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Microscopy is the gold standard for parasitological confirmation, but the accuracy of microscopic diagnosis is influenced by the skill of the technicians. An alternative is the immunologic-based malaria rapid diagnostic tests (mRDTs).Our study evaluated standard microscopy in health system (SMHS) and mRDTs for focused screening and treatment of malaria (FSAT) in Southern Tanzania. We showed that mRDTs were more sensitive than local SMHS for diagnosing malaria infection.Malaria rapid diagnostic tests can be useful as an alternative to SMHS for FSAT in the local context of Tanzania.

Purpose We previously found that human cytomegalovirus (HCMV) infection is associated with gastric cancer (GC) development. UL111A plays a role during HCMV productive or latent infection. However, UL111A expression profiles in GC tissues and their relationship with this disease are unknown. Methods PCR and nested RT-PCR were performed to verify UL111A expression in 71 GC tissues and its transcripts in 16 UL111A-positive GC samples. UL111A expression levels in GC patients were evaluated by immunohistochemistry on a tissue microarray for 620 GC patients. The correlations among UL111A expression levels, clinicopathological characteristics, and prognosis were analyzed. Further, the effects of overexpression of latency-associated viral interleukin-10 (LAcmvIL-10) and cmvIL-10 on GC cell proliferation, colony formation, migration, and invasion were assessed. Results The UL111A detection rate in GC tissues was 32.4% (23/71) and that of its mRNA expression was 68.75% (11/16). High expression of UL111A was also related to better overall and disease-free survival in GC patients. GC patients with TNM II/III stage expressing higher UL111A levels might benefit from adjuvant chemotherapy (ACT) after surgery. Moreover, high UL111A expression was also associated with increased CD4+ , CD8+ T-lymphocyte and Foxp3+ T-cell infiltration. In vitro assays further demonstrated that LAcmvIL-10 and cmvIL-10 overexpression inhibits GC cell line proliferation, colony formation, migration, and invasion. Conclusions High UL111A expression changes the number of infiltrating T cells and is associated with favorable survival. Therefore, UL111A could be used as an independent prognostic biomarker and might be a potential therapeutic target for GC.

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.

BackgroundBorder malaria remain as one of the greatest challenges facing elimination in China. Malaria control interventions among migrant population across border relies on personal protection from mosquito bites. Understanding the knowledge of the link between mosquitoes and malaria will inform malaria control and elimination programmes on those targeted risk population.MethodsFrom March 2018 to September 2019, 108 migrant workers from Vietnam were enrolled conducted in Ning Ming County in Guangxi. Each people were interviewed using the structured questionnaires. Blood samples were collected and sent to the PCR detection and sequenced.ResultsMalaria knowledge was poor with 19.4% on transmission, 23.2% on clinical symptoms, 7.4% on awareness of the risk of death, and 14.8% on awareness of prevention methods. No significant difference was found among occupations except for migrant workers, whose knowledge rate were higher than other occupations. Most of the participants (80.6%) had mosquito nets and 73.2% of them had 2 persons who were under the bed net at night. The usage rate of bed-nets accounted for over 49.1%. For parasitological study, 5.6% (n = 6) of all participants infected tested positive for malaria, and no statistically significant differences in the positive rate among different age, sex, family size, nationality, occupation and different behaviors.ConclusionThe health education focus on the high risk population such as migrant workers and forest goers should be strengthened. Therefore, health education based on verbal communication such as web, radio, and mobile phone may be required under the COVID-19 pandemic situation. Further risk assessment of importation and proactive case detection should also be carried out, not only in Ningming County, but also in other border counties in Guangxi, which aimed to timely detect the patients, as well as the asymptomatic infections that could cause the re-establishment of malaria.

