Why are opportunistic pathogens that form biofilms on indwelling devices particularly difficult to eradicate and a common cause of device-associated HAIs?

Design a perioperative infection prevention bundle for elective surgeries that synthesizes microbiology concepts (normal flora, portals of entry, opportunistic pathogens, and disinfectant resistance). Which bundle best addresses these concepts comprehensively?

A hospital performs 2,500 surgeries in a year. Using the lesson's statistic that surgical procedures account for approximately 22% of HAIs and the overall HAI rate is 3% of patients, estimate approximately how many HAIs in the hospital year are surgical-procedure-related. (Assume each surgery represents one hospital admission for this calculation.)

Which epidemiological study type is primarily used to describe the distribution of cases by person, place, and time and to generate hypotheses rather than test them?

A case-control study produced this data: Cases: exposed 40, unexposed 20. Controls: exposed 30, unexposed 80. Calculate the odds ratio and recommend the most appropriate public health interpretation.

A randomized trial found lower illness in the intervention arm, but 20% of participants in the intervention arm did not use assigned sanitizer while 5% in control obtained sanitizer independently. Which analysis approach best preserves randomization and estimates effectiveness?

Which of the following best summarizes the contrast between large respiratory droplets and microscopic droplet nuclei?

In a kitchen, raw chicken is cut on a board, the board is not washed, and a salad is prepared later on the same board. Which items served as vehicles in this chain and what single immediate action would best prevent transmission?