ABSTRACT
Objective To identify 10 imported cases of Plasmodium ovale wallikeri infection in Sichuan Province from January to April in 2018, and to analyze the P. ovale wallikeri infection status of 1 079 malaria cases reported in this area from 2013 to 2017. Methods The 10 cases collected in 2018 were examined by microscopy, RDT, nested PCR and sequencing. Meanwhile, the retrospective detections of P. ovale wallikeri of the 1 079 blood samples from past 5 years were conducted by nested PCR using wallikeri-specific primers. Results For the 10 cases, the microscopic examinations were all positive for P. ovale, of which 2 were mixed infection with P. falciparum, and the results of RDT were all positive for Plasmodium. Except for 2 cases of P. falciparum infection, the routine nested PCR showed negative results for rest of the samples. The nested PCR for the specific detection of P. ovale wallikeri showed the 10 cases were all positive, and the following sequencing confirmed that the 10 cases were all infected with P. ovale wallikeri. The retrospective tests discovered 2 cases both reported in 2017 and recorded as simple P. falciparum infection tuned out to be mixed infection with P. falciparum and P. ovale wallikeri. Conclusion This is the first time that imported P. ovale wallikeri infection is founded in Sichuan Province.
ABSTRACT
Objective To identify 10 imported cases of Plasmodium ovale wallikeri infection in Sichuan Province from January to April in 2018, and to analyze the P. ovale wallikeri infection status of 1 079 malaria cases reported in this area from 2013 to 2017. Methods The 10 cases collected in 2018 were examined by microscopy, RDT, nested PCR and sequencing. Meanwhile, the retrospective detections of P. ovale wallikeri of the 1 079 blood samples from past 5 years were conducted by nested PCR using wallikeri-specific primers. Results For the 10 cases, the microscopic examinations were all positive for P. ovale, of which 2 were mixed infection with P. falciparum, and the results of RDT were all positive for Plasmodium. Except for 2 cases of P. falciparum infection, the routine nested PCR showed negative results for rest of the samples. The nested PCR for the specific detection of P. ovale wallikeri showed the 10 cases were all positive, and the following sequencing confirmed that the 10 cases were all infected with P. ovale wallikeri. The retrospective tests discovered 2 cases both reported in 2017 and recorded as simple P. falciparum infection tuned out to be mixed infection with P. falciparum and P. ovale wallikeri. Conclusion This is the first time that imported P. ovale wallikeri infection is founded in Sichuan Province.
ABSTRACT
Objective To analyze the laboratory diagnosis results and epidemiological characteristics of imported malaria cases in Chongqing Municipality in 2015. Methods According to the Standard Operating Procedures of Malaria Diagnosis Ref-erence Laboratory Manual,all the blood samples collected from the imported malaria patients were detected by microscopy, RDT and nest PCR. Meanwhile,the epidemiological data of the malaria cases were collected from the Parasitic Diseases Informa-tion Management System and analyzed. Results Totally 31 cases of imported malaria were reported in Chonqing Municipality in 2015,among which,there were 2 vivax malaria cases(6.45%),23 falciparum malaria cases(74.19%),5 ovale malaria cas-es(16.13%),1 malariae malaria case(3.22%). For the 5 ovale cases,three of them were confirmed as Plasmodium ovale wal-likeri infection. Among all the cases,30 cases(96.77%)were from African countries,1(3.33%)was from Southeast Asia. Thir-ty patients were male,and 1 was female. All the patients were aged from 23-61 years. There was no obvious seasonality in the case distribution. Both the medians of duration from malaria attack to first visiting a doctor and from first visiting a doctor to diag-nosis were 2 days. The medical care units that the patients first visited were mainly county-level units,while those that made the diagnosis were mainly provincial level institutes. Conclusions All the malaria cases in Chongqing in 2015 are imported,no lo-cal cases have been found,which suggests that this municipality still maintain the malaria elimination state. However,the moni-toring and management of imported malaria cases as well as the training on malaria control for related medical staff still need to be strengthened.
ABSTRACT
In contrast to the gradual reduction in the number of locally transmitted malaria cases in China, the number of imported malaria cases has been increasing since 2008. Here, we report a case of a 39-year-old Chinese man who acquired Plasmodium ovale wallikeri infection while staying in Ghana, West Africa for 6 months in 2012. Microscopic examinations of Giemsa-stained thin and thick blood smears indicated Plasmodium vivax infection. However, the results of rapid diagnostic tests, which were conducted 3 times, were not in agreement with P. vivax. To further check the diagnosis, standard PCR analysis of the small-subunit rRNA gene was conducted, based on which a phylogeny tree was constructed. The results of gene sequencing indicated that this malaria is a variant of P. ovale (P. ovale wallikeri). The infection in this patient was not a new infection, but a relapse of the infection from the one that he had contracted in West Africa.