This 53:40 minute PBS Frontline report, first aired on Oct. 14, 2014, is in two parts both of which deal with antibiotic resistance. The first part, “The Trouble with Antibiotics”, focuses on antibiotics used in agriculture and the role those antibiotics may have in producing resistance to antibiotics used in treating infections in humans.
The second report is “Outbreak at NIH” which focuses on cases of Klebsiella pneumoniae carbapenemase (KPC) in the Clinical Center at the National Institutes of Health in Bethesda, Maryland, a premier health center. While the first video focuses on a possible cause of antibiotic resistance infections, this second video focuses on a consequence—a deadly outbreak at the hospital.
While “Outbreak at NIH” is primarily about antibiotic resistance, it also allows discussion of the very important topic of hospital-acquired infections (HAI). The outbreak cases of KPC at the NIH hospital were all cases of hospital-acquired infections. Eighteen people became ill and 6 people died in the first outbreak.
If you are showing this within “Something’s Not Adding Up”, you may want your students to watch and discuss both segments to this Frontline report.
Note: The “Outbreak at NIH” segment is also profiled in Frontline’s The Nightmare Bacteria documentary. The Nightmare Bacteria is one of the additional resources for several problem-based learning modules.
Background on KPC
Klebisella sp.is a Gram negative, rod-shaped, non-motile, facultative anaerobic bacteria. It is normally found in the intestines and does not cause disease there. Problems arise in healthcare settings where people are already vulnerable to infections because they are sick, because they are receiving treatments through potentially infected devices, such as IV catheters and ventilators, or have surgical sites which are more easily infected.
Problems also arise because the bacteria have developed a resistance to the carbapenems, a group of antibiotics. Some Klebsiella sp. are able to produce the enzyme carbapenemase which makes them resistant to the carbapenen antibiotics. The “C” in KPC refers to a Klebsiella pneumoniae type that is resistant to the carbapenems. Carbapenems can be the last line of defense against Klebsiella that won’t be killed by other antibiotics. When carbapenems do not work against the bacteria, patients can die.
People become infected with KPC in healthcare settings through person-to-person contact (from patient to healthcare personnel to patient) or by contaminated equipment.
Adherence to strict infection control procedures such as correct hand-washing, wearing protective gear (caps, gowns, gloves, or masks), and correct cleaning procedures can prevent the spread of bacteria or at least minimize the risks.
One of the ways bacteria become resistant is when people do not follow directions when taking antibiotics for a bacterial infection. It is important to finish the entire dose of antibiotics even if symptoms go away and the person feels better. If the patient does not finish the entire dose, some bacteria may still survive and these bacteria can develop resistance.
Make sure your students understand that some bacteria are becoming increasingly resistant to even the strongest antibiotics. This has been identified as a major health problem in the U.S. and around the world. Over 20,000 people die each year from infections caused by antibiotic resistant bacteria and over 2 million people get sick from them. According to expert health organizations, what has been termed as “nightmare infections” are caused by bacteria that we now can’t kill.
Part I. The Trouble with Antibiotics
- It is estimated that 70% of antibiotics sold in the U.S. are bought by farms. Given the serious issue of antibiotic resistance, why are antibiotics used on farms? What does the veterinarian in the video say is his primary goal in using antibiotics?
The veterinarian in the video commented that his goal in using antibiotics is to prevent disease from happening. There are 100,000 chickens on the farm shown in the video and the vet said that if one chicken gets sick, it spreads quickly through the 100,000 chicken- population.
2a. The video describes a Flagstaff, Arizona hospital that started seeing an increase in resistant urinary tract infections. Normally healthy young people had gone through various courses of treatment in doctors’ offices, but had not gotten better.
Why was this such a concern?
If the urinary tract infection is resistant, it can get into the kidneys, and once in the kidneys, it can get into your bloodstream. This is condition is called sepsis, a life-threatening condition that can cause multiple organ system failure. Sepsis kills 40,000 Americans every year.
b. What is Dr. Lance Price’s idea about where the infections could be coming from?
He thought that chicken meat could serve as a source of E. coli bacteria that then went on to cause resistant urinary tract infections. He was not concerned about antibiotics on the meat, but antibiotic resistant bacteria on the meat.
c. How did the use of antibiotics on chicken farms develop?
