S1B4 - RNA viruses Flashcards
What are the three most common causes of aseptic meningitis?
The three most common causes of aseptic meningitis include
- Coxsackievirus
- Echovirus
- Mumps
What is the function of neuraminidase in the context of influenza?
Neuraminidase (NA) envelope protein cleaves HA-sialic acid interaction during budding to permit viral spread.
Describe the progression and appearance of the rash in measles.
The exanthem of measles infection is a maculopapular, blanching rash that appears a few days after the prodrome phase, and begins on the face and spreads centrifugally to involve the body and extremities.
What can be given as prophylaxis for immunocompromised patients at risk for severe RSV infection?
Palivizumab (blocks fusion protein F) can be used for prophylaxis in immunocompromised patents at risk for severe RSV infection.
Replication and transcription of rabies virus occurs in Negri bodies, which are pathognomonic of rabies infection. Negri bodies are cellular inclusion bodies which are…
- eosinophilic or basophilic?
- intranuclear or intracytoplasmic?
- found in neuron cell bodies in the spinal cord and CNS — especially in which 2 specific locations?
Replication and transcription of rabies virus occurs in eosinophilic cytoplasmic inclusions called Negri bodies within neuron cell bodies in the spinal cord and CNS (especially Purkinje cells in the cerebellum and pyramidal cells of the hippocampus).
Describe the basic virology of hantavirus (capsid symmetry, enveloped/nonenveloped, segmented/unsegmented, and genetic material). To which virus family does Hantavirus belong?
Hantavirus (Sin Nombre) is an enveloped, helical capsid virus with a negative-sense/ambisense, segmented single-stranded RNA (ssRNA) bunyavirus.
What are the presenting symptoms in a patient with hepatitis A?
Patients initially present with a prodromal stage (i.e. fever and flu-like symptoms), often progressing to the icteric stage (i.e. bilirubinuria, pale stools, and jaundice).
What are Cowdry Type A bodies composed of? What group of viruses is this specific to?
Cowdry Type A bodies are eosinophilic nuclear inclusions composed of nucleic acid and protein seen in cells infected with organisms within the herpesvirus family.
Describe the characteristics and classification of the virus causing Hepatitis A infection. How is it transmitted? Does it cause acute or chronic hepatitis?
HAV is a picornavirus that is transmitted fecal-oral and causes acute hepatitis (no chronic carrier state) that may be anicteric. HAV is commonly acquired by travelers.
What is the treatment for a mumps infection?
Treatment for mumps infection is supportive.
What disease does rotavirus cause?
Rotavirus is the most common cause of viral gastroenteritis in infant/young children (both fatal and non-fatal).
ROTA: “Right Out The Anus”
A 10-year-old boy who has an obsession with hamsters presents to the emergency department with an influenza-like symptoms, along with signs of meningismus. Hantavirus is ruled out of the differential diagnosis, but based on CSF results a viral etiology is suspected. What other causative virus could be responsible for this patient’s presentation?
Lymphocytic choriomeningitis virus (LCMV) is a rodent-borne arenavirus transmitted by exposure to the urine and feces of rodents, including mice and hamsters. Affected patients generally present with an influenza-like systemic illness accompanied by headache and meningismus.
Hepatitis E virus is endemic in what geographic areas?
HEV is endemic in Africa, Asia, and the Middle East.
What virus is responsible for SARS?
Severe acute respiratory syndrome (SARS) is caused by a certain strain of coronavirus.
Synthesis of what factor leads to the coagulation defects seen in Ebola virus infection?
Coagulation defects in Ebola virus infection occurs indirectly through the synthesis of tissue factor, which triggers the extrinsic coagulation pathway. In addition, the proinflammatory cytokines induce macrophage production of tissue factor.
What are some risk factors that may put you at risk for an Ebola virus infection?
Risk factors include recent travel to an African region where Ebola virus outbreaks have occurred, laboratory accident when working with Ebola, or illness in a healthcare worker during an epidemic in Africa.
In what virus family is Human T-cell lymphotropic virus?
What are some unique things about Human T-cell lymphotropic virus?
Human T-cell lymphotropic virus is in the retrovirus family.
- Able to immortalize or transform host cells; not cytolytic
- Transmission:
- HTLV-1 via milk and blood (found in Caribbean, Japan, South America, Africa);
- HTLV-2 via blood (geographic distribution is unclear.
- Presentations:
- asymptomatic infections (most common)
- Tropical spastic paraparesis (HTLV-1)
- Adult leukemia (acute T-cell lymphocytic leukemia, ALT) (HTLV-1) Non-hodgkin’s lymphoma
How is RSV transmitted?
Transmission of RSV occurs from respiratory droplets.
What is the mode of transmission for rotavirus?
Rotavirus has a fecal-oral transmission (common in preschools and day care centers).
Can you name 1 virus family which is nonenveloped with icosahedral capsid symmetry and contains dsRNA?
An example of a nonenveloped, icosahedral capsid, dsRNA virus is the reovirus family. Examples include rotavirus and Colorado tick fever virus.
How is measles diagnosed?
Diagnosis of measles is made via serology.
Most often by clinical presentation alone. Seroconversion, immuno-based or viral RNA tests are useful. Giant cells can be observed in tissue samples.
How does parainfluenza infection manifest in adults?
Parainfluenza infection in adults usually presents as a severe cold with nonspecific findings such as
- Fever
- Rhinorrhea
- Cough
- Sore throat
How is mumps virus transmitted?
Transmission of mumps virus occurs via respiratory droplets.
What is the pattern of rash progression seen in rubella?
The rash starts on the face and progresses down to extremities, just like with measles.