The artemisinin-based combination therapies (ACTs) used to treat Plasmodium falciparum in Africa are threatened by the emergence of parasites in Asia that carry variants of the Kelch 13 (K13) locus with delayed clearance in response to ACTs. Single nucleotide polymorphisms (SNPs) in other molecular markers, such as ap2mu and ubp1, were associated with artemisinin resistance in rodent malaria and clinical failure in African malaria patients. Here, we characterized the polymorphisms in pfmdr1, pfcrt, pfK13, pfubp1, and pfap2mu among African isolates reported in Shandong and Guangxi provinces in China. Among 144 patients with P. falciparum returning from Africa from 2014 to 2018, pfmdr1 N86Y (8.3%) and pfcrt K76T (2.1%) were the major mutant alleles. The most common genotype for pfcrt was I74E75T76 (8.3%), followed by E75T76 (2.1%). For K13 polymorphisms, a limited number of mutated alleles were observed, and A578S was the most frequently detected allele in 3 isolates (2.1%). A total of 27.1% (20/144) of the isolates were found to contain pfubp1 mutations, including 6 nonsynonymous and 2 synonymous mutations. The pfubp1 genotypes associated with artemisinin resistance were D1525E (10.4%) and E1528D (8.3%). Furthermore, 11 SNPs were identified in pfap2mu, and S160N was the major polymorphism (4.2%). Additionally, 4 different types of insertions were found in pfap2mu, and the codon AAT, encoding aspartic acid, was more frequently observed at codons 226 (18.8%) and 326 (10.7%). Moreover, 4 different types of insertions were observed in pfubp1 at codon 1520, which was the most common (6.3%). These findings indicate a certain degree of variation in other potential molecular markers, such as pfubp1 and pfap2mu, and their roles in either the parasite's mechanism of resistance or the mode of action should be evaluated or elucidated further.

The artemisinin-based combination therapies (ACTs) used to treat Plasmodium falciparum in Africa are threatened by the emergence of parasites in Asia that carry variants of the Kelch 13 (K13) locus with delayed clearance in response to ACTs. Single nucleotide polymorphisms (SNPs) in other molecular markers, such as ap2mu and ubp1, were associated with artemisinin resistance in rodent malaria and clinical failure in African malaria patients. Here, we characterized the polymorphisms in pfmdr1, pfcrt, pfK13, pfubp1, and pfap2mu among African isolates reported in Shandong and Guangxi provinces in China. Among 144 patients with P. falciparum returning from Africa from 2014 to 2018, pfmdr1 N86Y (8.3%) and pfcrt K76T (2.1%) were the major mutant alleles. The most common genotype for pfcrt was I(74)E(75)T(76) (8.3%), followed by E(75)T(76) (2.1%). For K13 polymorphisms, a limited number of mutated alleles were observed, and A578S was the most frequently detected allele in 3 isolates (2.1%). A total of 27.1% (20/144) of the isolates were found to contain pfubp1 mutations, including 6 nonsynonymous and 2 synonymous mutations. The pfubp1 genotypes associated with artemisinin resistance were D1525E (10.4%) and E1528D (8.3%). Furthermore, 11 SNPs were identified in pfap2mu, and S160N was the major polymorphism (4.2%). Additionally, 4 different types of insertions were found in pfap2mu, and the codon AAT, encoding aspartic acid, was more frequently observed at codons 226 (18.8%) and 326 (10.7%). Moreover, 4 different types of insertions were observed in pfubp1 at codon 1520, which was the most common (6.3%). These findings indicate a certain degree of variation in other potential molecular markers, such as pfubp1 and pfap2mu, and their roles in either the parasite’s mechanism of resistance or the mode of action should be evaluated or elucidated further.

Eliminating malaria along the China-Vietnam border remains one of the greatest challenges in China, especially during the coronavirus disease 2019 (COVID-19) pandemic, which has disrupted the continuity of malaria control and elimination programs. Understanding the factors associated with asymptomatic malaria infection will inform control interventions aimed at elimination of the disease among migrants from Vietnam working in China, who constitute an at-risk population.From March 2018 to September 2019, 108 migrants from Vietnam working in Ningming County, Guangxi, were enrolled in this study. Each person was interviewed using a structured questionnaire. Blood samples were collected and sent for PCR detection and sequencing. The obtained sequences were analyzed using the BLAST program and DNAMAN software.The proportion of participants with malaria knowledge was low, with 19.4% (21/108) reporting knowledge about transmission, 23.2% (25/108) reporting knowledge about clinical symptoms, 7.4% (8/108) reporting awareness of the risk of death and 14.8% (16/108) reporting awareness of prevention methods. No significant difference in the malaria knowledge rate was found among occupational groups, except in the migrant worker group, whose knowledge rate was higher than those in the other occupational groups (χHealth education focused on high-risk populations, such as migrant workers and forest goers, should be strengthened. Verbal communication and information transmission via the internet, radio, and mobile phone platforms may be required during the COVID-19 pandemic. Further risk assessments and proactive case detection should also be performed in Ningming County and other border counties in Guangxi to detect active and asymptomatic infections in a timely manner and prevent re-establishment of the disease in these communities.

