final sws

Which regions are considered ENDEMIC for V. cholerae? Select all that apply

- Bangladesh - India - Africa

Which of the following coastal cities experienced more than 30 days of sunny day flooding in 2015? Select all that apply.

- Wilmington, NC - Annapolis, MD - Charleston, SC

Which two pathogens covered in this course are harbored by copepods?

-Vibrio cholerae -Guinea worm larvae

Which of the following problems at the Jensen Farms cantaloupe packing facility likely contributed to the Listeria outbreak in 2011? Check all that apply.

-Water pooled on the floor of packing facility -Equipment on the processing line was hard to clean and showed signs of corrosion and accumulated dirt. -Field-warm cantaloupes were not pre-cooled before storage. -Chlorine was not added to the wash water.

Which of the following genetic features are commonly found in pathogenicity-associated islands? Check all that apply.

-adhesin genes -iron acquisition genes -toxin-producing genes -secretion systems -gene regulators

How does UF use reclaimed water? Check all that apply.

-release to Lake Alice -deep well injection -irrigation

What tertiary treatment of wastewater occurs at UF's water reclamation plant? Check all that apply.

-sand filtration -chlorination

After many years of devastating drought, a city in Arizona is considering using reclaimed water for its source of drinking water. You are asked to speak at a public hearing as an expert in waterborne pathogens. What 3 facts would you present in support of using reclaimed water for drinking? free response

-uses less energy to provide -don't have to go far to get it -the process of filtering is the same as getting water from somewhere else

What is the estimated lifetime risk of DEATH from norovirus for the average American?

1 in 5,000

What is the definition of a tolerable risk? What numerical figure would most people consider a tolerable risk (ie. 1 in X chance of death)? Free Response

1 in a million

What ratio BEST describes the relationship of microbial cells to human cells in the human microbiome?

1 microbial cell to 1 human cell

How many V. cholerae cells can a copepod harbor on and within its body?

1,000,000 cells

What is the infectious dose of V. cholerae cells needed to cause cholera?

1,000,000 cells

In general, if an environmental sample contains 1 million bacterial cells, approximately how many phage would you expect to find in that sample?

10 million phages

Approximately how much of the food supply in the United States is imported?

15%

What ratio BEST describes the relationship of microbial genes to human genes in the human microbiome?

150 microbial genes to 1 human gene

How many antibiotics are accepted for use in the USA?

26

How many pathogenicity islands are found in pathogenic Salmonella serovars?

5

How many times will the average American become ill from norovirus in their lifetime?

5

A local swimming pool was closed after a fecal contamination incident. Pool employees removed the offending material and verified appropriate chlorination levels. After 24 hrs you are asked to see if the pool is safe for swimming. Approximately how much water should you collect for testing with a colilert kit?

500 ml

Approximately how much of the fresh produce sold in the US is imported?

60%

The World Health Organization has published (Feb 2017) a Priority List for research and development of new antibiotics for several pathogens covered in this course. Which two covered in Module 1 are listed as a CRITICAL priority?

Acinetobacter baumannii Pseudomonas aeruginosa

What does ABT stand for in science communication?

And But Therefore

Which pathogen is potentially transmitted by dust?

Aspergillis

Which indicator organism does not replicate in the environment?

Bifidobacterium

Biofilms are problematic in drinking water distribution systems. Which reason is incorrect in justifying the previous statement?

Biofilms can harbor primary pathogens.

Which of the following types of historic disease outbreaks is NOT caused by a waterborne pathogen?

Black Death (plague)

These two pathogens are most likely to grow well in refrigerated foods.

Camplylobacter spp. and Listeria monocytogenes

Which two pathogens are commonly associated with foodborne illness and antibiotic resistance?

Campylobacter nontyphoidal Salmonella

Describe 4 factors that INCREASE public concern/anxiety when faced with a health risk. Free Response

Catastrophic potential Understanding Effects on children Media attention Victim identity

Which of the following is used in the standard treatment of drinking water, but not in the standard treatment of wastewater?

Chlorination to kill microorganisms.

Toxin producing organisms that are NOT pathogens are:

Cyanobacteria and Clostridium botulinum

In the first week we watched an advertisement for "live" water that was untreated spring water from Oregon. Which of the following statements is true?

Deep groundwater aquifers are safe for drinking because contaminants are filtered out by the soil profile.

Which of the following organisms would be capable of fermenting lactose with the production of gas?

E. coli

Oligotrophic water bodies encourage the growth of heterotrophic bacteria, which may include pathogens.

False

Who was the first scientist to actually observe Vibrio cholera cells under a microscope and formally describe them?

Fillipo Pacini

In the Ecuador case study, a road was built between Colombia and the coast of Ecuador. Which of the following is NOT a reason for the observed increase in diseases after construction

Foreign tourists introduced new pathogens to which local Ecuadorians had no genetic resistance.

