria detection competency, particularly in the areas of parasite counting and detection of low-density parasitemia, to ensure prompt detection of the sources of infection and accurate identification of Plasmodium species, and contribute to case management and focus disposal, thereby effectively preventing the malaria re-establishment.

Abstract Background Plasmodium malariae was always neglected compared with P. falciparum and P. vivax. In the present study, we aimed to describe the epidemiology of reported cases infected with P. malariae in the past decade to raise awareness of the potential threat of this malaria parasite in China. Methods Individual data of malaria cases infected with P. malariae reported in China in the past decade were collected via the China Information System for Disease Control and Prevention and Parasitic Diseases Information Reporting Management System, to explore their epidemiological characteristics. Pearson Chi-square tests or Fisher’s Exact Test was used in the statistical analysis. Results From 2013 to 2022, a total of 581 P. malariae cases were reported in China, and mainly concentrated in 20–59 years old group (P

Malaria is a major public health threat worldwide, and it was also widely prevalent in the history in China, seriously endangering people's health and affecting socioeconomic development. China was certified malaria elimination in 2021 with unremitting efforts since the founding of the People's Republic of China in 1949. This great achievement has been another milestone in the fight against major infectious diseases following the elimination of smallpox, poliomyelitis, leprosy, filariasis, neonatal tetanus and blinding trachoma in China. This paper briefly introduces the malaria burden dynamics and the corresponding malaria transmission risk stratificantions, as well as systematically reviews the evolution of anti-malaria policies and measures from severe epidemic to elimination in China. Meanwhile, five key lessons in malaria control and elimination in China are also briefly summarized. All of the above provide evidences for promoting global malaria eradication and preventing reestablishment of malaria transmission, finally benefit all individuals still suffering from the scourge of malaria.

BackgroundSulfadoxine-pyrimethamine (SP) is recommended for intermittent preventive treatment in Africa against Plasmodium falciparum infection. However, increasing SP resistance (SPR) of P. falciparum affects the therapeutic efficacy of SP, and pfdhfr (encoding dihydrofolate reductase) and pfdhps (encoding dihydropteroate synthase) genes are widely used as molecular markers for SPR surveillance. In the present study, we analyzed single nucleotide polymorphisms (SNPs) of pfdhfr and pfdhps in P. falciparum isolated from infected Chinese migrant workers returning from Africa.MethodsIn total, 159 blood samples from P. falciparum-infected workers who had returned from Africa to Anhui, Shangdong, and Guangxi provinces were successfully detected and analyzed from 2017 to 2019. The SNPs in pfdhfr and pfdhps were analyzed using nested PCR. The genotypes and linkage disequilibrium (LD) were analyzed using Haploview.ResultsHigh frequencies of the Asn51Ile (N51I), Cys59Arg(C59R), and Ser108Asn(S108N) mutant alleles were observed, with mutation frequencies of 97.60, 87.43, and 97.01% in pfdhfr, respectively. A triple mutation (IRN) in pfdhfr was the most prevalent haplotype (86.83%). Six point mutations were detected in pfdhps DNA fragment, Ile431Val (I431V), Ser436Ala (S436A), Ala437Gly (A437G), Lys540Glu(K540E), Ala581Gly(A581G), Ala613Ser(A613S). The pfdhps K540E (27.67%) was the most predominant allele, followed by S436A (27.04%), and a single mutant haplotype (SGKAA; 62.66%) was predominant in pfdhps. In total, 5 haplotypes of the pfdhfr gene and 13 haplotypes of the pfdhps gene were identified. A total of 130 isolates with 12 unique haplotypes were found in the pfdhfr-pfdhps combined haplotypes, most of them (n = 85, 65.38%) carried quadruple allele combinations (CIRNI-SGKAA).ConclusionA high prevalence of point mutations in the pfdhfr and pfdhps genes of P. falciparum isolates was detected among Chinese migrant workers returning from Africa. Therefore, continuous in vitro molecular monitoring of Sulfadoxine-Pyrimethemine combined in vivo therapeutic monitoring of artemisinin combination therapy (ACT) efficacy and additional control efforts among migrant workers are urgently needed.

