Epidemiologic Analysis of Efforts to Achieve and Sustain Malaria Elimination along the China-Myanmar Border.

Malaria cases have dramatically declined in China along the Myanmar border, attributed mainly to adoption of the 1-3-7 surveillance and response approach. No indigenous cases have been reported in China since 2017. Counties in the middle and southern part of the border area have a higher risk for malaria importation and reestablishment after elimination.

Molecular surveillance of pfcrt, pfmdr1 and pfk13-propeller mutations in Plasmodium falciparum isolates imported from Africa to China.

BACKGROUND: The emergence and spread of multidrug resistance poses a significant risk to malaria control and eradication goals in the world. There has been no indigenous malaria cases reported in China since 2017, and China is approaching national malaria elimination. Therefore, anti-malarial drug resistance surveillance and tracking the emergence and spread of imported drug-resistant malaria cases will be necessary in a post-elimination phase in China. METHODS: Dried blood spots were obtained from Plasmodium falciparum-infected cases returned from Africa to China between 2012 and 2015, prior to anti-malarial drug treatment. Whole DNA were extracted and known polymorphisms relating to drug resistance of pfcrt, pfmdr1 gene, and the propeller domain of pfk13 were evaluated by nested PCR and sequencing. The haplotypes and prevalence of these three genes were evaluated separately. Chi-squared test and Fisher's exact test were used to evaluate differences among the different sub-regions of Africa. A P value < 0.05 was used to evaluate differences with statistical significance. The maps were created using ArcGIS. RESULTS: A total of 731 P. falciparum isolates were sequenced at the pfcrt locus. The wild type CVMNK was the most prevalent haplotype with prevalence of 62.8% and 29.8% of the isolates showed the triple mutant haplotype CVIET. A total of 434 P. falciparum isolates were successfully sequenced and pfmdr1 allelic variants were observed in only codons 86, 184 and 1246. Twelve haplotypes were identified and the prevalence of the wild type pfmdr1 NYD was 44.1%. The single mutant pfmdr1 in codons 86 and 184 was predominant but the haplotype NYY with single mutation in codon 1246 was not observed. The double mutant haplotype YFD was common in Africa. About 1,357 isolates were successfully sequenced of pfk13-propeller domain, the wild type was found in 1,308 samples (96.4%) whereby 49 samples (3.6%) had mutation in pfk13. Of 49 samples with pfk13 mutations, 22 non-synonymous and 4 synonymous polymorphic sites were confirmed. The A578S was the most common mutation in pfk13-propeller domain and three mutations associated with artemisinin resistance (M476I, R539T, P553L) were identified in three isolates. CONCLUSION: This study provides evidence that could give insight into potential issues with anti-malarial drug resistance to inform national drug policy in China in order to treat imported cases.

No evidence of amplified Plasmodium falciparum plasmepsin II gene copy number in an area with artemisinin-resistant malaria along the China-Myanmar border.

BACKGROUND: The emergence and spread of artemisinin resistance in Plasmodium falciparum poses a threat to malaria eradication, including China's plan to eliminate malaria by 2020. Piperaquine (PPQ) resistance has emerged in Cambodia, compromising an important partner drug that is widely used in China in the form of dihydroartemisinin (DHA)-PPQ. Several mutations in a P. falciparum gene encoding a kelch protein on chromosome 13 (k13) are associated with artemisinin resistance and have arisen spread in the Great Mekong subregion, including the China-Myanmar border. Multiple copies of the plasmepsin II/III (pm2/3) genes, located on chromosome 14, have been shown to be associated with PPQ resistance. METHODS: The therapeutic efficacy of DHA-PPQ for the treatment of uncomplicated P. falciparum was evaluated along the China-Myanmar border from 2010 to 2014. The dry blood spots samples collected in the efficacy study prior DHA-PPQ treatment and from the local hospital by passive detection were used to amplify k13 and pm2. Polymorphisms within k13 were genotyped by capillary sequencing and pm2 copy number was quantified by relative-quantitative real-time polymerase chain reaction. Treatment outcome was evaluated with the World Health Organization protocol. A linear regression model was used to estimate the association between the day 3 positive rate and k13 mutation and the relationship of the pm2 copy number variants and k13 mutations. RESULTS: DHA-PPQ was effective for uncomplicated P. falciparum infection in Yunnan Province with cure rates > 95%. Twelve non synonymous mutations in the k13 domain were observed among the 268 samples with the prevalence of 44.0% and the predominant mutation was F446I with a prevalence of 32.8%. Only one sample was observed with multi-copies of pm2, including parasites with and without k13 mutations. The therapeutic efficacy of DHA-PPQ was > 95% along the China-Myanmar border, consistent with the lack of amplification of pm2. CONCLUSION: DHA-PPQ for uncomplicated P. falciparum infection still showed efficacy in an area with artemisinin-resistant malaria along the China-Myanmar border. There was no evidence to show PPQ resistance by clinical study and molecular markers survey. Continued monitoring of the parasite population using molecular markers will be important to track emergence and spread of resistance in this region.

