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ZOONOSES. Suzanne R. Jenkins, VMD, MPH, Dpl. ACVPM Office of Epidemiology Virginia Department of Health. Introduction. Focus on prevention Hundreds of zoonotic diseases Using method of transmission as outline, highlight some more common zoonotic diseases as examples
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ZOONOSES Suzanne R. Jenkins, VMD, MPH, Dpl. ACVPM Office of Epidemiology Virginia Department of Health
Introduction • Focus on prevention • Hundreds of zoonotic diseases • Using method of transmission as outline, highlight some more common zoonotic diseases as examples • Fecal Oral – bacterial, parasitic • Inhalation • Direct Contact • Vector Borne – mosquitoes and ticks • Penetrating Wounds
Animal Benefits • Food, fiber, leather • Guards and hunters • Recreation/Entertainment • Companionship • Improve physical and mental health • Must weigh risks/benefits for immunocompromised, children, the elderly
Fecal-Oral Transmission • Organism passed in feces and then ingested • Human to Human • Animal to Human • Through food or water • May or may not cause disease in animals
Fecal-Oral Bacterial Diseases Common examples Organism Salmonella spp. (> 1000 serotypes) Campylobacter E. coli O157-H7 Prevention Good hygiene Good hygiene Good hygiene Other issues Eggs, reptiles Raw milk Undercooked ground beef
Clinical Features • Incubation – hours to days • GI signs – diarrhea (can be bloody), cramps, vomiting • Fever • Usually self limiting – days to weeks • Salmonella – sepsis, especially old/young • E. coli 0157-H7 – hemolytic uremic syndrome
Foodborne Prevention • Do not eat raw or undercooked eggs, poultry or meat • Do not consume raw/unpasteurized milk or other dairy products • Produce should be thoroughly washed • Avoided cross-contamination of foods • wash hands, utensils, cutting boards, counters
Pet Associated Prevention • Wash hands after handling animals and cleaning up feces • Prevent young children from exposure to pets with diarrhea • Use special care with puppies from animal shelters and crowded kennels • Make sure petting zoos and other animal exhibits provide handwashing facilities
Reptile-associated Salmonella • Approximately 93,000 (7%) cases per year of Salmonella spp. infections are attributable to pet reptile or amphibian contact • increase in human isolates of rare Salmonella serotypes, such as Java, Marina, Stanley, Poona, and Chameleon • During 1989-1998, 516 (24%) of 2150 Salmonella isolates with reptile-associated serotypes were from children aged less than 4 years
Case Reports • Infants being cared for in homes with iguanas • No direct contact • Matching S. marinum isolates from infants and iguanas and environmental cultures • Iguana was in same tub that baby bathed in • Aquarium and other objects washed in sink where baby bottles washed.
Prevention of Reptile Transmission • Pet store owners, veterinarians, and pediatricians should alert owners • Wash hands thoroughly with soap and water after handling reptiles or reptile cages. • Persons at increased risk, e.g., children aged less than 5 years and immunocompromised persons should avoid contact with reptiles and should not have them in same house.
Prevention of Reptiles Transmission • Pet reptiles should not be kept in child care centers • Pet reptiles should not be allowed to roam freely throughout the home or living area. • Pet reptiles should be kept out of food-preparation areas.
