UNAIR NEWS – Rabies or also known as mad dog disease is a viral infection of the brain and nerve system. Rabies is an acute infectious disease caused by a virus called Rhadovirus. Rabies is zoonotic (transmitted from animals to humans) and is classified as very dangerous because it has great potential to cause death. Rabies transmission occurs due to virus particles in the saliva of infected animals that enter the human body or other animals through a bite.
Generally, the rabies virus is found in wild animals. Some wild animals that spread the virus are skunks, raccoons, bats and foxes. However, in some countries, there are still many pets that carry the virus, including cats and dogs.
On March 2019, the Ministry of Health recorded reports from 22 provinces of 6,760 cases of bites carrying rabies. Of the 22 regions, Bali reported the highest incidence, 2,549 cases. After that West Nusa Tenggara (NTB) 920 cases, South Sulawesi 570 cases, North Sulawesi 469 cases, North Sumatra 425 cases, West Sumatra 348 cases, and West Kalimantan 341 cases.
The Government through the Ministry of Health and the Ministry of Agriculture continues to make efforts to prevent and control the spread of rabies. Some of these steps include providing socialization and education to the public about the dangers of disease, making government regulations, making flow charts regarding actions to be taken in handling the bite of Rabies Carrier Animals (GHPR), and mass vaccination (Data and Information Center of the Indonesian Ministry of Health, 2014).
However, these efforts have not been effective enough to solve the rabies problem in Indonesia. It has been proven since the discovery of rabies cases in NTB in early 2019. The incident caused an increase in the number of provinces affected by rabies from 24 regions to 25 regions (Kompasiana, 2019).
Lecturer in Faculty of Veterinary Medicine, Dr. Jola Rahmahani, M. Kes., Drh. mentioned that one of the things that were suspected to be the cause of this disease was that the vaccine seed used for mass vaccination was not able to induce antibodies that could neutralize the rabies virus infection completely. Therefore, she conducted a study to determine the effectiveness of local isolates as vaccine seeds to prevent the spread of rabies in Indonesia.
An epitope is part of an antigen that is still capable of inducing antibody synthesis to fight disease. Epitope-based vaccines have often been used for vaccinations because they have many advantages; affordable, immunogenic and can reduce the effects after vaccination (Ahmed et al., 2017).
“Epitope analysis that stimulates the work of T and B lymphocyte cells can be used to select isolates that can be used as seed candidate vaccines against rabies. Therefore, the analysis of T and B lymphocyte epitope cells is essential in determining local strains to be used as seed vaccines against disease in Indonesia, “he explained.
In his research, Jola used the brains of dogs infected with rabies as samples. A total of 9 samples were collected from Sulawesi (Balai Besar Veterinary Maros-Sulawesi), Bali (Balai Besar Veteriner Denpasar), and Sumatra (Balai Veterinary Research and Investigation Regional II Bukittinggi-Sumatra). Samples collected from each island are three samples. Each sample is processed into suspense with a concentration of 10% then processed for RNA extraction. Extracted RNA is processed for DNA synthesis through Reverse-Transcriptase.
“The results of the amplification showed that the sample isolated was a rabies virus. It indicated by the presence of nine examples parallel to the 1000 bp marker, “she said.
The results of the amplification were purified and processed into the sequencing stage to get the full sequence of the amplified region. Based on epitope predictions, two samples isolated from Sumatra (RABV_533 and RABV_438) had more epitope numbers than the other samples.
“Epitope is part of antigens that can still induce immunity, so the use of epitope from local isolates as a vaccine subunit can be one way to tackle the spread of rabies in Indonesia,” said Jola.
Until now, further research related to the work of the two vaccine candidates in inducing immunity against rabies infection is still being developed to reduce the spread of the rabies virus in Indonesia effectively. (*)
Author: Zanna Afia
Editor: Khefti Al Mawalia
Rahmahani, Jola, et al. 2019. Prediction According to Glycoprotein Encoding Gene of Rabies Virus Local Isolates as Vaccine Candidate against Circulating Rabies Virus in Indonesia. The Indian Veterinary Journal. Vol 96-(09). p. 14–16.