Monitoring and evaluation of intervals from onset of fever to diagnosis before "1-3-7" approach in malaria elimination: a retrospective study in Shanxi Province, China from 2013 to 2018.

BACKGROUND: China's 1-3-7 approach was extensively implemented to monitor the timeframe of case reporting, case investigation and foci response in the malaria elimination. However, activities before diagnosis and reporting (before '1') would counteract the efficiency of 1-3-7 approach but few data have evaluated this issue. This study aims to evaluate the timelines between onset of fever and diagnosis at healthcare facilities in Shanxi Province. METHODS: Routine data were extracted from IDIRMS and NMISM database from 2013 to 2018. Time intervals between onset of fever and healthcare-seeking and between healthcare-seeking and diagnosis were calculated. Each of the documented malaria cases was geo-coded and paired to the county-level layers of polygon. RESULTS: A total of 90 cases were reported in 2013-2018 in Shanxi Province, and 73% of cases reported at provincial health facilities. All malaria cases were imported from Africa (90%) and Southeast Asia (10%) especially around the Chinese Spring Festival (n = 46, 51%). The median days between fever and healthcare-seeking and between healthcare-seeking and diagnosis of malaria were 3 and 2, respectively. CONCLUSIONS: The current "1-3-7" approach is well executed in Shanxi Province, but delays intervals observed in case finding before 1-3-7 approach occurred in all levels of facilities in Shanxi Province, which imply that more efforts are highlighted for timely case finding. Health education should be provided for improving awareness of healthcare-seeking, and various technical training aiming at the physicians should be carried out to improve diagnosis of malaria.

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.

Malaria in China, 2011-2015: an observational study.

OBJECTIVE: To ascertain the trends and burden of malaria in China and the costs of interventions for 2011-2015. METHODS: We analysed the spatiotemporal and demographic features of locally transmitted and imported malaria cases using disaggregated surveillance data on malaria from 2011 to 2015, covering the range of dominant malaria vectors in China. The total and mean costs for malaria elimination were calculated by funding sources, interventions and population at risk. FINDINGS: A total of 17 745 malaria cases, including 123 deaths (0.7%), were reported in mainland China, with 15 840 (89%) being imported cases, mainly from Africa and south-east Asia. Almost all counties of China (2855/2858) had achieved their elimination goals by 2015, and locally transmitted cases dropped from 1469 cases in 2011 to 43 cases in 2015, mainly occurring in the regions bordering Myanmar where Anopheles minimus and An. dirus are the dominant vector species. A total of United States dollars (US$) 134.6 million was spent in efforts to eliminate malaria during 2011-2015, with US$ 57.2 million (43%) from the Global Fund to Fight AIDS, Tuberculosis and Malaria and US$ 77.3 million (57%) from the Chinese central government. The mean annual investment (US$ 27 million) per person at risk (574 million) was US$ 0.05 (standard deviation: 0.03). CONCLUSION: The locally transmitted malaria burden in China has decreased. The key challenge is to address the remaining local transmission, as well as to reduce imported cases from Africa and south-east Asia. Continued efforts and appropriate levels of investment are needed in the 2016-2020 period to achieve elimination.

