Serological investigation of vector-borne disease in dogs from rural areas of China

Objective:To evaluate the Anaplasma phagocytophilum(A.phagocytophilum),Ehrlichia canis(E.canis,Dirofilaria immitis(D.immitis)(canine heartworm),Borrelia burgdorferi(B.burgdorferi)infections in countryside dogs from Yunnan,Hainan and Anhui provinces.Methods:Serum samples were collected from 26 dogs in Yunnan.Hainan and Anhui provinces.The samples were tested using a commercial ELISA rapid diagnostic assay kit(SNAP^(?)4Dx^(?);IDEXX Laboratories,Inc.U.S.A.).Meaiiwliile,indirect immunofluorescence assay(IFA)recommended by WHO was conducted to delect IgG to A.phagocytophilum.Two methods were analyzed and compared.Results:The number of serologically positive dogs for IgG to A.phagocytophilum was only 2which was from Hainan province and none of the 26 dogs responded positive for E.canu.D.immitis(canine heartworm,and B.burgdorferi by ELISA rapid diagnostic method.The number of serologically positive dogs for IgG to A.phagocytophilum was 13(50%)by IFA method.Data of the two methods were analyzed by statistical software and the difference was statistically significant(P=0.002).Conclusions:It can be concluded that IFA method was more sensitive than ELISA rapid diagnostic method.However,we need conduct further and intensive epidemiology survey on tick-born diseases pathogens including.4.phagocytophilum,E.canis,D.immitis(canine heartworm),and B.burgdorferi which have public health significance.

High resolution melting real-time PCR detect and identify filarial parasites in domestic cats

Objective: To detect and identify filarial parasites in dried blood spots(DBS) collected from domestic cats using high resolution melting real-time PCR(HRM RT-PCR). Methods: A total of 208 DBS were collected from domestic cats in a brugian filariasis endemic areas in Surat Thani Province, southern Thailand. Microfilariae were found in 9 blood slides using Giemsa-stained thick blood film. The extracted DNA from blood spot volumes of 10 and 20 μL DBS with positive filarial parasites in cats were performed using HRM RT-PCR method. The primers were designed based on the partial mitochondrial 12S rRNA gene for identifying Brugia malayi, Brugia pahangi, Dirofilaria immitis. All purified samples were then detected. Results: Using different volumes of 10 μL and 20 μL DBS could easily distinguish filarial parasites and showed similar results. PCR amplicons of Brugia malayi, Brugia pahangi and Dirofilaria immitis were determined at melting peak(temperature) of 75.70℃, 77.46 ℃, and 73.56 ℃, respectively. All 9 positive DBS samples showed positive Brugia pahangi and similar nucleotide sequences. Conclusions: This HRM RT-PCR method is able to diagnose, identify and discriminate filarial parasites collected from DBS, which is simple and inexpensive compared with other probe-based genotyping methods. Furthermore, this method is useful to survey, prevent and control filariasis.

Prevalence of Canine Heartworm Disease in Stray Dogs of Grenada, West Indies

Dirofilariasis (heartworm disease) has been reported in Grenadian dogs. The aim of this cross-sectional study was to determine the prevalence of Dirofilaria immitis in stray dogs (n = 523) from the six Parishes of Grenada. Necropsy records were reviewed;information on the distribution and lesions of Dirofilaria immitis was recorded. A total of 144 from 523 dogs (27.5%;95% CI: 23.9% to 31.5%) were positive for Dirofilaria immitis on necropsy. This study shows that heartworm disease is prevalent in stray dogs in all the Parishes of mainland Grenada. This is a progressive, life-threatening disease and thus, there is a need to screen and prevent it within the stray dog population of Grenada.