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ies
Rabies
R abies is a viral infectio n o f wild and d o m estic m am m als, transm itted to hum ans by
the saliva o f infected anim als thro ugh bites, scratches o r lick s o n bro k en sk in o r m uco us
m em branes. A ny m am m al can transm it rabies, but the great m ajo rity o f hum an cases
are d ue to d o g bites.
O nce sy m p to m s d evelo p , rabies p resents as a fatal encep halitis. There is no curative
treatm ent; care is p alliative.
B efo re sy m p to m atic d isease has d evelo p ed , rabies can effectively be p revented by p o st-
exp o sure p ro p hy laxis.
Clinical features
– The incubatio n p erio d averages 2 0 to 9 0 d ay s fro m exp o sure (7 5 % o f p atients), but
can be sho rter (in severe exp o sure, i.e. bites to face, head and hand s, m ultip le bites),
o r lo nger (2 0 % o f p atients d evelo p sy m p to m s between 9 0 d ay s and 1 y ear, and
5%
m o re than 1 y ear after exp o sure).
– P ro d ro m al p h ase: itching o r p araesth esiae aro und th e site o f exp o sure, and no n-
sp ecific sy m p to m s (m alaise, fever, etc.).
– N euro lo gic p hase:
• F urio us fo rm : p sy cho m o to r agitatio n o r h y d ro p ho bia (thro at sp asm s and p anic,
triggered by attem p ting to d rink o r sight/ so und / to uch o f water) and aero p ho bia
(sim ilar resp o nse to a d raft o f air) ; so m etim es seiz ures. The p atient is calm and
lucid between ep iso d es.
• P araly tic fo rm ( less co m m o n, 2 0 % o f cases) : p ro gressive ascend ing p araly sis
resem bling G uillain-B arré sy nd ro m e.
D iagno sis is o ften d ifficult: th ere m ay be no h isto ry o f scratch o r bite ( exp o sure
thro ugh lick ing) o r wo und s m ay h ave h ealed ; a reliable h isto ry m ay be d ifficult to
o btain.
Post-exposure prophylaxis
Risk of rabies virus infection: definition of exposure categories (WHO)
Category I C o ntact with anim al, o r lick s o n intact sk in No exposure
Category II Minor exposure
N ibbles o n exp o sed sk in
Category III M ino r bite(s) o r scratch(es) witho ut bleed ing
Transd erm al bite(s) o r scratch(es) Severe exposure
C o ntam inatioLnicokfsmo uncobruoskmenemsk binranes by anim al‟s
E sxapliovas(ulircek tso) bat
1
P o st-exp o sure p ro p hy laxis is carried o ut fo r C atego ry II and II I exp o sures.
In the case of direct contact with bats, check national recommendations.
1
194
Rabies
R abies is a viral infectio n o f wild and d o m estic m am m als, transm itted to hum ans by
the saliva o f infected anim als thro ugh bites, scratches o r lick s o n bro k en sk in o r m uco us
m em branes. A ny m am m al can transm it rabies, but the great m ajo rity o f hum an cases
are d ue to d o g bites.
O nce sy m p to m s d evelo p , rabies p resents as a fatal encep halitis. There is no curative
treatm ent; care is p alliative.
B efo re sy m p to m atic d isease has d evelo p ed , rabies can effectively be p revented by p o st-
exp o sure p ro p hy laxis.
Clinical features
– The incubatio n p erio d averages 2 0 to 9 0 d ay s fro m exp o sure (7 5 % o f p atients), but
can be sho rter (in severe exp o sure, i.e. bites to face, head and hand s, m ultip le bites),
o r lo nger (2 0 % o f p atients d evelo p sy m p to m s between 9 0 d ay s and 1 y ear, and
5%
m o re than 1 y ear after exp o sure).
– P ro d ro m al p h ase: itching o r p araesth esiae aro und th e site o f exp o sure, and no n-
sp ecific sy m p to m s (m alaise, fever, etc.).
– N euro lo gic p hase:
• F urio us fo rm : p sy cho m o to r agitatio n o r h y d ro p ho bia (thro at sp asm s and p anic,
triggered by attem p ting to d rink o r sight/ so und / to uch o f water) and aero p ho bia
(sim ilar resp o nse to a d raft o f air) ; so m etim es seiz ures. The p atient is calm and
lucid between ep iso d es.
• P araly tic fo rm ( less co m m o n, 2 0 % o f cases) : p ro gressive ascend ing p araly sis
resem bling G uillain-B arré sy nd ro m e.
D iagno sis is o ften d ifficult: th ere m ay be no h isto ry o f scratch o r bite ( exp o sure
thro ugh lick ing) o r wo und s m ay h ave h ealed ; a reliable h isto ry m ay be d ifficult to
o btain.
Post-exposure prophylaxis
Risk of rabies virus infection: definition of exposure categories (WHO)
Category I C o ntact with anim al, o r lick s o n intact sk in No exposure
Category II Minor exposure
N ibbles o n exp o sed sk in
Category III M ino r bite(s) o r scratch(es) witho ut bleed ing
Transd erm al bite(s) o r scratch(es) Severe exposure
C o ntam inatioLnicokfsmo uncobruoskmenemsk binranes by anim al‟s
E sxapliovas(ulircek tso) bat
1
P o st-exp o sure p ro p hy laxis is carried o ut fo r C atego ry II and II I exp o sures.
In the case of direct contact with bats, check national recommendations.
1
194
