Exam #4

Why is this virus an issue? Viral infection is responsible for ~500,000 deaths/year
*In the US ~30-40 deaths/year (primarily infants due to dehydration) What are the 3 stages of dehydration? 1. Mild= dry mucous membranes (THIRST)
2. Moderate= (mild+) and inability to cry tears and loss of skin turgor.
3. Severe= (mild+moderate) and rapid shallow breathing, cold extremities, rapid heart rate,lethargy-coma. What are the two main virus groups responsible for Viral Gastroenteritis? ROTAVIRUSES and NOROVIRUSES Characteristics of Rotaviruses:
(Gastroenteritis) Family= Reoviridae (in the same family with Reovirus)
Capsid= TRIPLE Icosahedral/naked
Genome= dsRNA/ 11 segments Epidemiology:
How are Rotaviruses characterized? By SEROGROUPS:

Serogroups (A,B,C,D,E,F,G); HUMANS infected by (A,B,C,G)
*MOST SEVERE= Serogroup A, serotypes 1,2,9 Rotavirus Immunity? Because of reassortment immunity is variable (not life long) Season of Rotaviruses? Year round, but more cases among children in the winter. *Transmission/**Incubation of Rotaviruses? *Fecal oral…Fomites
**2-3 days Symptoms of Rotaviruses? Low fever, Nausea, Vomiting, **DIARRHEA**
-Can last for up to a week
-normally good recovery Treatment/Prevention of Rotaviruses? Treatment: There are no specific drugs
Prevention:Rota Shield and Rotatec Rota Shield= -Live attenuated vaccine
-For types 1,2,3,4
Problems= Intusesception= Folding over of Bowel (resulted in death)

Rotatec= -Live attenuated
-For types 1,2,3,4,9
Given at: 2,4 and 6 months Characteristics of Noroviruses:
(Gastroenteritis) Family= Caliciviridae
Capsid= Icosahedral/naked
Genome= ssRNA+ When were Noroviruses first recognizes? Noroviruses were first recognized in 1968 in Norwalk Ohio. There was an outbreak, the causative agent (Norwalk agent) could not grow this agent.
EM= Norwalk Virus Season of Noroviruses? Occurs YEAR ROUND and world wide at any age (esp. in adults=OUTBREAKS..that usually occur on Cruise Ships) *Incubation/**symptoms of Noroviruses: *1-2 days
**Vomiting and Diarrhea Immunity of Noroviruses: Normally GOOD recovery, but some people can not even be infected,some have little to no immunity and others have longer immunity. Characteristics of ENTEROVIRUSES: **Responsible for gastrointestinal illness**
ALL enteroviruses are in Family= PICORNOVIRIDAE
-Genome= ssRNA+
**Diverse Group that includes polio virus) Different types of Enteroviruses: 1. Polio Virus (3)
2. Coxsackie A virus (24)
3. Coxsackie B virus (6)
4. Echoviruses (31) What does the prefix ECHO mean: Enteric Cytopathogenic Human Orphan Virus Transmission/Symptoms of Enteroviruses: Transmission= Fecal-Oral (traditionally speaking)
Symptoms= Nausea, Vomiting, Diarrhea

