Phylum Arthropoda - PowerPoint by p58FD8



  Doç.Dr.Hrisi BAHAR
     Phylum Arthropoda
   Subphylum CRUSTACEAE

         ●Class Arachnida

       ●Class Insecta
                                    Class insecta

         Diptera                       Anoplura          Heteroptera       Siphonaptera
                                                            (Bugs)            (Fleas)
                                             (Lice)                             Cins
   Nematosera                                 Cins           Cins               Pulex
(mosquitoes, black flies)
                                             Pediculus      Cimex
  Cins         Brachisera                                   Oeciacus       Ctenocephalides
Anopheles         (flies)                                                    Ceratophyllus
Culex                Cins                                                    Archaeopsylla
Aedes                                                       Rhodnius           Xenopsylla
             Musca, Glossina,
Simulium                                                   Panstrongylus        Tunga
Phlebotomus     Calliphora,
Lutzomyia   Cochliomyia,Cordylobia,
             Lucilia, Sarcophaga

 ● Pediculus humanus capitis
● Pediculus humanus corporis

      ● Phthirus pubis
● Wingless insects.
● Permanent ectoparasite.
● Host specific
  parasites,each lice
  species is found on only
  a single species of host.

●Incomplete metamorphosis (egg-nymph-adult)
●Spend their entire life on the host
● Two species of lice infest humans, one of
 which is divided into two subspecies.

● Lice are dorsoventrally flattened insects,
 about 1.5–4mm in length, wingless, with
 reduced eyes .
●The head has short (five-segmented)
 antennae, piercing and sucking mouthparts,
 and strong claws designed to cling to hairs.

● Lice develop from eggs (called nits) glued to
● The hatched louse grows and molts through
   three nymphal stages to become an adult.
● Lice remain on a host permanently; both
   males and females are hematophagous and
   require frequent blood meals.
Life cycle of lice
                  ●   Life cycle
                       1st instar nimf
                      2nd instar nymph
                      3rd instar nymph

           ● All stages are found on
                   host body

          ● Can not survive out of the

● Among the various species of lice only the body
  louse is a vector of human diseases.

  It transmits
  -Typhus fever (caused by Rickettsia prowazekii)
  -Relapsing fever (caused by Borrelia recurrentis)
  -Trench fever (caused by Bartonella quintana).
  -Tularemi (caused by Pasteurella tularensis)
     Pediculus humanus capitis
           (Head louse)

● To day in our region the medical importance
  of lice is not due to their vector function, but
  rather to the direct damage caused by their
● Oval body, length 2.2–4.0mm, morphology
  very similar to the body louse.
● Nits are 0.5–0.8mm long.The nits are glued
  to the base of the hair near the skin.
     Pediculus humanus capitis
           (Head louse)

●Duration of development from nit to adult is
 17 days.
● The lifespan of adults on human host is
 about one month, survival off host at room
 temperature is for up to one week.
              Pediculus humanus capitis
                    (Head louse)

● Occurs worldwide; epidemic-like outbreaks of head
  louse infestation are observed regularly, especially in
  schools and kindergartens, homes, groups of

● Transmission is in most cases by personal contact
  (mother-child contacts,children playing, etc.), but can
  also be mediated by such objects as combs,caps,
  pillows, head supports, stuffed animals, etc.
     Pediculus humanus capitis
           (Head louse)

 Clinical manifestation
● Pruritus and exforiations in the scalp area,
 nits on hairs,especially in the retroauricular
 area,scalp dermatitis, especially at the
  nuchal hair line: small papules, moist
 exanthema, and crusting are
  exemples of clinical manifestation.
       Pediculus humanus capitis
             (Head louse)

● It can be diagnosed   by the determination
 of symptoms and detection (direct or with
 magnifier) of lice and/or nits, especially
 around the temples,ears, and neck
            Pediculus humanus capitis
                  (Head louse)

