(1) Arthropod Virus Flashcards
(126 cards)
1
Q
Arboviruses are also called what?
A
Arthropod-Borne Virus
Carried by infected vector
2
Q
maintained in nature through biological transmission between susceptible vertebrate hosts by BLOODFEEDING ARTHROPODS
A
Arboviruses
3
Q
how is the vertebrate infection occurs?
A
infected arthropod take a BLOOD MEAL - host is bitten passing the virus from the arthropod
4
Q
What are the three famillies under the Arboviruses?
A
- Togaviridae
- Bunyaviridae
- Flaviviridae
5
Q
Disease Mechanism of Toga Viruses and
Flavivirus
Viruses are Cytolytic, except
A
Rubella
Cytolytic = cell lysis
6
Q
Disease Mechanism of Toga Viruses and
Flavivirus
what does the virus establish?
A
systemic infection and viremia
7
Q
Disease Mechanism of Toga Viruses and
Flavivirus
Viruses are good inducers of?
A
interferon
(accounts for the flu-like symptoms)
8
Q
Disease Mechanism of Toga Viruses and Flavivirus
Flavivirus
what are the exception form the families that arent arboviruses
A
RUBELLA AND HEPATITIS C
9
Q
Disease Mechanism of Toga Viruses and Flavivirus
infect cells of the MONOCYTEMACROPHAGE LINEAGE.
A
Flaviviruses
Escape phagocytic process of the lineage
10
Q
Disease Mechanism of Toga Viruses and Flavivirus
enhance flavivirus
infection via Fc receptors on the macrophage
A
Nonneutralizing antibody
11
Q
if u see this card
A
study the table for symptoms
12
Q
In the Man-Arthropod-Man cycle
what is the cycle
A
- Arthropod (may or may not be infected)
- Arthropod had a blood meal on the human (may or may not be infected)
- The human that may or may not be infected can pass it to the arthropod - vice versa (one of them is infected as the principle)
- Arthropod can now transmit it to other susceptible human
13
Q
In the Animal-Arthropod-Man cycle
what is the cycle
A
- Infected animal gets bitten by the arthropod
- Arthropod can infect other animal
- Infected arthropod can infect the human after a blood meal
same w/ Man-Arthropod-Man cycle excpt infected animal as main source
14
Q
Enumerate the arhtropod vectors
A
- Mosquitoes
- Ticks
- Sandflies
15
Q
under the mosquitoes for arhtropod vectors, what infection can be acquired?
A
● Japanese encephalitis
● dengue
● yellow fever
● St. Louis encephalitis
● EEE, WEE, VEE etc.
16
Q
under the Ticks for arhtropod vectors, what infection can be acquired?
A
● Crimean-Congo hemorrhagic fever
● Various tickborne encephalitis’s etc.
17
Q
under the Sandflies for arhtropod vectors, what infection can be acquired?
A
● Sicilian Sandfly Fever
● Rift Valley fever
18
Q
TOF
In many cases, the actual reservoir is not known
A
True
19
Q
What are the animal reservoirs
A
- Birds
- Pigs
- Monkeys
- Rodents
20
Q
Birds are animal reservoir for what infections
A
- Japanese encephalitis
- St Louisencephalitis
- Eastern Equine Encephalitis (EEE)
- Western Equine Encephalitis
(WEE)
21
Q
Pigs are animal reservoir for what infections
A
Japanese encephalitis
22
Q
Monkeys are animal reservoir for what infections
A
Yellow Fever
23
Q
Rodents are animal reservoir for what infections
A
- Venezuelan Equine Encephalitis (VEE)
- Russian Spring-Summer encephalitis
24
Q
Major Arboviral Diseases
A
- YELLOW FEVER
- DENGUE
- JAPANESE B ENCEPHALITIS
- St Louis Encephalitis
- Russian spring summer encephalitis.
