Rabies immune status of raccoon dogs residing in areas where rabies bait vaccine has been distributed

Abstract

Since 2000, large amounts of rabies bait vaccine have been distributed in two provinces where raccoon dog-mediated rabies has occurred. A total of 146 raccoon dogs were caught in Gangwon and Gyeonggi Provinces from January 2017 to June 2018, and raccoon dog blood samples were collected. Of the 146 raccoon dogs, 13.7% (20/146) had rabies antibodies. In Gyeonggi and Gangwon provinces, the rate of rabies antibody was 8.5% (5/59) and 17.2% (15/87), respectively. Considering these results, it would be desirable to improve the distribution method or use a new bait vaccine to prevent animal rabies in South Korea.

The Presence of Rabies Virus-Neutralizing Antibody in Wild Boars (Sus scrofa), a Non-Target Bait Vaccine Animal in Korea

“…In 2012, VNAs against RABV were detected in 20 of 50 (40%) raccoon dog serum samples from Gangwon, Gyeonggi, and Seoul [ 15 ]. From January 2017 to June 2018, 13.7% (20/146) of the serum samples from raccoon dogs in Gangwon (17.2% (15/87)) and Gyeonggi (8.5% (5/59)) were rabies-VNA positive [ 16 ]. As mentioned above, the prevalence of anti-rabies antibodies has been investigated in the raccoon dog, which is the target wild animal in Korea [ 15 , 16 ].…”

“…From January 2017 to June 2018, 13.7% (20/146) of the serum samples from raccoon dogs in Gangwon (17.2% (15/87)) and Gyeonggi (8.5% (5/59)) were rabies-VNA positive [ 16 ]. As mentioned above, the prevalence of anti-rabies antibodies has been investigated in the raccoon dog, which is the target wild animal in Korea [ 15 , 16 ]. However, this study is the first to evaluate the prevalence of anti-rabies antibodies in wild boars from multiple Korean provinces.…”

“…In this study, the VNA titer was ≥ 0.5 IU/mL in 59 of 579 (10.2%) wild-boar samples obtained between August 2017 and July 2018 nationwide. In the bait-vaccinated areas of Gangwon and Gyeonggi, 18.3% (20/109) the wild-boar samples were seropositive, and the rate did not differ significantly from recent rates (13.7%, 20/146) reported for raccoon dogs, the target animals ( p = 0.3845, Fisher’s exact test) [ 16 ]. As in the case of raccoon dogs, the seropositive rate in wild boars was also higher in Gangwon (19.6% (11/56)) than in Gyeonggi (17.0% (9/53)), probably because more bait vaccine was distributed in Gangwon than in Gyeonggi [ 16 ].…”

“…The rabies bait vaccine has been distributed for raccoon dogs in Korea for 20 years and the target animals have been tested for antibody positivity [ 15 , 16 ]. However, rabies antibody positivity, which reflects the rate of bait vaccine consumption, has never been investigated in non-target wild animals in Korea.…”

“…However, rabies antibody positivity, which reflects the rate of bait vaccine consumption, has never been investigated in non-target wild animals in Korea. Therefore, this study investigated the rate of antibody positivity in wild boars ( Sus scrofa ), which are likely the main competitors for the bait vaccine in Korea; it then compared this rate with the reported positive rates in raccoon dogs [ 16 ].…”