● In group outbreaks, all contact persons must
 be treated concurrently,e.g., entire school
 classes and the families of infested children.
● Rinsing the hair with 5% vinegar in water
 followed by mechanical removal of the nits
 with a “louse comb” is a supportive measure.
            Pediculus humanus capitis
                  (Head louse)

● Because eggs hatch 6–9 days after oviposition, if a
  pediculicide is used, treatment is recommended to be
  repeated at least once and this after 10 days, when
  all lice have hatched from the eggs, a third treatment
  on day 5 is recommended.
● Patients were treated by chimicals,natural
  products,enzyme based products,combs,hot air,
  silicone-based lotions
          Pediculus humanus corporis

● Oval body, length: 2.7–4.7mm.
  Very difficult to distinguish from head louse

● Localization mainly in clothing, where nits
   are deposited on fibers. These lice contact to
   the host only for blood meals.
     Pediculus humanus corporis

● Duration of life cycle is about three weeks.
  lifespan on host usually is four to five weeks
  rarely as long as two months.

● Bite reactions on the body, especially
  around the underwear, are indicative of body
  louse infestation. diagnosis is made after
  inspecting clothing for nits and lice.
     Phthirus pubis     (Crab or Pubic Louse)

● Infestations are more frequent in adults than
 in children and in men more frequently than

● This louse species can be readily
 differentiated from the head or body louse:
 small, length 1.3–1.6mm,with trapezoid or
 crablike body form
    Phthirus pubis (Crab or Pubic Louse)

● The parasites are most often found on hair
  of the pubic and perianal region, more rarely
  on hairy areas of the abdominal region, hairs
  around the nipples, beard hairs, eyelashes,

●The life cycle takes three to four weeks.
 crab lice die at room temperature within
 two days.
       Phthirus pubis (Crab or Pubic Louse)

●   Transmission of crab lice is almost solely by
    way of close body contact (sexual
    intercourse in adults or parent-child contact).

●   Indirect transmission on commonly used
    beds, clothes, etc. is possible, but is
    not a major factor.
              Phthirus pubis
           (Crab or Pubic Louse)
● Pruritus and scratches in the genital area and
  other infestation sites . In some patients typical
  slate-blue spots, a few mm to 1cm in size can be
  observed as a clinical manifestations

● It can be diagnosed by detection of lice and nits in
  the pubic area and other possible localizations.
        Pediculus humanus

● Pediculus humanus capitis(head louse)
localization and sites of oviposition
 Hair on the head, rarely on beard hairs or hairy sites
  on upper body.

● Pediculus humanus corporis(body louse)
 localization and sites of oviposition
Stitching, seams, and folds in clothes, especially where
it is in direct contact with the body.
               Phthirus pubis

● Phthirus pubis (crab louse)
localization and sites of oviposition
Hair of pubic area, more rarely in the
abdominal and axillar regions, beard,
eyebrows, and eyelashes.
Order Heteroptera

  Cimex lectularius
               Cimex lectularius

The bedbug, occurs worldwide.

● They  are about 3–4mm long
● Dorsoventrally flattened
● Greatly reduced wings
● A bloodsucking proboscis that
  can be folded back ventrally
         Life cycle
           ● Egg
          ● Larva
         First stage larva
        Second stage larva
         Third stage larva
         Forth stage larva
         Fifth stage larva

           ● Adult
 Development from the egg
through five larval stages to
the adults takes about one
and a half months under
suitable conditions, but can
be extended to as long as
one year.
           Cimex lectularius

● Bedbugs require several blood meals during
 development and egg production.

● Their ability to starve for as long as a year
 means they can persist for long periods in rooms,
 hiding by day (under mattresses, behind
 furniture,in cracks in the walls, etc.) and
 emerging at night questing for a blood meal.
                 Cimex lectularius

● The bedbug      is therefore often not considered
When diagnosing skin lesions. Bedbugs live on human
blood.Especially in repeated infestations, their bites
induce hemorrhagic or urticarial-papulous reactions,
often visible as lesions arranged in groups or rows.