Conditions Cryptosporidiosis Giardiasis Toxoplasmosis Larva migrans Trichinosis Prevention Good hygiene Good hygiene Good hygiene Good hygiene Treat animals Cook pork FECAL-ORAL - Parasites Other Issues water, day care water, day care undercooked meat raccoon roundworm wildlife
Protozoans – Cryptosporidia, Giardia • Most common transmission via water (Milwaukee) • Less sensitive to chlorine than bacteria, especially Cryptosporidia • Contamination from wild animals, livestock • Person to person - giardiasis in diapered day care • Animal to person – especially pound and kennel pups
Cryptosporidiosis and Giardiasis Prevention • Do not drink from streams, rivers or lakes • Surface water used for drinking should be filtered • Wash hands after changing diapers, cleaning up after pets, handling livestock or wild animals • High level of suspicion in pound/kennel pups – treat accordingly
Toxoplasmosis (another protozoan) • Woman infected in early pregnancy – severe damage or death of fetus • Immunocompromised – primary or reactivated disease is serious and can result in death • Healthy individuals – asymptomatic or mild illness • Reservoir – cats that eat rodents, birds • Oocysts in cat feces only 10-20 days • Intermediate hosts may carry oocysts in muscle
Toxoplasmosis Prevention • Cook meat well • Clean litter box daily (takes 1-5 days for oocysts to be infective) • Feed cats prepared food and discourage hunting • Wear gloves while gardening • Wash hands well
Toxocara and Ancylostoma • Larva migrans – visceral, ocular, etc. • Roundworm egg ingestion • Hookworm egg ingestion or larval penetration of skin • In foreign host (human) animal round worm larvae do not mature in GI tract, instead travel through tissue and cause damage • Baylisascaris procyonis – raccoon roundworm • Affinity for brain – children, rabbits, rodents, birds
Larva Migrans Prevention • Worm puppies and kittens at 2, 4, 6 and 8 weeks of age • Educate owners about good hygiene • Prevent soil contamination – roundworm eggs can survive in soil for extended periods
Prevention Treat birds Wear mask/respirator Avoid areas Wear respirator Reduce dust Eliminate rodents Disinfect Ventilate area Sources Parrot-like birds Bat/bird guano (> 2 years old) Rodent urine/feces (fresh) INHALATION Transmission Disease Psittacosis (chlamydiosis) Histoplasmosis Hantavirus
Psittacosis Issues • Infected birds can be asymptomatic • Shed intermittently in feces and respiratory secretions • Inhaled from desiccated droppings/secretions, dust from feathers • Stress initiates shedding/ illness • Some strains more pathogenic for birds/humans • Requires 45 day treatment of bird
Histoplasmosis • Mold in soil and yeast in animals and humans • Technically not a zoonoses – not transferred from infected animals • Fungus occurs naturally in highly organic soil or collections of bird or bat droppings • Takes several years to become infective • Spores are inhaled when disturbed, e.g., cleaning out buildings with bird or bat roosts
Histoplasmosis, continued • Most adults have been exposed and are immune, especially in midwest • Five clinical forms from asymptomatic to chronic disseminated or pulmonary • Can reactivate when immune system depressed • Prevent by dampening area and wearing respirator - best to have professional clean up, e.g., asbestos
Hantavirus Pulmonary Syndrome • Many different hantaviruses found worldwide • Some pathogenic, HPS or other organs, especially kidneys • Rodent hosts – Genus/species specific • Transmission via aerolization of rodent excreta
New World Hantaviruses Maciel Necromys benefactus Hu39694 Unknown Host Lechiguanas Oligoryzomys flavescens Pergamino Akodon azarae New York Peromyscus leucopus Sin Nombre Peromyscus maniculatus Prospect Hill Microtus pennsylvanicus Muleshoe Sigmodon hispidus Bloodland Lake Microtus ochrogaster Isla Vista Microtus californicus Bayou Oryzomys palustris Black Creek Canal Sigmodon hispidus El Moro Canyon Reithrodontomys megalotis Rio Segundo Reithrodontomys mexicanus Caño Delgadito Sigmodon alstoni Laguna Negra Calomys laucha Juquitiba Unknown Host Rio Mamore Oligoryzomys microtis Orán Oligoryzomys longicaudatus Bermejo Oligoryzomys chacoensis Andes Oligoryzomys longicaudatus
CDC DVRD DIVISION OF VIRAL AND RICKETTSIAL DISEASES
Cotton rat Deer mouse
Prevention – Rodent Control • Eliminate food sources and nesting sites • Prevent mice from entering dwellings • Encourage natural predators
Prevention - personal • Air buildings before cleaning • Dampen area with Clorox and water solution • Wear gloves to clean up and dispose • Avoid sleeping in areas inhabited by mice • Buildings • Burrows and nests at campsites
Disease Leptospirosis Tularemia Brucellosis Main Source Urine Blood, tissue Afterbirth (cattle, dogs) Prevention Wear gloves Protect wounds Vaccinate animals Wear gloves Protect wounds Wear gloves Vaccinate animals Other sources contaminated water ticks raw milk DIIRECT CONTACT Transmission
Disease Arboviral encephalitis Rocky Mountain spotted fever Lyme disease Ehrlichiosis Vector Mosquitoes Dog tick Deer tick Lone star Deer tick Prevention repellents protective clothing repellents protective clothing remove ticks “ “ VECTOR BORNE Transmission Reservoir Birds Ticks White footed mice Deer (?)
