L8 - Mosquito Borne Pathogens Flashcards
What is another name for mosquito-borne viruses?
Arboviruses
Wha are mosquito-borne parasites?
Malaria
Plasmodium
How can pathogens be inoculated at mosquito bites?
deposit saliva and virus
have to start replication before immune response to bite and pathogen
Why have arbovruses increased?
GLOBALISATION -water in tyres on ships
CLIMATE CHANGE
What are the 2 main Aedes mosquitos?
Aedes aegypti Aedes albopictus (asian tiger)
What do mosquitos do that makes them effective disease spreaders?
bite many times
What are some human arboviruses?
Dengue
Chikungunya
Zika
Yellow Fever
What are some animal arboviruses?
BTV
Do arboviruses need to replicate to high levels in the blood?
YES
How do RNA genomes of arboviruses replicate in the cytoplasm?
receptor-mediated endocytosis
acidic pH mechanism for virus material entry
genome looks like cellular mRNA
replicate
translate into polyprotein
What is dengue fever?
spread by Aedes
body pain basically everywhere
When do complications with dengue fever occur?
infected SECOND time with DIFFERENT SEROTYPE
what is severe dengue?
sudden haemorrhagic fever
What is Zika?
infect developing CNS
GBS
microcephaly
What is chikungunya?
severe pain in joints and muscles
re-emerging virus
How is the immune response in the skin helpful for arboviruses?
innate immune response to pathogen
activation of antigen presentation
What part of the virus do PRRs recognise?
unique
common to viruses
essential for life cycle
What are 2 main PRR families?
TLRs - cell surface, endosome
RLRs - cytoplasm
What is the issue with dengue and the immune response?
when reinfected with diff. type, blood vessels haemorrhage
virus igG complex is eaten by phagocytes and infects phagocytes
What is the immune response to arboviruses?
Type 1 IFN stops virus replicating
adaptive immunity can clear infection
What mosquito spreads malaria?
anopheles mosquitos
What happens when infected with Malaria?
fever
can progress to anaemia
What are therapies for Malaria?
artemisinin-based
What are immune responses to Malaria?
adaptive immune responses - Th1, CD8 and IgG
Malaria has variant surface antigens - immune system plays catch up