Incubation of Enteroviruses: Incubation= 2-3 days (virus remains local)
***Incubation could be 1-2 weeks, it can enter circulation =virus disseminates (esp. lymphatics…head to toe) Season of Enteroviruses= Year round, but esp. summer and early fall **Special Enterovirus syndromes**
1. Aseptic Menigitis= -Could be due to any of the enteroviruses
-Symptoms= Severe headache, Stiff neck, Fever, Nausea, Confusion,Seizures,Coma, Death
Season=Peak in Summer time
Transmission=Fecal-Oral/Respiratory **Special Enterovirus syndromes**
2. Pleurodynia= -Mostly due to COXSACKIE B
=Infection of the muscle (chest, neck and shoulders)
-Symptoms= Severe pain, High fever, Vomiting **Special Enterovirus syndromes**
3. Herpangina= -Mostly due to COXSACKIE A
=Large Oral Lesions (looks like a cold sore but deeper+bleeding)
-Symptoms= High fever, Severe sore throat, vomiting **Special Enterovirus syndromes**
4. Hand, Foot, Mouth Disease= -Mostly due to COXSACKIE A
=Rash on fingers, wrist, and ankles (due to capillary leakage)
-Symptoms= Low fever and small lesions in mouth **Special Enterovirus syndromes**
5. Conjunctivitis= -Mostly due to COXSACKIE A
=Life infection
-Symptoms= Bleeding in the eyes/ Hemorrhage and Severe life pain. **Special Enterovirus syndromes**
6. Cardiac Disease= -Mostly COXSACKIE B
= Infection of cardiac muscle
-Symptoms= May be years later…Immune attack on the heart tissue (Viral antigen)
-May manifest as a heart attack *Treatment/**Prevention of Enteroviruses: *No specific drugs..PICOVIR
**Only a vaccine for polio viruses
Both live and killed; given at 2,4,6 or 12-15 months and 4-6 years What is the Hepatitis? Infection and/or inflammation of the liver. What are the functions of the liver? -detoxifies chemicals
-Serum protein production (albumin/complement)
-Store Glycogen
**The liver recycles old RBC's
-Conjugates bilirubin and secretes their conjugates in BILE- Why is feces Brown? From the bilirubin in RBC's What happens if you interrupt the process of converting bilirubin to bile? JAUNDICE= yellowing of the skin, whites of eyes and dark urine.
(shows up after long periods of stress) Other symptoms of Hepatitis= Nausea, loss of appetite, vomiting, weakness, fatigue, fever What Hepatitis viruses are responsible/associated with liver infection? Hepatitis A,B,C
B=Greatest concern
-Hep. A official target for a vaccine, but Hep. B was the first to have a vaccine developed Characteristics of Hepatitis A virus?
**(In 2011/US) Family= Picornoviridae
** In 2011= 993 cases in US
TN= #17 Transmission of Hepatitis A virus: =fecal-oral
-Contaminated food and water
-contaminated shellfish (raw oysters)
-male homosexual contact *Season/**Incubation/***Symptoms of Hep. A: *There is no season!
**Incubation= 4 weeks (blood circulated but target=liver)
***Symptoms=Nausea, loss of appetite, vomiting, weakness, fatigue, fever Hep. A Immunity? -No chronic infection
-Associated with liver cancer
-Good Recovery/ Life long immunity Treatment of Hep. A virus: – No specific drugs
-PICOVIR can work against but was not approved…
Vaccines= Vaqta and Twinrix *Vaqta and **Twinrix *Vaqta is given in 2 doses (12-15 months and 6 month after)
**Twinrix is killed purified and is for both HAV and HAB
-given at birth, 2 months, 6 months Characteristics of Hepatitis B virus:
**(In 2011/US) -Family= Hepadnoviridae
-Capsid= Icosahedral with envelope
-Genome=Almost dsDNA
**In 2011= 2092 cases in US
-TN #2/FL#1 Transmission of Hepatitis B virus: -Blood/Body Fluids (*sexual Contact)
-Blood transfusion
-Saliva *Incubation/**Symptoms of Hepatitis B virus: *Incubation= 60-180 days (avg~120)
**Symptoms= Nausea, loss of appetite, vomiting, weakness, fatigue, fever
-May become chronic
~25% of adults
~90% of infants right after birth
—Is also associated with hepatocarcinoma— Treatment/Prevention of Hep. B virus: -There are no treatments
-Vaccine= TWINRIX
–Killed/purified/genetically engineered/prepared in saccharomyces cerevisae
-Given at bithh, 2 months,6 months
***Read chart in phone) What is the key to chronic infection? HBsAG remains and there are no Anti-HB's Characteristics of Hepatitis C virus:
*(In 2011/US) **The most common Hepatitis virus in population**
-Family= Flaviviridae
-Capsid= Icosahedral with envelope