What is already known on this topic? Imported malaria cases endanger people’s health and potentially cause local re-transmission, and they may also cause economic loss on patients’ families and society as a whole. What is added by this report? This is the first report to focus on the disease burden of a case study incurred by the imported malaria. The results indicated that the median direct medical cost was 2,904.4 CNY and the median indirect cost was 242.0 CNY for a patient’s hospitalization. The economic cost was related to age, time between onset and diagnosis, and days of stay in hospital. What are the implications for public health practice? This study analyzed the main causes based on both direct and indirect economic loss of imported malaria cases to provide general information for the evaluation of the disease burden of imported malaria patients and shed light on the rational allocation of medical resources.

BackgroundIn 2015, a China-UK-Tanzania tripartite pilot project was implemented in southeastern Tanzania to explore a new model for reducing malaria burden and possibly scaling-out the approach into other malaria-endemic countries. The 1,7-malaria Reactive Community-based Testing and Response (1,7-mRCTR) which is a locally-tailored approach for reporting febrile malaria cases in endemic villages was developed to stop transmission andPlasmodiumlife-cycle. The (1,7-mRCTR) utilizes existing health facility data and locally trained community health workers to conduct community-level testing and treatment.MethodsThe pilot project was implemented from September 2015 to June 2018 in Rufiji District, southern Tanzania. The study took place in four wards, two with low incidence and two with a higher incidence. One ward of each type was selected for each of the control and intervention arms. The control wards implemented the existing Ministry of Health programmes. The 1,7-mRCTR activities implemented in the intervention arm included community testing and treatment of malaria infection. Malaria case-to-suspect ratios at health facilities (HF) were aggregated by villages, weekly to identify the village with the highest ratio. Community-based mobile test stations (cMTS) were used for conducting mass testing and treatment. Baseline (pre) and endline (post) household surveys were done in the control and intervention wards to assess the change in malaria prevalence measured by the interaction term of ‘time’ (post vs pre) and arm in a logistic model. A secondary analysis also studied the malaria incidence reported at the HFs during the intervention.ResultsOverall the 85 rounds of 1,7-mRCTR conducted in the intervention wards significantly reduced the odds of malaria infection by 66% (adjusted OR 0.34, 95% CI 0.26,0.44, p ConclusionThe 1,7-mRCTR approach significantly reduced the malaria burden in the areas of high transmission in rural southern Tanzania. This locally tailored approach could accelerate malaria control and elimination efforts. The results provide the impetus for further evaluation of the effectiveness and scaling up of this approach in other high malaria burden countries in Africa, including Tanzania.

Additional file 1: Survey organization and Implementation.

Background: In 2015, a China-UK-Tanzania tripartite pilot project was implemented in south-eastern Tanzania to explore a new model to reduce the malaria burden with the aim of eventually scaling-up the approach in Africa. Chinese and Tanzanian teams have developed a locally-tailored malaria control approach screening for febrile cases in endemic villages on Day 1 followed by focal treatment of holoendemic villages within 7 days to stop transmission at the same phase of the plasmodium life-cycle. This 1,7-Reactive Community-based Testing and Response (1,7-mRCT) model can utilize existing health facility data and locally trained community-based health workers to conduct community-level testing and treatment. Methods: Matched malaria incidence pairs of control and intervention wards were chosen. The latter arm was selected for the 1,7-mRCT approach, while the control wards relied on long-lasting insecticide-treated bednets only. The 1,7-mRCT activities included community testing and treatment of malaria infection. Case-to-suspect ratios of malaria cases were aggregated at the village level weekly to identify the village with the highest ratio. Community-based mobile test stations (cMTS) were used for mass testing and treatment. The pilot project was implemented from September 2015 to June 2018 with 85 rounds of 1,7-mRCT implemented in the intervention wards. Comparing the two arms of approach we look for any change in malaria prevalence from the baseline to the endline survey. Besides we also studied the malaria incidence reported at the health facilities after interventions in the treated villages. Findings: Compared to the control wards, the 1,7-mRCT model significantly reduced the malaria infections by 66% (adjusted OR 0.34, 95%CI 0.26-0.44, p

Additional file 2: Analytical procedure for HFs data.

