Caliciviridae, Filoviridae, Togaviridae

Question 1

Structure: Small (___), rounded, nonenveloped, single- stranded, positive RNA viruses.
* Cause ___ in humans.
* Previously recognized as major animal pathogens with a broad host range.
* ____ classified in the family of this in the 1990s.
*___ include__ and __ genera.
* Genogroups: ___ anad ___

Answer 1

CALICIVIRIDAE
-30-38 nm
- acute gastroenteritis
- Noroviruses (formerly Norwalk-like viruses)
- Human caliciviruses (HuCVs)
- Norovirus and Sapovirus
- Norovirus (I, II, IV) and Sapovirus (I, II, IV, V)

Question 2

Approximately 685 million cases of gastroenteritis caused by __ annually.
* About 200 million cases occur in children under 5, leading to 50,000 to 70,000 deaths yearly, mostly in developing countries.
* Major public health concern in both low- and high-income countries.
* MOT: Rapid spread due to ___, low infectious
dose (____), and high environmental stability.
* Easily transmitted via food, water, person-to-person contact, and airborne droplets.
* Virus persists in water despite treatment processes

Answer 2

CALICIVIRIDAE
Norovirus
fecal-oral transmission
<100 virus particles

Question 3

Moderate to severe gastroenteritis: ___,___,___,__ anad ___
* Symptoms typically appear __ post-infection and last ___.
* Vomiting more common in children than adults.
* ____ causes mild to moderate gastroenteritis, more prevalent in infants and toddlers

Answer 3

CALICIVIRIDAE
nausea, abdominal cramps, vomiting, watery diarrhea
- 1-2 days
- 1-3 days
- Sapovirus

Question 4

• Maximum shedding occurs at symptom onset; can continue for 2- 3 weeks after symptoms resolve.
• Infection does not confer long-lasting immunity, complicating control of transmission

Answer 4

Viral Shedding

Question 5

Diagnosis of CALICIVIRIDAE
* Culture in __
* __ is the most widely used identification method.
* Commercial __ kits available but have lower sensitivity and specificity than RT-PCR.
* Multiplex NAATs (e.g., ___ and ___) can detect Noroviruses and Sapoviruses from __ samples.

Answer 5

Human Intestinal Enteroids (HEI)
-RT-PCR
- ELISA
- Verigene Enteric Pathogens Test, FilmArray gastrointestinal pane
- stool

Question 6

Enveloped, complex, pleomorphic rodlike shaped capsid, negative sense SSRNA
* __ and __ - classified as members of the
family ___ but are now classified as___
* Long threadlike viruses, hence the name (____) -
range in size from ____.
* Cause severe or fatal hemorrhagic fevers and are endemic in Africa

Answer 6

FILOVIRIDAE
- Marburg and Ebola viruses
- Rhabdoviridae
- Filoviruses (Filoviridae)
- filum means thread
- 80 to 800–1000 nm

Question 7

MOT: Direct contact with bodily fluids, infected animals (__,__ and ___), fomites, sexual transmission
* Incubation period: __
* Fever, severe headache, muscle pain, weakness, gastrointestinal symptoms, hemorrhagic symptoms (bleeding from the eyes, ears, nose, and mouth, as well as internal bleeding) ultimately leading to multi-organ failure and death

Answer 7

FILOVIRIDAE
- fruit bats, monkeys, apes
- 2-21 days

Question 8

• Named after the Ebola river
• 1979 Ebola re-emerged in __, with serial person-to-person spread
• Another epidemic occurred in ____, in __.

Answer 8

Ebola Virus
- Sudan
- Kikwit, Zaire 1995

Question 9

Ebola virus Strains

Answer 9

Zaire ebolavirus
Sudan ebolavirus
Tai Forest ebolavirus
Bundibugyo ebolavirus:
Reston ebolavirus

Question 10

The most lethal strain, responsible for the majority of
outbreaks, with a mortality rate ranging from 50% to 90%

Answer 10

Zaire ebolavirus:

Question 11

: Associated with outbreaks in Sudan and Uganda,
with a mortality rate of about 40% to 60%

Answer 11

Sudan ebolavirus

Question 12

: A rare strain with a lower mortality rate,
associated with a single case

Answer 12

Tai Forest ebolavirus

Question 13

: Identified in Uganda, with a mortality rate of
approximately 25% to 50%.

Answer 13

Bundibugyo ebolavirus

Question 14

: Primarily found in animals, particularly in the
Philippines, and is not known to cause disease in humans

Answer 14

Reston ebolavirus

Question 15

Ebola Virus Pathogenesis

Answer 15

Filovirus Replication
Cytokine Storm
Tissue Damage

Question 16

: immune cells such as monocytes,
macrophages, and dendritic cells

Answer 16

Filovirus Replication

Question 17

production of high levels of proinflammatory
cytokines, similar to what occurs with superantigens

Answer 17

Cytokine Storm:

Question 18

necrosis in the liver, spleen, lymph nodes, and
lungs

Answer 18

Tissue Damage:

Question 19

• The virus was first identified in ___ during simultaneous outbreaks in__,__,____,___ and ___
• linked to laboratory workers exposed to infected ____

Answer 19

Marburg Virus
- 1967
- Marburg and Frankfurt, Germany, and in Belgrade, Serbia
- African green monkeys

Question 20

Marburg Virus Strains

Answer 20

Marburg Virus (Marburg, Germany)
Ravn Virus

Question 21

: The original strain,
associated with the first outbreaks.

Answer 21

Marburg Virus (Marburg, Germany)

Question 22

: Identified in a 1987 outbreak in the Democratic
Republic of the Congo, it is closely related to the Marburg virus.