*in 2011= 858 cases (TN#3/FL#1) Season and Transmission of Hepatitis C virus: -Season= NONE
-Transmission=sexual contact (more rare)
-#1 way to get infected= NEEDLES (illegal)
–IV drugs–Tatoos *Incubation/**Symptoms of Hep. C virus: *Incubation= 15-180 days (avg~ 45)
**Symptoms= Nausea, loss of appetite, vomiting, weakness, fatigue, fever BUT can be asymptomatic! Chronic Infection of Hep.C: Chronic infection occurs ~75% of the time!
-1-5% of chronic infection result in Hepatocarcinoma
–HCV is the #1 reason for liver transplants! Treatment/ Prevention of Hep.C virus: -Treatments= Interferon with RIBOVIRIN
-THERE ARE NOT YET ANY VACCINES FOR HCV Characteristics of Hepatitis D virus: ***Hep. D virus is a defective virus, it can not infect alone!!!***
Requires co-infection by HBV…is lacking the HBsAg= attachment
-Family= NOT SURE
-Capsid= Icosahedral/ Naked
-Genome= ssRNA- (has the greatest similarity to plant viruses) *Transmission/**Incubation/***Symptoms of Hep. D virus: EVERYTHING IS JUST LIKE HBV!!!!
*Transmission=Blood/Body Fluids (*sexual Contact)/Needles
**Incubation= 60-180 days (avg~120)
***Symptoms= Nausea, loss of appetite, vomiting, weakness, fatigue, fever Treatment/Prevention of Hep. D virus: Treatment= NONE
Prevention= HBV vaccine Characteristics of Hepatitis E Virus: -Family= Caliciviridae
-Farely rare in the US, mostly in Asia *Transmission/**Incubation/***Symptoms of Hep. E virus: *Transmission= Fecal-Oral
**Incubation= 14-65 days
***Symptoms= Nausea, loss of appetite, vomiting, weakness, fatigue, fever
-No chronic infection
-No association with cancer Characteristics of Hepatitis F virus: -Family= Togaviridae (like RUBELLA)
-IS NOT A HUMAN VIRUS…Known among Monkeys! How was Hepatitis F virus discovered? The virus was first recognized in the diarrhea of animal technicians
-There was slight jaundice
-Transmitted fecal-orally Characteristics of Hepatitis G virus: THIS IS A TRUE " ORPHAN " VIRUS!
-Family= Flavivirdae
-Cases are common in blood donor screening Transmission of Hepatitis G virus: Blood and Body Fluids Treatment/ Prevention of Hep. G virus: There are NO treatments or prevention for this virus…
-HGV infects hepatocytes and lymphocytes
-Blood should be screened for it and discarded if present! Characteristics of Human Immunodeficiency Viruses: -Family= Retroviridae
-Capsid= Complex with envelope
-Genome= ssRNA+/ 2 identical strands
-Lentiviruses= HIV (human), SIV (SImian), FIV (feline) What are the 2 types of HIV/ where are they prominent? There are 2 types:
-HIV-1= The vast majority of all infections
-HIV-2= esp. in Western Africa…166 cases in the US How is HIV characterized: -HIV-1= 2 groups…M and O
(within each group are clades)
-HIV-1,M: A,B,C,D,*E,F,G,H.*I,J,K
-HIV-1,O: A,B,C,D

