蚤病 （ Pulicosis ）

1. 蚤病（Pulicosis） • 组员：涂春婷 谭淑娴 郑玮璐 姚俊庸 黄亦霖 07动物医学4班

2. Introduction • 犬猫蚤病是有蚤亩（ Siphonaptera ）、蚤科（Pulicidae ）、栉首蚤属（Ctenocephalides）的蚤寄生于体表所引起的犬猫疾病。寄生犬猫的蚤主要有犬栉首蚤及猫栉首蚤

3. 犬栉首蚤（Ctenoce phalides canis） 后足胫节后缘最后切刻一下，一般另有2个浅切刻，各有1或2根短状鬃；后胸背板侧区一般有3根鬃。雄性抱器柄突末端明显膨大；雌性触角窝后方一般无鬃，仅偶然有少数细鬃。寄生于犬 Morphology

4. 猫栉首蚤（C. felis） 后足胫节后缘下段只有一个浅切刻，其中有鬃1（2）根，或为一小毛代替；后胸背板侧区鬃2（1）根；雄性抱器柄末段不膨大或仅略为膨大；雌蚤触角窝背方无小鬃或小刺形鬃。

5. Both sexes of fleas are blood suckers,and only the adults are parasitic. The ovoid eggs have smooth surfaces, and may be laid on the ground or on the host from which they soon drop off. Hatching occurs in two days to two weeks, depending on the temperature of the surroundings. The larvae are maggot-like and have a coat of bristles. They have chewing mouthparts and feed on debris and on the faeces of the adult fleas, which contain blood and give the larvae a reddish colour. Under the influence of internal growth regulators, the larva moults twice, the final stage being about 5.0 mm long, and then spins a cocoon, a from of woolly pupariun, from which the adult emerges. Moulting and pupation are dependent on the ambient temperature,and though in warm conditions the whole cycle may be completed in about three weeks, in low temperatures it may extend to two years. Life cycle of flea

7. Epidemiology • 犬栉首蚤寄生于犬科动物，以及犬科以外少数食肉类动物。猫栉首蚤为广布种，具广宿主性，主要宿主有猫、犬、兔和人，亦见于多种野生食肉动物及鼠类。由于蚤活动性很强，对宿主的选择性比较广泛，因此便成为某些自然疫源性疾病和传染病的媒介及病原体的储存宿主，如腺鼠疫（glandular plague）、地方性斑疹伤寒（endemic typhus）、土拉菌病（野兔热 tularemia）等。它们也是某些绦虫的中间宿主，如犬复孔绦虫（Dipylidium caninum）、缩小膜壳绦虫（Hymenolepis diminuta）和微小膜壳绦虫（Diplacanthus nanus）等。

8. Effects on the hosts • A kitten receiving a flea bath to treat a flea infestation.A few fleas on adult dogs or cats cause little harm unless the host becomes allergic to substances in saliva. The disease that results is called flea allergy dermatitis. Small animals with large infestations can lose enough bodily fluid to fleas feeding that dehydration may result. Fleas are also responsible for disease transmission through humans. If the fleas have been sucking blood, then they will have a reddish-brown colour when squashed

9. Disease transmission • Cat fleas can transmit other parasites and infections to dogs and cats and also to humans. The most prominent of these are Bartonella, murine typhus, and apedermatitis. The tapeworm Dipylidium caninum can be transmitted when a flea is swallowed by pets or humans. In addition, cat fleas have been found to carry Borrelia burgdorferi, the etiologic agent of Lyme disease, but their ability to transmit the disease is unclear.