Receptivity to malaria in the China-Myanmar border in Yingjiang County, Yunnan Province, China.

BACKGROUND: The re-establishment of malaria has become an important public health issue in and out of China, and receptivity to this disease is key to its re-emergence. Yingjiang is one of the few counties with locally acquired malaria cases in the China-Myanmar border in China. This study aimed to understand receptivity to malaria in Yingjiang County, China, from June to October 2016. METHODS: Light-traps were employed to capture the mosquitoes in 17 villages in eight towns which were categorized into four elevation levels: level 1, 0-599 m; level 2, 600-1199 m; level 3, 1200-1799 m; and level 4, > 1800 m. Species richness, diversity, dominance and evenness were used to picture the community structure. Similarity in species composition was compared between different elevation levels. Data of seasonal abundance of mosquitoes, human biting rate, density of light-trap-captured adult mosquitoes and larvae, parous rate, and height distribution (density) of Anopheles minimus and Anopheles sinensis were collected in two towns (Na Bang and Ping Yuan) each month from June to October, 2016. RESULTS: Over the study period, 10,053 Anopheles mosquitoes were collected from the eight towns, and 15 Anopheles species were identified, the most-common of which were An. sinensis (75.4%), Anopheles kunmingensis (15.6%), and An. minimus (3.5%). Anopheles minimus was the major malaria vector in low-elevation areas (< 600 m, i.e., Na Bang town), and An. sinensis in medium-elevation areas (600-1200 m, i.e., Ping Yuan town). In Na Bang, the peak human-biting rate of An. minimus at the inner and outer sites of the village occurred in June and August 2016, with 5/bait/night and 15/bait/night, respectively. In Ping Yuan, the peak human-biting rate of An. sinensis was in August, with 9/bait/night at the inner site and 21/bait/night at the outer site. The two towns exhibited seasonal abundance with high density of the two adult vectors: The peak density of An. minimus was in June and that of An. sinensis was in August. Meanwhile, the peak larval density of An. minimus was in July, but that of An. sinensis decreased during the investigation season; the slightly acidic water suited the growth of these vectors. The parous rates of An. sinensis and An. minimus were 90.46 and 93.33%, respectively. CONCLUSIONS: The Anopheles community was spread across different elevation levels. Its structure was complex and stable during the entire epidemic season in low-elevation areas at the border. The high human-biting rates, adult and larval densities, and parous rates of the two Anopheles vectors reveal an exceedingly high receptivity to malaria in the China-Myanmar border in Yingjiang County.

[Malaria Situation in the People's Republic of China in 2015].

The 2015 malaria epidemiological data reported through the annual malaria statistics reporting system were collected and analyzed. Totally 3 288 malaria cases were reported in 664 counties of 31 Provinces/Municipalities/Autonomous Regions （P/M/A） in 2015, which increased by 6.8% in comparison to that of 2014 （3 078 cases）, and the incidence in 2015 was 0.024 0/10 000. The cases were reported primarily from Provinces of Yunnan （18.4%, 606/3 288）, Jiangsu （12.3%, 405/3 288）, Sichuan （8.8%, 290/3 288）, Guangxi （7.2%, 236/3 288） and Shandong（6.4%, 212/3 288）. Of all the cases, 40（1.2%, 40/3 288） were indigenous cases, mainly distributed in the border area of Yunnan （six counties）, Tibet （one county）, Liaoning （one county） and Hainan （one county）. There was one case of whom the source of infection was unknown. The locally-infected falciparum malaria was only found in Cangyuan County of Yunnan（1 case）. The prevalence of indigenous malaria in Motuo County of the Tibet Autonomous Region was over 1/10 000. Meanwhile, there were 3 248（98.8%, 3 248/3 288） abroad-imported cases which widely distributed in the 31 P/M/As. In addition, 3 265（99.3%, 3 265/3 288） of the reported cases were confirmed in reference laboratories, comprising 878 cases of Plasmodium vivax（26.9%, 878/3 265） 1 992 cases of P. falciparum（61.0%, 1 992/3 265）, 76 cases of P. malariae（2.3%, 76/3 265）, 272 cases of P. ovale（8.3%, 272/3 265） and 47 cases of mixed infection（1.4%, 47/3 265）. Furthermore, 163 cases（5.0%, 163/3 288） with severe clinical symptoms were reported in 14 P/M/As, with 20 deaths（0.6%, 20/3 288） in 10 P/M/As. Totally 3 116 malaria cases were reported through the China Information System for Disease Control and Prevention, including 39 indigenous cases. These data reflect achievements in malaria elimination, despite that challenges remain in boarder areas of Yunnan Province and in Motuo County of the Tibet Autonomous Region. Efforts are still needed in risk assesment for malaria re-transmission.