-HIV-2: A,B,C,D,E,F

**HIV-1 and HIV-2 are 2 distinct viruses…they only share ~45%sequence homology What are the origin of HIV-1/2 ? -HIV-1 originated from a Chimpanze
-HIV-2 originated from Sooty Mongaby The timeline of HIV: -The first human death associated with AIDS=1959
-HIV appeared in humans in 1930-1931
(Lymphadenopathy among gay men…*Pneumonia turned into Pneumoncytis)
-The virus was isolated in 1983 by BARRE SINOUSI- in France The timeline of HIV cont'd: -In 1983 the virus was named HTLV-3
(Human T-cell leukemia virus type 3)
-The syndrome was name AIDS
-In 1986-HTLV-3 was renamed HIV-1
(and at the end of 1986 HIV-2 was found) Epidemiology of HIV: -In US ~1.2 million infected/~50,000 new cases/year
-CDC estimates about 20% of HIV+ individuals don't know it Incubation of HIV: -On average it takes anywhere between about 10-14 years to progress from HIV to AIDS
-It is estimated that 80% of HIV+ will go from HIV to AIDS in 15 years
HIV IS THE #1 CAUSE OF DEATH IN THE US…due to infection of Pneumoncytis Jiroveci How is AIDS Defined? AIDS= defined as less than 200 t-helper cells per mL of blood
-Most infections are asymptomatic but if there are symptoms they are non-specific and do resolve Treatment and Prevention of HIV: There are lots of Treatments (drugs)…
-Anti-reverse transcriptase
-Protease inhibitors
-Anti Integrase
**As far as vaccines…
Azidothymidine… Not yet approved…To date ~40 vaccines have f=gone to phase 1 trial, 21 to phase 3 and 3 to phase What families are include Arboviruses? Families Include:
-Flaviviridae What are the origin of Arboviruses? Arboviruses= Arthropod-Bore Viruses
#1=Mosquitos ~60%
#2=Tics ~20%
-Often blood feeding arthropods, fleas, biting black flies, fleas, lice etc. Epidemiology of Arboviruses: -There are 504 recognized arboviruses and 124 of those infect humans
-Season= NONE Transmission of Arboviruses: The normal cycle is from mosquito to bird.
-Humans are "Dead End" hosts…
(Mosquito takes blood meal from infected bird, virus replicates in mosquitos gut, it migrates to salivary glands, mosquito takes next blood meal and infects that host!) Why are humans considered a "Dead End"? Humans are considered a dead end because virus is not at a high enough titer. What are the outcome of infection with an arbovirus? -Vast majority= ASYMPTOMATIC-
1. Acute, Benign Fever (flu like fever)
2. Neuroinvassive (flu like fever and meningitis symptoms)
3. Hemorrhagic fever
-Immune mediated…Dengue= Infection with 1 type followed by infection by another type… What syndromes are associated with Arboviruses? 1. Western Equine Encephalitis= 7% mortality
2. Eastern Equine Encephalitis= MOST SERIOUS!
~30% mortality
3. California Encephalitis=(aka "serogropp or LaCrosse Encephalitis) ~1% mortality
4. St.Louis Encephalitis= ~3% mortality What syndromes are associated with Arboviruses? cont'd 5. West Nile Virus= still becoming established (~5% mortality)
-Unusual transmission …Human to Human…HOW?… Infected blood!
6. Dengue= Is becoming established Treatment/Prevention of Arboviruses: There are no treatments or vaccine for these viruses!
-It is best to prevent mosquito populations Characteristics of Rabies Virus: -Family= Rhabdoviridae
-Capsid= Helical with envelope
-Genome= ssRNA- Epidemiology of Rabies virus: ***Deadliest of all the viruses ..if untreated there is 100% mortality!
-Average of 1-2 cases/year…since 1980 there was 71 human cases…In 2011= 4-5 cases/year.
*ANY MAMMAL CAN SERVE AS HOSTS* Reservoir Hosts (in US): -North= Raccoons
-Southeast = Skunks
-Southwest= Wild dogs *Season/**Transmission/***Incubation of Rabies: *Season= NONE
**Transmission= BITE or scratch, where virus containing saliva gets into wound.
***Incubation= 1-3 months Symptoms of Rabies: Symptoms= Fever, Loss of appetite, Lethargy, Behavioral Changes (withdrawn/then irritated/then aggressive), Intense headache,*Hyper salivation and inabilty to swallow*, definite neurological problems…then COMA! Rabies Virus Replication: – Virus replicates in muscle, enters peripheral nerves, slow passive ascent toward spinal ganglia, central nervous system, replication again, rapid ascent to the brain, more replication, virus descends to eyes and salivary glands. Best place to be infected by Rabies virus: -Best place= LEG
-Worst place= FACE
*Because of the time factor Treatment/ Prevention of Rabies Virus: FIRST: Instill SIG at the bite site!

-at a site distinctly away from bite site
-killed/purified vaccine= 3 shots over 7 days What is an Oncovirus? Virus associated with cancer (cell transformation)=
-Loss of normal cell regulation
-Loss of genetic regulation
—translocation What are the 4 families associated with cancer? Families include:
1. Retroviridae
2. Herpesviridae
3. Papoaviridae
4. Hepandnoviridae

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