Wildlife Zoonoses and Synurbanization

Flashcards testing knowledge of wildlife zoonoses, synurbanization ecology, and zoonotic pathogen epidemiology based on veterinary public health lecture material.

What is the definition of synurbanization according to the lecture?

Synurbanization denotes the adjustment of wild animal populations to specific conditions of an urban environment in response to worldwide urbanization.

Which European bird and mammal species are cited as prominent examples of synurbanization?

Blackbird (Turdus merula), magpie (Pica pica), Hooded crow (Corvus corone cornix), kestrel (Falco tinnunculus), red squirrel (Sciurus vulgaris), Striped field mouse (Apodemus agrarius), rabbit (Oryctolagus cuniculus), and red fox (Vulpes vulpes).

What typical population and behavioral changes characterize wildlife undergoing synurbanization?

Higher population density with reduction of individual/pair/family territories; reduced migratory behavior; prolonged breeding seasons (including winter broods); altered circadian activity; increased longevity despite worse health parameters; changes in diet and foraging behavior; increased intraspecies aggression; and tameness toward humans.

To which viral family do hantaviruses belong, and what are their structural and genetic features?

They belong to the family Bunyaviridae and are enveloped, negative-sense single-stranded RNA viruses, with approximately $41$ identified viruses.

How do humans contract hantavirus infections from rodent reservoirs?

Through direct contact with the feces, saliva, or urine of infected rodents, or by inhalation of aerosolized virus from rodent excreta.

Which North American rodent species are recognized vectors of hantaviruses that cause Hantavirus Pulmonary Syndrome (HPS)?

The deer mouse, white-footed mouse, rice rat, and cotton rat. (Rodents such as hamsters, gerbils, house mice, roof rats, and Norway rats are not known to transmit HPS).

What are the hallmark physiological presentations and fatality rates of HFRS versus HPS?

Hemorrhagic fever with renal syndrome (HFRS) features impaired renal function with oliguria and has a case fatality rate up to $15\%$. Hantavirus pulmonary syndrome (HPS) causes respiratory failure from acute non-cardiogenic pulmonary edema and has a case fatality rate up to $50\%$.

What pathological syndrome occurs when hosts other than raccoons ingest eggs of Baylisascaris procyonis?

Larval migrans, where migrating larvae invade tissues including the brain and eye, causing eosinophilic encephalitis/meningoencephalitis, ocular disease, and eosinophilic cardiac pseudotumors.

How many eggs can a single female Baylisascaris procyonis produce daily, and how many can an infected raccoon shed each day?

A single adult female worm produces an estimated $115{,}000$ to $877{,}000$ eggs per day, and an infected raccoon can shed up to $45{,}000{,}000$ eggs daily.

Why can Hymenolepis nana tapeworm infections persist in a human host for years despite adults living only $4$ to $6$ weeks?

Internal autoinfection occurs when eggs remain in the intestine, hatch to release hexacanth embryos, and penetrate intestinal villi to continuously renew the infection cycle.

What common names are applied to Borna Disease Virus (BDV) in horses and cats, and what is its mortality rate in horses?

It is termed 'Sad Horse' Disease in horses (with an $80\%$ to $100\%$ mortality rate) and 'staggering disease' (spontaneous non-suppurative encephalomyelitis) in cats.

What blood-sucking insect vector shown here transmits Trypanosoma cruzi, the agent of Chagas disease?

Kissing bug (subfamily Triatominae).

What pathognomonic clinical sign of acute Chagas disease is depicted in this patient?

Romaña's sign (unilateral palpebral and periocular swelling).

Which medications are utilized for the treatment of Chagas disease (Trypanosoma cruzi)?

Benznidazole or nifurtimox.

Which tick genus shown here serves as both the vector and reservoir of Crimean-Congo Hemorrhagic Fever?

Hyalomma spp.

What is the human mortality rate of Crimean-Congo Hemorrhagic Fever (CCHF), and which animals serve as reservoirs?

