Competency of malaria laboratory diagnosis at national and provincial levels at the beginning of malaria post-elimination phase, China.

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.

Epidemiological characteristics of Plasmodium malariae malaria in China: a malaria that should not be neglected post elimination.

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 < 0.001), and there was no significant trend in the number of cases reported per month. Moreover, four kinds of P. malariae cases were classified, including 567 imported cases from 41 countries in 8 regions and distributed in 27 provinces (autonomous regions, municipalities) in China, six indigenous cases in a small outbreak in Hainan, seven recurrent cases in Guangdong and Shanghai, and one induced case in Shanghai, respectively. In addition, only 379 cases (65.2%) were diagnosed as malaria on the first visit (P < 0.001), and 413 cases (71.1%) were further confirmed as P. malariae cases (P = 0.002). Meanwhile, most cases sought healthcare first in the health facilities at the county and prefectural levels, but only 76.7% (161/210) and 73.7% (146/198) cases were diagnosed as malaria, and the accuracy of confirmed diagnosis as malaria cases infected with P. malariae was only 77.2% (156/202) and 69.9% (167/239) in these health facilities respectively. CONCLUSIONS: Even though malaria cases infected with P. malariae didn't account for a high proportion of reported malaria cases nationwide, the threat posed by widely distributed imported cases, a small number of indigenous cases, recurrent cases and induced case cannot be ignored in China. Therefore, it is necessary to raise awareness and improve the surveillance and response to the non-falciparum species such as P. malariae, and prevent the reestablishment of malaria transmission after elimination.

Imported malaria from land bordering countries in China: A challenge in preventing the reestablishment of malaria transmission.

OBJECTIVE: No indigenous malaria cases have been reported since 2017 in China, but a large number of imported cases are still reported every year, including those from the land bordering countries. To characterize their epidemiological profiles will provide evidence for the development of appropriate strategies to effectively address the challenges of border malaria in the post-elimination phase. METHODS: Individual-level data of imported malaria cases from the land bordering countries were collected from 2017 to 2021 in China via the web-based surveillance systems, and analyzed by SPSS, ArcGIS and WPS software, to explore their epidemiological profiles. RESULTS: A total of 1170 malaria cases imported into China from six of the fourteen land bordering countries were reported between 2017 and 2021 with a decline trend. Overall, cases were widely distributed in 31-97 counties from 11 to 21 provinces but mainly in Yunnan. Moreover, these imported cases were mainly infected with P. vivax (94.8%), and a total of 68 recurrent cases were reported in 6-14 counties from 4 to 8 provinces. In addition, nearly 57.1% of the total reported cases could seek healthcare within 2 days of getting sick, and 71.3% of the reported cases could be confirmed as malaria on the day they sought medical care. CONCLUSIONS: China still needs to attach great importance to the risk and challenge of the imported malaria from bordering countries particularly from Myanmar in preventing reestablishment of malaria transmission in the post-elimination phase. It is necessary not only to strengthen collaboration and cooperation with the bordering countries, but also coordinate multiple departments at home to improve malaria surveillance and response system and prevent the reestablishment of malaria transmission in China.

Evolution of anti-malaria policies and measures in P.R. China for achieving and sustaining malaria-free.

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.

Risks of and response to cluster outbreak of imported malaria during malaria post-elimination era in China / 中国热带医学