Mosquito Borne Encephalitis • Group of acute inflammatory viral diseases of short duration involving parts of the brain, spinal cord and meninges. • Signs and symptoms similar, but vary in rate and progress. • Most infections asymptomatic. • Usually fever, headache and if severe, stiff neck, stupor, confusion, coma.
Arboviral Encephalitis • Each disease caused by a specific virus (EEE, SLE, LaCrosse, West Nile) • Virus usually maintained in animal reservoir. • Transmitted by vector = infected mosquito. • Species varies with disease and geography • Amplification and bridge vectors
Human Arboviral Disease in Virginia • Eastern Equine Encephalitis • Tidewater - 1975 (2), 1998 (1); Henrico -1990 (1) • St. Louis Encephalitis • Richmond area - 1976 (4) • La Crosse Encephalitis • southwest Virginia - several cases yearly since 1994
West Nile Virus Transmission Cycle Mosquito vector Incidental infections West Nile virus West Nile virus Incidental infections Bird reservoir hosts
WNV hospitalized 62 persons in 1999 and seven of these died. WNV was detected in 194 birds and 25 horses (8 horses died).
US WNV - 2000 • From New Hampshire to North Carolina, concentrated around New York City • 21 humans, 2 deaths • 4,323 birds (87% crows) • 59 horses • Over 500 mosquito pools
21 14 15 5 1 1 2 9 1 3 WNV Activity Detected in Virginia in 2000 In 2000, over 600 dead birds were tested for WNV. Starting in early October, seven birds were found to be WNV positive. All were crows and were found in the following jurisdictions. Alexandria Fairfax Co. Spotsylvania Co. Hanover Co. Powhatan Co. Pr. Edward Co. Hampton
US WNV - 2001 • 5,190 birds • 100 horses • 38 humans • 511 mosquito pools
VA WNV -2001 • 195 birds • 4 horses • 1 mosquito pool
29 1 3 49 51 10 1 1 1 1 2 1 1 1 1 1 3 4 16 5 Testing Virginia Birds for WNV in 2001 As of mid October, a total of 1108 dead birds had been tested for WNV in Virginia. All but 39 of the 120 local health departments had had at least one bird tested. 180 birds have tested positive for WNV.
Preventing Arbovirus Infection • Personal protection • Clothing • Repellents (20 – 30% DEET, < 10% on children) • Reduce vectors • Eliminate standing water • Larvicides • Adulticides
Tick Borne Diseases • Lyme disease • Rocky Mountain spotted fever • Human monocytic ehrlichiosis • Human granulocytic ehrlichiosis
Lyme Disease Clinical Symptoms • Erythema migrans • 3 to 32 days after tick exposure • Malaise, headache, fever, stiff neck • Muscle aches and joint pain • Swollen lymph nodes • Chronic arthritis, heart and nervous system complications if not treated early
Lyme disease continued • Transmission • usually nymph stage when tick is actively feeding • adult tick can transmit disease • tick must be attached for > 24 hours • Tick life cycle • 2 years from egg to adult
Adult female Adult male Nymph Larvae
White Footed Mouse Borrelia burgdorferi