Who doesn’t hate mosquitoes, especially this time of year? Turns out Bill Collins doesn’t. In fact, Collins has spent most of his 84 years studying the pesky creatures. More specifically, the entomologist has studied their role in the spread of malaria, a disease caused by a parasite that commonly infects a certain type of mosquito. Earlier this month, Collins retired after four decades of working with mosquitoes at the Centers for Disease Control and Prevention where he is something of a legend. But he isn’t going far. He’ll still be around some, staying on at the CDC as a visiting researcher. “I had my fun,” Collins said. “It is up to the next group of people to continue. They will do a great job.”

Q: Why is working on malaria fun for you?

A: I like to work with things I can see. Mosquitoes may bite you but they are big enough to see without a microscope.

Q: Does working on malaria ever get tiring?

A: Malaria is extremely interesting. It is one of the world’s most important diseases. Every year, it infects hundreds of millions of people, mostly in Africa, and kills 600,000 to 800,000 of them. It kills a child every three minutes.

Q: We don’t worry about malaria in this country. Should we?

A: We see about 1,500 cases a year here, mostly from tourists who go overseas and bring it back. That’s not a lot of cases. But we can’t let our guard down. If the disease breaks out, we’ll jump on it and control it.

Q: You said malaria was once prevalent in the South. How did we get rid of it?

A: In World War I, 25 percent of the soldiers who went to training camps in the South came down with malaria. We got rid of it by spraying DDT. Without DDT, we couldn’t have done it.

Q: How do we control malaria today?

A: It is a multi-task effort, including insecticide sprays, screens on windows and drugs. We treat people before they have parasites to infect mosquitoes. We drain swamps before mosquitoes can breed.

Q: You have had malaria yourself, right?

A: I caught it twice in the lab and I didn’t enjoy it one bit.

Q: What has your work entailed?

A: In the last 20 to 25 years, I have worked on vaccines. A vaccine is the best way to control any disease. I found a way to test a vaccine for malaria in the laboratory to see if it will work, so we don’t have to test it in people. Making a vaccine against a parasite is extremely difficult.

Q: Why is a vaccine for malaria so difficult?

A: This parasite changes its coat, so to speak. It is very, very variable. In one village, you can find 10 different types of the parasite. You can’t make one vaccine and have it work.

Q: Are vaccines on the horizon?

A: Not on the horizon, but it will happen. I don’t think I’m going to be around but I think we have laid the groundwork.

Q: Don’t you have a parasite named for you?

A: Actually, there are two parasites named for me. I am very pleased that people thought enough of me to do that.

Q: How do you view the mosquito?

A: I don’t hate the mosquito. They are one of God’s creatures and they have their place in the scheme of things. We have to prevent them from doing us harm.

The Sunday Conversation is edited for length and clarity. Writer Ann Hardie can be reached by email at ann.hardie@ymail.com.