Insect Pest Factfile 19/2/03 4:16 pm Page 13

Fleas Description

Order: Siphonaptera

Characteristics: Adults 1-8mm long; brownish in colour, body laterally compressed (streamlined) and covered with backward-directed bristles; reduction or loss of eyes; piercing mouth parts; no wings, although transitory wing buds may appear in pupae of some ; muscular legs, with hind limbs adapted for jumping; metamorphosis complete with egg, larval, pupal and adult stages. 2.6mm long Species characteristics and host/habitat:

Cat Flea (Ctenocephalides felis) Adults, 2-3.25mm long; forepart of head longer than it is high; prominent pronotal and genal combs (first teeth of genal comb nearly as long as second); basal section of legs equipped with stout spines. Rabbit Flea (Spilopsyllus cuniculi) Mole Flea (Hystrichopsylla talpae) Host/habitat: especially members of Adults, 1.5-2.25mm long; pronotal and genal Adults 3.5-6mm long; genal comb of 9-12 family, also , other and man; combs, the latter with five vertically spines; pronotal comb of 42-58 spines. found particularly in host bedding. Many arranged rounded spines; basal section of Host/habitat: associated with moles; also infestations in commercial and institutional legs equipped with stout spines. found in gardens and outbuildings. premises derive from feral . Host/habitat: especially rabbits, in whom it is the main vector of the myxomatosis virus, Dog Flea (Ctenocephalides canis) but will also attack cats; the females are Distribution Adults, 2-3.25mm long; forepart of head as sedentary and attach themselves to the host, long as it is high; prominent pronotal and especially around the ears and head. Adult live exclusively as parasites of genal combs (first teeth of genal comb only warm-blooded animals, especially mammals, about half as long as second); basal section Tropical Rat Flea (Xenopsylla cheopis) although birds may also be attacked. Whilst of legs equipped with stout spines. Adults, 1.5-2.5mm long; no pronotal or they show a certain degree of host Host/habitat: especially members of genal comb; row of bristles along back of preference, fleas are by no means specific family, also domestic animals and head; basal section of legs equipped with and will feed on other animals in the man; found particularly in host bedding. stout spines. absence of the normal host. In fact they tend Host/habitat: various , but will also to be more nest than host-specific, for whilst Human Flea ( irritans) attack man; found especially around ports. the adults may feed on the blood of a variety Adults, 2-3.5mm long; no pronotal or genal of animals the larvae require more precise comb; basal section of legs equipped with Hedgehog Flea (Archaeopsyllus erinacei) conditions which are associated with the stout spines. Adults, 2-3.5mm long; genal comb of 1-3 habitats and nesting habits of the hosts rather Host/habitat: especially man, but will also short spines; pronotal comb of 2-9 spines. than the characteristics of their blood. breed on , hedgehogs, foxes and Host/habitat: generally associated with badgers; found in homes, usually in hedgehogs, but occasionally brought indoors fleas are responsible for many flea bedrooms. by dogs, cats and humans; also found in infestations, the remainder being attributable gardens and outbuildings. to a variety of bird and species. Pulex irritans infestations are now uncommon. Bird Flea (Ceratophyllus gallinae) The significance of Ctenocephalides felis is Adults 2-2.5mm long; no head folds to explained by the increased number of pets retain antennae; pronotal comb with more being kept and the tendency for their beds to than 24 teeth; no genal comb, no spines on be neglected during cleaning. Wall-to-wall basal section of legs. carpeting also provides a relatively Host/habitat: especially birds nesting in dry undisturbed environment for flea larvae to situations but will also attack animals and develop, whilst the spread of central heating man; breeding mostly limited to birds’ has served to ensure ideal temperature breeding season, migrating from the nests conditions. when fledglings leave. Often originating from birds’ nests in roof spaces.

