Characteristics of Arthropoda ● Metamerism- ● Metamerism- body is segmented. ● Exoskeleton- ● Exoskeleton- body covered with a hard external skeleton. ● Bilateral Symmetry- ● Bilateral Symmetry- body can be divided into two identical halves.
Characteristics of Arthropoda Jointed Appendages- Jointed Appendages- each segment may have one pair of appendages, such as: ● ● legs ● ● wings ● ● mouthparts
Characteristics of Arthropoda ● Open Circulatory System- ● Open Circulatory System- blood washes over organs and is not entirely closed by blood vessels. Our system is a closed one ● Ventral Nerve Cord- ● Ventral Nerve Cord- one nerve cord, similar to our spinal column
Some of the arthropods are ectoparasite. Ectoparasite: arthropod living outside the human body Some Common Ectoparasites ● Common bedbugs (Cimex lectularius) ● Human fleas (Pulex irritans
Classes of Medical Importance Subphylum CRUSTACEAE Two Class are medically important ● Arachnida ● Class Arachnida ● Insecta ● Class Insecta
Class insecta D i p t e r a Nematosera ( mosquitoes, black flies) Brachisera (flies) Anoplura (Lice) Cins Pediculus Phthirus Phthirus Heteroptera (Bugs) Cins Cins Cimex Oeciacus Triatoma Triatoma Rhodnius Rhodnius Panstrongylus Panstrongylus Cins AnophelesCulex Aedes SimuliumPhlebotomus Lutzomyia Cins Musca, Glossina, Calliphora, Cochliomyia,Cordylobia, Lucilia, Sarcophaga Wohlfahrtia,Gasterophilus Hypoderma,Cuterebra Siphonaptera (Fleas) Cins Pulex Ctenocephalides Ceratophyllus Archaeopsylla Xenopsylla Tunga ------------------------------------------------------------------------------------------------
Class insecta ● ● The insects are the most numerous and diverse of all the groups of arthropods. There are more species of insects than species in all the other classes of animals combined.
Class insecta ● ● Insects differ from other arthropods in having three pairs of legs. In size, insects range from less than 1 mm to 20 cm in length, the majority being less than 2.5 cm long.
Characteristics of Insecta 1- 1- 3 body segments- head, thorax, abdomen (stomach area). 2- One pair of antennae 3- Tracheal Respiratory System- composed of tubes, with holes (spiracles) through the body that admit air. ●. ● So, they do not have lungs at all.
Characteristics of Insecta 4- 4- Wings- usually two pairs of wings, although some have one pair of wings, or none. No other class of arthropods has wings 5- 5- 3 pair of legs, 1pair to each of the 3 thoracic segments. Compound eyes, with facets
Order Diptera (Flies) The larvae of flies. The larvae of flies. Flies are common in the warmer months, and love dead, stinky, and rotting material. They lay eggs, and the eggs develop into larvae (maggot) that need to eat. They appear quite fast (8-12 hours), and will eat away tissue if the conditions are present Flies are common in the warmer months, and love dead, stinky, and rotting material. They lay eggs, and the eggs develop into larvae (maggot) that need to eat. They appear quite fast (8-12 hours), and will eat away tissue if the conditions are present
Myasis Disease that results from the infestation of tissues or cavities of the body by larvae(maggots) of flies
Anopheles ● mosquito (Culicidae). ● Anopheles is a genus of mosquito (Culicidae). ● Plasmodium ● There are approximately 460 recognised species: while over 100 can transmit human malaria, only 30-40 commonly transmit parasites of the genus Plasmodium that cause malaria which affects humans in endemic areas. ● Anopheles gambiae –Plasmodium falciparum. ● Anopheles gambiae is one of the best known, because of its predominant role in the transmission of the deadly species –Plasmodium falciparum.
Wuchereria bancrofti ● Some species of Anopheles also can serve as the vectors for Filariidae Wuchereria bancrofti ● (Aedes,Culex) ● Mosquitoes in other genera (Aedes,Culex) can also serve as vectors of disease agents. Anopheles gambiae
Culex Cx. Pipiens Adults of the Cx. Pipiens complex complex are light brown mosquitoes that lack distinctive markings on the proboscis and legs, and are not readily separated from other Culex (Culex) mosquitoes. Adult females of the complex are usually identified by the presence of distinctive, basal, pale abdominal bands.
Phlebotomus (sand flies) Phlebotomus (sand flies) The female sand fly carries the Leishmania protozoa from infected animals after feeding, thus transmitting the disease, while the male feeds on plant nectar. Phlebotomus species are also vector for phlebotomus fever, arbovirus phlebotomus fever, an arbovirus caused by Toscana virus.
Adults are small sized about 1.5-3 mm, yellowish Adults are small sized about 1.5-3 mm, yellowish in colour with in colour with conspicuous black eyes,hairy body, wings and legs. conspicuous black eyes,hairy body, wings and legs.
Anoplura (Lice) Pediculus ● Pediculus humanus capitis ● Pediculus humanus corporis Phthirus ● Phthirus pubis
Lice Morphology ● Wingless insects. ● Permanent ectoparasite. ● Host specific parasites,each lice species is found on only a single species of host.
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 (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 (Bugs) Order Heteroptera (Bugs) Cimex Cimex lectularius ● They are about 3–4mm long ● Dorsoventrally flattened bodies ● Greatly reduced wings ● A bloodsucking proboscis that can be folded back ventrally
Siphonaptera -Fleas Pulex Pulex Pulex irritans (Pulex) Pulex irritans (Pulex) This flea is about 2–5mm long, ● Laterally flattened, ● Wingless ● Have three pairs of legs, the hindmost of which are highly adapted for jumping.
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)
Class Arachnida Ticks (Ixodida). ● They are blood-sucking, opportunistic parasites that can attach to the skin of a variety of vertebrate hosts. ● They have no segmentation and are dorso-ventrally flat with four pairs of legs
Ixodes ricinus ● Vector of the causative agents of Lyme borreliosis and Tickborne encephalitis ● Human tick bites in central Europe are in most cases caused by I. ricinus and only occasionally by other tick species.
DISEASES FOR WHICH HARD TICKS ARE CARRIERS BACTERIAL DISEASES BACTERIAL DISEASES ** Rocky Mountain Spotted Fever The causative agent,Ricketsia rickettsii, ** Tularemia The causative agentFrancisella tularensis The causative agent,Francisella tularensis **Q Fever ** Q Fever The causative agent, Coxiella burnetii
DISEASES FOR WHICH HARD TICKS ARE CARRIERS BACTERIAL DISEASES **Human erlichiosis The causative agent, bacteria of the Ehrlichia family. **Lyme Dısease The causative agent (USA) The causative agent Borrelia burgdorferi (USA) Borrelia garinii or Borrelia afzelii ( In Europe )
DISEASES FOR WHICH HARD TICKS ARE CARRIERS VIRAL DISEASES ** Crimean-Congo Hemorrhagic Fever The causative agent Nairovirus. ** Tıck -Born Encephalitis The causative agent,Tick-borne encephalitis virus
Mites Sarcoptes scabiei Causative agent of scabies Scabies mite (Sarcoptes scabei) is the cause of scabies and is distributed worldwide. Epidemics of the disease may occur for long periods but mites may be common at all times in very poor communities with inadequate washing facilities.
Sarcoptes scabiei Transmission is by close contact (sexual partners, family,members, school children, healthcare staff) from person to person, Indirect transmission on clothes (underclothes), bed linens is not a primary route, but should be considered as a factor in control measures. Without a host, mites usually die off within a few days. Mite infections can also be acquired from animals to which humans have close skin contact.