Background/Aims: This study aims to predict the pro-angiogenic functions of monocytic-type myeloid-derived suppressor cells (M-MDSCs) derived from mice infected with Echinococcus granulosus. Methods: M-MDSCs were collected from Balb/c mice infected with E. granulosus and normal mice (control) and cultured in vitro. Human umbilical vein endothelial cells (HUVECs) were stimulated with the cell supernatant, and angiogenesis was investigated and analysed by the Angiogenesis module of the software NIH Image J. RNA was extracted from fresh isolated M-MDSCs and analysed with miRNA microarray; differentially expressed miRNAs and their potential functions were analysed through several bioinformatics tools. Finally, quantitative PCR was used to confirm the results of microarray analysis. Results: M-MDSCs from mice infected with E. granulosus could promote the formation of tubes from HUVECs in vitro. Moreover, vascular endothelial growth factor (VEGF) showed significantly high expression, whereas soluble fms-like tyrosine kinase-1 (sFlt-1) showed low expression at the transcriptional level in M-MDSCs from mice infected with E. granulosus. Microarray analysis of miRNAs showed that 28 miRNAs were differentially expressed in M-MDSCs from the two experimental mice groups, and 272 target genes were predicted using the microRNA databases TargetScan, PITA and microRNAorg. These target genes were mainly involved in the biological processes of intracellular protein transport, protein targeting to the lysosome and protein transport, and mainly located in the cytoplasm, neuronal cell body and membrane. Moreover, they were mainly involved in the molecular functions of protein binding, metal ion binding and SH3 domain binding. Further, the differentially expressed miRNAs were mainly enriched in the endocytosis, Wnt and axon guidance pathways, as well as the MAPK, focal adhesion, PI3K-Akt, cAMP, mTOR and TGF-β signalling pathways, which are linked to immunoregulation and angiogenesis based on the results of bioinformatics analysis with DIANA-miRPath 3.0. In addition, the expression of eight miRNAs was randomly verified by quantitative PCR independently in three mice infected with E. granulosus and three normal mice. Conclusion: M-MDSCs have a potential angiogenic role during E. granulosus infection, and miRNAs may play a role in the immune response and angiogenesis functions of M-MDSCs through regulation of the identified signalling pathways.

Abstract Background Malaria was once one of the most serious public health problems in China. However, the disease burden has sharply declined and epidemic areas have shrunk after the implementation of an integrated malaria control and elimination strategy, especially since 2000. In this review, the lessons were distilled from the Chinese national malaria elimination programme and further efforts to mitigate the challenges of malaria resurgence are being discussed. Methods A retrospective evaluation was performed to assess the changes in malaria epidemic patterns from 1950 to 2017 at national level. The malaria data before 2004 were collected from paper-based annual reports. After 2004, each of the different cases from the Infectious Diseases Information Reporting Management System (IDIRMS) was closely examined and scrutinized. An additional documenting system, the National Information Management System for Malaria, established in 2012 to document the interventions of three parasitic diseases, was also examined to complete the missing data from IDIRMS. Results From 1950 to 2017, the occurrence of indigenous malaria has been steeply reduced, and malaria-epidemic regions have substantially shrunk, especially after the launch of the national malaria elimination programme. There were approximately 30 million malaria cases annually before 1949 with a mortality rate of 1%. A total of 5999 indigenous cases were documented from 2010 to 2016, with a drastic reduction of 99% over the 6 years (2010, n = 4262; 2016, n = 3). There were indigenous cases reported in 303 counties from 18 provinces in 2010, but only 3 indigenous cases were reported in 2 provinces nationwide in 2016. While in 2017, for the first time, zero indigenous case was reported in China, and only 7 of imported cases were in individuals who died of Plasmodium falciparum infection. Conclusion Malaria elimination in China is a country-led and country-owned endeavour. The country-own efforts were a clear national elimination strategy, supported by two systems, namely a case-based surveillance and response system and reference laboratory system. The country-led efforts were regional and inter-sectoral collaboration as well as sustained monitoring and evaluation. However, there are still some challenges, such as the maintenance of non-transmission status, the implementation of a qualified verification and assessment system, and the management of imported cases in border areas, through regional cooperation. The findings from this review can probably help improving malaria surveillance systems in China, but also in other elimination countries.