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.

[Malaria Situation in the People' s Republic of China in 2014].

The 2014 malaria epidemiological data reported through the annual malaria statistics reporting system were collected and analyzed. A total of 3 078 malaria cases were reported in 680 counties of 30 Provinces/ Municipalities/Autonomous Regions (P/M/A)(except Inner Mongolia) in 2014, decreased by 25.4% compared with the 4 128 cases in 2013. The incidence rate was 0.022 6/10 000. More cases distributed in Yunnan (17.3%, 533/3 078), Jiangsu (11.5%, 355/3 078), Sichuan (8.6%, 266/3 078), Henan (7.0%, 216/3 078) and Zhejiang (7.0%, 215/3 078) Provinces. Of all the cases, 56 (1.8%) were indigenous cases, mainly from the border area of Yunnan (comprising 9 counties) and the Tibet Autonomous Region (one county). Locally-infected falciparum malaria was only found in Yingjiang County (4 cases) and Cangyuan County (2 cases) of Yunnan. Indigenous malaria prevalence was of over 1/10 000 in Motuo County and Yingjiang County. There were 3 021 abroad-imported cases of malaria (98.1% ), which widely distributed in the 30 P/M/As. In addition, one case of quartan malaria with long latency was reported' in Guangdong Province. Of all the reported cases, 3 057 (99.3%) were further confirmed by plasmodium species, comprising 846 cases of vivax malaria (27.7%), 1 882 cases of falciparum malaria (61.6%), 3 cases of quartan malaria (1.7%), 231 cases of ovale malaria (7.6%), 44 cases of mixed infections, and one case of P. knowlesi malaria. Furthermore, 170 cases (5.5%) with severe conditions were reported in 16 P/M/As, and 25 deaths were reported in 15 P/M/As. In summary, remarkable achievements have been made in eliminating malaria in China, despite increases in imported cases. The border areas of Yunnan and Motuo County of Tibet Autonomous Region remain the key regions for malaria elimination. Efforts are needed to reinforce the management of imported cases and the treatment of complicated malaria.

[Opportunities, Challenges and Strategies for Malaria Elimination in the Tibet Autonomous Region of China].

This review summarizes the endemic characteristics and influencing factors of malaria in the Tibet Autonomous Region of China, as well as the opportunities and challenges for malaria elimination in this region. Recommendations on strategies for malaria control are also made.

[Preliminary Evaluation of Potential Transmission Risk of Malaria after Earthquake in Cangyuan County, Yunnan Province].

OBJECTIVE: To evaluate the transmission risk and the prevalence potential of malaria in Cangyuan ounty after earthquake. METHODS: The malaria epidemiological data were collected through the web-based reporting system and the malaria statistics annual reporting system from 2005 to April 2015, and the epidemic factors of nalaria after earthquake in the recent three years in Cangyuan County of Yunnan Province were analyzed. RESULTS: according to the web-based reporting system, 799 malaria cases were reported in Cangyuan County from 2005 to April 2015, of which 652 w6re vivax malaria, 127 falciparum malaria, and 20 unclassified. The highest number of cases occurred in 2006 (n=326), and one indigenous falciparum malaria case was reported after earchquake. In iddition, the cases were mainly distributed in Mangka (n=320, 40.1%), Banlao (n=191, 23.9%), Banhong (n=98, 12.3%) and Mengdong (n=92, 11.5%). According to the annual reporting system, there were a total of 519 ndigenous cases (58.4%) and 370 imported cases (41.6%) from 2005 to April 2015. The proportion of indigenous ,ase was above 65% in each year except for 2006, when it was less than 15%. The risk indicator in western ownships of Canyuan County was higher, especially in Mangka and Mengjiao. CONCLUSIONS: There is a potential isk of malaria transmission in Cangyuan County of Yunnan province, due to the huge natural, social and biological ilterations after earthquake and the yet presence of malaria transmission vehicle.

