Can Rabies Infection have an Abortive Phase? Need for Further Evidence to Understand Rabies Epidemiology

Abstract

Rabies is known to mankind for more than 4000 years; one of the oldest known zoonoses with 100% fatality. It is well known that the rabies virus (RABV) can evade innate immunity.1 RABV has evolved diverse strategies for immune evasion as “accessory” functions of the P, N, and M proteins, although many of these studies have used in vitro approaches focusing on the molecular biology of immune evasion.2 However many in vivo studies have shown rabies antibodies in humans3,4 cows & buffaloes,5 dogs,6 and bats7 without a rabies vaccination. Abortive vampire bat rabies in Peruvian peri-domestic livestock has been reported.8 Another study observed an inverse relationship between the presence of lyssavirus antigens and levels of rabies antibodies in unvaccinated dogs that underscores the notion of immune evasion following lyssavirus infection.9 In another study by Vaughn et al10, thirteen groups totaling 117 dogs were inoculated with the rabies virus and 54 dogs developed fatal rabies (49%) pointing out abortive clinical infection after actual virus inoculation.