Background The resistance of Plasmodium falciparum to artemisinin has been identified in Asia and some parts of Africa. The drug resistance of P. falciparum will be an obstacle to the successful elimination of malaria by 2025. Whole-genome sequencing of the artemisinin-resistant parasite line revealed mutations on the k13 gene associated with drug resistance in P. falciparum. To understand the artemisinin resistance of the imported P. falciparum cases from Africa, the mutations in the k13 gene in parasites from imported malaria cases in Guangxi Province were detected and the treatment efficiency of artesunate monotherapy was observed. Methods DNA was extracted from 319 blood samples from migrant workers with P. falciparum infection who returned to their hometown in Guangxi Province from Africa between 2014 and 2017. The k13-propeller gene was amplified by nested PCR, and sequencing, gene mutation frequency and geographic difference of imported P. falciparum cases were analysed by comparison with the wild-type strain. Of 319 patients, 158 were P. falciparum-infected and were treated with intravenous injection of artesunate and were observed, including the time of asexual stage clearance and the dose of artesunate used. Results Of the 319 P. falciparum samples, 12 samples had the k13-propeller mutation, and 11 point mutations were detected; 5 were non-synonymous mutations (T474I, A481T, A578S, V603E, G665S) and were not associated with artemisinin resistance. The clinical treatment observation showed that the median (IQR) dose of artesunate for peripheral blood parasite asexual stage clearance was 407.55 (360–510) mg, and the D3 parasite clearance rate was 70.25%, including the five k13-propeller mutations of P. falciparum. After 7 days of treatment, 98.73% of cases were cleared. Two cases were treated with artemisinin for 8 days with a 960-mg dose to completely clear the asexual parasite, but they did not have a mutation in the k13 gene. Conclusions Five mutations of the k13-propeller gene in 319 P. falciparum samples from patients returning from Africa were identified. The frequency of the k13-propeller mutants was low, and the mutations were not strongly associated with artemisinin resistance. The median (IQR) dose of artesunate monotherapy in actual clinical treatment to remove asexual parasite stages was 407.55 (360–510) mg, equivalent to D3–D4. Some P. falciparum cases without a k13-propeller mutation showed obvious delayed clearance of the parasite from peripheral blood. Trial registration The diagnosis of malaria and the treatment of malaria-infected patients are the routine work of Centres for Disease Control and Prevention. Information on the patients was conveyed with the patient’s approval, and the research aim, methods, risks and benefits of the study were explained in detail to the patients

Background: Gastric cancer (GC) is the fifth most common cancer worldwide. Tumor-infiltrating lymphocytes (TILs) are associated with development and progression of GC, and maybe a prognostic biomarker. Methods: We determined the expression of CD3+, CD4+, CD8+, CD20+, CD57+, and Foxp3+ TILs in tissue microarrays of 475 GC tissues by immunohistochemistry. Lymphocyte features and their ratios were used to build a multimarker TIL-Score by LASSO logistic regression. Chi-square tests and Kaplan-Meier estimation was performed to validate the efficiency of the TIL-Score for predicting GC prognosis. A nomogram and decision curve were prepared for guiding clinical decisions. Finding: Ten individual TIL factors were integrated into the TIL-Score by LASSO logistic regression. The clinicopathological analysis showed that the TIL-Score was correlated with tumor size, tumor invasion, lymph node metastasis, and lower TNM stage in the primary and validation cohorts. Patients in the high TIL-Score group had significantly higher overall survival and disease-free survival rates than patients in the low TIL-Score group in both the primary and validation cohorts. In the TIL nomogram based on independent prognostic factors, receiver operating characteristic analysis showed that the area under the curve values were 0.825 and 0.800 in the primary and validation cohorts, respectively. Decision curve analysis demonstrated that the TIL nomogram was clinically useful. Interpretation: Overall, we developed a multimarker TIL-Score and TIL nomogram useful for predicting the prognosis of patients with GC. Funding Statement: National Natural Science Foundation of China(31670922, 81672707 and 81602165), Natural Science Foundation of Zhejiang(YLQ16H190003), Wenzhou Science and Technology Bureau(Y2017002). Declaration of Interests: The authors report no conflict of interest. Ethics Approval Statement: The study was approved by the Research Ethics Committee of The Second Affiliated Hospital of Wenzhou Medical University. All subjects provided written informed consent.

Background During the past six decades, remarkable success on malaria control has been made in China. The major experience could be shared with other malaria endemic countries including Tanzania with high malaria burden. Especially, China’s 1–3-7 model for malaria elimination is one of the most important refined experiences from many years’ efforts and key innovation measures for malaria elimination in China. Methods The China-UK-Tanzania pilot project on malaria control was implemented from April, 2015 to June, 2018, which was an operational research with two communities receiving the proposed interventions and two comparable communities serving as control sites. The World Health Organization “Test, Treat, Track” (WHO-T3) Initiative, which calls for every suspected case to receive a diagnostic test, every confirmed case to be treated, and for the disease to be tracked, was integrated with Chinese experiences on malaria control and elimination for exploration of a proper model tailored to the local settings. Application of China’s 1–3-7 model integrating with WHO-T3 initiative and local resources aiming at reducing the burden of malaria in terms of morbidity and mortality by 30% in the intervention communities in comparison with that at the baseline survey. Discussion The China-UK-Tanzania pilot project on malaria control was that at China's first pilot project on malaria control in Africa, exploring the feasibility of Chinese experiences by China-Africa collaboration, which is expected that the strategies and approaches used in this project could be potential for scaling up in Tanzania and African countries, and contribute to the acceleration of malaria control and elimination in Africa. Electronic supplementary material The online version of this article (10.1186/s40249-018-0507-3) contains supplementary material, which is available to authorized users.

