Mosquito, Adult Feeding on the Skin

There are many different species of mosquito, some of which carry some of the worlds most common and most economically important infectious diseases. Malaria and yellow fever are two of the most important diseases they carry. Others include encephalitis (viral), dengue fever, and leishmaniasis. (Courtesy of the Centers for Disease Control.)

Mosquito, Adult

This illustration shows an adult southern house mosquito. This mosquito feeds on blood and is the carrier of many diseases, such as dengue fever, yellow fever, and others. (Courtesy of the Centers for Disease Control.)

Mosquito, Egg Raft

Mosquitoes of the Culex species lay their eggs in the form of egg rafts that float in still or stagnant water. The mosquito lays the eggs one at a time sticking them together in the shape of a raft. An egg raft can contain from 100 to 400 eggs. The eggs go through larval and pupal stages and feed on micro-organisms before developing into flying mosquitoes. (Courtesy of the Centers for Disease Control.)

Mosquito, Pupa

These are mosquito pupa. This is another stage in the development of the mosquito. (Courtesy of the Centers for Disease Control.)

Meninges of the Brain

The organs of the central nervous system (brain and spinal cord) are covered by 3 connective tissue layers collectively called the meninges. Consisting of the pia mater (closest to the CNS structures), the arachnoid and the dura mater (farthest from the CNS), the meninges also support blood vessels and contain cerebrospinal fluid. These are the structures involved in meningitis, an inflammation of the meninges, which, if severe, may become encephalitis, an inflammation of the brain.