The science behind superbugs

When penicillin, one of the world’s first antibiotics, was discovered in 1928, doctors realized our environment offers tools that could cure infectious disease.

But today, antibiotic overuse is creating a health crisis with the evolution of drug-resistant pathogens, sometimes called superbugs. If no action is taken, drug-resistant diseases could cause 10 million deaths annually by 2050, according to a report released this year by the World Health Organization.

Jane Lucas, a soil microbiologist at the University of Idaho, will speak Monday in Colfax about the latest research into drug-resistant microbes, questions scientists want to answer and ways people can take action.

“Antibiotic use and misuse is definitely a concern, but I also think people have the power to make good choices and be responsible. If we act now, we’re going to save a lot of lives in the future,” Lucas said.

Would you explain the difference between naturally occurring antibiotics versus antibiotics that humans introduce to the environment?

Almost all the antibiotic compounds we use today are either inspired by or a direct copy of compounds found in nature. People go to nature to find microbes that produce these compounds to out-compete their competitors. Humans have found which organisms can make them, and we’ve created a whole pharmaceutical industry around that.

The big question we still have is how often these microbes make these compounds in nature.

We don’t know.

The ones grown in laboratories are going back into the land through wastewater and agricultural practices. When you take a course of antibiotics, or we feed them to animals, most of it is probably not going to be used by your body, so it just goes in one end and comes out the other. It leaves through the sewer system or animals eliminate freely in fields, leading to a continuous input of human-derived antibiotics. It can be less than a percent to 100 percent of the dose entering our ecosystem.

Do you have any statistics you could share about increased levels of antibiotics in the soil? Is the increase more from use in humans or animals?

It’s a little hard to piece those out, but about 80 percent of all the antibiotics we produce today are given to animals, so the vast majority of antibiotics we use are given to animals. It’s pretty safe to say more introductions are coming from ag industries than from humans, but of course humans are the reason that is happening.

Why are antibiotics being used so heavily in animal agriculture — to prevent disease?

In a factory farming situation with animals close together in pens, disease can spread easily, but the main driving force for why people are using antibiotics is growth promotion. Antibiotics administered at what they call a “sub-therapeutic level” can increase growth by an average of 5 percent.

It’s pretty well known that in areas where farming is occurring, the higher levels of antibiotic resistance are occuring. The increase in antibiotic resistance can be found in the soil and waterways and also in the people working with those animals, unfortunately. There’s a study that said poultry workers are 32 times more likely to have antibiotic resistant E. coli than other people in their community. In soils from cattle farms, we have seen a 5.2-fold increase in antibiotic resistant genes, which is pretty big.

What happens to the man-made antibiotics after they are excreted?

One thing many people don’t know is that antibiotics don’t stay around in the environment for very long. They get broken down and decompose in about a week. What we’re a little more concerned about is that once you’ve introduced these compounds you also shift the microbes in the soil to create a community with a heightened resistance to antibiotics. We don’t know how long those antibiotic-resistant microbes are going to be around. We call it the biogeography of antibiotic resistance.

We also want to know, are there ways we can manage our soil to encourage that resistance to go away? Are there things we are doing besides introducing antibiotics that are increasing antibiotic resistance?

How do these antibiotic-resistant microbes affect our food and water supply?

More likely than not, you are not going to re-consume antibiotic compounds because they decompose quickly, but we know that one in every five multi-drug resistant infections is caused by germs coming from the food and animal industry. So, you eat an apple with antibiotic-resistant organisms on it; if those organisms are in your food, you may have antibiotic resistance in your system as well. You probably already have that, but as you get more and more, you may become more susceptible; you’ve built up your reserve of resistance.

Are there things people can do to protect themselves and the environment?

There are lots of things we can do. Washing your food is one.

Because the meat industry is really the largest consumer of antibiotics, people would need to be intentional about where they’re getting their meat. You can make sure you’re informed about where your food is coming from and know how they’re managing their animals. Most people would say avoid meat that has been given antibiotics for growth production.

We can also encourage our policymakers to put in more regulations about the use of antibiotics. We’re getting better at it, but the fact is that 50 percent of antibiotics are prescribed unnecessarily or misused. We could put in more regulations that encourage more responsible use. For example, you have to know you have a bacterial infection before prescribing antibiotics. That would be a big way to promote broader and longer lasting change.

You should also be very careful about how you dispose of leftover antibiotics. Doctors’ offices will take them so, when you’re getting rid of old drugs and cleaning out your medicine cabinet, make sure they go to the right place and not just into our waterways. !

IF YOU GO

WHAT: “Ecosystem Health in the Age of Antibiotics.”

WHEN: 6 p.m. Monday.

WHERE: The Center at Colfax Library, 102 S. Main St.

COST: Free.

OF NOTE: The presentation is part of Science on the Palouse, where regional experts explore trending topics the second Monday of each month. The event is organized by the library and the Whitman Conservation District. Presentations are geared toward adults but youth ages 10 and older are welcome to attend.