Zoonotic DiseasesZoonotic Diseases(Disease caused by Animals(Disease caused by Animals))

A zoonosis is any infectious disease that is transmitted by a vector from non-human animals, both wild and domestic, to humans or from humans to non-human animals (Reverse Zoonoses)

Types of ZoonosesTypes of Zoonoses• BACTERIAL DISEASES BACTERIAL DISEASES PARASITIC DISEASES PARASITIC DISEASES

BrucellosisBrucellosis Balisascaris procyonisBalisascaris procyonisBubonic PlaqueBubonic PlaqueLeptospirosisLeptospirosis

PsittacosisPsittacosis PROTOZOAN DISEASESPROTOZOAN DISEASESSalmonellosisSalmonellosis GiardiasisGiardiasisTetanusTetanus ToxoplasmosisToxoplasmosisTularemiaTularemia

• MYCOTIC DISEASESMYCOTIC DISEASES TICK BORNE DISEASESTICK BORNE DISEASES Aspergillosis Aspergillosis Lyme DiseaseLyme Disease

HistoplasmosisHistoplasmosis Rocky Mountain Spotted Rocky Mountain Spotted FeverFever

• VIRAL DISEASESVIRAL DISEASESRabiesRabies

TULAREMIATULAREMIA Pahvant Valley plaguePahvant Valley plague, , rabbit feverrabbit fever, , deer fly feverdeer fly fever, ,

Ohara's feverOhara's fever FrancisellaFrancisella tularensis tularensis ( (ggram-negativeram-negative, , non-motilenon-motile

coccobacilluscoccobacillus ) ) primary primary vectorsvectors are are ticksticks and and deer fliesdeer flies RodentsRodents, rabbits, and hares - , rabbits, and hares - reservoir hostsreservoir hosts biting flies , direct contact with contaminated animals biting flies , direct contact with contaminated animals

or material,or material, by ingestion of poorly cooked flesh of infected by ingestion of poorly cooked flesh of infected

animals or contaminated water, animals or contaminated water,

Clinical ManifestationsClinical Manifestations Depending on the site of infectionDepending on the site of infection

UlceroglandularUlceroglandular - local ulceration at a site of infection - local ulceration at a site of infection

Oropharyngeal -Oropharyngeal -Sores in the mouth and throat, as well as Sores in the mouth and throat, as well as abdominal abdominal painpain, nausea and vomiting, ulcers in the intestine, , nausea and vomiting, ulcers in the intestine, intestinal bleeding, and diarrhea may all occur. intestinal bleeding, and diarrhea may all occur.

pneumonic- pneumonic-

OculoglandularOculoglandular - swollen eyelids, conjunctivitis, swollen lymph - swollen eyelids, conjunctivitis, swollen lymph nodes, and ulcers on the conjunctivae. nodes, and ulcers on the conjunctivae.

TyphoidalTyphoidal - - swelling of lymph glands with continuously high swelling of lymph glands with continuously high fever, terrible headache, and confusion.fever, terrible headache, and confusion.

The illness may result in a severely low blood pressure, with signs of The illness may result in a severely low blood pressure, with signs of poor blood flow to the major organs (shock). poor blood flow to the major organs (shock).

IP 1 – 14 daysIP 1 – 14 days Susceptible persons - clinical signs include fever, Susceptible persons - clinical signs include fever,

lethargy, anorexia, signs of septicemia, and lethargy, anorexia, signs of septicemia, and possibly death possibly death

SubclinicalSubclinical infections are common and animals infections are common and animals often develop specific antibodies to the organism. often develop specific antibodies to the organism.

Fever is moderate or very high and tularemia Fever is moderate or very high and tularemia bacillus can be isolated from blood cultures at this bacillus can be isolated from blood cultures at this stage .stage .

