Viruses - RNA (-) sense Flashcards

Question

**_Respiratory Syncytial Virus_ (RSV) (a **_Paramyxo_**virus)** signs and symptoms

Answer 1

**_Paranormal Mixer_** * **Attaches to _G protein_** to **infect respiratory** **epithelial** cells * **_Bronchiolitis_** and **_Pneumonia_** (**_most_ common cause** of these **in _infants_!!!**) * **Rhinitis** and **Pharyngitis**

Answer 2

**_Paranormal Mixer_** * **_Fusion_ proteins** (NO HA or NA for RSV) **Fusion proteins** on the surface of the virus **cause** the **cell membranes** on **nearby giant** multinucleated **cells** **to merge** and **stick** together, **forming _syncytia_**.

Answer 3

**_Paranormal Mixer_** * ****_Rib_**avirion** for **adults**.**\*** **\*** (**_Not_** _children_ or _pregnant_ women!!!) * **_Palivisumab_**, a **monoclonal antibody** (**Ig**_G_****) **against** the **_F protein_** of RSV, is used for **high risk children** and **premies**.

Answer 4

**_Paranormal Mixer_** **_Croup_!** * AKA **_seal bark_ cough**, ****_in_**spiratory strider**, or **_L_**aryngo**_t_**racheo**_b_**ronchitis. * characterized by a **"barking" cough**, **stridor**(harsh or grating sound), **hoarseness**, and **difficulty breathing** which usually **worsens at night**. * **_Steeple_** radiographic sign **on xray** due to **narrowing** of the **_subglottic_ region** from **swelling**.

Answer 5

**_Paranormal Mixer_** Mainly affects **children!!!** (Adults usually get a severe "cold") 1. **Hemagglutinin** (**_HA_**) 2. **Fusion** proteins 3. **Neuraminidase** (**_NA_**)

Answer 6

**_Rabid Wrecking Yard_** **_Bullet**_ shaped _**NEG**_ sense _****S**_S **_R_**NA** **_Enveloped_** virus **_Helical_** nucleocapsid (like Filo and Arena) **_Negri bodies_** (**eosinophilic** cytoplasmic **inclusions**) **found in** **_hippocampus_** (**pyramidal** cells) or **_cerebellum_** (soma of **perkinje** cells) on **biopsy** or **autopsy**.

Answer 7

**_Rabid Wrecking Yard_** **_Zoonotic_ virus** (**carried** by **animals** and **transmitted** to **humans**) In **U.S.** most common carrier is **_bats_** In **undeveloped countries _dogs_** also common carriers. **Squirrels**, **skunks**, **foxes**, and **raccoons** also carry.

Answer 8

**_Rabid Wrecking Yard_** * **_Glycoprotein_** on Rabies virus (**G-protein**) **binds** to **_Nicotinic ACh_ receptors** in the **_post_ synaptic membrane** in the **NMJ**. * **_Replicates_ in** the motor neurons **motor _end plates_**. * Rabies **moves _retrograde_** via peripheral nerves (1-3 mm per day) **to** the **_dorsal root_ ganglia** (can cause muscle spasms and tingling). * Spreads to **_brain_**.

Answer 9

**_Rabid Wrecking Yard_** * **Muscle spasms** and **tingling** * **_↑ salivary_ production** (once virus is in the salivary glands) & **excruciating _spasms_** of **muscles in throat** and **larynx** → **difficulty** in **swallowing** (**_dysphagia_**) → **_foaming_ of mouth** * **_Encephalopathy_** and **_high_ fever**

Answer 10

**_Rabid Wrecking Yard_** 1. **_Antidote_** w/ **_passive_** **preformed antibodies** (Human rabies **Ig**_G_****) **prior to symptoms** (can be weeks to months before symptoms appear) **_AND_****...** 2. **_Killed vaccine_****\*** for **_active_ immunity**. **\*** (**_Killed vaccine_** tx is given even if just wake up with a bat in the room) **\***

Answer 11

**_Soccer Field'o Virus_** **\*\*\*** **_Marburg_** and **_Ebola_** **\*\*\*** **_NEG**_ sense _****S**_S **_R_**NA** **_Enveloped_** virus **_Helical_** nucleocapsid (like Rabdo and Arena)

Answer 12

**_Soccer Field'o Virus_** * **_Marburg_** (usually **bat\*** **vector**) * **_Ebola_** (usually **monkey\* vector**) **In the U.S.** **_body fluids_** (especially **after death**) can **spread Filovirus**, so **_healthcare_ workers** are most **likely to get it**. **\*** Either bats or monkeys can be vectors for both, and bats "might" be the viral reservoir.

