Exam 4 - Lecture 21 Flashcards
what are the main modes of pathogen transmission?
- airborne
- contact (direct and indirect)
- vehicle (food and water)
- vector borne (arthropod and zoonotic)
- vertical
the disease influenza is caused by the:
influenza virus
the first record pandemic of the flu was recorded in what year?
1580
the worst flu pandemic killed ____ million people in 1918. it’s aka the __________ flu.
- 50 million
- Spanish flu
what are the three groups of influenza?
A, B, and C
true or false: influenza has a DNA segmented genome.
false; its an RNA virus (but yes, segmented)
what family does the influenza virus belong to?
Orthomyxoviridae
influenza virus is typically ___ segments of _____
8 segments of RNA
influenza typically has how many genes/proteins?
11
what are the two viral proteins in the envelope of the influenza virus?
- hemagglutinin (HA; 16 types)
- neuraminidase (NA; 9 types)
strains of influenza are classified based on their combination of _______ types (H1N1, H3N2, etc.).
HA/NA
in viral replication, HA attaches to _________ ______ ___________
sialic acid receptors
in viral replication, NA protein does what?
cleaves receptors, releasing new virions
what is antigenic drift?
- accumulation of mutations in a strain
- nucleotide/amino acid changes
what is antigenic shift?
- reassortment of genomes (8 RNAs)
- two different strains of flu viruses infect the same cell and are incorporated into a single new capsid (like human + pig or bird strain)
the best line of defense against influenza is:
vaccination
what are two antiviral drugs found in flu vaccines?
- Tamiflu
- NA inhibitors (prevents release of new virions)
what are arboviruses?
- arthropod-borne diseases
- viruses transmitted from one vertebrate to another by bloodsucking arthropods
_____ _______ is spread through the bite of an infected Aedes species mosquito. it can also be spread by what?
- zika virus
- sex with an infected person, pregnant woman to fetus, and laboratory exposure
many people infected with zika virus are ____________.
asymptomatic
zika virus infection during pregnancy can cause:
microcephaly and other severe birth defects
how does contact transmission occur?
- coming together or touching of source/reservoir and host
- direct and indirect
what is direct contact transmission?
physical interaction between source and host
- kissing, touching, sexual contact
- contact with bodily fluids, open wounds
what is indirect contact transmission?
- involves an intermediate (usually inanimate)
- eating utensils, bedding, syringes
what does AIDS stand for?
acquired immune deficiency syndrome
what causes AIDS?
human immunodeficiency virus (HIV)
AIDS only develops at _______ stages of HIV infection.
latter
true or false: AIDS allows opportunistic pathogens to infect.
true
HIV leads to the __________ of the immune system.
collapse
what family is HIV part of? what kind of genome does it have?
- Retroviridae family
- RNA (+) virus
how many copies of its genome does HIV have?
two
the attachment of the HIV virion to human cells is mediated by _______, which attaches to CD4 receptors
gp120
what are the core proteins of the HIV virion core?
- P24
- P17
- P9
- P7
what is the precursor polyprotein for the virion core proteins of HIV? this polyprotein is processed by _____ __________
- Gag
- HIV protease
what are three important enzymes that HIV carries into the host cell?
- reverse transcriptase
- integrase
- protease
the RNA genome of HIV is __________ transcribed into ______, which integrates into human genome as a __________.
- reverse
- dsDNA
- provirus
true or false: HIV cannot remain latent/have asymptomatic effects.
false; it can totally do that
what classifies the acute stage of HIV-related symptoms?
- 2-8 weeks after infection
- most experience brief illness called acute retroviral syndrome
- rapid multiplication and dissemination of virus throughout the body
what classifies the chronic symptomatic stage of HIV-related conditions?
- viral replication continues
- can last from months to years
- number of CD4+ cells in blood significantly decrease
what major groups of viruses are the main causes of gastroenteritis?
- rotavirus
- adenovirus
- astrovirus
- norovirus
what are Select Agents?
RNA viruses that can potentially used as bioweapons
- Ebola and Marburg viruses
- Rabies virus
what family is the Ebola virus that causes Ebola hemorrhagic fever a part of? what kind of genome does it have?
- Filioviridae
- single stranded, negative sense RNA
Ebola hemorrhagic fever is ____% fatal and causes __________ _______________
- 80%
- internal hemorrhaging
what is the name of the Ebola vaccine? (page 53, lots of other info there)
Ervebo
