HACKENSACK, N. J. — The tick — that perennial nemesis of outdoor lovers — is back again, and physicians for both humans and their pets are counseling caution against the Lyme disease it carries.

Tick habitats include brush and woodland, where they attach themselves to the ubiquitous field and forest mice and deer. Deer ticks, also known as black-legged ticks, are the smaller species and transmit Lyme disease. Wood ticks, also known as dog ticks, are prevalent as well.

A big problem is that ticks are active year-round and don’t even go into hibernation unless ground temperatures are below 35 degrees Fahrenheit.

The primary host of Lyme disease is the mouse. Ticks that become infected from feeding on the blood of mice can then pass the disease on to humans or animals. Field mice feed on acorns, and so are more common in oak forests.

However, state Department of Health spokeswoman Dawn Thomas noted, “If you are in any forest, regardless of type of tree, you should wear a repellent, long sleeves/socks, and/or do a tick check on your body afterward. We don’t have any evidence there is a greater risk in an oak forest.”

If bitten, seek medical advice, experts say. Symptoms of Lyme disease include a bull’s-eye rash, flulike symptoms and extreme fatigue. If detected early, the disease can be treated successfully with antibiotics.

If left untreated, it can lead to serious heart and nervous system problems. Other long-term effects include headaches, chronic stomach problems, memory loss, stiffness of joints and speech impairment.

Katie Reynolds of Lafayette, N. J., along with her husband, Roy, who was diagnosed with Lyme disease in June 2007, has organized a Lyme disease support group in the hope of raising awareness about the debilitating illness.

“It’s really sad to see how this disease has affected my husband and robbed him of a life,” Reynolds said. “That’s my biggest struggle.”

Although there is no specific cure, Reynolds said educating oneself and keeping a positive attitude on a day-to-day basis is the best way to mentally equip a person suffering from the disease and help them on the road to recovery. “Be your own advocate and trust in your doctor,” Reynolds said.

With once-wooded farmlands developing into residential areas, an increase in tick cases can be seen in suburban communities.

Regarding prevention, health authorities offer the yearly reminder: Avoid potential infestation areas—including woodlands, wooded edges near homes and landscaped areas with dense ground cover; use insect repellent; wear solid, light-colored clothing — on which the dark-colored tick will stand out — with pants tucked into socks so ticks can’t infiltrate. People also should examine themselves, along with their children and pets, for ticks frequently.

As for pets, said veterinarian Carole Jones, the best way to protect them against infection is to check them for ticks every day and use a tick collar or topical solutions.

But, she added, “Even with all the products out there, none of them are 100 percent, so pet owners have to remember to do their part, especially if they have been outside and have been hiking with their dogs.”