Where is the water reclamation facility on UF's campus?

Gale Lemerand Drive

The Food Safety and Modernization Act has given the FDA a legislative mandate to require comprehensive, prevention‐based controls across the food supply. Which of the following tools is NOT part of the new law?

Increase the amount of produce imported from other countries.

Which pathogen can replicate within amoeba?

Legionella

Which pathogen is most likely to be found in raw foods like unpasteurized milk?

Listeria

Identify the most desirable pH level and form of residual chlorine for proper chlorination of water.

Low pH; hypochlorous acid (HOCl)

In a genome of an alien bacterium, a mutation in the sequence THE BIG CAT ATE RED RAT led to a new sequence THE BIG COD ATE RED RAT (i.e. there is a new amino acid). This bacterium is now resistant to aminoglycosides. What is the most likely explanation of the mechanism of resistance:

Modification of the target of the antibiotic

Match the predators and their predatory strategy.

Myxococcus - wolf pack Bdellovibrio bacterivorous - periplasmic invasion Bdellovibrio exovorus - epibiotic

Which of the following parasites can only cause an infection by entering through the nose?

Naegleria

Forty marine bacterial isolates were patched on this TCBS plate. Which of the following interpretations of the growth results is true?

Nine isolates formed yellow colonies, these isolates are likely vibrios that can ferment sucrose.

Which of the following pathogens survives well in cold temperatures:

Norovirus

All of the following have contributed to the rise in antibiotic resistance in bacteria EXCEPT:

Pathogenicity islands

Which of the following potential constituents of wastewater is not currently addressed in treatment:

Pharmaceutical products

Which of the following bacteria produce ice nucleating proteins?

Pseudomonas syringae

Which of the following is not a chromatography technique?

RFLP

An outbreak of foodborne illnesses has been linked to fresh tomatoes from Florida. You suspect the culprit is either pathogenic E. coli or non-typhoid Salmonella. You spread a sample of contaminated tomatoes onto XLD media and after 24 hours of incubation, you observe yellow colonies and the agar around the colonies is yellow. How do you interpret the results of the XLD agar test?

The agar and colonies have turned yellow due to the presence of coliforms that are fermenting sugars and producing acid as a biproduct.

I have spread a culture of E. coli on MacConkey Agar with Sorbitol and observe both clear colonies and pink colonies. Which of the following is true?

The clear colonies are likely E. coli O157:H7

Colilert tests are a fast and easy way to test contamination in drinking water. Suspect water is mixed with a reagent and observed for two indicators. Indicator one is yellow and indicator two is fluorescent under UV light. Which of the following statements is true?

The fluorescent indicator shows the potential presence of E. coli.

This image shows Vibrio cholerae cells attached to phytoplankton. The vibrios are labeled with an immunofluorescent probe. How does this probe stick to the cells?

The fluorescent probe is attached to an antibody of the V. cholerae antigen.

Why is this course focused more heavily on gram-negative bacteria rather than gram-positives?

The majority of pathogenic microbes adapted to the human gut are gram-negative.

You have just combined ONPG and drinking water. After a bit of time, you see that the water has changed color from clear to yellow. What does this indicate?

The presence of coliforms

Which of the following statements is true of size exclusion chromatography?

The small molecules will travel through the porous particles and elute last.

A blood sample taken from a person tests positive for the antigen to Vibrio cholerae. Which of the following interpretations is correct?

This person was exposed to V. cholerae recently.

What are the most likely stressors experienced by bacteria in air?

UV radiation, desiccation, and low nutrients

Which of the following was NOT part of the approach to eradicate the Guinea Fireworm?

Vaccines were developed to minimize effect of fireworm

Which of the following waterborne pathogens does NOT always cause diarrhea?

Vibrio vulnificus

How did E. coli O157:H7 become a pathogen?

acquired shiga toxin gene from a phage

Serotyping distinguishes strains of pathogens based on what characteristics?

antigens found on flagella and outer membranes

Which of the following groups do NOT contain known predators of bacteria?

archaea

Complete the famous quote by Theodosius Dobzhansky: "Nothing in _____ makes sense, except in light of ____."

biology; evolution

Which of the following foods consumed in the US are most likely to be imported from other countries? Select all the apply.

chocolate fresh fruit coffee seafood

An outbreak of a gastrointestinal illness on the coast of a South American country caused by drinking water that is contaminated with human waste is most likely:

cholera, caused by Vibrio cholerae

Which components of soil have charged properties?

clays and humics

How do bacteria acquire new genetic material? Select all that apply.

competence pathogenicity islands conjugation transposons

Which eukaryotic parasite has been tracked by the CDC for multi-state outbreaks over the last four years (2014, 2015, 2016, 2017)? Note that in 2016 and 2017, the source of the contamination was never determined.