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Significance These are distinguished by an identifiable, b) Insecticidal control usually brownish head without eyes; jaws Insecticides can be used to treat infested Fleas can be vectors of disease or may adapted for biting; three thoracic segments premises and protect them from transmit parasitic worms. The most serious and 10 abdominal segments all equipped reinfestation. In addition, hosts can be infection which they can spread is bubonic with bristles; and peg-like processes on the treated directly, or rodenticides employed. plague, transmitted to man by fleas terminal abdominal segment. The larvae (Xenopsylla cheopis) which carry the thrive in dark, humid places such as animal Host treatments: causative bacillus from infected rats. In the bedding and carpet fluff, and feed on organic Insecticidal products are available which past rodent fleas have been responsible for debris and adult flea excrement. The latter have been specifically formulated and serious epidemics of the disease, notably the forms a valuable part of the diet as a source registered for use on the host animals. Only Black Death in Europe and Asia in the 14th of blood, which some larvae, while not these products should be applied to animals to 17th centuries. Rodent fleas may also attacking the host, require for their and care should be taken to follow the carry murine typhus and, because of their development. Larvae may also be manufacturer's instructions. readiness to attack humans as well as rats, predacious, living on small and weak are probably the major flea vector of disease. . Cats’ bedding may support a flea Rodenticides: The Dog flea is an intermediate host of the population of 8000 immature and 2000 adult Where rats and mice have been identified as Dog tapeworm (), forms. A typical flea infestation may be the primary hosts in flea infestations, whose vertebrate host is usually the dog composed of adults 5%, larvae 35%, pupae rodenticides can be used to control them (occasionally the cat) but which can 10% and eggs 50%. and, indirectly, the fleas. sometimes be transmitted to man. After 2-3 weeks, by which time they will In Europe fleas are not generally responsible have moulted twice and be about 5mm long, for the transmission of disease. However, the larvae spin silken cocoons, incorporating they are still objectionable because of the debris, in which to pupate. The cocooned larvae then moult within three days to give bites they inflict and the deep-rooted social Checklist for control stigma attached to humans with flea the pupae which are initially creamy-white infestations. Occasionally psychological but change to dark brown as they mature to problems arise with the induction of become adults. This phase is the quiescent SURVEY Ð Define the extent of the delusory parasitosis, in which the victim stage and the flea may overwinter in this infestation. imagines he is infested with ectoparasites. state. The adult flea will then be stimulated Ð Identify involvement of to emerge by the vibrations set up by a animals. passing host. This explains the occasional Flea bites are identified as a tiny dark red PRE- Ð Clean thoroughly. mass attacks which take place in deserted spot surrounded by a reddened area. The bite TREATMENT Ð Remove articles from the premises. persists for one or two days and is intensely area to be treated. irritating. First bites are not generally liable Ð Treat animals, as to cause serious reactions, but they may lead The development cycle from egg to adult is appropriate. to hypersensitivity. Reactions are usually normally completed in 4 weeks but at low delayed following regular biting over a long temperatures will take much longer. TREATMENT Ð Interior. period; there will then follow a period when Ð Exterior. reactions are immediate. The cycle then Ð Control rodents etc, as repeats until a state of non-reactivity - Control appropriate. immunity - is achieved. Selecting flea control measures depends to a ADVISE Ð Expectations for control. large extent on the size of the problem. In OCCUPIER Ð Further actions by pest Life-Cycle many instances infestations of well kept control operator and houses can be easily traced to pets. Where occupier. Flea eggs are about 0.5mm long, oval, this is not the case it is useful to establish pearly-white in colour and laid indiscrimi- the pest species. This will help to identify nately in the fur or feathers of the host or in possible hosts and even the foci of the its nest or bedding. They do not adhere to infestations. Control measures must be the host but readily fall from the animal, are directed at the brood as well as the adult shaken or scratched off. The same applies to fleas. the dark coloured faeces of the adult fleas thus creating the black and white - salt and a) Hygiene/management pepper - effect associated with flea Regular cleaning will deny the their infestations. Four to eight eggs are laid after breeding site and so make an important each blood meal and a single female may contribution towards their control. Infested produce 800-1000 eggs during her lifetime, clothing, beds and bedding should be which may be as long as two years. destroyed by burning or thoroughly cleaned and the same measures employed when The eggs hatch in about one week to give dealing with old bird and animal nests. white, threadlike, legless larvae 1.5mm long. Accumulations of debris should also be Glossary of terms removed from cracks and crevices such as Genal and pronotal combs: Rows of stout the cracks between floorboards, and the spines on cheek and first thoracic segment whole area thoroughly cleaned. respectively.

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