Lecture 40- Viral diseases Flashcards
Describe the 3 main features of the herpes virus
has DNA
cell fast- enters your nerve cells and incorperates it’s DNA into yours
grows latent- can be reactivated when immune system goes down (stress)
Describe human herpes virus type 1
herpes simplex 1 cold sores (herpes labialis) SYMPTOMS blisters for 1-2 days crusts for up to 3 weeks TRANSMISSION infected as a child 90% of population has it 4 million americans are symptomatic TREATMENT acyclovir COMPLICATIONS gingiva stomatitis- blisters inside the mouth herpetic keratis- occurs in eyes, vision loss. causes 30% of neonatal encephalitis (STORCH) which can lead to retardation
Describe human herpes virus type 2
Herpes simplex 2 Genital herpes OCCURRENCE 20% of population have this 40 million americans SYMPTOMS pain nausea blisters- start in genitals move to butt and legs symptoms return every 2-4 weeks COMPLICATIONS known associate of cervical cancer causes 70% of neonatal encephalitis (STORCH) TREATMENT acyclovir
Describe human herpes virus type 3
varicella & zoster
chicken pox & shingles
CHICKEN POX
90% of children are exposed
there is a vaccine- zostavax
spreads through micro aerosols or contact with blisters
once you get it, you never get it again (long term immunity)
incubation is 1-3 weeks
can spread 1-2 days before symptoms, infectious 6 days after last crop (blister)
COMPLICATION
reye’s syndrome- aspiring can make fluid accumulate in brain leading to death
SHINGLES
relapse of the chicken pox
30% of people who had chicken pox get it
blisters spread chicken pox (NOT shingles)
blisters last for 2-4 weeks, follow the nerves
COMPLICATIONS
post herpetic myalgia- pain from shingles stays for a year
treatment is acylovir
Describe the disease caused by human herpes virus type 4
epstein barr virus causes infectious mononucleosis (mono) transmitted by saliva SYMPTOMS severe sore throat lyphadenopathy- swollen lymph nodes (esp. cervical/neck) lymphocytosis- increase in lymphocytes COMPLICATIONS burkett's lymphoma- swollen abdomen and cheeks, B cell malignancy (common in Africa)
Describe human herpes virus type 5
cytomegalovirus
most people are asymptomatic
some get mono called cytomegalovirus mononucleosis
SYMPTOMS
sore throat
cervical lymphadenopathy- swollen lymph nodes around neck
lymphocytosis- increase in lymphocytes
DANGEROUS FORMS OF CMV
congenital cmv- mom to baby (STORCH)
perinatal cmv- baby picks it up moving through vagina, less intense for big babies
disseminated cmv- spreads through the body. problem for immunocompromised patients (AIDS)
Describe human herpes virus type 6
human t lymphotrophic virus
causes roseola- rash and fever in young babies (<1 year old)
related to MS
Describe human herpes virus type 7
orphan virus- no symptoms except maybe mild rash
Describe human herpes virus type 8
linked to karposi’s sarcoma- causes hemorrhagic tumors in AIDS patients
Describe the general symptoms of hepatitis
liver damage- possibly due to heavy drinking or INH antibiotic
fever
jaundice- yellow skin due to bile pigments
brown urine
Do most hepatitis viruses use RNA or DNA? which doesnt follow the trend?
RNA
hep. B uses DNA
Describe hepatitis A
RNA
aka. infectious hepatitis
spreads through oral/fecal
acute- lasts 2 to 3 weeks then symptoms end
Describe hepatitis B
DNA aka. serum hepatitis spreads through blood acute in most, chronic in 6% of people vaccinate to prevent 2% mortality rate associated with liver (hematoma) cancer STORCH/placenta disease can last 1 week on a fomite can be "cured" by sustaining viral replication using interferon alpha and tenofovir (a neucleoside reverse transcriptase inhibitor)
Describe hepatitis C
RNA
aka classic non A, non B
spreads through blood
80% of patients are chronic
no vaccine because the virus varies a lot
can’t detect in blood until 70-80 days after infection
STORCH/placenta disease
treated with peg interferon, ripaverin, and telaprevir (protease inhibitor) in 79% of people
Describe hepatitis D
RNA
aka delta virus
not infectious alone, need to get it with hepatitis B
get the hepatitis B vaccine to prevent infection
Describe hepatitis E
RNA
infectious non A, non B
spread through oral/fecal route
higher mortality rate in pregnant women than hepatitis A
Describe hepatitis F
a variation of hepatitis C
Describe hepatitis G
RNA
spread through blood
symptoms vary a lot
co-infection with hepatitis C or AIDS will slow down the progression of that virus
Describe the etiology of human immunodeficiency virus
2 strains- HIV 1 (most common) and HIV 2 (more common in Africa, milder, longer incubation period)
retrovirus- uses reverse transcriptase (takes single stranded RNA and makes double stranded DNA)
has 2 single strands of RNA, capsid, envelope, spikes (which attach to leukocytes)
Describe the morbidity of HIV
worldwide is 45 million people, 15 million of those are children
Describe the mortality of HIV
without treatment ~5% of people survive (because of delta32 mutation on CCR5 gene)
With treatment death rate was 18% in 1998, becomes a chronic condition
Describe the transmission of HIV
unprotects sex
parenteral- coming from blood such as sharing needles
placenta- 30% chance
breast milk
Describe the incubation period of HIV
8 years from HIV+ to AIDS
infects white blood cells, especially CD4 cells. When less that 200 CD4 cells per micro liter you have AIDS
Describe the stages of infection for HIV
CATEGORY A first 3 years mononucleosis like- sore throat, lymphodenapathy (swollen lymph nodes) generally asymptomatic CATEGORY B 4-8 years mildly symptomatic frequent candida albicans infections (thrush) CATEGORY C after 8 years AIDS, symptomatic get lots of diseases that normal people dont get
