R5 and X4 virus (HIV types)R5 virus uses CCR5 for viral entry and is considered macrophage-tropic. R5 is the predominant HIV type.
X4 virus uses CXCR4 for viral entry and is considered T lymphotropic.→ Patients with X4 virus cannot be treated with HIV medications that target CCR5 (☆eg, maraviroc) because the X4 virus uses CXCR4, not CCR5, to enter cells. microbiologyUWorld HirotoShishido
oseltamiviramantadine→ impairs uncoating or disassembly of influenza A virion after host cell endocytosis
The virus replicates locally within the muscle tissue of the bite wound for several days or weeks and then travels in a retrograde fashion microbiologyUWorld HirotoShishido
Rocky Mountain spotted fever
endemic location, characteristicsNorth Carolina
headache, fever, rath→typically starts at wrists and ankles and then spreads
to trunk, palms and soles microbiologyUWorld HirotoShishido
transmission, risk factors, manifestationstransmission→ ingestion of raw oysters or ☆wound infection
substitute for bacitracin test for GASBecause the bacitracin test is not very specific for S pyogenes, it has been replaced in many laboratories by the ☆pyrrolidonyl arylamidase (PYR) test; S pyogenes is PYR-positive.
prevention of neonatal tetanusPrevention of neonatal tetanus focuses on ☆vaccinating women who are pregnant or may become pregnant with inactivated tetanus toxin (tetanus toxoid).
Appropriately vaccinated women provide transplacental lgG to the fetus, which decreases the incidence of neonatal tetanus by approximately 95%. microbiologyUWorld HirotoShishido
mechanism of resistanceMutations leading to underexpression of KatG(which encodes ☆bacterial catalase- peroxidase needed to convert INH to active metabolite)