Characteristics of Imported Malaria and Species of Plasmodium Involved in Shandong Province, China (2012-2014)

Abstract

Malaria remains a serious public health problem in Shandong Province, China; therefore, it is important to explore the characteristics of the current malaria prevalence situation in the province. In this study, data of malaria cases reported in Shandong during 2012-2014 were analyzed, and Plasmodium species were confirmed by smear microscopy and nested-PCR. A total of 374 malaria cases were reported, 80.8% of which were reported from 6 prefectures. Of all cases, P. falciparum was dominant (81.3%), followed by P. vivax (11.8%); P. ovale and P. malariae together accounted for 6.4% of cases. Notably, for the first time since 2012, no indigenous case had been reported in Shandong Province, a situation that continued through 2014. Total 95.2% of cases were imported from Africa. The ratio of male/female was 92.5:1, and 96.8% of cases occurred in people 20-54 years of age. Farmers or laborers represented 77.5% of cases. No significant trends of monthly pattern were found in the reported cases. All patients were in good condition after treatment, except for 3 who died. These results indicate that imported malaria has increased significantly since 2012 in Shandong Province, especially for P. falciparum, and there is an emergence of species diversity.

Surveillance of Antimalarial Resistance Pfcrt, Pfmdr1, and Pfkelch13 Polymorphisms in African Plasmodium falciparum imported to Shandong Province, China

“…Nevertheless, there was an increasing trend of the malaria cases presented in Shandong from 2012 to 2015 due to the proportion of imported malaria (100%, 586/586) and the majority of them were P . falciparum cases returning from African countries (79.9%, 468/586) 29 , 30 . Since 2009, DHA + PQ and AS + AQ have been applied to against uncomplicated P .…”

Molecular epidemiological surveillance of Africa and Asia imported malaria in Wuhan, Central China: comparison of diagnostic tools during 2011–2018

“…Once errors happened during this program, the false negative would probably present. For example, in a previous study, there were 10 malaria cases failed to be identified by molecular methods due to the problems in nucleic acid extraction until reasons were found out by repeated experiments [54]. Therefore, the combining use of the four methods is quite necessary and highly recommended.…”

“…Therefore, prevention and treatment against P. falciparum should be highly considered in Wuhan. By the year elapsed, the Plasmodium species leading to imported malaria were becoming diversity just as the situation in another region of China, Shandong province [54]. The increase of imported P. vivax and P. ovalis cases may cause the re-introduction of malaria in those regions without cases [57,58].…”

Malaria Elimination in the People’s Republic of China: Current Progress, Challenges, and Prospects

“…Surveillance is highly recommended as a key intervention in the post-malaria elimination stage. However, decisive and rapid response to imported malaria is vital to prevent re-introduction and sustain malaria elimination [11,27,29,[49][50][51][52][53]. A shift from community to hospitals at the county and higher level for primary diagnosis was also recorded [8,27], indicative of a more active role of the main city airports as ports of entry.…”