FAMILY ERRONACEAE 



1263 



* Serological relationships : Serum from 

 recovered cases neutralizes the virus. 



Immunological relationships : Specific 

 immunity follows attack of the disease. 



Filterability : Passes Chamberland L2 

 filter. 



Literature :Durandetal., Compt. rend. 

 Acad. Sci., Paris, 203, 1936, 830-832, 957- 

 959, 1032-1034; Arch. Inst. Pasteur de 

 Tunis, 26, 1937, 213-227; 228-249; 27, 

 1938, 7-17. 



Genus III. Formido gen. nov. 



Viruses of the Rabies Group, inducing diseases characterized by involvement of 

 the nervous system only. Generic name from Latin /ornnV/o, a frightful thing. 

 The type and only recognized species is Formido inexorabilis spec. nov. 



1. Formido inexorabilis spec. nor. 

 From Latin inexorabilis, implacable. 



Common name : Rabies virus. 



Hosts: CAN I DAE — Canis familiaris 

 L., dog. FELIDAE—Felis catus L., do- 

 mestic cat ; F. negripes, black-footed cat ; 

 F. ocreata, wild cat. HOMINIDAE— 

 Homo sapiens L., man. MUSTELI- 

 DAE — Icionyx orangiae, polecat. SCI- 

 URIDAE — Geosciurus capensis, ground 

 squirrel. V IVERRIDAE—Cynictis 



penicillata, yellow mongoose (yellow 

 meercat) ; Genetta felina (Thunb.), genet 

 cat; Myonax pulverulentus , small, grey 

 mongoose; Suricata suricatta, Cape suri- 

 cate or common meercat. Cattle, sheep, 

 pig, horse , wolf. Cynalopex chama, silver 

 jackal. Phyllostoma superciliatum, vam- 

 pire bat; Desmodus rufus, vampire bat; 

 Artibens planirostris trinitatis, fruit-eat- 

 ing bat. Experimentally, also Mus mus- 

 culus L., white mouse ; Peromyscus polio- 

 notus polionotus (Wagner), white-footed 

 mouse; tissue cultures of 5 or 6-day -old 

 rat- or mouse-embryo brain; chick em- 

 bryo (allantois not regularlj^ infected, 

 but virus regularly reaches brain of em- 

 bryo without injuring it ; chick may hatch 

 with titer of 1:100 or 1:1000 in brain). 

 Chicken; mouse hawk (iJuieo vulgaris); pi- 

 geon, owl, goose; stork (Ciconia ciconia); 

 pheasant {Diardigallus diardi B.P.). 



Insusceptible species : Reptiles, fish. 



No mammal is known to be insusceptible. 



Geographical distribution : Almost 



world-wide ; absent only from relatively 



isolated countries or communities. 



Induced disease : In dog, after a short 



incubation period (generally less than 10 

 daj's) altered behavior, hiding, lack of 

 obedience, perverted appetite leading to 

 ingestion of straw, paper, earth, and other 

 unaccustomed materials ; excitement, un- 

 provoked biting (which may transmit the 

 virus to new hosts), aimless wandering, 

 excess salivation, progressive inability to 

 swallow, alteration of bark to characteris- 

 tic high pitched tone; staggering, paresis 

 of hindquarters tending toward paralysis 

 and involvement of anterior parts of the 

 body; paralysis of lower jaw, muscular 

 spasms, marked emaciation, death except 

 perhaps in rare instances. In man, after 

 a relatively long incubation period de- 

 pending on site of implantation (perhaps 

 27 to 64 days), a uniformly fatal disease, 

 characterized by altered behavior, in- 

 creased excitability, thirst, pharyngeal 

 spasm with progressive inability to swal- 

 low, labored and noisy respiration, death 

 in 3 or 4 days after onset, with or without 

 paroxysm. In sheep, increased sexual 

 desire ; tendency to pull wool from other 

 sheep or themselves; light butting, in- 

 creasing until some ewes, after violent 

 exercise, appear to faint; prostration 

 within 1 to 4 days ; death within 2 days 

 from onset of locomotory paralysis. In 

 mouse, experimentally, by intracerebral 

 inoculation, apathy, sluggishness, rough- 

 ening of hair, tremor, convulsions, pros- 

 tration, death; sometimes flaccid 

 paralysis of hind legs before death. 



Transmission: Usually by bite of dog 

 or some closely related animal ; occa- 

 sionally by bites of cats ; rarely by bites 