10. Pathogenesis • 蚤通过叮咬和分泌具有毒性及变态性产物的唾液，刺激引起犬猫强烈瘙痒的过敏反应，病猫变得不安、啃咬搔抓以减轻刺激。

11. Symptoms • 由于成蚤叮咬吸血，刺激皮肤，引起过敏反应（allergic response）。常见患畜出现痘疹、红斑和强烈的瘙痒，表现为不安，常啃咬患处。有时发生过敏性皮炎（Sensitization dermatitis），出现脱毛，落屑（desquamate），形成痂皮（crust）皮肤增厚及形成有色素沉着的皱襞，严重者出现贫血（anaemia）和衰竭（exhaustion）。

12. Lesions • 主要表现为急性散在性皮炎或慢性非特异性皮炎。在患犬和猫耳廓下、肩胛部、腰背部、下腹部、臀部、腿部和尾根等部位有红斑或痘诊出现；慢性非特异性皮炎出现在后背部或阴部。

13. Signs and symptoms • Flea infestations can be not only annoying for both dogs and humans but also very dangerous. Problems caused by fleas may range from mild to severe itching and discomfort to skin problems and infections. Anemia may also result from flea bites in extreme circumstances. Furthermore, fleas can transmit tapeworms and diseases to pets. • When fleas bite humans they may develop an itching rash（皮疹、疹子） with small bumps that may bleed. This rash is usually located on the armpit（腋窝） or fold of a joint such as the elbow, knee, or ankle（脚踝）. When the area is pressed, it turns white. • When dogs are troubled by fleas they scratch and bite themselves especially in areas such as the head, neck, and around the tail. Fleas normally concentrate in such areas. This incessant scratching and biting may cause the dog‘s skin to become red and inflamed（发炎的）. • Flea allergy dermatitis is developed by those dogs allergic to flea saliva（唾液）. In this case, the symptoms previously mentioned are more pronounced. Because of compulsive scratching and biting, the dog may lose hair, get bald spots, exhibit hot spots due to extreme irritation, and develop infections that result in smelly（发臭的） skin.

14. Diagnosis • 确诊本病须在犬猫上发现蚤。对犬猫进行仔细检查，可在被毛见发现蚤或者蚤的的碎屑，在头部、臀部和尾尖部附近的蚤往往最多。

15. Treatment and Prevention • 1.治疗（Treatment） • 杀灭犬猫的蚤，可用双甲脒（Amitraz）、伊维菌素（Ivermenctin）、除虫菊酯类、Imidacloprid等。 • 2综合性预防措施（Comprehensive prevention） • 对犬猫舍，窝巢和用具用药物喷洒灭蚤。平常应保持犬猫舍的清洁干燥和犬体卫生，做好定期消毒工作。当兽医工作者进行犬猫防疫注射和诊疗工作时，应当在鞋子、髁部、裤子外面以及袖口等处撒布鱼藤酮（Rotenone）粉以保护不受跳蚤的侵袭。 • 预防犬猫蚤病可给犬猫戴含杀虫药物的颈圈（collar）。

16. 大环内酯类杀虫剂(Macrolides insecticide)。如用伊维菌素(Ivermectin)或多拉菌素(Doramectin)进行皮下或肌肉注射。 • 甲脒杀虫剂类（Formamidine insecticide）。如用双甲脒(Amitraz) 进行药浴或涂擦。 • 有机磷类杀虫剂（Organophosphorus insecticide）。如敌百虫(Dipterex)、巴胺磷(Propetamphos)、地亚农(Diazinon)等进行药浴，涂擦或喷洒环境。 • 拟除虫菊酯类杀虫剂（Pyrethroid insectide）。如溴氰菊酯(Deltamethrin)、戊酸氰菊酯等药浴或涂擦。

17. 颈圈（collar） • Flea collars containing various insecticides（杀虫剂） are used to control fleas in both dogs and cats; the later require a special collar with a low concentration of insecticide . Care should be taken in the selection of any insecticide for dogs and cats as some preparations are licensed for use in only one host species or are used at different dose or application rates for each. • Since the greater part of the flea population is not on the animal itself, but in its environment, it is important that insecticides are also applied to its living quarters and general indoor habitat, and that bedding should be destroyed where possible. Fitted carpets should be thoroughly vacuum cleaned.