Abstract Background Excretory-secretory products (ESPs) released by helminths are well-known to regulate T cell responses in the host. However, their direct influence in the differentiation of naïve T cells, and especially B cells, remains largely unknown. This study investigated the effects of Echinococcus granulosus protoscoleces ESPs (EgPSC-ESPs) on the differentiation of IL-10-producing B cells (B10), IL-17A-producing B cells (B17) and Th17 cells. Methods BALB/c mice injected with EgPSC were used to evaluate the in vivo profiles of B10, B17 and Th17 cells. In vitro purified CD19+ B and naïve CD4+ T cells were cultured in the presence of native, heat-inactivated or periodate-treated EgPSC-ESPs, and the differentiation of these cell subsets were compared. Results In contrast to the control group, infected mice showed higher frequencies of B10, B17 and Th17 cells, and higher levels of IL-10 and IL-17A in the sera. Interestingly, B17 cells were first identified to express CD19+CD1dhigh. In vitro, B cells cultured with native ESPs exhibited a higher percentage of B10 cells but lower percentage of B17 and Th17 cells compared to the PBS group. Moreover, the relative expression of IL-10 and IL-17A mRNA were consistent with the altered frequencies. However, ESPs subjected to heat-inactivation or periodate treatment exhibited an inverse effect on the induction of these cell subsets. Conclusions Our findings indicate that ESPs released by EgPSC can directly regulate the differentiation of B10, B17 and Th17 cells, which appear to be heat-labile and carbohydrate-dependent.

Abstract Background Cystic echinococcosis is a serious zoonotic infection worldwide caused by metacestodes of Echinococcus gruanulosus. Mebendazole and albendazole are the only two drugs used in the treatment of this disease with cure rates only about 30% due to the poor oral absorption. Thus an alternative treatment for this disease is needed. Methods A mebendazole oily suspension (MBZ-OS) was prepared and orally administrated to mice infected with echinococcus cysts for 8 months at 12.5 mg/kg and 25 mg/kg for 14 consecutive days. Mebendazole suspended in 1% tragacanth (MBZ-1% tragacanth) served as treated control. In addition, liver and serum samples were collected from these treated mice (25 mg/kg) for histopathology examination and liver function test. For pharmacokinetic analysis, plasma, parasite (cyst wall and cyst fluid) and tissue samples were collected at 0.25, 0.5, 1, 2, 4, 8, 16 and 24 h after orally administrating MBZ-OS and MBZ-1% tragacanth to E. granulosus-infected mice at 25 mg/kg. These samples were then processed and quantitatively analyzed by HPLC. Results The administration of MBZ-OS resulted in a treatment efficacy with the cyst weight reductions higher than 80%, significantly better than the corresponding MBZ-1% tragacanth groups. The better treatment efficacy of MBZ-OS was related to the higher drug concentration in plasma, parasites and tissues. It was also shown that the injury of the liver was not significantly altered by taking MBZ-OS compared to the untreated control. Conclusion These findings demonstrate that MBZ-OS is a promising new formulation of MBZ for treatment of hydatid diseases without showing significantly liver toxicity.