[Screening Radius of Active Case Detection and the Malaria Parasite Rate of Carriers in China-Myanmar Border].

OBJECTIVE: To explore the effective screening radii of active case detection of the 1-3-7 surveillance and response strategy, and investigate the malaria parasite rate of carriers in China-Myanmar border. METHODS: Three villages with indigenous malaria cases in Yingjiang County of Yunan Province were selected as study sites. The persons lived around the indigenous cases (index case) within the radius of 100 m, 300 m, 500 m, and 1 km were screened by microscopy and nested PCR. Parasite rate of asymptomatic carriers at different radii were calculated. RESULTS: Among 278 blood samples, the parasite rate of asymptomatic carriers was 1.1% (3/278) and 2.2% (6/278) using microscopy and nested PCR, respectively. Based on the results of nested PCR, all the asymptomatic carriers could be detected within a 300 m radius around the index case, and with the highest proportion (66.7%) in the radius of 101-300 m. CONCLUSION: The asymptomatic carriers of malaria parasites in the China-Myanmar border area can be effectively detected within a 300 m screening radius of index case by using nested PCR.

Operational research on malaria control and elimination: a review of projects published between 2008 and 2013.

A literature review for operational research on malaria control and elimination was conducted using the term 'malaria' and the definition of operational research (OR). A total of 15 886 articles related to malaria were searched between January 2008 and June 2013. Of these, 582 (3.7%) met the definition of operational research. These OR projects had been carried out in 83 different countries. Most OR studies (77%) were implemented in Africa south of the Sahara. Only 5 (1%) of the OR studies were implemented in countries in the pre-elimination or elimination phase. The vast majority of OR projects (92%) were led by international or local research institutions, while projects led by National Malaria Control Programmes (NMCP) accounted for 7.8%. With regards to the topic under investigation, the largest percentage of papers was related to vector control (25%), followed by epidemiology/transmission (16.5%) and treatment (16.3%). Only 19 (3.8%) of the OR projects were related to malaria surveillance. Strengthening the capacity of NMCPs to conduct operational research and publish its findings, and improving linkages between NMCPs and research institutes may aid progress towards malaria elimination and eventual eradication world-wide.

[Methods of detecting asymptomatic plasmodium parasites carriers].

More attention has increasingly been given to asymptomatic carriers of plasmodium parasites as a source of infection in malaria elimination settings. However, asymptomatic infections can hardly be detected by microscopy and rapid diagnostic tests (RDTs) because of no symptoms and low parasitemia. This review summarizes the evolution of methods or tests which are currently used in the field.

[Risk assessment for malaria elimination in P. R. China].

