Grass crawler is the common name, often referred to as ticks, after the bite of the local easy to appear pimples, redness, swelling or vesicles, and in serious cases there will be fever, muscle pain, weakness and other symptoms. Need to go to the hospital dermatology or infectious disease department in time for treatment. Ticks are generally more common from May to June, mainly found in the grass, forests, but also can be parasitized on pets. Tick bites are characterized by localized pimples, redness, swelling or erosion, accompanied by varying degrees of itching or pain. After a bite, the tick usually buries its head under the skin, making it difficult to remove. In addition, ticks can carry a variety of viruses, which can cause viral infections and different symptoms of disease after biting. Some ticks carry Borrelia burgdorferi, the causative agent of Lyme disease, which can cause an epidemic after a bite. Infection results in a wandering erythema of the skin, which is followed by joint pain, elevated temperature, headache, arthritis, and generalized malaise. Some ticks carry Neobunyavirus, which can infect peripheral blood neutrophils after bite, causing fever with leukopenia, thrombocytopenia and multiple organ damage. Fever, general malaise, muscle pain, nausea, diarrhea, mental depression and other symptoms usually appear, and severe cases can be life-threatening. The first thing to do after being bitten by a tick is to wrap the tick in paraffin oil or petroleum jelly so that the tick is deprived of oxygen and pulls its mouthparts out and away from the skin by itself. It is recommended to visit a dermatologist or infectious disease department promptly after being bitten by a tick, and to treat the tick with medication under the guidance of a doctor.