BACKGROUND: Towards the implementation of national malaria elimination programme in China since 2010, the epidemiology of malaria has changed dramatically, and the lowest malaria burden was achieved yearly. It is time to analyze the changes of malaria situation based on surveillance data from 2010 to 2012 to reconsider the strategies for malaria elimination. METHODS AND PRINCIPAL FINDINGS: Malaria epidemiological data was extracted from the provincial annual reports in China between 2010 and 2012. The trends of the general, autochthonous and imported malaria were analyzed, and epidemic areas were reclassified according to Action Plan of China Malaria Elimination (2010-2020). As a result, there reported 2743 malaria cases with a continued decline in 2012, and around 7% autochthonous malaria cases accounted. Three hundred and fifty-three individual counties from 19 provincial regions had autochthonous malaria between 2010 and 2012, and only one county was reclassified into Type I (local infections detected in 3 consecutive years and the annual incidences ≥ 1/10,000) again. However, the imported malaria cases reported of each year were widespread, and 598 counties in 29 provinces were suffered in 2012. CONCLUSIONS/SIGNIFICANCE: Malaria was reduced significantly from 2010 to 2012 in China, and malaria importation became an increasing challenge. It is necessary to adjust or update the interventions for subsequent malaria elimination planning and resource allocation.

Background: In China, the prevalence of malaria has reduced dramatically due to the elimination programme. The continued success of the programme will depend upon the accurate diagnosis of the disease in the laboratory. The basic requirements for this are a reliable malaria diagnosis laboratory network and quality management system to support case verification and source tracking. Methods: The baseline information of provincial malaria laboratories in the China malaria diagnosis reference laboratory network was collected and analysed, and a quality-assurance activity was carried out to assess their accuracies in malaria diagnosis by microscopy using WHO standards and PCR. Results: By the end of 2013, nineteen of 24 provincial laboratories have been included in the network. In the study, a total of 168 staff were registered and there was no bias in their age, gender, education level, and position. Generally Plasmodium species were identified with great accuracy by microscopy and PCR. However, Plasmodium ovale was likely to be misdiagnosed as Plasmodium vivax by microscopy. Conclusions: China has established a laboratory network for primary malaria diagnosis which will cover a larger area. Currently, Plasmodium species can be identified fairly accurately by microscopy and PCR. However, laboratory staff need additional trainings on accurate identification of P. ovale microscopically and good performance of PCR operations. [ABSTRACT FROM AUTHOR]

The historical patterns of malaria transmission in the People's Republic of China from 1949 to 2010 are presented in this chapter to illustrate the changes in epidemiological features and malaria burden during five decades. A significant reduction of malaria incidence has resulted in initiation of a national malaria elimination programme. However, challenges in malaria elimination have been identified. Foci (or hot spots) have occurred in unstable transmission areas, indicating an urgent need for strengthened surveillance and response in the transition stage from control to elimination. [ABSTRACT FROM AUTHOR]

Background: In the battle against malaria in China, the rate of elementary and high school students' awareness on malaria knowledge is an important index for malaria elimination, but only rare data is available. This study aimed to investigate the level of malaria awareness in students at elementary and high schools in malaria endemic areas of China, and to provide the baseline information for the malaria elimination. Methods: This cross-sectional survey was conducted in 20 different malaria-endemic provinces in the first year of China's National Malaria Elimination Programme (NMEP). A structured questionnaire was administrated to students at elementary and high schools enrolled. A total of 44,519 questionnaires were effective while 1,220 were excluded because of incomplete survey responses. Results: More than 60% of students were aware of malaria, but only 9,013 of them answered correctly to all five questions, and there were still 1,862 students unaware of malaria. There were significant differences of the awareness of malaria among different age groups, between male and female, between two different education levels. Discussion: The study reveals that students at elementary and high school levels did not have adequate knowledge of malaria about biology, pathogenicity, transmitting vectors and preventive methods and so on at the beginning of NMEP in China. Further emphasis should be paid on health education campaigns in China to increase students' public awareness of malaria about vector control, treatment, prevention. [ABSTRACT FROM AUTHOR]

