9. small animal med- salmon poisoning, rocky mountain SF,

what is salmon poisoning disease?

helminth-borne rickettsial disease of dogs in the western slopes of the cascades

what is the causative agent of salmon poisoning?

neorickettsia helminthoeca

what is elokomin fluke fever?

likely another rickettsial strain with high morbidity and low mortality

wider host range than just dogs

what is the vector for salmon poisoning?

trematode nanophyetus salmincola

what are 4 hosts of salmon poisoning disease?

snail, fish, mammals or birds

how do dogs become infected with salmon poisoning disease?

infection by eating fish with metacercaria

do cats get salmon poisoning disease?

cats do not get rickettsial disease, but eating fish with metacercaria may cause mild diarrhea (if anything)

what is the incubation period of salmon poisoning disease?

1 week (as long as a month)

what are the clinical signs of salmon poisoning disease?

-high fever (normalizes in 4-8 days)

-anorexia

-marked weight loss

-progressive vomiting and diarrhea

-bloody diarrhea at the end

-thirst

when can death from salmon poisoning occur?

7-10 days

what is the incubation period of elokomin fluke fever?

5-12 days

how long does fever last in elokomin fluke fever? what is the mortality rate?

fever plateaus in 4-7 days

lower mortality rate than salmon poisoning

what laboratory changes are seen with salmon poisoning disease?

-non-specific

-thrombocytopenia (88%)

-eosinophilia (77%)

how is salmon poisoning disease diagnosed via fecal?

look for trematode eggs in feces via direct smear/sedimentation

will see eggs in feces 5-8 days post infection

how is salmon poisoning disease diagnosed via FNA?

FNA lymph nodes to find rickettsial bodies in mononuclear cells

what is the therapy for salmon poisoning disease?

-in hospital

-supportive

-antibiotics (tetracyclines)

-praziquantel

how is salmon poisoning disease prevented?

avoid raw fish (metacercaria are viable for months)

what is the causative agent of rocky mountain spotted fever (RMSF)?

rickettsia rickettsii

what are the vectors of rocky mountain spotted fever in the US?

dermacentor andersonii

dermacentor variabilis

amblyomma americanum

rhipicephalus linnaei

what is the epidemiology of RMSF?

present throughout the US, most common in the southeast US (due to distribution of the vector)

RMSF is an acute disease, and occurs april thru september

how is RMSF transmitted?

transovarial transmission may occur

-thru bites of ticks

what is the time from attachment of ticks to transmission of RMSF?

d. variabilis: less than 4 hours

d. andersonii: unknown (not 24 to 48 hours)

a. aeurolatum: 10 hours (10 minutes if feeding is interrupted)

where does RMSF replicate in dogs?

endothelial cells

what are the consequences of RMSF replicating in the endothelial cells of dogs?

-widespread necrotizing vasculitis

-platelet aggregation and DIC

-multiple organ damage

what is the incubation period of RMSF in dogs?

2-14 days

frequently, the tick has left the dog before the onset of clinical signs

what are the clinical findings of subclinical RMSF?

subclinical dz occurs in most dogs, may have mild asymptomatic thrombocytopenia

what are the clinical findings for acute RMSF?

-anorexia and fever

-neurologic signs

-myalgia, athralgia

-generalized lymphadenopathy

-peripheral edema (face and limbs)

-arrhythmias

-petechiae and ecchymoses in 20% of dogs

-renal failure

-pulmonary edema

-death

what laboratory changes are seen with RMSF?

-leukocytosis with left shift, monocytosis

-thrombocytopenia (from consumption)

-DIC

-organ failure

how is RMSF diagnosed?

clinical signs and serology

-serum titers may be negative at presentation (will rise 2-3 weeks post-exposure)

what serum titer (+ clinical signs) is indicative of an active RMSF infection?

titers over 1:1024 or 4-fold increase in IgG

why should you not rely solely on serology to diagnose RMSF?

-seropositivity can be much higher than incidence of disease

-subclinical infection is common

-reactivity may occur

what is the therapy for RMSF?

antibiotics: doxycycline, enrofloxacin

supportive therapy (treat complications)

how long after starting therapy for RMSF should clinical signs and platelet count improve?

in 48 hours

what is the prognosis of RMSF with therapy?

fair

how is RMSF prevented?

-strict tick control

-dogs may increase chances of human exposure to RMSF (by bringing ticks into human environment)

how can people be infected with RMSF?

by removing ticks from dogs with their hands (if squeezing tick too hard- people are very sensitive to infection)