Genetic Diversity, Evolutionary Dynamics, and Pathogenicity of Ferret Badger Rabies Virus Variants in Mainland China, 2008–2018

Abstract

In contrast to dog-associated human rabies cases decline year by year due to the rabies vaccination coverage rates increase in China, ferret badger (FB, Melogale moschata)-associated human rabies cases emerged in the 1990s, and are now an increasingly recognized problem in southeast China. To investigate epidemiology, temporal evolution dynamics, transmission characterization, and pathogenicity of FB-associated rabies viruses (RABVs), from 2008 to 2018, we collected 3,622 FB brain samples in Jiangxi and Zhejiang Province, and detected 112 RABV isolates. Four FB-related lineages were identified by phylogenetic analysis (lineages A–D), the estimated Times to Most Recent Common Ancestor were 1941, 1990, 1937, and 1997 for lineages A–D, respectively. Furthermore, although no FB-associated human rabies case has been reported there apart from Wuyuan area, FB-RABV isolates are mainly distributed in Jiangxi Province. Pathogenicity of FB-RABVs was assessed using peripheral inoculation in mice and in beagles with masseter muscles, mortality-rates ranging from 20 to 100% in mice and 0 to 20% in beagles in the groups infected with the various isolates. Screening of sera from humans with FB bites and no post-exposure prophylaxis to rabies revealed that five of nine were positive for neutralizing antibodies of RABV. All the results above indicated that FB-RABV variants caused a lesser pathogenicity in mice, beagles, and even humans. Vaccination in mice suggests that inactivated vaccine or recombinant subunit vaccine products can be used to control FB-associated rabies, however, oral vaccines for stray dogs and wildlife need to be developed and licensed in China urgently.

A Global Perspective on Oral Vaccination of Wildlife Against Rabies

“…Most concentration has been focused upon only a few key mesocarnivores, such as coyotes, foxes, jackals, raccoons, and raccoon dogs, whereas other taxa await similar application. For example, ferret badgers are important reservoirs in Asia (Shih et al 2018;Miao et al 2023). Several other species may maintain rabies in Africa, including the yellow mongoose (C. penicillata), slender mongoose (Galerella sanguinea), African civet (Civettictis civetta), bat-eared fox, meerkat (Suricata suricatta), aardwolf (Proteles cristatus), spotted hyena (Crocuta crocuta), and others (Sabeta et al 2020;Binkley et al 2022;Koeppel et al 2022b).…”

Molecular analysis and geographic distribution of the recent Indonesian rabies virus

“…[1,2]. Most human deaths from rabies have occurred in Asia and Africa at 56% and 44%, respectively [3][4][5]. Global human deaths due to rabid dogs are estimated at more than 55,000 [4], with an annual reported incidence of 30,000 in Asia and 23,000 in Africa [1].…”

“…In Asia, several countries have endemic rabies, such as India, Bangladesh, Philippines, Thailand, Indonesia, Myanmar, China (mainland China), and Korea [5][6][7]. Several districts and countries, including Hong Kong, Taiwan, Japan, and Malaysia, have been declared free of rabies, but sporadically, there are still cases of rabies in both animals and humans [6,8].…”