Immune System and Infectious Disease Flashcards
What is the role of vaccines in preventing infectious disease?
Vaccines are designed to induce immunity to an antigen. They are not as strong as immunity achieved from acquiring the infection and booster injections are needed to maintain lifelong immunity.
What is herd immunity?
When 85% of a population receives aa vaccination for the total population to be protected. Polio and smallpox have been eradicated due to vaccinations.
What does the antivaccine movement believe?
that vaccine containing thimerosal (a mercury containing compound used as a perservative) induced autism in children.
What is an attenuated virus?
also referred to as live vaccines. these vaccines contain a weakened virus and a person who receives these vaccines shed the virus and infect non vaccinated persons.
what is B lactamase?
enzymes produced by some bacteria which confer resistant to beta lactam antibiotics by cleaving the antibiotic and making it ineffective. there are 3 types of these enzymes
what are the three types of b lactamase enzymes?
extended spectrum B lactamases (ESBL), carbapenemases, and Amp C B-lactamases.
what is the new delhi metallo b lactamase?
the new delhi metallo b lactamase gene and the colistin resistance 1 gene have spread globally and the presence of one or these genes with other resistant genes can confer pan antibiotic resistance. people can die from infections with bacteria that have these resistant mechanisms.
what is MRSA?
methicillin resistant staphylococcus aureus produces a b lactamase which makes it resistant to penicillin. MRSA also carries the mecA gene which provides resistance to methicillin. it is resistant to aminoglycosides by producing aminoglycoside modifying enzymes, producing excessive para aminobenzoic acid, and through the spontaneous mutation of rRNA which has a lower affinity for antibiotics.
what does the vanA gene do?
the vanA gene provides resistance to vancomycin by decreasing the binding sites of the peptidoglycan for vancomycin.