● Diagnosis is based on skin lesions and detection of
bugs in the vicinity. Therapy is symptomatic.
            Pulex irritans (Pulex)
            Xenopsilla Cheopis (Xenopsilla)
Ctenocephalides canis/Ctenocephalides felis
          Tunga penetrans (Tunga)
           Pulex irritans

● This flea is about 2–5mm long,
● Laterally flattened,
● Wingless
● Have three pairs of legs, the hindmost of which
  are highly adapted for jumping.
                Pulex irritans

● The mouthparts form a
beaklike proboscis for

● The antennae are short.

● Combs of spines (ctenidia)
 can adorn the head and
 first thoracic segment
             Pulex irritans

● Fleas are ectoparasites in humans and
vertebrate animal species.

● Frequent blood meals are needed during the
one to three month egg-laying period

● Most of the eggs fall off the host and
continue to develop in cracks and crevices.
    ● The life cycle of an
    adult flea varies from
    few weeks to one year.

                Life Cycle

               Pulex irritans
● The fleas in this group are periodic

● The adult stages remain for the most part
  on the host while the larva and pupa live in
  the vicinity of their hosts in the so-called
 “nest habitat.”
              Pulex irritans
● In certain regions, fleas serve as vectors for
  viruses, bacteria,rickettsiae, protozoa,and

● Fleas are best known as the vectors of the
  causative agent of “plague”,Yersinia pestis
  (rodent-infesting fleas of the genus
               Pulex irritans
 In the clinical manifestations,dermal
 reactions to fleabites go through several

1-Early reaction: within five to 30 minutes
 after the bite, a dotlike hemorrhage (at the
 site of the bite) and a reddening (erythema)
 with or without a central blister are formed,
 accompanied by pruritus.
              Pulex irritans

2-Late reaction: after 12–24 hours, itching
 papules form, surrounded by erythemas up
 to palm-size, some with a central blister or
 purulent pustule; this
 reaction persists for one to two weeks
               Pulex irritans

● Sites for lesions are extremities, neck, nape
  of neck,shoulders,less often the trunk.
  Reactions are usually in multiple groups,

● A diagnosis is given based on the skin
  lesions and the case history
                     Pulex irritans
symptoms of plague

Skin reaction after flea bite   Skin symptoms of plague
             Tunga penetrans

● Fleas of the Family Tungidae
Tunga penetrans is causative agent of
tungaosis (tungiasis)

● Infest humans and animal species.

● They live in sandy soil.
            Tunga penetrans

● They penetrate the skin head first, then
  swell up within one to two weeks,
  sometimes reaching the size of a pea, from
  their original size of 1–2mm in length.

● They lay eggs over a period of about two
weeks, and then die while still under the skin.
             Tunga penetrans

● Clinical lesions are mainly on the soles of the
feet and between the toes, more rarely
on other parts of the body.
● Lesions are reddened, pea-sized, painful
nodules with a craterlike central depression.
Inflammatory and sometimes purulent
infiltration of the lesions can be seen
             Tunga penetrans

● The diagnosis is based on the characteristic
  skin lesions and can be confirmed by
  parasitological or histological examination of
  the material removed from the sores.
           Tunga penetrans

● Treatment consists of mechanical removal
  of the female flea under local anesthesia
  and control of the secondary infection.
● Topical application of ivermectin is also
● Prevention demands that shoes that fit and
  close properly be worn.
Fleas are competent vectors for numerous
      microbial pathogens of medical
        and veterinary importance

     ● Ctenocephalides felis (Cat flea)
                     Vector of
     -Cat scratch disease (Bartonella species)
          -Spotted fever (Rickettsia felis)
             -Plague (Yersinia pestis)

       ● Xenopsilla Cheopis(Rat flea)
                    Vector of
             -Plague (Yersinia pestis)

        ● Pulex irritans(human flea)
                    Vector of
             -Plague (Yersinia pestis)

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