The National Institute of High Security Animal Disease (NIHSAD) has found that the 2000 pigs in Assam died from African swine fever.
The NIHSAD stated that a total of 17 morbid tissue samples collected from Biswanath, Sivasagar, Kamrup (M), Jorhat and Dhemaji districts of Assam with unusual mortality in pigs were sent by NERD, Guwahati, Assam. In addition, 62 samples (51 sera, 1 whole blood, 3 tissue samples and 7 nasal swabs) collected from East Siang and Papum Pare districts of Arunachal Pradesh were sent by the Dept. of Animal Husbandry.
These samples were received at ICAR NIHSAD, Bhopal on April 26th, 2020 for laboratory diagnosis of African Swine Fever (ASF).
The test was carried out as per the protocol described in the OIE terrestrial manual 2019 using primers and probes (King et al., 2003) targeting VP72 gene of ASF virus. Commercial indirect ELISA (IDVet ID Screen) was used to screen serum samples for ASFV antibodies.
During the nucleotide sequencing, ASF virus genes encoding VP72 (278 bp), CVR within the 8602L gene (665 bp) and E183L-gene (676 bp) encoding the p54 protein were amplified by conventional PCR from representative ASFV real time PCR positive samples and were confirmed by nucleotide sequencing.
ASF virus isolation from selected ASFV genome positive samples is under progress as per the protocol described in the OIE terrestrial manual 2019. Real time RT-PCR was carried out for differential diagnosis of classical swine fever.
In the end results, the NIHSAD found that all 17 tissue samples from Assam were positive for ASFV genome by real time PCR and nucleotide sequencing analysis.
Eleven (4 sera & 7 nasal swabs) out of 62 samples from Arunachal Pradesh were positive for ASFV genome by real time PCR and nucleotide sequencing analysis. All serum samples from Arunachal Pradesh were tested negative for ASFV antibodies by ELISA.
On the basis of real time PCR results and nucleotide sequence analysis of three different ASFV target genomic regions, the presence of African Swine Fever Virus is confirmed in the suspected pig samples from Assam and Arunachal Pradesh.
There have been several pig deaths reported in Sivasagar, Lakhimpur, Dibrugarh, Jorhat, Dhemaji and Biswanath. The disease is feared to have come into the state from China and in precautions, the sale of pork has been banned in several places in the state.
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