Face and eyes redden and become inflammed Face and eyes redden and become inflammed Inflammation spreads to the lymph nodes - enlarge Inflammation spreads to the lymph nodes - enlarge

and may suppurate (mimicking bubonic plague). and may suppurate (mimicking bubonic plague). Lymph node involvement - accompanied by high Lymph node involvement - accompanied by high

fever.fever. Death occurs in less than 1% if therapy is initiated Death occurs in less than 1% if therapy is initiated

promptly promptly

DiagnosisDiagnosis• Skin lesions samples – stainingSkin lesions samples – staining• Buffered Charcoal and Yeast Extract (BCYE)Buffered Charcoal and Yeast Extract (BCYE)

• Serological tests for detection of antibodies Serological tests for detection of antibodies

Treatment Treatment Streptomycin - muscle Streptomycin - muscle gentamicin - Injected in muscle or through gentamicin - Injected in muscle or through

a needle in the veina needle in the vein Doxycycline for 2–3 weeks Doxycycline for 2–3 weeks Live vaccine is a available but restricted Live vaccine is a available but restricted

due to high riskdue to high risk

PreventionPrevention• avoiding areas known to harbor ticks avoiding areas known to harbor ticks

and flies and flies • Hunters should wear gloves when Hunters should wear gloves when

skinning animals or preparing meat skinning animals or preparing meat

Yersinia pestisYersinia pestis – Gr negative rod shape, – Gr negative rod shape, anaerobeanaerobe

Flea borneFlea borne enters through the skin and travels enters through the skin and travels

through the lymhaticsthrough the lymhatics

PUBONIC PLAQUEPUBONIC PLAQUE

Pathology and transmissionPathology and transmission

infection of the lymphatic system, usually infection of the lymphatic system, usually resulting from the bite of an infected flea, resulting from the bite of an infected flea, XenopsylaXenopsyla cheopischeopis (the rat flea ) (the rat flea )

fleas often found on rodents (rats and mice )fleas often found on rodents (rats and mice ) bacteria form bacteria form aggregatesaggregates in the gut of infected in the gut of infected

fleas , results in the flea fleas , results in the flea regurgitating ingested regurgitating ingested bloodblood, which is infected into the bite site of a , which is infected into the bite site of a rodent or human host rodent or human host

bacteria rapidly spread to the lymph nodes and bacteria rapidly spread to the lymph nodes and multiply multiply

Y. pestisY. pestis resist phagocytosis and multiply in resist phagocytosis and multiply in phagocytes and kill themphagocytes and kill them

the lymph nodes can hemorrhage and become the lymph nodes can hemorrhage and become swollen and necroticswollen and necrotic

Bubonic plaque changed into septicemic Bubonic plaque changed into septicemic plaqueplaque

Pneumonic plaque- spread to plaquePneumonic plaque- spread to plaque Organisms can spreads by droplets (sneezing / Organisms can spreads by droplets (sneezing /

coughing)coughing)

SymptomsSymptoms

Bubonic plaqueBubonic plaque• painful, swollen lymph glands (buboes )painful, swollen lymph glands (buboes )• Commonly found in groin, armpits & neckCommonly found in groin, armpits & neck• First stage of series illnessFirst stage of series illness

pneumonic and septicemic pneumonic and septicemic • patient with the bubonic plague developed patient with the bubonic plague developed

pneumonia or blood poisoning .pneumonia or blood poisoning .• Pneumonic plaque induces coughingPneumonic plaque induces coughing

Symptoms like red spots which turn black laterSymptoms like red spots which turn black later

heavy breathing, heavy breathing, continuous blood vomiting, continuous blood vomiting, urination of blood, aching limbs, urination of blood, aching limbs,

coughing, and terrible pain. coughing, and terrible pain. pain caused by the actual decaying, pain caused by the actual decaying,

or decomposing, of the skin while the or decomposing, of the skin while the person is still aliveperson is still alive

PreventionPrevention• Active ImmunizationActive Immunization• Avoid contactwith infected persons/animalsAvoid contactwith infected persons/animals

TreatmentTreatment• Aminoglycosides streptomycinAminoglycosides streptomycin• DoxycylineDoxycyline• GentamycinGentamycin• Fluroquinolone ciprofloxainFluroquinolone ciprofloxain