CCHF has a $30\%$ human mortality rate; reservoirs include cattle, ostriches, and Hyalomma ticks.

Which virus family does Lymphocytic Choriomeningitis Virus (LCMV) belong to, and what is its primary reservoir host?

It belongs to the Arenaviridae family; the common house mouse is its primary reservoir (though hamsters can also serve as reservoirs).

Which two bacterial agents cause rat-bite fever, and how do their geographic prevalences differ?

Streptobacillus moniliformis causes rat-bite fever predominantly in the United States, whereas Spirillum minus causes it in Asia.

What is Haverhill fever and how is it contracted?

An epidemic form of Streptobacillus moniliformis infection acquired by ingesting contaminated unpasteurized milk.

How does the clinical course of rat-bite fever caused by Spirillum minus differ from the streptobacillary form?

The initial bite wound typically heals promptly, but inflammation recurs at the bite site after $4$ to $28$ days (usually $>10$ days), presenting with relapsing fever, regional lymphadenitis, and a roseolar-urticarial rash, whereas arthritis is rare.

Which retroviruses and filoviruses are documented zoonoses linked to bushmeat hunting, butchering, and consumption?

Simian Foamy Virus (SFV), human T-lymphotropic virus types $3$ and $4$ (HTLV-3 and HTLV-4), and Ebola virus (particularly through handling dead chimpanzees).

What pathogen caused an outbreak of $65$ human cases at a Colorado petting zoo, and what was the source of transmission?

Salmonella (salmonellosis), transmitted via direct contact with a wooden barrier around the Komodo dragon exhibit.

Which animal is the only known nonhuman natural host of Mycobacterium leprae?

The armadillo.

What clinical feature reliably differentiates monkeypox (mpox) infection from smallpox?

Monkeypox produces prominent swelling of lymph nodes (lymphadenopathy), which does not occur with smallpox.

What animal species represents the true reservoir of cowpox virus, and which domestic animal is now its primary transmitter to humans?

Wild rodents are the true reservoir hosts; domestic cats are currently the most common source of transmission to humans.

What is the clinical presentation and outcome of Macacine herpesvirus 1 (B-virus) in macaque monkeys versus untreated humans?

In macaques (Macaca spp.), infection is subclinical or limited to mild oral vesicles/conjunctivitis; in untreated humans, it causes fatal encephalitis and encephalomyelitis in $70\%$ of cases.

What is the demonstrated clinical outcome in humans occupationally infected with Simian Foamy Virus (SFV)?

Although SFV produces persistent retroviral infection in $1\%$ to $4\%$ of occupationally exposed persons, none of the infected individuals followed over $2$ to $20$ years have developed clinical illness.

What animal serves as the natural reservoir of Marburg virus, and what is the disease case-fatality rate?

The African fruit bat (Rousettus aegyptiacus), with human case-fatality rates ranging from $23\%$ to $90\%$.

Which of the five identified Ebola virus subtypes causes disease exclusively in nonhuman primates and not in humans?

Reston ebolavirus (the other four—Zaire, Sudan, Taï Forest, and Bundibugyo—cause disease in humans).

For how long can infectious Ebola virus persist in the semen of convalescent male survivors?

Up to $90$ days.

What initial fever criterion defines SARS, and which wildlife species were identified as plausible animal hosts?

A fever exceeding $100.4^\circ\text{F}$ ($>38.0^\circ\text{C}$), with civets and raccoon dogs identified as possible reservoir hosts.

What is the primary animal reservoir for Middle East Respiratory Syndrome Coronavirus (MERS-CoV), and what is its fatality rate?

Camels are the primary reservoir, and MERS-CoV is fatal in approximately $3$ or $4$ out of every $10$ reported patients ($30\%$ to $40\%$).

How many agent risk groups are established under the World Health Organization (WHO) laboratory biosecurity classification system?

$4$ general risk groups based on principal pathogen characteristics, disease severity, and natural modes of transmission.