Fleas not so harmless!
Fleas have a preferential host, a mammal or a bird, but Ctenophalus felis
and canis may attack humans!
The flea, 1/32
to 2/16
inches long (0·8 to 6 mm), is an insect the body
of which is compressed laterally, with a tough carapace furnished
with stiff hairs. It has no wings, and its three long pairs of legs
allow it to skip 16" (40 cm) away.
It is a hematophagus1, too, the mouth organs
of which allow the insect to sting and comprise one
upper lip and two long mandibles which delimit a canal through which
blood is sucked.
Its bite causes an intense pruritus2 with
an erythematous area, a red spot around the place of the
bite. Thus, germs may penetrate into the blood and cause
tularemia3. Dipylidium
caninum, the tapeworm conveyed by the dog-flea,
causes provoque nausea, vomiting, nervous troubles and
a loss in weight.
If the home is visited by fleas and rats which leave dejections,
we now face various rickettsioses such as typhus
fever, which is caused by Rickettsia mooseri: high fever,
cutaneous eruption, a tuphos, or state of stupor
and indifference take place in the sick person.
Plague
Bubonic plague4 is conveyed when the rat flea
is infected by the Yersin bacillus:
a high fever, vomiting and diffuse pains appear suddenly. At the point of inoculation,
a red hyperthophied ganglion or plague bubo evolves towards fatal
septicaemia5 or towards suppuration and recovery.
Pulmonary plague, conveyed by the saliva of a sick person,
is expressed through a sensation of distressing asphyxia
and abundant expectoration, rich in Yersin bacilli, and therefore very contagious.
The prognosis is fatal.
Fleas lay large eggs from which are issued vermiform blind larvae
which spin a silk cocoon.
Anoplura not known well enough
This is the Pediculus, a parasite of numerous animals, three species
of which are bound to humans: Pediculus humanus
capitis, Pediculus humanus corporis and Phthirus pubis.
We know them fairly well, since they are the lice, wingless insects
with a flat, long, soft body,
1/64
to 1/4 inches long
(0·4 to 6 mm), covered with hairs. They are hematophagus
insects, too, and they have mouth stylets adapted to
perforating the skin and sucking blood. They cling with the grippers
made by an internal projection of their tibias
and a think, curved claw.
Their bite conveys numerous infectious diseases. Louse borreliosis is due to
a lack of hygiene and
is transmitted by squeezing a louse on the skin. The incubation takes a week.
A high fever appears, with a general uneasiness
and then a hepatic attack and meningeal problems. On the sixth day, all these symptoms
disappear. A new attack begins one week
later. Ocular complications may appear.
Les poux
Pediculus humanus capitis, or head louse causes a pediculosis
of the scalp, together with pruritus and
scratching lesions which get over-infected.
Pediculus humanus corporis, or body louse, is small, with legs
ending with a hook; it moves very quickly and
nestles in the folds of the skin, the hairs, and clothes.
It may live one month if the temperature is 22 °C.
It is responsible for a pruritus, particularly at night, with scratching
lesions, exanthematic typhus fever which
begins after two weeks' incubation, with important shivering, a high fever,
headache, articular and other pains.
After 4 to 5 days, there appears a red eruption,
or exanthema6 and tuphos. The temperature
stabilises. The eruption becomes general and its colour turns to dark red.
Without a treatment, serious complications with
myocarditis and coma are responsible for a large number
of deaths.
The female lays about ten eggs every day. The eggs, or nits clutch to
the hairs and hair of the host, or on
textile fiber. The young ones suck the host's blood immediately after hatching.
Contagion may be made by the simple contact with bedclothes, clothes, headrests,
cinema seats, and so on.
|
In the beginning of the 21st century,
the conditions of hygiene are still the origin of numerous diseases
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Part 1 : Such trivial tiny beasts • [Première Partie : Ces bestioles si banales]