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Background This study reports the analytical sensitivity and specificity of a Loop-mediated isothermal amplification (LAMP) and compares its amplification performance with conventional PCR, nested PCR (nPCR) and real-time PCR (qPCR). All the assays demonstrated in this study were developed based on Serine-rich Entamoeba histolytica protein (SREHP) gene as study model. Results A set of SREHP gene specific LAMP primers were designed for the specific detection of Entamoeba histolytica. This set of primers recorded 100% specificity when it was evaluated against 3 medically important Entamoeba species and 75 other pathogenic microorganisms. These primers were later modified for conventional PCR, nPCR and qPCR applications. Besides, 3 different post-LAMP analyses including agarose gel electrophoresis, nucleic acid lateral flow immunoassay and calcein-manganese dye techniques were used to compare their limit of detection (LoD). One E. histolytica trophozoite was recorded as the LoD for all the 3 post-LAMP analysis methods when tested with E. histolytica DNA extracted from spiked stool samples. In contrast, none of the PCR method outperformed LAMP as both qPCR and nPCR recorded LoD of 100 trophozoites while the LoD of conventional PCR was 1000 trophozoites. Conclusions The analytical sensitivity comparison among the conventional PCR, nPCR, qPCR and LAMP reveals that the LAMP outperformed the others in terms of LoD and amplification time. Hence, LAMP is a relevant alternative DNA-based amplification platform for sensitive and specific detection of pathogens.

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Aims: Psittacine birds such as parrots, macaws, cockatoos, lovebirds and parakeets, are widely reared as household pets or at aviary due to their attractive features. However, the status of virus-causing diseases of psittacine species in Malaysia is fairly under-documented. Therefore, this study was aimed to detect the presence of three common avian viruses that infect psittacine birds, i.e. beak and feather disease virus (BFDV), avian polyomavirus and avian papillomavirus. Methodology and results: Faecal samples from twelve asymptomatic captive psittacine birds of different species were collected from an undisclosed animal garden in Serdang, Selangor, Malaysia. Briefly, the sample was homogenised and resuspended with SM buffer with the ratio 1:1 (weight of sample/g: volume of SM buffer/mL) before centrifugation at 1,000 × g for 20 min. The supernatant was collected and filtered before subjected to genomic DNA extraction using a commercialised kit. Polymerase chain reaction (PCR) technique was used to screen the V1, VP1 and L1 genes of beak and feather disease virus (BFDV), avian polyomavirus and avian papillomavirus, respectively. Findings revealed that the samples were negative for BFDV and avian polyomavirus. However, positive results of 1.5 kbp PCR amplicon were detected for avian papillomavirus in four out of the 12 samples (33.33%), which was from the white-crested cockatoo, African grey parrot, yellow-collared macaw and Senegal parrot. Sequence analysis of the L1 gene from the Senegal parrot Poicephalus senegalus revealed 93% identity to a reference Psittacus erithacus timneh avian papillomavirus. Conclusion, significance and impact of study: This study added to the limited prevalence data of three important avian viruses which infect captive psittacines in Seri Kembangan, Selangor, Malaysia. Avian papillomavirus, but not BFDV and avian polyomavirus, was detected in the collected captive psittacine birds. Therefore, a routine screening can be performed to monitor the health status of birds despite their asymptomatic manifestation, in order to prevent possible virus transmission.

Papillomaviruses (PVs), double-stranded circular DNA viruses, typically cause regressing papillomas (warts) on mucosal or keratinized epithelia of a wide spectrum of species. The viruses largely infect mammals, whereby PV infections in humans, bovines, and rabbits are extensively reported. However, studies on non-mammalian PVs, particularly avian ones, are relatively lacking and worthy of investigation. This study performed a meta-analysis post-systematic review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines to evaluate the occurrences of avian papillomaviruses (APVs) in bird species and effective materials used for virus detection. The electronic databases Science Direct, Medline via PubMed, and Google Scholar were used to search for the journal articles. Upon article eligibility check, the QUADAS-2 was employed to assess the data. Of 1139 records, 31 were eligible for full-text review, but only 9 were significant for the final review. The results showed that APVs are highly prevalent among the Fringillidae family, with a proportion of 81%, followed by Laridae (30%) and Anatidae (13%). The pooled prevalence of APV in tissue samples was 38%, while in swab samples was 13%. Only one study reported positive APV from fecal materials (0.4%); hence, the reliability comparison between these three samples was not performed. This study concluded that APVs are most prevalent in the Fringillidae bird family, while tissues are the most suitable biological samples for APV screening and should be considered as a single sample material. From epidemiology, knowledge of APV incidences and distribution may assist in controlling papillomatosis in bird species.