Study on the polymorphism in circumsporozoite protein of Plasmodium vivax before the completion on elimination program of malaria, in Hainan province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the polymorphism in circumsporozoite protein of Plasmodium vivax before malaria was eliminated in Hainan island.</p><p><b>METHODS</b>PCR amplification, sequencing, and alignment methodologies were conducted and phylogenetic tree constructed.</p><p><b>RESULTS</b>From all the cases, 19 of them belonged to two types, with 18 as VK210 type and 1 as VK247 type. VK210 type could be divided into seven kinds of subtypes but VK247 had only one type. Ratio of tropical strain with temperate stain in VK210 type was explored between the two stages:control or elimination. Phylogenetic tree was constructed by amino acid sequencing which clearly manifested that VK210 type and VK247 type belonged to different clusters.</p><p><b>CONCLUSION</b>Compared the proportion of two types in the control stage, there was no significant difference seen in the stage of elimination.</p>

A Case of Plasmodium ovale wallikeri Infection in a Chinese Worker Returning from West Africa

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.

Epidemic status of Angiostrongylus cantonensis in Hainan island, China

OBJECTIVE@#To understand the current epidemiological status of Angiostrongylus cantonensis in Hainan island and provide the scientific evidences for prevention and control of the disease.@*METHODS@#The investigation on nature infection condition of intermediate hosts and final hosts of Angiostrongylus cantonensis were carried out in five counties, Hainan Province, and enzyme linked immunosorbent assay (ELISA) was employed to detect antibodies of Angiostrongylus cantonensis in human hosts.@*RESULTS@#A total of 1612 molluscs were examined, 21.3% of which harbored L3 of Angiostrongylus cantonensis. Among them, the infection rates of Pomacea canaliculata, Achatina fulica, Cepaea and Phlegm bilineatus were 12.36%(64/518), 22.66%(121/534), 20.93%(9/43), and 28.24%(146/517), respectively. Of the 118 rats trapped, 13 Rattus norvegicus were found to be infected with Angiostrongylus cantonensis. A total of 459 serum samples were collected and tested. 92 serum samples were Angiostrongylus cantonensis antibody-positive.@*CONCLUSIONS@#The survey revealed a wide distribution of Angiostrongylus cantonensis in Hainan island. Pomacea canaliculata and Achatina fulica are main intermediate hosts of Angiostrongylus cantonensis. Rattus novegicus is a nature definitive host, indicating that a considerable number of people are at risk of angiostrongyliasis. Health education, rigorous food inspection and surveillance are all needed to prevent angiostrongyliasis outbreaks in future.

Gene Typing of Merozoite Surface Protein 1 of Plasmodium falciparum isolates from Hainan Province * / 中国寄生虫学与寄生虫病杂志

Objective To identify the genotype of merozoite surface protein 1 (MSP1) of Plasmodium falciparum isolates from Hainan Province. Methods Nested PCR was applied to amplify the MSP1 of Blocks 2 and 3 Plasmodium falciparum isolates from Hainan Province. Two allelic family representitive gene fragments were sequenced.Results From 36 out of 39 blood samples from Plasmodium falciparum patients, 44 gene fragments of blocks 2 and 3 of the MSP1 were amplified, of which the MAD20 type allele was dominant(75%). followed by K1 type allele. No RO33 type allele was found. The mixed infection rate of the two different allelic type was 19 4%. Sequence analysis showed that the sequences of MAD20 and K1 type isolates from Hainan Province were highly homologous to that of the MAD20 and K1 allelic prototypes.Conclusion Two principal allelic types of MSP1 gene, MAD20 and K1 type, exist in malaria endemic areas in Hainan Province, the MAD20 type being the dominant.