Sand fleas are most prominent in the early mornings and evenings when the temperature is slightly cooler. To prevent sand flea bites, head to the beach in the middle of the day. You may still get a few bites, but there will not be as many fleas out during this time. You should also avoid the beach when it is raining. Sand fleas are most active in cool and moist temperatures. Insect repellent may help to prevent sand fleas from biting. Prior to heading to the beach spray insect repellent on your feet, ankles, and legs. Follow the directions provided and look for a repellent that specifically mentions sand fleas. You may also want to have the repellent with you at the beach so that you can re-apply after swimming! A great way to prevent sand flea bites is by covering your legs, feet, and ankles. Sand fleas can only jump 20 to 40 cm (8-16 inches) so it is unlikely that you will get bit anywhere above the waist. While walking along the beach, wear light pants and sandals. If you are lying down on the sand, make sure to sit on a towel or blanket.

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Write a summary of the previous text in Vietnamese:
Tránh ra bãi biển vào lúc bình minh hoặc hoàng hôn. Thử dùng sản phẩm xua đuổi côn trùng. Che kín chân, bàn chân và mắt cá.