A walk in the Sussex countryside could be a health hazard, experts have warned.

The Health Protection Agency (HPA) has said that tick bites, which can transmit Lyme disease, are more common at this time of year.

The insects are found in most parts of the South Downs, forests and heathland areas around Sussex and the rest of the south east.

There are around 800 confirmed cases of Lyme disease in the UK each year but the actual number is believed to be closer to 3,000 as some people suffer only mild symptoms and do not see a doctor.

The majority of Lyme disease cases reported in the UK is acquired here rather than overseas, often through recreational activities including walking, trekking and mountain-biking.

A spokesman for the HPA in Sussex said: “Ticks are very small and can easily be overlooked, so it is important to check regularly.

“Most ticks do not carry the infection.

“If one is found it should be removed promptly, as infected ticks are unlikely to transmit the organism if they are removed in the early stages of attachment.

Lyme disease is a bacterial infection and early symptoms develop between three to 32 days after receiving a bite from an infected tick.

The first sign is often a pink or red rash around the bite site.

The rash can gradually spread to form a large circle up to 50cm in diameter.

Other problems include flu-like symptoms such as headaches, chills, tiredness, muscle pains, joint aches and fever.

More serious complications may develop weeks or months after an infected bite is untreated, including temporary facial paralysis, pain, weakness or loss of sensation in the arms, legs or trunk and arthritis.