cyclospora

Which of the following is not a route of transmission of pathogens?

farm runoff

pH indicators added to culture plates often change color with acidification. What metabolic process does this indicate?

fermentation

The needle-like type-3 secretion system has homology with what other bacterial structure?

flagella

Legend: Growth of S. enterica serovar Newport (open symbols) and E. coli O157:H7 (shaded symbols) on A. thaliana shoots (triangles) and roots (circles). Which of the following statements summarizes the data presented in the figure above:

in plant rhizosphere, cell numbers of Salmonella and coli increase ~10,000-fold within 2 days

At what time of year does the highest incidence of cholera occur in Bangladesh? free response

in the fall

Microbes in the cryosphere face each of the following abiotic stressors EXCEPT:

iron limitation

Throughout the 20th century, strains of Salmonella have been used as agents of bioterror. Which property makes Salmonella an attractive tool for bioterrorists:

many strains of Salmonella have a very low infectious dose

Once biofilms are irreversibly attached, which of the following items could be used to disrupt the biofilm?

nitrous oxide

While Norovirus is responsible for more than half of all food-borne illnesses in the US, which bacterial pathogen is responsible for more hospitalizations and deaths due to food-borne illness than Norovirus?

non-Typhoid Salmonella

You suspect a high bacterial load in a water sample. You decide that a heterotrophic plate count (HPC) is the first test to be carried out. HPC will detect and enumerate:

only those bacteria that can grow on that medium under these incubation conditions

Which culturing augmentation does not inhibit environmental bacteria?

pH indicator

Which of the following statements regarding the cation exchange capacity of soil is TRUE?

positively charged particles adhere to clay particles

What are the most likely stressors experienced by bacteria in soil?

predation, patchy nutrients, and competition with other bacteria

Some detection media contain bile acids to:

prevent growth of environmental bacteria

Search the CDC multi-state foodborne outbreaks site for the year 2016. What two food products tracked by the CDC were contaminated with Hepatitus A?

raw scallops in Hawaii strawberries imported from Egypt

These covers on the sidewalk next to McCarty Hall A allow access to water lines. The blue cover indicates potable water. What does the light purple cover indicate?

reclaimed water

Which nucleic-acid based technique will detect Norwalk virus:

reverse transcription PCR with specific primers

Which of the following pathogens has the most multi-state foodborne illnesses listed on the CDC website?

salmonella

Which of the following techniques will help separate DNA from low molecular weight contaminants:

size exclusion chromatography

Which list is correctly ordered from MOST abundant microbial biomass per unit volume to LEAST abundant microbial biomass?

soil > coastal ocean > mid-ocean gyre > Florida springs

Which of the following microbial activities are known to be regulated by quorum sensing?

swarming motility, toxin production, and release of extracellular enzymes

Scientists are usually trained to talk about their research by describing the background, methods, results, and finally ending with conclusions. If we want to speak to the general public, what should we really start with?

the bottom line

We use chlorination to make drinking water safe for human consumption. Why can't the general public perform chlorination at home? What are the disadvantages of chlorination to humans? Free Response

the general public may not understand how to apply the proper amount of chlorination since too much chlorination can be toxic.

Using culture-based methods to identify pathogens is MOST suitable when:

the pathogen has known growth requirements

The inability to cleave fluorogenic substrate MUG allows to distinguish:

total coliforms from fecal coliforms

Which of the following practices have likely contributed to the rise in multi-drug antibiotic resistance? Select all that apply.

use of antibiotics in animal feed use of antibiotics for cold or flu use of antibiotics in dish soap use of antibiotics in hand soap

To test whether a presumed virulent strain of E. coli is capable of utilizing lactose and produces extracellular Shiga toxin, a multiplex PCR was carried out using primers specific for the stx gene (which encodes Shiga toxin) and the lacZ gene (encodes an enzyme involved in lactose utilization). The results of a PCR are shown below: Lane 1 (control): Template: a strain of E. coli known to produce Shiga toxin. Primers: specific to the shiga toxin gene, Stx1 and Stx2 Lane 2 (control): Template: a strain of E. coli known to be able to utilize lactose. Primers: specific to the lacZ gene, LacZ1 and LacZ2. Lane 3 (control): No template; a mix of the 4 primers Lane 4 (sample): Template: a presumed virulent strain of E. coli. Primers: Stx1, Stx2, Lacz1 and LacZ2 The same E. coli strain as in Lane 4 was then tested using a direct ELISA test for the presence of the Shiga toxin and was also plated on a modified XLD medium which only contains lactose and lysine and no sucrose or xylose. What results would you expect from these tests:

will test positive with ELISA, will turn yellow on the modified XLD