- Eastren Equine Encephalitis
- West Nile Fever
- Sand fly Fever
25
Major Arboviurses that cause ENCEPHALITIS
- Flaviviridae
- Togaviridae
- Bunyaviridae
26
# Major Arboviurses that cause ENCEPHALITIS
Flaviviridae, enumerate the encephalitis
● Japanese Encephalitis
● St. Louis Encephalitis
● West Nile
27
# Major Arboviurses that cause ENCEPHALITIS
Togaviridae, enumerate the encephalitis
● Eastern Equine Encephalitis
● Western Equine Encephalitis
28
# Major Arboviurses that cause ENCEPHALITIS
Bunyaviridae, enumerate the encephalitis
● La Crosse Encephalitis
29
what host can be the carrier, reservoir or source of virus?
Verterbrate Hosts
## Footnote
It will pass through a vector, then it can
transmit it to other animals or to Human
30
The name Togaviridae derived from?
**"Toga"**
meaning roman mantle or cloak referring to the viral
surface
31
enumerate the structural characterisitc of togaviridae
→ Spherical 50 — 70 nm
→ Bears the Nucleocapsid, 42 capsomeres
→ Positive sense single stranded RNA
32
Enumerate the infections under togaviridae
- Chikigunya Virus Infection
- Eastern Equine Encephalitis
- Western Equine Encephalitis
33
# Togaviridae: Identify what infection
→ 1952 Epidemic in Tanzania
→ Manifest as Bend Up with Severe Joint pains.
Chikigunya Virus Infection
34
Chikigunya Virus Infection
transmission
wild primates → Mosquito → Man
| → Carrier: MOSQUITO (accding to maam)
35
Chikigunya Virus Infection:
Clinical Manifestation
* Crippling Joint Pains
* Conjunctiivitis
* Lymphadenopathy
* Hemorrhagic Tendecies
36
Chikigunya Virus Infection:
DIagnosis
- Isolation of Viruses
- Serology → IgM
○ Preferred Method
- Neutralization and Hemagglutination inhibition tests
37
Chikigunya Virus Infection:
Control and Prevention
- Mosquito Control
○ Since mosquito is the main vector
- No vaccines
38
Chikigunya Virus Infection:
Othjer Diseases like Chikugunya
* Onyonng Nyong Viruses
* Simlike Forest Viruses
39
# Togaviridae: Identify what infection
Caused by a virus transmitted to humans and **horses** by the bite of an infected mosquito.
Eastern Equine Encephalitis
40
# Eastern Equine Encephalitis
TOF
Average of 4m cases per year States with largest number of cases: Florida, Georgia, Massachusetts,
and New Jersey
F
4 lang, does not affect human persistently
41
# Eastern Equine Encephalitis
Human cases occur **relatively infrequently**, largely because the primary transmission cycle
takes place in?
swamp areas
populations ntend to be limited
| Because the main infected population here is the horses
42
# Togaviridae: Identify what infection
→ Carrier: Mosquito-borne
→ Important cause of encephalitis in horses and humans in North America, mainly in the Western parts of the US and Canada
Western Equine Encephalitis
43
# Flavivirus
The name is derived from 'flavus' the Latin word meaning?
"yellow"
## Footnote
Refers to YELLOW FEVER VIRUS (first
infection associated with flaviviridae)
44
Enumerate the structure characterisitc of the FLAVIVIRIDAE
* Enveloped
* Single stranded RNA virus
* Morphology is not well defined
45
Enumerate the infection acquired under flaviviridea
- Japanese Encephalitis
- Yellow Fever
- Dengue Fever
- St. Louis Encephalitis
- West Nile Virus
46
# Flaviviridae: Identify what infection
First discovered and originally restricted to Japan. Now large scale epidemics occur in China, India and Other parts of Asia
Japanese Encephalitis
47
what is the arhtropod concerned with Japanese Encephalitis
Flavivirus, Transmitted by **CULEX MOSQUITOES (Culex tritaeniorchynchus)**
48
TOF
Japanese encphalitis are maintained in nature in a transmission cycle involving mosquitoes, birds and
horse
F
Mosquitoes, birds and PIG
49
human infection under japanesse encephalitis are?
SUBCLINICAL
No obvious signs and symptoms are
observe
50
in clinical cases for japanese encephalitis what are observed?
LIFE THREATENING
ENCEPHALITIS
51
diagnosis and prevention available for japanese encephalitis?