@#Abstract: Objective　To analyze the recent cluster outbreaks of imported malaria and explore the risks, challenges and countermeasures for dealing with such events during malaria post-elimination era of malaria, and to provide reference for effectively addressing the risks and consolidating the achievements of malaria elimination. Methods　The individual malaria case data from "The Information System for Infectious Disease Surveillance" and "The Information System For Parasitic Diseases Prevention And Control" were collected，and the diagnosis classification, infection source, time and space distribution of cases were analyzed. Results　From January 1 to August 11, 2022, a total of 429 malaria cases were reported nationwide, an 18.9% decrease compared to the same period last year (529 cases), all of which were imported cases. The overall weekly trend of the outbreak remained stable, but since Week 31 (July 25-31), there has been a significant increase in the number of cases, with a peak on August 5. From July 25 to August 11, 2022, a total of 162 malaria cases were reported nationwide, up 315.4% from 39 cases in the same period last year, accounting for 37.8% of the total cases up to August 11, 2022. The main source of imported infections was Guinea (95 cases, 58.6%), with most cases reported in Longgang District, Shenzhen City, Guangdong Province (30 cases), Shilin County, Kunming City, Yunnan Province (21 cases), Chaoyang District, Beijing (11 cases), and Xiaoshan District, Hangzhou City, Zhejiang Province (7 cases). Conclusions　Due to the concentration of returnees to China, several entry port cities simultaneously experienced cluster outbreaks of imported malaria, which brought immense pressure and challenges to local medical and health institutions. Health facilities at all levels need to maintain high vigilance and sensitivity, be well prepared, and avoid death and secondary transmission caused by imported cases.

A malaria-free China: global importance and key experience.

Malaria has a worldwide distribution and is the world's deadliest mosquito-borne disease. The goal of malaria elimination is also reflected in the United Nations Sustainable Development Goals and the Global Technical Strategy for Malaria 2016-2030 issued by the World Health Organization (WHO). China succeeded in its malaria elimination programme after being certified as malaria-free by the WHO on 30 June 2021. Therefore, we document some of the key lessons learnt in the course of the malaria elimination effort in China in this special volume, showing how different strategies made elimination feasible in different subregions of China with different epidemiological and socioeconomic characteristics, in order to present strong signals to other malaria-endemic countries that malaria elimination is feasible within one generation.

High Frequency Mutations in pfdhfr and pfdhps of Plasmodium falciparum in Response to Sulfadoxine-Pyrimethamine: A Cross-Sectional Survey in Returning Chinese Migrants From Africa.

Background: Sulfadoxine-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. Methods: In 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. Results: High 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). Conclusion: A 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.

Quantitative Microbial Risk Assessment of Cryptosporidium and Giardia in Public Drinking Water in China.

We aimed to assess the risks of Cryptosporidium and Giardia infections associated with drinking water for local residents, based on a quantitative microbial risk assessment, in three densely populated regions of China. In total, 45 source water samples and 45 treated water samples were collected from June to December 2014. Five Cryptosporidium-positive samples and 5 Giardia-positive samples were found. The annual probability of infection for individuals in Jintan (6.27 × 10 -4-2.05 × 10 -3 for Cryptosporidium and 7.18 × 10 -4-2.32 × 10 -3 for Giardia), Ezhou (6.27 × 10 -4-1.10 × 10 -2 for Cryptosporidium and 3.65 × 10 -4-1.20 × 10 -3 for Giardia), and Binyang (3.79 × 10 -4-1.25 × 10 -3 for Cryptosporidium) exceeded the tolerable risk of infection of 10 -4 set by the United States Environmental Protection Agency. Moreover, the corresponding disease burdens of cryptosporidiosis and giardiasis, due to direct drinking and residual water in these regions, exceeded the threshold of 10 -6 disability-adjusted life years per person per year set by the World Health Organization. These results provide insights into strategies to improve the safety of drinking water.

The efficacy of an alternative mebendazole formulation in mice infected with Echinococcus multilocularis.

This study was conducted to investigate the efficacy of a new formulation of MBZ oily suspension (MBZ-OS) in experimentally Echinococcus multilocularis-infected mice. MBZ-OS was prepared and administered to mice infected with E. multilocularis at 12.5 and 25 mg/kg for 14 consecutive days. Then, the cysts were collected, weighed and histologically examined. The results showed that the reduction rate of cyst weight induced by MBZ-OS at two doses was 95.23% and 92.67%, which was significantly higher than that of MBZ-1% tragacanth (positive control) at corresponding concentrations (87.41% and 69.47%), indicating that the treatment of alveolar echinococcosis at lower doses could be achieved by the use of MBZ-OS. This finding shows that MBZ-OS is also a promising formulation for alveolar echinococcosis as well as cystic echinococcosis and deserves to be investigated in clinical applications against echinococcosis.

