evaluation-universal-nested-reverse-transcription-polymerase-chain

Evaluation of a Universal Nested Reverse Transcription Polymerase Chain Reaction for the Detection of Lyssaviruses

To detect rabies virus and other member species of the genus Lyssavirus within the family Rhabdoviridae, the pan-lyssavirus nested reverse transcription ...

Academy of Military Medical Sciences

Dogs play an important role in rabies transmission throughout the world. In addition to the severe human rabies situation in China, spillover of rabies virus from dogs in recent years has caused rabies outbreaks in sheep, cattle and pigs, showing that there is an increasing threat to other domestic animals. Two livestock rabies outbreaks were caused by dogs in Shanxi province, China from April to October in 2015, resulting in the deaths of 60 sheep, 10 cattle and one donkey. Brain samples from one infected bovine and the donkey were determined to be rabies virus (RABV) positive by fluorescent antibody test (FAT) and reverse transcription polymerase chain reaction (RT-PCR). The complete RABV N genes of the two field strains, together with those of two previously confirmed Shanxi dog strains, were amplified, sequenced and compared phylogenetically with published sequences of the N gene of RABV strains from Shanxi and surrounding provinces. All of the strains from Shanxi province grouped closely, sharing 99.6 %-100 % sequence identity, indicating the wide distribution and transmission of dog-mediated rabies in these areas. This is the first description of donkey rabies symptoms with phylogenetic analysis of RABVs in Shanxi province and surrounding regions. The result emphasizes the need for mandatory dog rabies vaccination and improved public education to eradicate dog rabies transmission. 

Livestock rabies outbreaks in Shanxi province, China.

Rabies is a major public health problem in developing countries in Asia and Africa. Although a number of laboratory diagnoses can be used for rabies control, the WHO and OIE recommended gold standard for rabies diagnosis is the direct fluorescent antibody test (FAT). However, FAT is not widely used in developing countries because of deficient financial sources to procure fluorescent microscope. Recently the direct rapid immunohistochemical test (dRIT) has been developed and has a worldwide promising application, particularly in developing countries, since its result can be read by inexpensive light microscopy, in addition to be consistent with that of FAT. However, no commercial conjugated antibody is available to meet the laboratory demand. We describe here the production of a monoclonal antibody (MAb) against rabies virus (RABV) N protein and its use as a biotinylated conjugate in a dRIT. Tested against a batch of 107 brain specimens representing a wide phylogenetic diversity of RABV collected from different animal species with multiple geographical origins in China, results showed that the dRIT had 100% specificity (95% CI 0.93-1.00) and 96.49% sensitivity (95% CI 0.88-1.00) as compared with the gold standard FAT. It therefore provides a simple, economical alternative to FAT, particularly for use in rabies diagnosis in developing countries.

Evaluation of monoclonal antibody-based direct, rapid immunohistochemical test for rabies diagnosis.

The compound 1,2,3,4,6-penta--galloyl-&beta;-d-glucose (PGG), a gallotannin present in various plants such as  Mill and , has a broad spectrum of antiviral effects. The present study investigated its potency against infection of mice with rabies virus (RABV). Results demonstrated that PGG strongly inhibited virus titers (50-fold), viral mRNA expression (up to 90%), and protein synthesis in vitro. Importantly, we found that PGG not only suppressed viral adsorption and entry, but also directly inactivated RABV through suppression of autophagy by mediating activation of the mTOR-dependent autophagy signaling pathway. In vivo, PGG (10 mg/kg) alleviated the clinical symptoms and reduced the mortality of infected mice by 27.3%. Collectively, our results indicate that PGG has potent anti-RABV effect, and merits further investigation as an anti-RABV drug.

Zhongzhong Tu

Key Laboratory of Jilin Province for Zoonosis Prevention and Control,
Institute of Military Veterinary Medicine,
Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary Medicine

Academy of Military Medical Sciences

Evaluation of a Universal Nested Reverse Transcription Polymerase Chain Reaction for the Detection of Lyssaviruses