False hookworm

Ternidens deminuus, an intestinal nematode of monkeys in the Old World tropics and recorded from humans in Southern Africa and Mauritius. One of the nodular worms.

False negative

A negative test result for a condition that is, in fact, present.

False positive

A positive test result for a condition that is not, in fact, present.

Family

A taxonomic group of similar, related, animals. The taxonomic group that is below Order, but above Genus.

Fasciola hepatica

The common liver fluke. In tropical regions this species is replaced by F. gigantica. Like all trematodes, their intermediate hosts are aquatic snails. Infection occurs when the infective metacercariae are ingested on vegetation in swampy areas. Normal final (definitive) hosts are sheep, cattle and various wild animal species. Humans can acquire fascioliasis if they eat contamiated water cress etc.

Fasciolopsis buski

The intestinal fluke. Definitive hosts are pigs and humans. Metacercariae encyst on aquatic plants such as water chestnuts in south east Asia.

Feeding habits

Habits determining the times and places of feeding and the sources of blood meals for mosquitoes.

Fievre Boutonneuse

Wide-spread spotted fever. Tick-borne and caused by Rickettsia conori.

Filariasis

A parasitic infection caused by filarial nematode worms, such as Wuchereria bancrofti and Brugia malayi, causing a variety of illnesses. See also elephantiasis and onchocerciasis.

Filariform

A long, slender, simple and muscular structure as in Strongyloidea.

Fire coral

The colloquial name for Millepora.

Fire jelly

See Morbakka.

Fire weed

The colloquial term for Lytocarpus philippinus.

Flinders Island Spotted Fever

A tick-borne disease found on Flinders Island, north of Tasmania. Zoonotic and caused by Rickettsia honei.

Fluke

Generally refers to helminth in the Class Trematoda or trematodes.

Fly

A two winged insect of the Order Diptera. Includes the housefly and the myiasis- causing flies. Also includes the mosquitoes and the tsetse flies.

Focus

The origin or source of an infection or vector population.

Fugu

The term applied to mild puffer fish poisoning causing mild paresthesiae around the lips after eating fish prepared by a special cook. Accidental overdose may, and does, cause human fatality in Japan.

Fungus

Eucaryotic (nucleated) organisms, reproducing by means of spores and have no chlorophyll, e.g. mushrooms, toadstools, moulds.