寄生虫学课件Arthropods(节肢动物) 1(2015 双语)

Direct injury
Annoyance and sucking blood Damage by toxic substances
biting / contact / active projection / ingestion Example： Paederus fuscipus: dermatitis Allergic reaction (anaphylaxis) allergen: saliva, secretory and excretory substances Example: dust mites (allergic rhinitis and asthma) Invading tissues Example: Myiasis, scabies，Tungiasis，
quinone tanned protein Open circulatory system: the body cavity is
hemocoel, full of haemolymph Molting or ecdysis and Metamorphosis (变态)
Ⅲ Arthropods of medical importance
the largest phylum, account for 75% of all animals
I Introduction
Medical arthropods
Arthropods with medical imபைடு நூலகம்ortance:
parasitic arthropods, or vectors of pathogens
Medical arthropods 医学节肢动物
Assoc Prof. Dr. Lei Jiahui Department of Human Parasitology
Teaching points
• Morphology of arthropods • Classification of medical arthopods • Harmful effects on human • Criteria to judge medical arthropod • Mosquitoes and flies
1 pair of antennae Example: diplopod
Ⅳ Harmful effects on human
1. Direct injury 2. Indirect injury: diseases transmission
Arbo-disease: diseases transmitted by medical arthropods • Mechanical transmission:
Ⅱ Morphology of arthropods
Bilaterial symmetry, Segmentation of body and
appendages (antennae, palps and legs) Exoskeleton (外骨骼) : consists of chitin and
1 Class Insecta (昆虫纲) 3 parts (head, thorax and abdomen), 3 pairs of legs, 1 pair of antennae (触角) Example: mosquito, fly, flea, louse, etc
2 Class Arachnida (蛛形纲) 2 parts (cephalo-thorax and abdomen) or as a combined body，4 pairs of legs, no antennae Example: tick, mite, spider, etc
4 Class Chilopoda (唇足纲) slender, flat and segmented body, 1 pair of antennae Example: Centipede
5 Class Diplopoda (倍足纲) long pipe-shaped and multi-segmented body,
Examples of mechanical transmission
Insects
Pathogens
Diseases
house fly, cockroach Salmonella spp Salmonellosis
house fly
comma bacillus (霍乱弧菌）
cholera
house fly, cockroach E. histolytica
not multiply or develop in the arthropod not an integral part of the life cycle of the pathogen
• Biological transmission:
either multiples, develops, or both in the vector. one part of the life cycle of the pathogen
Medical arthropodology (entomology) a subject to study :
morphology, classification, life cycle, ecology, geographical distribution, pathogenesis, regularity of disease transmission and control strategies
Ⅲ Arthropods of medical importance
3 Class Crustacea (甲壳纲) cephalothorax and abdomen, 2 pairs of antennae, 5 pairs of walking legs, most live in water Example: shrimp, crab, cyclops，etc