- Usually Diagnosed by Serology -- ELISA
- Nonspecific theraphy is available
52
Isolation of virus from japanese encephalitis are from???
from this isolation of virus, this can also detect the arbovirus specific rna, what site
| same answer for both
Blood, CSF, or
tissues
## Footnote
However very few reference laboratories can perform the isolation in view of the biosafety considerations
53
Transmission for japanese encephalitis
- Vector-borne disease
- Enzootic Cycle
54
Transmission for japanese encephalitis:
Reservoir and Amplifyin Hosts
* Pig
* Bats
* Aredie (wading) Birds
* Possibly reptiles and amphibians
55
Transmission for japanese encephalitis:
Incidental Hosts
- Horses
- Humans
- Others (lol napaka specific naman ni maam)
56
Prevention For japanese encephalitis
Japanese Encephalitis B Vaccine
57
what is used besides the japanese encephalitis b vaccine for the virus can be mistaken as malaria
**prophylaxis** must be supplemented by techniques to avoid bein bitten by mosquitoes
58
# Flaviviridae: Identify what infection
→ Present in Africa, Central and South America
→ Absent in India
→ ALMOST synonymous with dengue, since they have the same vector
Yellow Fever
59
what is the transmission for Yellow fever
Mosquito (Ades aegypti)
transmitted to:
* Human SkinLymphatic's
* Lymph nodes
* circulation liver
* Spleen
* Kidney
* Bone marrow
* Lymph glands
60
Clinical manifestation of Yellow virus
→ Necrotic lesions in **liver , kidney**
→ Mid zone — **liver**
→ Fatty degeneration — **kidney**
→ Hemorrhages/Circulatory collapse
→ Iniury to **Cardiac muscle** and to **Myocardium**
61
what are the CPE produced under yellow fever
Councilman Bodies -- this is a lesion
62
Laboratory Diagnosis for Yellow fever
* Intracerebral Inoculation
* Mosquito Cell lines – not recommended but good for research purposes
* PCR
* Serology – ELISA
○ IgM Raise of Titers
63
# Flaviviridae: Identify what infection
→ One of the Most common infection, esp in the PH in rainy seasson
→ mosquito-borne **viral** infection. The infection causes flu-like illness, and occasionally develops into a severe form
→ About half of the world's population is now at risk
Dengue Fever
64
Dengue is found in?
tropical and sub-tropical climates worldwide, mostly in urban and semiurban areas
65
what dengue progression is the leading cause of serious illness and death among children in some Asian
and latin american countries (especially whern undetected)
Severe dengue
66
Epidemiology of dengue accding to WHO
Reported dengue cases:
- 1996-0.4 M,
- 2005 → 1.3 M
- 2010 → 2.2 M
- 2015 → 3.2 M
- 2013: approx. 3.2 M severe cases, 9000 deaths
- 2016:American Regions → 2.38M, Western
- Pacific → 375,000 (Phil. 176,411 ; Malaysia - 100,028)
67
Epidemiology of dengue accding to DOH
58,598 total cases January 1 to August 5, 2017
68
# Pathogenicity
Dengue Virus Genome are composed of 2 structural genes, what are thos
Structural and
Non-structural Genes
## Footnote
Nonstrucutaral genes produces the
products that can be detected by serological
techniques
69
Dengue 3 Structural proteins
- C
- prM
- E
70
Dengue 7 Non- Structural proteins
- NS1
- NS2a
- NS2b
- NS3
- NS4a
- NS4b
- NS5
71
Dengue short Non- coding regions
5’ and 3’ ends
72
Serotypes of Dengue Virus
- DENV-1
- DENV-2
- DENV-3
- DENV-4
73
Different dengue serotrypes exist because of the?