PsittacosisPsittacosis

parrot diseaseparrot disease, , parrot feverparrot fever, and , and ornithosisornithosis

Chlamydophila psittaci – gram Chlamydophila psittaci – gram negativenegative

Spreads from parrots, pigeons, hens, Spreads from parrots, pigeons, hens, ducksducks

Infection in birdsInfection in birds Infection in birds - avian chlamydiosis Infection in birds - avian chlamydiosis Shed bacteria in feces and secretion viable Shed bacteria in feces and secretion viable

for monthsfor months Certain strains quiescent until any stress Certain strains quiescent until any stress

conditions arisedconditions arised Symptoms Symptoms

• Infection is systemic & apparent Infection is systemic & apparent • Infection is severe, acute or chronic with Infection is severe, acute or chronic with

intermittent shedding intermittent shedding • inflamed eyes, difficulty in breathing, watery inflamed eyes, difficulty in breathing, watery

droppings and green urates droppings and green urates

Infection spreads throughInfection spreads through• Droppings, feathers, eggsDroppings, feathers, eggs• infect mucosal epithelial cells and infect mucosal epithelial cells and

macrophages of the respiratory tract macrophages of the respiratory tract • Septecimia develops and localises in Septecimia develops and localises in

epithelial cells and Mepithelial cells and MØ’s of Ø’s of organs, organs, conjunctiva, and gastrointestinal tract conjunctiva, and gastrointestinal tract

Various serovars existVarious serovars exist• Serovar A- humans, mammals, tortoisesSerovar A- humans, mammals, tortoises• Serovar B- pigeonsSerovar B- pigeons• Serovar C & D- slaughter workers & Serovar C & D- slaughter workers &

close contact personsclose contact persons• Serovar E – not specificSerovar E – not specific

Disease can be diagnosedDisease can be diagnosed• Through symptomsThrough symptoms• Confirmed by antigen & antibody reaction Confirmed by antigen & antibody reaction • PCR based testsPCR based tests• false negatives are possible , so combination of false negatives are possible , so combination of

clinical and lab tests is recommended clinical and lab tests is recommended • Infection is fatal & kills the bird in 3 weeks.Infection is fatal & kills the bird in 3 weeks.

Treatment.Treatment.• Doxycyline and Tetracycline in water/ Doxycyline and Tetracycline in water/

injectionsinjections

Infection in HumansInfection in Humans

IP 5 -14 daysIP 5 -14 days In apparent to severe illness – pneumoniaIn apparent to severe illness – pneumonia Typhoid in Initial stagesTyphoid in Initial stages prostrating high prostrating high fever, arthralgias, fever, arthralgias,

diarrhoea, conjuctivitis, epistaxis and diarrhoea, conjuctivitis, epistaxis and leukopenialeukopenia

Rose spots occur – Horder’s spotsRose spots occur – Horder’s spots Spleenomegaly,Spleenomegaly, Severe head ache – indication of Severe head ache – indication of

meningitismeningitis

During 2 weekDuring 2 week• Pneumonia with continuous high fevers, Pneumonia with continuous high fevers,

cough and dyspnoea cough and dyspnoea • patchy infiltrates or a diffuse whiteout of patchy infiltrates or a diffuse whiteout of

lung fields lung fields • Blood show thrombocytopenia and liver Blood show thrombocytopenia and liver

enzymesenzymes• Myocarditis, arthritis, keratoconjuctivitisMyocarditis, arthritis, keratoconjuctivitis

Infection spreads toInfection spreads to• Pet holders, pet shop owners, veterinarians , Pet holders, pet shop owners, veterinarians ,

zoo keeperszoo keepers Diagnosis made by Diagnosis made by

• Microbial cultures – resiratory secretionMicrobial cultures – resiratory secretion• Four fold increase in Ab titresFour fold increase in Ab titres

TreatmentTreatment• Tetracycline & ChlorampenicolTetracycline & Chlorampenicol• Oral doxycyline, tetracycline hydrocholride, Oral doxycyline, tetracycline hydrocholride,

chlorampenicol palmitatechlorampenicol palmitate