10 - RNA Viruses

reoviridae

the only double stranded RNA virus

• picornaviridae

• caliciviridae

• reoviridae

the only naked rna virus

reverse transcriptase

converts single stranded RNA genome into double stranded DNA genome

reverse transcriptase

enzyme of the retroviridae

chimpanzee

original source of human immunodeficiency virus

• sexual contact

• perinatal

• transplacental

• breastfeeding

• blood transfusion

• organ transplantation

• sharing of needles

• needle stick injury

mot of human immunodeficiency virus

Gp21

this component of the HIV virus envelope binds to CD4 receptors on T cells

• targets CD4 T cell (Th17 subsets)

• decrease in number

• loss of cell mediated immunity

• decrease antibody production

• upportunistic infection

pothogenesis of HIV

• Freddie Mercury

• Magic Johnson

artists infected with HIV

• Pneumocystic pneumonia

• Kaposi’s Sarcoma

complication of HIV

acute HIV

flue-like symptoms that occurs days to weeks after contracting HIV

chronic HIV

also known as the latent or asymptomatic stage; can last for several years

AIDS

occurs when CD4 cell count falls below 200-cells/mm3

AIDS

makes a person vulnerable to opportunistic infections and AIDS-defining conditions

• SARS-1 virus (2003 epidemic)

• MERS-COV (2015 epidemic)

• SARS-2 (COVID-19 2020 pandemic)

viruses under coronaviridae

coronavirus

virus with spikes that are club shaped around the envelope

• respiratory droplets

• airborne

• fomites

mot of coronavirus

horseshoe bat

reservoir host of COVID-19

civet cat

intermediate host of SARS-1

pangolin

intermediate host of COVID-19

camels

intermediate host of MERS-COV-2

ground glass

lungs of the patient with coronavirus has an appearance of

2-10 days (mean 5 days)

incubation period of SARS

SARS COV-1

virus that causes severe acute respiratory syndrome

MERS-COV

virus that causes the middle east respiratory syndrome

ACE2 receptors

where does the SARS COV-1 binds?

CD26

where does the MERS-COV binds?

ACE2

where does the SARS-COV2 binds?

SARS-COV2

virus that causes covid19

fecal oral

mot of poliovirus

poliomyelitis

disease caused by poliovirus

poliomyelitis

signs and symptoms of this disease is fever, vomiting, diarrhea, nausea, vomiting then will develop muscle pain, back and neck stiffness

• ingestion of food and water contaminated

• GIT

• lymphatic

• blood

• replication

• anterior motor horn of spinal cord

• destruction

• nerve damage

• muscle atrophy since nerve can no longer stimulate contractions

pathophysiology of poliovirus

32nd president of the US, Franklin D. Roosevelt

famous person who got infected with poliovirus

• respiratory droplet

• direct contact with saliva

• fecal oral

mot of coxsackie virus

• coxsackie a

• coxsackie b

two main groups of coxsackie virus

hand, foot, and mouth disease

disease caused by coxsackie a

hand, foot, mouth diseae

common in infants and children less than 5 years old

• myocarditis

• pericarditis

disease caused by coxsackie b

fecal oral

mot of hepatitis a virus

• fever

• jaundice

• loss of appetite

• RUQ pain

• diarrhea

symptoms of hepatitis a

• ingestion of food and water contaminated

• GIT

• portal vein

• liver

• virus replicates in the liver

• activation of adaptive immunity

• cytotoxic t cell

• damage to liver cells

pathophysiology of hepatitis a virus

• poliovirus

• coxsackie virus

• hepatitis a virus

viruses under pecornaviridae

fecal oral

mot of hepatitis e virus

subclinical infection

epidemic in third world country

hepatitis e virus

virus that causes subclinical infection

hepatitis e virus

virus under hepeviridae

fecal oral

mot of norovirus

viral gastroenteritis

disease caused by norovirus

• fever

• abdominal cramping

• vomiting

• diarrhea (watery)

symptoms of norovirus

norovirus

common cause of diarrhea outbreak in cruise ships

norovirus

virus under caliciviridae

rotavirus

virus under reoviridae

fecal oral

mot of rotavirus

norovirus

virus that causes viral gastroenteritis in adults

rotavirus

virus that causes viral gastroenteritis in children

• fever

• abdominal cramping

• vomiting

• diarrhea (watery)

symptoms of rotavirus

• ingestion of contaminated food and water

• resist stomach acid

• small intestine

• destruction of villi

• black sodium reabsorption, increase potassium lost

• dehydration and electrolyte imbalance

pathophysiology of rotavirus

influenza virus

virus under orthomyxoviridae

• respiratory droplet

• direct contact with respiratory secretions

mot of influenza virus

• fever

• chills

• headache

• body malaise

• sore throat

• cough

• increase nasal discharge

symptoms of influenza

• influenza a

• influenza b

• influenza c

three types of influenca

• pandemic

• avian flue / bird flue

what does influenza a causes?

influenza a

what caused the spanish flue of 1918

• epidemic

• no animal reservoir

what does influenza b causes?

influenza c

influenza that is mild and does not cause outbreaks

influenza b

influenza that can cause epidemics but no animal reservoir

influenza a

influenza that can cause pandemics and avian flue/bird flu

• respiratory discharges

• airborne

• direct contact with nasal and throat secretions

mot of measles virus

• fever

• cough

• conjunctivitis

symptoms of measles

rubeola

medical name of measles

measles

cephalocaudal (head to toe) brick red rash and fades the same pattern

brick red

color of the rash of measles

koplik’s spot

what to check for measles

koplik’s spot

this is present in the mouth at the cheeks near the second molar

measles virus

vaccine for this virus provides a lifelong immunity

• respiratory droplets

• direct contact with saliva

mot of mumps virus

• parotitis (parotid gland)

• orchitis (penis)

present when you have mumps

• virus attaches to the upper respiratory tract

• blood

• parotid gland, testes

pathophysiology of mumps virus

• measles virus

• mumps virus

viruses under paramyxoviridae

rabies virus

virus under rhabdoviridae

bullet shaped

what is the shape of the rabies virus

animal bite

mot of rabies virus

• dogs

• cats

• skunk

• racoon

• bats

reservoir of rabies virus

encephalomyelitis

rabies can cause

respiratory center dysfunction of the brain

how does rabies virus cause death?

• starts with fever

• headache

• body malaise then progressing to spasms

• salivation

• restlessness

• changes in behavior

• hydrophobia

symptoms of rabies virus

• animal bite

• virus replicates in wound

• peripheral nervous system

• spinal cord

• brain

• destruction of respiratory center

• death

pathophysiology of rabies virus

15-100 mm/day

retrograde transport of rabies virus

ebola virus

virus under filoviridae

• direct contact with body fluids

• dead bodies from those who died from the disease

• fomites

• contact with infected bats and primates (apes/monkeys)

mot of ebola virus

fruit bats

natural host of ebola virus

• flue-like with high fever

• diarrhea

• vomiting

• myalgia

symptoms of ebola virus

• endothelial cells

• phagocytes

• hepatocytes

what does the ebola virus target in the body?

• diffuse hemorrhage

• shock

• disseminated intravascular coagulation

complications of ebola virus

dengue virus

virus that is endemic in cebu

DEN 1, 2, 3, 4

four serotypes of dengue virus

mosquito bite

mot of dengue virus

• aedes aegypti

• aedes albopticus

from which mosquito bite is dengue virus