Mutation
74
# Serotypes of Dengue Virus
Group of viruses classified together based on the antigen on the surface of the virus
Serotpyes
75
# Serotypes of Dengue Virus
TOF
Major Difference for human lies in the subtle difference in the surface protein of the different dengue subtypes
True
76
# Dengue
TOF
infection induces LIFE-LONG
PROTECTION against the infecting
serotype, but it also give long time cross protective immunity against the other type
F
it gives only a short time cross
protective immunity against the other type
## Footnote
to be immune to all dengue
serotype, mag pa infect ka sa lahat
ng serotype T__T AHJSFHASHF
77
The first infection cause mostly minor isease, but secondary infections has been reported to cause severe diseases (DHF or DSS) in both children and adults. This phenomenon is called
ANTIBODY-DEPENDENT ENHANCEMENT
78
# identify what flavivirus infection
→ Most common mosquito infection in the us
→ transmitted human pathogen in the US
→ Leading cause of epidemic flaviviral encephalitis
St. Louis Encephalitis
79
# identify what flavivirus infection
→ MOSQUITOBORNE ZOONOTIC ARBOVIRUS belonging to the genus Flavivirus in the family Flaviviridae
→ This flavivirus is found in temperate and tropical regions Of the world
→ First identified in the West Nile sub-region in the East African nation of Uganda in 1937
West Nile Virus (WNV)
80
what are the 2 disease manifestation of west nile virus
- Asymptomatic
- Symptomatic
81
# Disease manifestation of west nile virus
Approximately 80 percent of West
Nile virus infections in humans are
subclinical, which cause no
symptoms
Asymptomatic
82
# Disease manifestation of west nile virus
- Termed as West Nile Fever
- WITHOUT NEUROLOGICAL DISEASE — the time from infection to the appearance of symptoms (incubation period) is typically between 2—15 days.
Symptomatic
83
# Disease manifestation of west nile virus
- Symptoms may include fever, headaches, fatigue, muscle pain of aches, malaise, nausea, anorexia vomiting myalgias and rash.
- **Less than 1%** of the cases are severe and result in neurological disease when the central nervous system is affected
Symptomatic
84
BUNYAVIRIDAE give what infection?
La Crosse Encephalitis
85
→ On average 75 cases per year reported to the CDC
→ Most cases occur in children under 16 years old
La Crosse Encephalitis
86
# La Crosse Encephalitis
TOF
zonotic pathogen that cycles between the daytime biting tree hole mosquito, and vertebrate amplifier hosts (chipmunk, tree squirrel) in
deciduois forest habitats
F
ZOONOTIC (kulang isang o)
87
what year was the la crosse encephalitis isolated?
1963 -- — isolated in La Crosse, WI from the brain of a child who died from encephalitis
88
enumerate the structure characteristic of ARENAVIRIDAE
→ ssRNA Virus
→ Enveloped Virus
→ 120 nm in diameter
→ Spherical to pleomorphic Shape
→ Contain 8-10nm long projection
89
what is the main cause of ARENAVIRUSES
Causes: ACUTE VIRAL HEMMORHAGIC FEVER
- Fever
- Shocks
- Increase Permeability of Blood Vessel
90
Transmission present for arenaviruses
- Rodent-Human
- Human-human
91
Identify what transmission for arenaviruses
- Contaminated Food
- Rodent Consumption
Rodent-Human
92
Identify what transmission for arenaviruses
- Direct Inoculation
- Contaminated Secretion
Human-Human
93
Enumerate the strcutural characteristic of RHABDOVIRIDAE
- Enveloped
- BULLET-SHAPED
- ssRNA virons
94
what does the rhabdoviruses infection cause?
slow, progressive zoonotic disease
95
primary reservoirs of rhabdoviruses
**wild mammals**
it can be spread by both wild and domestic mammals by bites, scratches, and inhalation Of droplets
96
Important virus under rhabdoviridae
- LYSSA VIRUS - RABIES VIRUS
○ Lyssa means Rage (Dr.T.V.Rao. MD)
97
subtypes for rhabdoviruses
- Fixed Virus
- Street Virus
98
# identify what subtype of rhabdoviruses
- One whose virulence and incubation period have been stabilized by serial passage and remained fixed during further transmission.
- Rabies virus at as undergone serial passage through rabbits, thus stabilizing its virulence and incubation period
Fixed Virus
99
# identify what subtype of rhabdoviruses
- Virus from a naturally infected animal, as opposed to a laboratory adapted strain of the virus
- The virulent rabies virus from a rabid domestic animal that has contracted the disease from a bite or scratch of another animal.
Street Virus
100
# rhabdoviruses
TOF
Any Mammal Can get Rabies
true
* Raccoons, skunks, foxes and bats
* Dogs, cats, cattle and ferrets
* Humans
| ONLY WARM BLOODED MAMMALS CAN GET INFECTED
## Footnote
diko gets si maam pero sinabi niya yam
101
# identify what rhabdovirus
→ Latin "Rabhas" Frenzy
→ Mad mammals biting Humans lead to Rabies.