The practice started in the 1960’s when farms were getting bigger and animals were closer together. Disease could spread more easily though crowded environments. Antibiotics were used to decrease chances for disease spread, but it also increased growth. Animals gained the same amount of weight on less feed. This made chicken meat less expensive for the consumers and chicken farmers made more money. The practice of using antibiotics grew.
3a. Dr. Joan Casey, an epidemiologist from University of California, Berkeley, was researching a link between food and human MRSA (Methicillin –resistant Staphylococcus aureus) infections in central Pennsylvania.
What had she noticed about MRSA in Europe?
She found out about research in Europe that described MRSA cases travelling from pig farms to cases of human MRSA.
b. What had she noticed about MRSA in central Pennsylvania?
She collaborated with Dr. Brain Swartz, a Senior Researcher at Gesinger Medical Center in Pennsylvania. They got millions of health records and noticed that MRSA cases had increased dramatically from 2001-2009 and that patients weren’t typical MRSA patients. Then they noticed that the MRSA cases were concentrated in areas that had large swine farms nearby.
- Farms used millions of gallons of manure on crops fields. Scientists wondered if the manure could contain undigested antibiotics and anti-resistant bacteria that would lead to increased MRSA infections. What did their research show?
Their research and analysis showed that there were 38% more MRSA infections in the area tested than would be expected.
Note: Your students might ask why they did not test the manure to find out if the anti-resistant bacteria were present. The scientists were not given access to the privately-owned farms and were not allowed to test the manure. They could make the link of increased MRSA infections in the area to the millions of gallons of manure from antibiotic-fed swine, but could not test the manure.
- What has been the Federal Drug Administration’s policy on antibiotic use in agriculture?
The FDA tried to decrease antibiotic use about 40 years ago, but the opposition from lobbyists was too strong. The lobbyists recruited the politicians who controlled the FDA budget and threatened to cut their budget if there wasn’t proof of the link between antibiotic agricultural use and human infections by antibiotic resistant bacteria.
6a. The Flagstaff researchers tested chicken meat from grocery stores for E. coli. What did they find?
They found out that 20% of the meat tested had disease-causing E. coli and about one-third of the bacterial cultures grown were antibiotic resistant.
b. How did they establish a link between the resistant E. coli infections in humans to the food supply?
They had the hospital send them 1200 samples of bacteria from the urinary tract infections (UTI) of patients. They tested the bacterial DNA using genome sequencing to see if the chicken meat bacteria matched the human infection bacteria.
At the time of the video they were halfway through the data, but had established a link between about half the UTI infections and the meat supply.
Part II: Outbreak at NIH
This video report starts at approximately 37:14.
- How did the outbreak at the National Institutes of Health (NIH) Clinical Center start?
It was brought into the hospital when a woman with lung disease was transferred from a hospital in New York to the Bethesda hospital for treatment. She was carrying KPC.
- Dr. David Henderson, Deputy Director of the hospital, said they went into the epidemiology equivalent of “Defcon 5”. What did they do to combat this one case of KPC?
They said they implemented every technique they had and the patient was placed in “enhanced isolation” in the ICU.
3a. The “Defcon 5” procedures seemed to work. The patient got better and no new cases of KPC occurred. Then, five months later, KPC turned up in another patient’s respiratory culture. The patients were not in hospital at the same time and did not have the same care-givers. They started having other cases of KPC in ICU. They had another outbreak.
What did they now try to stop the outbreak? Did it work?
They tried combinations of different types of antibiotics and tried giving the antibiotics orally and by IV. They got experimental antibiotics and created separate units to isolate the KPC patients. They had robots to disinfect all areas. None of it worked.
b. Dr. Julie Segre, a geneticist at NIH described how they found the cause. What turned out to be the cause of this second outbreak? How did they find out?
They compared the DNA of the KPC samples and tested many people at the hospital. They found out that people who showed no signs of infection were carrying the bacteria—“silent carriers”. The infection spread beyond ICU and into the general patient population.
4a. 19 year old Troy Stulen had a genetic condition that caused him to have serious gastrointestinal problems and he had a bone marrow transplant to help relieve this condition.
How did he end up getting KPC?
They think that Troy probably got infected when a patient from the first outbreak came back to the hospital during a routine follow-up visit, but they are not sure how Troy came into contact with the infection.
b. What did they do for Troy to stop the infection and why didn’t it work?
They started him on colistin, a powerful but toxic antibiotic. At first it appeared to be working, but the infection had mutated and the colistin was no longer effective.