Answer 22

Ravn Virus

Question 23

Diagnosis of FILOVIRIDAE
* __ A primary method for identifying the viruses.
* __ Available in some research settings.
* __: Conducted in BSL-4 laboratories.
* ____: Used to detect IgM and IgG antibodies
against the Ebola virus.

Answer 23

RT-PCR Testing:
Electron Microscopy
Cell Culture
Antigen-Capture ELISA

Question 24

Treatment/Prevention of FILOVIRIDAE
* Supportive Care:__,___,__ ___

Answer 24

Fluid replacement therapy, kidney dialysis,
blood transfusions, favipiravir

Question 25

Treatment/Prevention of FILOVIRIDAE
Monoclonal Antibodies: ___ aand __

Answer 25

Treatments like ZMapp and MIL 77 are

Question 26

Utilizing blood or plasma from
recovered patients to provide immune support.

Answer 26

Convalescent Plasma Therapy:

Question 27

Vaccines of FILOVIRIDAE: At least 15 Ebola vaccines are in development, with____ emerging as the first to complete Phase III clinical
trials, showing substantial protection against EVD.

Answer 27

rVSV-ZEBOV

Question 28

Major genera : __,___ and ___
* ___is the only member of the rubivirus group; disease manifestation: __ and its means of
spread differ from those of the alphaviruses
* Spherical enveloped viruses with a diameter of ___
genome is single stranded RNA
* From ‘toga’, meaning the ___, and refers to the viral envelope

Answer 28

TOGAVIRIDAE
– Alphavirus, Rubivirus, and Arterivirus
- Rubella virus
-German measles
- 50–70 nm
- roman mantle or cloak

Question 29

__ genus consists of about 32 viruses of
which at least 13 are known to infect humans.
✓All of them are mosquito borne

Answer 29

Alphavirus

Question 30

___, which is not arthropod borne and
which causes rubella

Answer 30

Rubivirus

Question 31

• No known ___ cause disease in humans

Answer 31

Arteriviruses

Question 32

Alphavirus

Answer 32

A. Encephalitis viruses
1. Eastern equine encephalitis (EEE)
2. Western equine encephalitis (WEE)
3. Venezuelan equine encephalitis (VEE)
B. Viruses causing febrile illness
1. Chikungunya virus (CHIKV)
2. O’nyong-nyong virus (ONNV)
3. Semliki Forest virus
4. Sindbis virus
5. Ross river virus

Question 33

• Three members: __,__ and ___ cause encephalitis in horses and humans
• Vectors:__ and __
• Reservoir: ____
• Vaccine: ___ have been developed for EEE
  and WEE and a ___ for VEE

Answer 33

Alphavirus—Encephalitis viruses
- Eastern, Western and Venezuelan equine
encephalitis viruses
- Culex and Anopheles mosquitoes
- wild birds
- Formalinized vaccines
- live attenuated vaccine

Question 34

• In ___, means ‘that which bends up’, and refers
  to the posture assumed by patients suffering from severe joint pains
• Incubation period is __ with an average of ____
• Vector is ___.
• No animal reservoir has been identified

Answer 34

Chikungunya Virus
- Swahili
-1–12 days
- 2–3 days
- Aedes aegypti

Question 35

Confined to Africa, is closely related to the chikungunya virus antigenically and causes a similar disease.
* Transmitted by the anopheles species __ and ___
* ___causes a similar disease in the west India and South America

Answer 35

O’nyong-nyong Virus
- (Anopheles funestus and Anopheles gambiae)
- Mayaro virus

Question 36

• Has not been associated with clinical illness in humans though neutralizing
  antibodies to the virus have been demonstrated in Africans

Answer 36

Semliki Forest Virus

Question 37

• Originally’ isolated from __ in the Sindbis district of
  Egypt in 1952, has subsequently been recovered from other parts of Africa, India, Philippines and Australia.
• In Africa, it is known to be associated with febrile illness in human beings

Answer 37

Sindbis Virus
- culex mosquitoes

Question 38

• Has been associated with epidemic polyarthritis in Australia

Answer 38

Ross River Virus

Question 39

“____”
* highly contagious virus that primarily affects humans and is transmitted through respiratory droplets when an infected person coughs or sneezes.
* can also be transmitted from mother to fetus during pregnancy
* Incubation period: ___
* Common symptoms include Mild fever, rash that starts on the face and spreads to the rest of the body, ___ (swollen lymph nodes), joint pain (more common in adults), cold-like symptoms (e.g., runny nose, sore throat)

Answer 39

Rubivirus—Rubella Virus

“German Measles”
- 14-21 days
- lymphadenopathy

Question 40

Infection during the first trimester poses
significant risks to the developing fetus,
potentially leading to___
* CRS can result in serious birth defects,
including:
1
2
3
4
5
* The risk of it is highest when the
mother is infected during the first
trimester.

Answer 40

Rubivirus—Rubella Virus
- congenital rubella syndrome (CRS)
-* Heart defects (e.g., patent ductus
arteriosus)
* Hearing loss
* Cataracts
* Microcephaly
* Developmental delays

Question 41

• Diagnosis is primarily based on clinical presentation, including characteristic rash and associated symptoms
• Serological tests can detect specific IgM and IgG antibodies against rubella virus.
• ____can be used to detect viral RNA in clinical specimens.

Answer 41

Rubivirus—Rubella Virus
-PCR (polymerase chain reaction) tests

Question 42

Vaccination:
* The most effective way to prevent rubella and its complications is through vaccination.
* The ___ vaccine is commonly
administered in childhood, typically around __
with a booster dose given between ___

Answer 42

MMR (measles, mumps, rubella)
-12-15 months of age
- 4-6 years