- Frelons and mosquitoes are known to spoil our meals and summer nights, but their period of activity can be extended in autumn, even to the beginnings of winter. This is also the case of ticks that remain active at the end of summer, warns the Auvergne-Rhône-Alpes ARS. - Frelons, ticks, mosquitoes... why we need to redouble our vigilance at the end of summer (Health and well-being).