Rabies
102
Symptoms of rabies
Hydrophobia Fear of Water, Saliva of Rabid dogs
103
what are the prevention available of rabies
Pasture's success – Vaccination
| NEED TO BE IMMEDIATELY GIVEN
104
what are the history behind Pasture's success – Vaccination
- Fixed virus from Rabbit injected into Joseph Meister
- Injected 13 injection of the cord vaccine.
105
Transmission of rabies
- Abrasions or scratches on skin.
- Mucous membrane exposed to saliva.
- Most frequently via deep penetrating bite wounds.
- Other Routes:
○ Inhalation -Bat infected caves.
○ Ingestion of dead /infected animal meat
○ Corneal transplantation
106
Pathogenesis of Rabies
Live Virus → Epidermids, Mucos Membrance
↓
Peripheral Nerve
↓ Centripetally
CNS (gray Matter)
↓ Centrifugally
Other tissue (salivary glands..etc)
107
# Pathogenesis of Rabies
Virus travels through
axoplasm
108
# Pathogenesis of Rabies
where does the axoplasm travels towards?
toward the
spinal cord at the rate of 3mm/hour, then Towards the brain
109
# Pathogenesis of Rabies
what happens after it travelled to brain (CNS)?
Spread from **brain
centrifugally** to various parts of the body
110
# Pathogenesis of Rabies
where does it multiplies?
salivary glands and shed in
the saliva, cornea, facial tissues skin
111
# Pathogenesis of Rabies
incubation period
1-3 Months
| May be average from 7days to 3 years
112
# Pathogenesis of Rabies
stage of disease
- Prodrome
- Acute Encephalitis
- Coma/Death
113
# Category as per WHO
touching or feeding
suspect animals, but skin is intact
CATEGORY 1
114
# Category as per WHO
minor scratches without
bleeding from contact, or licks on broken
skin
CATEGORY 2
115
# Category as per WHO
one or more bites, scratches, licks on broken skin, or other contact that breaks the skin; or exposure to bats
CATEGORY 3
116
Clinical Findings of rabies
○ Bizarre behavior.
○ Agitation
○ Seizures.
○ Difficulty in drinking.
○ Patients will be able to eat solids
○ Afraid of water - Hydrophobia.
○ Even sight of sound disturbs the
patient.
○ But suffer with intense thirst.
○ Spasms of Pharynx produces
choking
○ Death in 1 -6 days.
○ Respiratory arrest / Death / Some
may survive.
| familliarize nalang tih
117
Symptoms of rabies
* Headache, fever, sore throat
* Nervousness, confusion
* Pain or tingling at the site of the bite
* **HALLUCINATIONS** – Seeing things that are not really there
* **HYDROPHOBIA** – "Fear Of water" due to spasms in the throat
* **PARALYSIS** – Unable to move parts of the body (infected CNS)
118
# Diagnosis Of Rabies
human rabies is diagnosed
primarily on the basis of?
- clinical symptoms and signs
- and a corroborative history of or evidence of an animal bite, death of an animal,
- and incomplete or no vaccination following exposure
119
# Diagnosis Of Rabies
The facility for laboratory diagnosis and confirmation of rabies, be it in humans or in animals, is available
premortem in only a
few institutions
120
# Diagnosis Of Rabies: Techniques
Post mortem Diagnosis by
demonstration of
NEGRI BODIES
121
# Diagnosis Of Rabies: Techniques
Isolation of virus →
Mice brain inoculation
122
# Diagnosis Of Rabies: Techniques
Tissue culture on culture lines →
W 138, BHK
123
# Diagnosis Of Rabies: Techniques
an emerging method
PCR
124
# Diagnosis Of Rabies: Techniques
Immunoflourescent methods →
corneal impression method
125
# Rabies
describe the characteris of NEGRI BODIES
- Eosinophilic
- sharply outlined
- pathognomonic inclusion Bodies (2-10 gm in diameter) found in the Cytoplasm of certain nerve
126
Rabies prevention
- Vaccination
- Pre-exposure Prophylaxis
- Post-exposure prophylaxis
