An early spring this year caused ticks to emerge ahead of schedule. But has the early start led to a bumper crop of the bloodsucking parasites this year?

Not in Minnesota, says Elizabeth Schiffman, an epidemiologist with the state Department of Health who specializes in tick and mosquito-transmitted diseases.

"With that early spring and warm weather that came early and stayed, we definitely had ticks out earlier than we have in previous years," she said. "What we didn't necessarily see is a lot more ticks. Here in Minnesota, we saw what we expected."

Some scientists in the northeastern part of the country were predicting a tick population boom this spring, based on a higher number of white-footed mice last year — a favorite host for ticks.

Typically, late spring (mid-May through early July) is the time of year when the risk of contracting tick-borne diseases is highest in Minnesota and elsewhere. But as we enter deep summer and the weather becomes hotter and drier, the threat of infection tends to lower.

"Once we get to this time of year, the conditions are less favorable for ticks to be out and about questing," Schiffman said. "Their activity will be down in the next couple months."

But adult ticks once again will be out in full force in September and October.

With tick-borne diseases such as Lyme disease and the dreaded Powassan encephalitis on the rise, here's a primer on how to avoid infection:

First, understand that there are hundreds of species of ticks, and not all of them can make you sick.

Stay clear of the black-legged tick, also known as the deer tick. It can transmit the pathogens that cause Lyme disease, an illness that affects 300,000 people a year in the United States and can cause serious complications if not detected and treated early, according to the Centers for Disease Control and Prevention. Common symptoms include fever, joint aches and headache. A rash in the shape of a bull's-eye may also appear.

Generally, the tick must be attached for at least 36 to 48 hours to infect a human with the bacterium that causes Lyme disease, the CDC says. Other diseases transmitted by the black-legged tick include human anaplasmosis and babesiosis.

The black-legged tick is much smaller than the wood tick, or dog tick, as it's sometimes called. Black legged ticks live in wooded areas mostly and need humidity to survive, according to the Minnesota Department of Health. They most often are found along the edges of trails in the woods and they generally attach to a person or animal near ground level. They don't jump, and they can't fly.

Tips to avoid tick bites include:

• Keep lawns mowed and brush trimmed.

• Walk in the middle of trails.

• Use bug repellent with DEET.

• Wear long sleeves and long pants tucked into socks.

• Promply check for ticks after spending time outdoors.