question; - From the case, identify at least one rate, one proportion, and one ratio. -What features of listeriosis pres

[answerhappygod]

question;
- From the case, identify at least one rate, oneproportion, and one ratio.
-What features of listeriosis present epidemiologicalchallenges?
-What type of epidemiological study design was most likely usedin order to recommend a food recall?
-Would Emily have been interviewed even if there were not asuspected outbreak? Explain your reasoning.
-Even if you calculated the incidence rate correctly in theprevious question, it is probably not a true reflection of thenumber of Listeria infections that occur in the United States everyyear; why?
previous question;
What is the overall incidence rate of listeriosis in theUnited States (assume a population of 315,505,000 and express youranswer per 1,000,000 in the population)?)(dont answer)
backstory;
Emily, a Colorado resident in her 20th week of pregnancy, hadbeen running a fever and experiencing muscle aches and diar-rheafor the past two days. When she noticed bright red blood on herunderwear she called her obstetrician, who instructed her to go tothe hospital immediately. While in the emergency room, two sets ofaerobic and anaerobic blood cultures were taken. Unfortunately,during her homwork a fetal heartbeat was not detected. Emilywas most likely experiencing a miscar-riage. Hospital staff put heron a combination antimicrobial therapy consisting of ampicillin andgentamycin. Blood cul-tures revealed that Emily had a Listeriamonocytogenes infection. Laboratory analysis of fetal and placentaltissue also revealed the presence of L. monocytogenes. Oncestabilized, Emily was interviewed about the foods she had eaten forthe four weeks prior to symptoms developing. While it was difficultfor her to recall all food choices over such a lengthy time period,during the interview Emily’s husband mentioned she had been cravingfruit, especially cantaloupe. The interviewer asked a few morequestions about the cantaloupe, and said that someone from thedepartment of health might follow up with Emily. Local healthauthorities were starting to investigate the possibility of anoutbreak of listeriosis. Listeriosis is a nationally notifiablefoodborne illness caused by Listeria monocytogenes, a Gram-positivebacterium. The bac-terium can be found in soil, water, and in anumber of animals. About 10 percent of people carry L.monocytogenes asymptomati-cally in their intestinal tract. Fortyother mammals and about 17 bird species also carry the bacterium.Any food can become con-taminated with Listeria, but cooking andpasteurization kill the bacterium, so raw foods and/or foods thatbecome contaminated after cooking are more commonly sources. Delimeats and hot dogs processed by contaminated packing equipment areprime sources for Listeria, as the bacteria can grow atrefrigerator temperatures and these foods are often insufficientlyheated before serving. Unpasteurized milk products and cheeses areAbout Cases also common sources. Less frequently, raw vegetables,fruits, prepared deli salads, smoked fish spreads, and meat pâtéare sources of infection. According to the CDC, about 800laboratory-confirmed cases of listeriosis occur in the UnitedStates every year. Most are asymptomatic. Clinical cases are mainlyseen in pregnant women and the elderly. Pregnant women are 20 timesmore likely to become infected than nonpregnant healthy adults,likely due to the lowered cell-mediated immunity (selective immunesuppression) that occurs in pregnancy. Listeriosis during pregnancyis especially dangerous since about 22 out of 100 perinatallisteriosis cases result in miscarriage, still-birth, or neonataldeath. The incubation period for listeriosis ranges from 3 to 70days, but symptoms usually appear within a month and can lastseveral days to several weeks. Emily was one of 146 people affectedby the Listeria outbreak in 2011 that killed 30 people. Among the140 outbreak victims that were able to provide information on whatthey ate, 131 (94%) report-ed consuming cantaloupe within the monthbefore becoming ill. Eventually all of the cases were linked tocantaloupes from Jensen Farms.