Objectives: In this study, we aimed to analyse the genetic diversity Kelch 13 (K13) propeller allele of the Plasmodium falciparum isolates mainly imported from Southeast Asia and Africa in southern China, including the provinces of Yunnan and Guangxi. Methods: At enrolment, we collected blood samples from patients with confirmed cases of malaria infection between January 2012 and December 2017, for analysis. Individual patient information was obtained via a malaria surveillance system. The malaria infections and P. falciparum K13 mutations were diagnosed by using a nested polymerase chain reaction (PCR) method. Results: The K13 mutations were identified in 283 P. falciparum isolates from 18 counties in Yunnan and 22 counties in Guangxi. Of Forty-six isolates (46/283, 16.3%) that harbored K13 mutant alleles were detected: 26.8% in Yunnan (33/123) and 8.1% in Guangxi (13/160). A total of 18 different K13 mutations were detected. Only the F446I mutation was detected in Yunnan isolates, and F446I was more frequent (20/46, 43.5%) than other alleles. Further, the temporal distribution of the F446I mutation ratio from 2012 to 2015 exhibited no significant difference in Yunnan Province (2012, 2/13, 15.4%; 2013, 7/40, 17.5%; 2014, 7/33, 21.2%; 2015, 4/37, 10.8%, p = 0.121). A578S allele was the main K13 mutation (5/283, 1.8%) from Africa. The K13 mutants were present in 33.3% of indigenous isolates, 27.4% of isolates from Southeast Asia, and 7.9% of isolates from Africa. The analysis of 10 neutral microsatellite loci of 60 isolates showed that at the TAA109 locus, the expected heterozygosity of F446I (He = 0.112 ± 0.007) was much lower than that of wild type and other mutation types in Myanmar isolates. With respect to geographic distribution, TAA109 also exhibited a significant difference between isolates from Southeast Asia (He = 0.139 ± 0.012) and those from Africa (He = 0.603 ± 0.044). Conclusions: The present findings on the geographic diversity of K13 mutant alleles in P. falciparum may provide a basis for routine molecular surveillance and risk assessment, to monitor artemisinin resistance (ART) in China. Our results will be helpful for enriching the artemisinin resistance database in China during the elimination and post-elimination phases.

Background Malaria is one of the most serious vector-borne diseases in the world. Vector control is an important measure for malaria prevention and elimination. However, this strategy is under threat as disease vectors are developing resistance to insecticides. Therefore, it is important to monitor mechanisms responsible for insecticide resistance. In this study, the presence of G119S mutation in the acetyl cholinesterase-encoding gene (ace-1) was investigated in nine Anopheles sinensis populations sampled across Guangxi Zhuang Autonomous Region China. Methods PCR–RFLP (polymerase chain reaction-restriction fragment length polymorphism) method was used to genotype each individual adult of An. sinensis. Direct sequencing of PCR products was performed to verify the accuracy of PCR–RFLP genotyping result. Population genetics analysis was conducted using Genepop programme. Results The frequencies of susceptible homozygotes, heterozygotes and resistant homozygotes in the nine populations ranged between 0–0.296, 0.143–0.500 and 0.333–0.857, respectively. Overall, a high frequency (0.519–0.929) of mutant 119S allele was observed and the genotype frequency of the ace-1 gene of An. sinensis was at Hardy–Weinberg equilibrium in each of the nine examined populations. Conclusion The G119S mutation has become fixed and is widespread in An. sinensis field populations in Guangxi, China. These findings are useful in helping design strategies for An. sinensis control.

During May-August 2013, a malaria outbreak comprising 874 persons in Shanglin County, China, was detected among 4,052 persons returning from overseas. Ghana was the predominant destination country, and 92.3% of malarial infections occurred in gold miners. Preventive measures should be enhanced for persons in high-risk occupations traveling to malaria-endemic countries.