OBJECTIVE: To identify the risk area in China during the malaria elimination process, and provide the evidence for promotion of the national malaria elimination programme and implementation of elimination strategy. METHODS: Data collection was conducted in 24 endemic provinces in 2010, including data of transmission capacity, potential risk of malaria transmission and the capacity of health professional team at county level. Quantitative assessment of the malaria transmission risk as well as the capacity of health facilities were conducted based on the calculation of malaria transmission risk index (MTI) and health facilities capacity index (CI). ArcGIS 10.0 was used to develop the risk map based on the outcome of quantitative assessment. RESULTS: The data of transmission capacity, potential risk of transmission and the capacity of health professional team were collected from 2147 counties in 24 provinces. Based on MTI and CI calculated for each county, statistic results showed that about 40% of the counties were under the average level of both MTI and CI. The relationship among potential risk of transmission, the capacity of health professional team and malaria incidence were analyzed in three dimensions, and four types were categorized among 2147 counties. Type I (super-high risk area) counties (20) distributed in Yunnan (9), Guangxi (5), Henan (1), Hunan (1), Hebei (1), Sichuan (1), Chongqing (1), and Tibet (1). 17 counties were classified into type II (high risk area) area, distributed in Yunnan (3), Guangxi (2), Guizhou (2), Shaanxi (2), Guangdong (1), Jiangxi (1), Hubei (1), Sichuan (1), Gansu (1), Hebei (1), Fujian (1) and Tibet (1). A total of 170 type III (moderate risk area) counties distributed in 19 provinces including Yunnan (15), Guizhou (14), Hebei (14), Sichuan (13), Shanxi (10), Guangxi (9), Hunan (9), Anhui (9), Jiangsu (9), Shaanxi (9), Shandong (9), Chongqing (8), Gansu (8), Jiangxi (7), Henan (7), Fujian (6), Guangdong (5), Hubei (5), and Zhejiang (4). 1940 type IV (low risk area) counties distributed in 24 provinces. CONCLUSION: The distribution of four types of risk area for malaria elimination is identified in China.

A potential threat to malaria elimination: extensive deltamethrin and DDT resistance to Anopheles sinensis from the malaria-endemic areas in China.

BACKGROUND: Insecticide resistance in malaria vectors is a growing concern in many countries and requires immediate attention because of the limited chemical arsenal available for vector control. There is lack of systematic and standard monitoring data of malaria vector resistance in the endemic areas, which is essential for the ambitious goal of malaria elimination programme of China. METHODS: In 2010, eight provinces from different malaria endemic region were selected for study areas. Bioassays were performed on F1 progeny of Anopheles sinensis reared from wild-caught females using the standard WHO susceptibility test with diagnostic concentrations of 0.25% deltamethrin and 4% DDT. RESULTS: For An. sinensis, the results indicated that exposure to 0.25% deltamethrin of F1 families with mortalities ranging from 5.96% to 64.54% and less than 80% mortality to DDT at the diagnostic concentration of 4% across the study areas. CONCLUSIONS: Anopheles sinensis was completely resistant to both deltamethrin and DDT, and resistance to pyrethroid has risen strikingly compared to that recorded during 1990s. The results highlight the importance of longitudinal insecticide resistance monitoring and the urgent need for a better understanding of the status of insecticide resistance in this region.

Students' awareness of malaria at the beginning of national malaria elimination programme in China.

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.

[Malaria situation in the People's Republic of China in 2012].

