| Babesiosis, caused by infection with intraerythrocytic parasites of the genus Babesia,is an emerging zoonosis in human, which can be transmitted by tick, but also are transmissible via blood transfusion. Globally, babesiosis, reported that the number of cases at home and abroad in recent years is on the rise, is an emerging infectious diseases. Only a few have been documented to infect humans, including Babesia microti, Babesia duncani, Babesia divergens, Babesia gibsoni and Babesia bovis. The clinical manifestations including headaches, fever, chills, nausea, vomiting, myalgia, altered mental status, disseminated intravascular coagulation, anaemia with hypotension, respiratory distress, hepatomegaly and renal insufficiency, or death. In immunosuppressed and immunodeficient individuals, such as very young children, the aged and frail, malignant tumor, blood transfusion recipients, Babesia infection can cause them to servious illness or death. And conventional antibiotics and parasitic resistance drugs cannot effectively kill this parasite. In order to reduce the risk of transmitted babesiosis, we should strengthen the epidemiological investigation. Therefore, rapid, sensitive, specific diagnosis methods for suspected patients clinically are essential.Due to the reasons of easy and simple operation, microscopic examination of blood smears is now the maindetection method. Immunological methods for detecting Babesia parasites have the disadvantage of relying on the presence of specific antibodies against those parasites, which may take days or weeks to develop in an infected animal or they are present for months after the infection has disappeared, making their usefulness very limited in acute disease cases, vaccinated animals or cleared hosts. Molecular methods aimed to detect nucleic acids have been proved to be useful when immunological methods do not work. Detecting nucleic acids is an indirect way of detecting the parasite so they are still considered indirect methods. However, the sensitivity and specificity of these methods are very high and over the past years many different approaches have been developed to detect Babesia species in their hosts and their vectors.Recently, LAMP has been developed successfully for diagnosis of a variety of pathogens infection.A loop-mediated isothermal amplification (LAMP) platform that targets specific sequences of the 18S rRNA genes of B. microti was developed. Specificity testing revealed that there was no cross-reaction with the other tick-borne parasites B. duncani, B. divergens, B. gibsoni, B. bovis and human blood parasitic protozoa P. falciparum, A. griffini. The sensitivity of the LAMP method was 300/ul gene copies. A loop-mediated isothermal amplification (LAMP) platform that targets specific sequences of the 18S rRNA genes of B. microti, B. duncani, B. divergens, B. gibsoni and B. bovis was developed. Specificity testing revealed that there was no cross-reaction with the other human blood parasitic protozoa P. falciparum, A. griffini. The sensitivity of the LAMP method was 20/ul gene copies. Moreover, its rapidity, sensitivity and ease of use suggest that LAMP assay may have potential application prospect for the easy diagnosis of human babesiosis.Blood parasitic protozoan is a threat to human health. Among them, malaria, and human babesiosis all are endemic in our country in different degrees. Plasmodium spp. are the most important blood protozoa, while some monkey malaria parasite infecting human have been founding recent years.P.knowlesi is considered to be the fifth malaria in human. P. cynomolgi in Southeast Asia, P. brasilianum, P. simium in South America can also been transmitted by anopheles mosquitoes and then infectious to humans. Babesiosis, a world emerging infectious zoonosis disesase is on the rise at home and abroad in recent years. And a report show that Babesia microti was identified in a rhesus monkey (Macaca mulatto) imported from China, Guangxi. Guangxi Zhuang Autonomous Region is situated in China’s southern area, where belong to subtropical area and haveing a humid climate. Guangxi has a plenty of animal diversity, most of them may serve as the intermedia hosts or reservoir hosts of parasite.To investigate the infection situation of blood parasitic protozoa in farmed Macaca fascicularis in an animal breeding ground in Nanning, Guangxi Zhuang Autonomous Region, so as to provide the evidence for the prevention and control of human blood parasitic protozoa. A total of 993 blood samples from farmed M. fascicμlaris were collected and stored on FTA cards. Among them,550 thin blood smears were made. Each 10 samples were mixed in groups, and then the Babesia spp. and Plasmodium spp. in the blood of M. fascicμlaris were detected by Nest-PCR and PCR, respectively. The positive groups were tested individually. The thin blood smears stained with Giemsa were examined microscopically when PCR reported the samples were positive. When detected by Nest-PCR, the positive rate of Babesia. microti was 6.95%(69/993); only 1 positive sample with Plasmodium inui was detected by PCR. Among the 22 positive thin blood smears detected by PCR,16 were determined with B. microti by microscopic examinations, on which the ring forms could be observed in the erythrocytes, but no hemozoin. The positive rate of B. microti in M. fascicμlaris in Guangxi Zhuang Autonomous Region is high, and the animal may play a role as a reservoir host in the transmission of B. microti. In the screening of B. microti with low infection density, Nest-PCR coordination with hybrid sample method, is an economic and effective means of epidemiological investigation. |
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