The public is being warned to take precautions against ticks as the wet and mild summer has caused a peak in numbers of the blood-sucking parasite.
It follows a big rise in cases of Lyme Disease in Hampshire, Dorset and Berks.
The highly infectious disease is transmitted through tick bites and can lead to blindness, paralysis and even death if left undiagnosed.
Visitors to the countryside are urged to wear trousers, use insect repellent and check their skin for ticks.
According to the Health Protection Agency, most cases of Lyme Disease occur between late summer and early winter, believing tick numbers have risen because of the mild winter of 2006, followed by a long wet, humid period.
The disease is caused by the bacterium Borrelia burgdorferi.
Borreliosis and Associated Diseases Awareness UK (BADA-UK) said it had increased by 90% since 2006 across the UK, and the New Forest, the South Downs, Dorset and Berkshire have been named as tick hot-spots.
The most common symptom is a slowly expanding rash that spreads out from a tick bite, usually after about five to 14 days.
Typical symptoms also include fever, headache, fatigue, and a characteristic skin rash called erythema migrans.
But it can be hard to spot because of the variety of symptoms, and can easily be mistaken for something else.
Most cases of Lyme disease can be treated successfully with a few weeks of antibiotics, but if left untreated, infection can spread to joints, the heart, and the nervous system.
Removal of the tick within 24 hours also helps to stop the transmission of bacteria.