Pro-Angiogenic Activity of Monocytic-Type Myeloid-Derived Suppressor Cells from Balb/C Mice Infected with Echinococcus Granulosus and the Regulatory Role of miRNAs.

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-ß 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.

Ready for malaria elimination: zero indigenous case reported in the People's Republic of China.

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.

The excretory-secretory products of Echinococcus granulosus protoscoleces directly regulate the differentiation of B10, B17 and Th17 cells.

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.

[Molecular characteristics and RNA interference efficiency of Schistosoma japonicum Sj79 gene].

OBJECTIVE: To study the structural features and characteristics of a novel gene Schistosoma japonicum 79 (Sj79), and observe its effect of RNA interference (RNAi) , so as to provide the experimental basis for its further function study and mechanism study of anti reproductive development of schistosome. METHODS: The gene structure and characteristics of Sj79 were analyzed by bioinformatics methods. Then the expressions of Sj79 messenger RNA (mRNA) during the different developmental stages of schistosome were analyzed and the effects of RNAi silencing were observed by the soaking method. The transcriptional levels of Sj79 after RNAi were detected by real time PCR. RESULTS: The open reading frame of Sj79 contained 696 base pairs with an exon structure. The gene had obvious stage specificity, and its transcriptional level in mature female worms was the highest. After soaking for 3 d, the Sj79 mRNA level [ (41.0 ± 12.3)%] in the siRNA-1 group with low dosage (20 nmol/L) was lower than that in the siRNA-NC group [(103.2 ± 14.4)%], the difference was statistically significant (t = 3.28,P < 0.05). When with high dosage (200 nmol/L), both the Sj79 mRNA levels in the siRNA-1 group [(15.8 ± 10.9)%] and siRNA-2 group [(11.1 ± 8.8)%] were significantly lower than that in the siRNA-NC group [(100.1 ± 6.3)%] (t = 13.44, 27.84, both P < 0.01). After soaking for 7 d, only the Sj79 mRNA levels in the siRNA-1 group [(43.4 ± 4.5)%] and siRNA-2 group [(62.5 ± 5.4)%] with low dosage were lower than that in the siRNA-NC group [(100.4 ± 5.2)%], and the differences had statistical significance (t = 8.33, 5.07, both P < 0.01). CONCLUSION: Through this study, we have improved the mRNA sequence and genomic information of Sj79 gene, and understood its structural features, as well as selected out two effect fragments siRNA-1 and siRNA-2, which will provide the basic evidences for the further study on egg laying interference of the female adult worm of schistosome in vitro.

Establishing a China malaria diagnosis reference laboratory network for malaria elimination.

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.

An alternative mebendazole formulation for cystic echinococcosis: the treatment efficacy, pharmacokinetics and safety in mice.

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.

Historical patterns of malaria transmission in China.

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.

Changing malaria transmission and implications in China towards National Malaria Elimination Programme between 2010 and 2012.

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.

Age-related infection with Cryptosporidium species and genotype in pigs in China.

OBJECTIVE: Pigs, as hosts of zoonotic Cryptosporidium species/genotypes, are domestic animals with public health significance. The present study was to characterize the infection rate and species/genotype of Cryptosporidium in pre-weaned and post-weaned pigs from Shanghai and Shaoxing, China. METHODS: A total of 208 fecal samples (42 from pre-weaned piglets, and 166 from post-weaned pigs) were examined by nested PCR of the 18S rRNA gene and analyzed by phylogenetic DNA fragment sequencing of secondary PCR products. RESULTS: Infection was detected in 79 samples (19/42 pre-weaned piglets, and 60/166 post-weaned pigs). C. suis (14/79) and Cryptosporidium pig genotype II (65/79) were identified; piglets were more susceptible to the former (13/14) and post-weaned pigs to the latter (59/65). CONCLUSION: Infection of Cryptosporidium spp. in pigs was age-specific; piglets were more susceptible to C. suis while pigs were more susceptible to Cryptosporidium pig genotype II. These findings combined with the isolation of the two Cryptosporidium from water suggest that pigs may be a source of zoonotic Cryptosporidium water pollution. Improvements in pig feeding practices, sewage discharge, feces disposal and field worker protection are therefore important to prevent potential public health problems.