ABSTRACT
Larvae of mites in the family Trombiculidae, sometimes called chiggers (Figure 18.1a), harvest mites, or red bugs, are medically important pests around the world, primarily because they cause dermatitis and may transmit the agent of scrub typhus. Adult chiggers are oval shaped (approximately 1 mm long) with a bright red, velvety appearance, but it is only the larval stage that attacks vertebrate hosts. Chigger larvae are very tiny (0.2 mm long), round mites with numerous setae (Figure 18.2). The mites may be red, yellow, or orange in color and have a single dorsal plate (scutum) bearing two sensillae and four to six setae. Identification to the species level is extremely difficult and expert technical help is required (see Chapter 8).