Answer 13

**_Soccer Field'o Virus_** **\*\*\* _Marburg_** and **_Ebola_** **\*\*\*** * **_Hemorrhagic fever_** (**sweating**, **fever**, **_petechial_ rash**) * End **organ failure** * Severe **blood loss** → **_Shock_** * **Death**

Answer 14

**_Paul Bunyavirus_** **_NEG**_ sense _****S**_S **_R_**NA** **_Enveloped_** virus (**obtained from **_gol_**gi _bodies_** of host cells!!!) **_3_ _Circular_ Segments** (**B.O.A.R.** mnemonic)

Answer 15

**_Paul Bunyavirus_** 1) **_Robovirus_:** transmitted through **rodents** (**_Deer mouse_** **urine** and **pellets**). (**Ro**bovirus like Arenavirus!) * **_Hantavirus_** 2) **_Arboviruses_:\*** transmitted through **_mosquito_ vector.** (Arbovirus like the togavirus!) * **_Rift Valley Fever_**, **_California Encephalitis_** (_aedes_ mosquito) **\* _All_ Bunyaviruses _except_** **Hanta**virus **are Arbo**viruses.

Answer 16

**_Paul Bunyavirus_** * Causes **_pulmonary_ edema** via **_capillary_ leak** and **prerenal _azotemia_** (excess of nitrogen compounds in blood stream due to lack of blood flow to each kidney) * **_Hemorrhagic fever_**

Answer 17

**_Paul Bunyavirus_** * Occurs mostly in **_children_** * **Myalgias** and **fever** * **Seizures** * **Encephalitis** (Usually not fatal, mostly causes neurological problems.)

Answer 18

**_Welcome to the Arenavirus_** * **_NEG**_ sense _****S**_S **_R_**NA** * **_AMISENSE_!!!** can also encode POS sense * **_Enveloped_** virus * **Segmented**, but **only _2_** reassortable **segments** (**B.O.A.R.** mnemonic) * **_Helical_** nucleocapsid (like Rabdo and Filo) * Characteristic **_granular sandy_** **_outer_ capsid** on EM

Answer 19

**_Welcome to the Arenavirus_** Transmitted by **_rodents_**. (**Ro**bovirus like Bunyavirus!) The **common house _mouse_** (**Mus musculus**) is the **primary host**, but **other rodents** such as **hamsters** can transmit LCMV **if** they were **infected by** a **mouse**.

Answer 20

**_Welcome to the Arenavirus_** ****_Bi_**phasic _febrile_ illness** 1) _**Initial phase**, which may **last** as long as a **week**_: * **_Fever_**, malaise, lack of appetite, muscle aches, **headache**, nausea, and vomiting 2) _**Following** a **few days of recovery**, a **2nd phase** may occur_: * **Aseptic** **_meningitis_**, **encephalitis**, or meningoencephalitis. * also can cause **acute hydrocephalus**

Answer 21

**_Welcome to the Arenavirus_** * **_Tx_** is **supportive care** for symptoms such as meningitis. **No chronic infection** has been described in humans, and after the acute phase of illness, the **virus is cleared from the body** * **_LCMV_** _can be_ **_inactivated_** By heating, low pH, irradiation, detergents etc.

Answer 22

**_A Race on the Rio_** * **_NEG**_ sense _****D**_S **_R_**NA** * **DS! DS! DS!** (**_Only_ **_R_**NA **_D_**S** in sketchy!) * **_NAKED_** virus * avg of **_11_** **Segments,** 9-12 (**B.O.A.R.** mnemonic)

Answer 23

**_A Race on the Rio_** * **Fecal-oral** transmission * **Toxin mediated** (NSP4 **_entero_**toxin) **_secretory_ diarrhea**. * **NSP4 ↑ _Cl_^- _permeability_** → **secretory** **diarrhea** that is **explosive** and **watery** (like norovirus, think **_Rota_**virus sounds like **_rota_**te propeller). * **Classic outbreaks** are in **_winter_!** * **_Children_** most at risk (**infants**, **daycare**, etc). * **#1 cause** of **severe diarrhea** in **young children!**

Answer 24

**_A Race on the Rio_** * **_Colorado_ _Tick_ Virus** * Symptoms include **myalgia**, **fever**, and **vomiting**. * **NO** _rash_ **!!!** * **ddx** from _Rocky Mountain Spotted Fever_ due to **_lack_ of** a **_rash_** with **Colorado Tick Virus**.

Answer 25

**_A Race on the Rio_** **Supportive care** and **oral rehydration**

Answer 26

**_A Race on the Rio_** * **_Live_ attenuated _oral_** vaccine * 1^st dose given before 3 months of age due to: 1. **_Decreased_** **efficacy** 2. May **_increase_ risk** of **_intussusception_****\*** **\*** (stimulation and enlargement of **peyers patches** → which then act as **lead points** for the **intestine** to **_telescope_ into _itself_** → can cut off blood supply → and possible bowel perforation.