Objective: To compare the performance of modified Kato-Katz thick smear method (KK method) and PCR assay in field detection of Clonorchis sinensis in human fecal samples, which provides insight into the selection of tools for detecting C. sinensis ., Methods: Based on the epidemiological investigation of human C. sinensis infections in Tengxian County of Guangxi Zhuang Autonomous Region in 2016, a total of 133 fecal samples were randomly selected and stored at -20 ℃. All fecal samples were detected for C. sinensis infection using KK method and PCR assay, and the detection rate was compared between the two techniques. In addition, Kappa test was used to evaluate the consistency between the two methods., Results: Among all fecal samples, the overall detection rate of C. sinensis was 77.44% (103/133), and the detection rate was significantly higher by PCR assay (70.68%, 93/133) than by KK method (57.14%, 76/133) ( χ 2 = 26.15, P < 0.01). There were 88.16% (67/76) of the microscopy-positive fecal samples positive for PCR assay, and 47.37% (27/57) of the microscopy-negative fecal samples positive for PCR assay. The detection rate of C. sinensis by PCR assay (94.74%, 18/19) was higher in fecal samples with EPG of > 1 000 than in samples with EPG of < 1 000 (85.96%, 49/57) ( χ 2 = 1.05, P = 0.436). The consistency of the detection rate of C. sinensis was moderate between the KK method and PCR assay ( Kappa = 0.73)., Conclusions: The detection rate of C. sinensis by PCR assay is significantly higher than by KK method. In low-endemic areas of C. sinensis infections, the combination of KK method and PCR assay is suggested, so as to improve the detection rate.

Objective: To compare the genetic diversity of imported Plasmodium falciparum by Polyα and TAA87 microsatellite markers in Southeast Asian and African geographical isolates., Methods: Ninety-two and 126 filter paper samples from patients infected with P. falciparum from Southeast Asia (Myanmar) and Africa (Ghana) were collected, respectively. Two neutral microsatellite loci, Polyα and TAA87 were amplified by PCR. The length of PCR fragments was detected by capillary electrophoresis. The allele frequency and expected heterozygosity ( H e) were calculated by Excel 2010 and GenALEx 6.0 software., Results: A total of 146 P. falciparum samples were analyzed as single infection samples with a total of 26 alleles in locus Polyα and 12 alleles in locus TAA87. The mean H e value of the two loci was 0.86 ± 0.02. Ten alleles in locus Polyα and 8 alleles in locus TAA87 were distributed in Myanmar isolates, with the H e values of 0.86 and 0.81 respectively. Fifteen alleles in locus Polyα and 11 in locus TAA87 were detected in Ghana isolates, with the H e values of 0.91 and 0.86 respectively. In addition, the haplotype of 174 bp (Polyα) and 113 bp (TAA87) were only detected in Myanmar isolates with more than 17% gene frequency, whereas they were absent in Ghana isolates., Conclusions: The two different geographical sources of imported P. falciparum strains have different allele frequencies and haplotypes at the two neutral microsatellite markers, Polyα and TAA87. Therefore, these two microsatellite loci may be considered as the potential molecular marker candidates for identifying P. falciparum strains with different geographical sources.

Objective: To preliminarily study the pro-angiogenic activity of Echinococcus granulosus hydatid cysts against human umbilical vein endothelial cells in vitro and the transcriptional level of potential pro-angiogenic factors., Methods: The hydatid cysts and protoscolex derived from experimentally infected mice were collected and cultured in vitro , then the human umbilical vein endothelial cells were stimulated by the supernatant and cyst fluid respectively, and the angiogenesis was observed and analyzed through a microscope and the angiogenesis mode of the software NIH Image J. Meanwhile, the mouse homologous proteins of matrix metalloproteinase-9 (MMP-9) and high mobility group box B1 (HMGB1) were identified in E. granulosus genome through sequence alignment, and their transcriptional levels in the cyst wall and protoscolex were analyzed., Results: The culture supernatant of hydatid cysts significantly promoted human umbilical vein endothelial cells into tubes ( F = 73.03, P < 0.001), the transcriptions of MMP-9 and HMGB1 were detected in the cyst wall and protoscolex, and the transcriptional level of MMP-9 was higher in protoscolex ( t = -11.65, P < 0.001), while the level of HMGB1 was higher in hydatid cysts ( t = 6.43, P = 0.003)., Conclusions: Some parasite-derived pro-angiogenic molecules may exist in the supernatant of E. granulosus hydatid cysts, while further researches are required into their exact mechanisms.