
Q. Can you describe the life cycle of deer ticks in Virginia?
A. The life cycle of the deer tick, also known as the blacklegged tick, or Ixodes scapularis, is generally two to three years. During this time, they go through four life stages: egg, larva, nymph and adult. After the egg hatches, the larva and then nymph must find a blood meal to develop to the next life stage.
Larval and nymphal ticks can become infected with Lyme disease bacteria when feeding on an infected wildlife host, which is usually a rodent. Nymphs or adult females can then spread the bacteria during their next blood meal.
Deer are important sources of blood for ticks and are important to tick survival and movement to new areas. However, deer are not infected with Lyme disease bacteria and do not infect ticks.
Q. Do deer ticks transmit Lyme disease with a single bite?
A. In most cases, a tick must be attached for 36 to 48 hours or more before the Lyme disease bacterium can be transmitted. If you remove a tick quickly (within 24 hours), individuals can greatly reduce the chances of getting Lyme disease. In areas of the Eastern United States where Lyme disease cases are common, people may be bitten by deer ticks carrying bacteria from spring through the fall. From April through July, nymphs are actively looking for hosts in the environment, and in early spring and fall seasons, adults are most active.
Nymphal ticks pose a particularly high risk due to their abundance and small size – about the size of a poppy seed – which makes them difficult to spot. Lyme disease patients are often not even aware of a tick bite before getting sick. Adult female ticks also can transmit the bacteria, but because of their larger size – about the size of sesame seed – they are more likely to be noticed and removed from people before transmission of the bacteria can occur.
Q. Has the deer population in Virginia grown or lessened, and how is that affecting deer ticks this season?
A. Beginning in the 1940s, work was done to protect Virginia’s deer herd and it subsequently grew as a result of protective game laws, deer stocking and habitat restoration. Today, deer management objectives have changed to control and stabilize populations over much of Virginia.
Current computer reconstruction models provide a pre-hunt season population estimate of 850,000 to 1 million deer in Virginia. According to the Virginia Department of Wildlife Resources, most of Virginia’s deer herds are managed through regulated hunting at moderate to low population densities, in fair to good physical condition, and below the biological carrying capacity of the habitat.