Christiana Borough, PA

Nymphs are questing, the highest-risk stage for people. Nymphal deer ticks peak in late spring and summer. They're the size of a poppy seed, easy to miss, and cause most Lyme transmission.

Christiana Borough is 73% natural land cover (49% forest, plus open and brushy areas) across its 0.53 sq mi, home to about 1,099 people. That makes it the 13th-most wooded of the 60 towns in Lancaster County. Deer ticks live in wooded areas, along trail edges, and in tall grass — the more of that a town has, the more places ticks can quest.

Lancaster County reports about 80 Lyme cases per 100,000 people a year, the 158th-highest of 210 Northeast counties. That county-level disease pressure, combined with Christiana Borough's local habitat, sets how high its daily score can climb when the weather and season allow.

Yes. Nymphs are questing, the highest-risk stage for people. In Christiana Borough, today's risk reads moderate (38/100). Ticks are active. Use repellent, stick to trails, and do a tick check when you come inside.