OBJECTIVE: To analyze malaria situation and epidemic characteristics in 2012 in China, and provide evidence and reference for National Malaria Elimination Programme (NMEP) performance. METHODS: The epidemiological data of malaria cases reported through the annual malaria statistics reporting system in 2012 were collected and analyzed using Microsoft Excel 2010 and ArcGIS 10.0. RESULTS: Totally 2,718 malaria cases were reported from 620 counties of 31 Provinces/Municipalities/Autonomous Regions (P/M/A) in 2012, representing 39.3% reduction compared with 4,479 cases in 2011, and the annual incidence was 0.020 2/10,000. The cases were mainly reported from provinces of Yunnan (31.4%, 853/2,718), Guangxi (8.1%, 220/2,718), Jiangsu (7.3%, 198/2,718), Hunan (5.8%, 158/2,718), and Sichuan (5.7%, 155/2,718). Among the 620 counties with reported cases, 8 counties including Motuo (8.1818/10,000) in Tibet, Ruili (8.248 9/10,000), Yingjiang (3.021 4/10,000), Longchuan (1.4778/10,000), Mangshi (1.4244/10,000), Tengchong (3.1601/10,000) and Cangyuan (1.340 0/10,000) in Yunnan, and Shanglin (2.355 1/10,000) in Guangxi had an incidence between 1/10,000 and 10/10,000, 96 counties had an incidence between 0.1/10,000 and 1/10,000, and that of the others was below 0.1/10,000. The laboratory confirmed cases took 95.6% (2.599/2,718) while the other 4.4% (119/2,718) were clinically diagnosed. In detail, 39.7% (1080/2,718) were P. vivax cases, 52.2% (1.419/2,718) were P. falciparum cases, 1.6%(44/2,718) were mixed infection of P. vivax and P. falciparum, and 2.1% (56/2,718) were P. ovale and P. malariae cases. However, the proportions of lab-confirmed cases in Xinjiang, Jilin, Heilongjiang, Tibet, Ningxia, Shanxi and Qinghai were below 75.0%. A total of 182 (6.7%, 182/2,718) indigenous cases were reported from 41 counties in 5 provinces including 20 counties of Yunnan, 15 counties of Anhui, 4 counties of Hubei, 1 county of Tibet and 1 county of Guangxi, consisting of 38 (20.9%, 38/182) clinically diagnosed cases (30 cases from Yunnan and 8 from Tibet), 133 (73.1%, 133/182) P. vivax cases (92 cases from Yunnan, 30 from Anhui, 9 from Hubei, 1 from Guangxi and 1 from Tibet), and 9 (4.9%, 9/182) P. falciparum cases as well as 2 (1.1%, 2/182) mixed infections from Yunnan. The incidence of indigenous cases between 1/10,000 and 10/10,000 was found only in Motuo County of Tibet, and that of the others was below 1/10,000. Out of the 2,718 malaria cases, a proportion of 91.0% (2,474/2,718) were reported as the abroad-imported cases who distributed in 29 provinces, and the remaining 2.3% (62/2,718) were domestically-mobile cases reported from 10 provinces. Totally 145 (5.3%, 145/2,718) severe cases were reported from 15 provinces and 15 (0.6%, 15/2,718) malaria deaths were from 11 provinces. CONCLUSION: Generally the indigenous malaria was reduced closer to the NMEP target, while malaria importation becomes an increasing challenge.

[Analysis report of the national technique competition for diagnosis of parasitic diseases in 2012: I. Capability analysis of Plasmodium detection].

OBJECTIVE: To analyze the result of the national technique competition for diagnosis of parasitic diseases in 2012, so as to understand the capability of detection on Plasmodium parasites among professionals from institutes for disease control and prevention at different levels. METHODS: Four professionals from institution were selected as contestants (age < or = 45 and at least two contestants from county-level institution). The content of the competition included making thick and thin blood slides of Plasmodium (3 slides in 30 min, 10 scores as full marks and 6 as passing score) and identification of species and number with microscopy (5 slides, 8 min per slide, 30 scores as full marks and 18 as passing score). All contestants were grouped by gender, age, professional title, level of institution, classification according to malaria endemicity, geographical location and economic development of the province. Their scores were statistically analyzed by SPSS 16.0 software. RESULTS: The average score of blood smear making test in 120 contestants from 30 provinces was 8.7, the highest was 10 and the lowest was 5.8, 118 (98.3%) contestants passed the test. The average score of blood smear reading was 16.0, the highest was 29 and the lowest was 0, 52 (43.3%) contestants passed the test. There were no significant differences for the scores among genders, ages (< or = 30, 31-40, > 40), professional titles (junior, intermediate and senior), institution levels (provincial, municipal or county level) (P > 0.05). However, there was a significant difference among provinces with different malaria endemicity, geographical location and development status (P < 0.05). For the blood slide-making and film-reading, scores of contestants from malaria endemic provinces including Class I (9.29 +/- 0.41, 18.17 +/- 6.42), Class II (8.92 +/- 0.79, 18.31 +/- 6.94) and Class III (8.61 +/- 0.89, 15.63 +/- 7.52) were higher than those from non-endemic provinces (7.95 +/- 1.00, 10.19 +/- 7.01) (P < 0.01). Scores of contestants from southern provinces (9.16 +/- 0.61, 18.82 +/- 6.78) were significantly higher than that from northern ones (8.30 +/- 0.99, 13.23 +/- 7.45) (P < 0.01). The film-reading scores were significantly higher in those from eastern provinces (18.20 +/- 6.88) than those from western (13.39 +/- 7.60) (P < 0.05), while no significant difference was found in blood slide-making (P > 0.05). CONCLUSION: The capability of malaria parasite detection is imbalanced.