Malaria control and prevention towards elimination: data from an eleven-year surveillance in Shandong Province, China

Abstract

BackgroundShandong Province experienced a declining malaria trend of local-acquired transmission, but the increasing imported malaria remains a challenge. Therefore, understanding the epidemiological characteristics of malaria and the control and elimination strategy and interventions is needed for better planning to achieve the overall elimination goal in Shandong Province.MethodsA retrospective study was conducted and all individual cases from a web-based reporting system were reviewed and analysed to explore malaria-endemic characteristics in Shandong from 2005 to 2015. Annual malaria incidence reported in 2005–2015 were geo-coded and matched to the county-level. Spatial cluster analysis was performed to evaluate any identified spatial disease clusters for statistical significance. The space–time cluster was detected with high rates through the retrospective space–time analysis scanning using the discrete Poisson model.ResultsThe overall malaria incidence decreased to a low level during 2005–2015. In total, 1564 confirmed malaria cases were reported, 27.1% of which (n = 424) were indigenous cases. Most of the indigenous case (n = 339, 80.0%) occurred from June to October. However, the number and scale of imported cases have been increased but no significant difference was observed during months. Shandong is endemic for both Plasmodium vivax (n = 730) and Plasmodium falciparum (n = 674). The disease is mainly distributed in Southern (n = 710) and Eastern region (n = 424) of Shandong, such as Jinning (n = 214 [13.7%]), Weihai (n = 151 [9.7%]), and Yantai (n = 107 [6.8%]). Furthermore, the spatial cluster analysis of malaria cases from 2005 to 2015 indicated that the diseased was not randomly distributed. For indigenous cases, a total of 15 and 2 high-risk counties were determined from 2005 to 2009 (control phase) and from 2010 to 2015 (elimination phase), respectively. For imported cases, a total of 26 and 29 high-risk counties were determined from 2005 to 2009 (control phase) and from 2010 to 2015 (elimination phase), respectively. The method of spatial scan statistics identified different 13 significant spatial clusters between 2005 and 2015. The space–time clustering analysis determined that the most likely cluster included 14 and 19 counties for indigenous and imported, respectively.ConclusionsIn order to cope with the requirements of malaria elimination phase, the surveillance system should be strengthened particularity on the frequent migration regions as well as the effective multisectoral cooperation and coordination mechanisms. Specific response packages should be tailored among different types of cities and capacity building should also be improved mainly focus on the emergence response and case management. Fund guarantees for scientific research should be maintained both during the elimination and post-elimination phase to consolidate the achievements of malaria elimination.

Malaria in China: a longitudinal population-based surveillance study

“…The proportion of malaria deaths attributed to P. falciparum was 87.7% and 6.8% by P. vivax. These results were consistent with other reports [19,[21][22][23].…”

Management of imported malaria cases and healthcare institutions in central China, 2012–2017: application of decision tree analysis

“…Poor performance in awareness, attitudes and practices of international labourers from rural areas, low capacity for malaria diagnosis in lower-level administrative healthcare institutions, and infrequency of malaria cases make these challenging characteristics of imported malaria in China [16,20,30]. A critical problem has been observed after a literature review of the challenge to tackle imported malaria in China [30,[34][35][36][37][38][39][40]. It is well known that China's strong healthcare system has wiped out a severe local malaria epidemic through mass intervention and specific strategies, which defines superiority in medical resources of China [41][42][43][44][45].…”

“…Within the system, high quality malaria medical resources could be used to cope with a small number of migrant febrile cases intensively so its effectiveness could be unparalleled. It is an active, rather than passive, imported malaria management system [40] in which each migrant febrile patient communicates closely with and is in the charge of a local healthcare institution. More importantly, there should be a consensus that all Chinese citizens should undertake due obligation to reduce the burden of malaria and spare no effort to help achieve the goal of malaria elimination together with the Chinese Government, particularly in the context of imported malaria.…”

Toward the Elimination of Malaria in China: A Retrospective Analysis of Malaria-Endemic Characteristics and Prevention Effects in Yantai, Shandong Province, 1951 to 2017

“…In this study, the data before 2004 were collected from annual paper-based surveillance data and compilation of information on the elimination of malaria (Wang et al 2010, Chen et al 2015. Since 2004, each case that has been obtained through the Infectious Diseases Information Reporting Management System (IDIRMS; http://chinacdc.cn) has been subjected to rigorous quality control reviews (Kong et al 2017, Feng et al 2018. Data parameters included morbidity rates, case types, diagnostic approaches, and prevention and treatment measures, as well as the age, sex, occupation, and recent travel history of the malaria patient.…”

“…Indigenous cases refer to malaria transmitted by mosquitoes in endemic areas of China (Chen et al 2015). Imported malaria cases must meet all of the following criteria: a diagnosis of malaria and a travel history during the malaria transmission season and symptom development within 1 month after returning to China during the local transmission season (Kong et al 2017).…”