The arthritis can last from a few days to a few months, but if the Lyme infection goes untreated the arthritis may become a chronic problem.

Despite gains made in understanding the disease, experts remain ignorant about many facets of the natural course that Lyme infection takes in the body.

The abundance of hosts and tick vectors would favor the establishment of Lyme infection in Africa.

He added that if someone has an active Lyme infection, "They should probably wait until the infection is over before they receive the vaccine."

Though it may seem illogical, a test should also not be ordered if the patient has the telltale rash that often signals Lyme infection, the researchers said.

The tests, he said, are accurate in more than 90 percent of cases of long-term Lyme infection.

In the human trials of both vaccines, after two injections, most recipients were protected against Lyme infection only 50 percent of the time.

A "bulls-eye" rash that often clears in the center as it spreads outward is the hallmark of a Lyme infection.

The chronic arthritis rarely develops if antibiotics are prescribed in the first six weeks after Lyme infection develops.

Diagnosis Problems To be sure, extreme incapacitating effects of a Lyme infection are rare.