UNAIR NEWS – Rabies is a zoonotic disease (transmitted from animal to human) that has not been able to be overcome until now. It is presumably because the rabies vaccine seed that has been used so far is not compatible with the circulation of the rabies virus in Indonesia. This condition prevents the neutralizing antibodies of the virus to be formed perfectly. Various molecular studies of the rabies virus (RABV) in Indonesia apparently have not been able to provide clear information about the molecular characteristics of the previous RABV isolates in Indonesia.
Dr. Jola Rahmahani M. Kes, drh., a lecturer of Faculty of Veterinary Medicine, Universitas Airlangga conducted a study to determine the characteristics of RABV circulation in order to determine the right method to control the spread of RABV in Indonesia.
Jolam explained, samples used are in form of brains from dogs infected with rabies virus from Sumatra (Veterinary Research and Investigation Center Region II Bukittinggi-Sumatra), Kalimantan (Veterinary Research and Investigation Center Regional V Banjarbaru-Kalimantan), Sulawesi (Maros-Sulawesi Veterinary Center), and Bali (Denpasar Veterinary Center).
“A total of 12 samples were isolated from the four islands. Each sample is made a suspension with a concentration of 10 percent,” she said.
She then conducted a homology and phylogenetic analysis by comparing samples with rabies viruses in other Asian countries such as Indonesia, China, Thailand, India, Korea and the vaccine seed virus (Pasteur). Analysis of the sample is done to determine the possibility of mutation.
Molecular detection results showed that all samples isolated were rabies virus. The results of homology analysis between samples and the rabies virus in Indonesia are 98-99%. It shows that the virus isolated did not experience much change compared to the rabies virus that had been previously isolated.
“The homology score between the sample and the rabies virus from China is 92-93 percent. Phylogenetic analysis showed that the rabies virus isolated in Indonesia with the rabies virus isolated in China share the same ancestor, “Jola explained.
It caused homology scores between rabies virus isolates in Indonesia and rabies virus in China to be high. Meanwhile the homology score between the Indonesian rabies virus isolate and the Pasteur virus is quite low because it does not share the same ancestor.
“The difference in homology scores is thought to be due to rapid mutation and lack of proofreading in RNA virus replication,” she added
From this research, Jola concluded that one of the methods that could be done to prevent the spread of rabies was the use of local isolates as vaccine seeds. Because the antibodies produced by local isolates are able to neutralize the infection of the rabies virus more optimally. (*)
Author: Zanna Afia Deswari
Editor: Nuri Hermawan
Rahmahani, Jola et al. 2019. Antigenic site of nucleoprotein gene from Indonesian rabies virus isolates. Veterinary World. Vol 12(5): p. 724–728
Details of this research available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6584851/