EntomologyEntomology

MosquitoesMosquitoes Have worldwide distribution Have worldwide distribution

Morphology:Morphology:4-10 mm in size.4-10 mm in size.

Head: carries a pair of eye, a pair of long antennae Head: carries a pair of eye, a pair of long antennae and a mouth.and a mouth.

In female: the mouth parts are adapted for piercing In female: the mouth parts are adapted for piercing and sucking of blood.and sucking of blood.

In male: the mouth parts are not well developed, it In male: the mouth parts are not well developed, it feeds only plant juice.feeds only plant juice.

Thorax: It is three segmented. It carries three pairs of Thorax: It is three segmented. It carries three pairs of legs and one pair of wings covered by scales.legs and one pair of wings covered by scales.

Abdomen: Slender and long, it is made up of eight Abdomen: Slender and long, it is made up of eight segments.segments.

Life cycleLife cycle: Female mosquitoes lay eggs on water, : Female mosquitoes lay eggs on water, which hatch releasing larvae, which then which hatch releasing larvae, which then converted to pupa, then within two days, adults converted to pupa, then within two days, adults are formed and fly out of the water.are formed and fly out of the water.

Adults ----- eggs ------ larva ----- pupa ------ adultAdults ----- eggs ------ larva ----- pupa ------ adult

Acquatic stages of mosquitoes (living in water):Acquatic stages of mosquitoes (living in water):

1- larva 2- pupa1- larva 2- pupa

MosquitoesMosquitoesThe commonest mosquitoes are: The commonest mosquitoes are:

1- Anopheles: Spotted wings (dark and pale 1- Anopheles: Spotted wings (dark and pale spots of scales).spots of scales).

2- Culex: Unspotted wings and unspotted legs.2- Culex: Unspotted wings and unspotted legs.

3- Aedes: spotted legs3- Aedes: spotted legs

Medical importance of Mosquitoes:Medical importance of Mosquitoes:

1- They act as vectors for human diseases1- They act as vectors for human diseases

a- Anopheles:a- Anopheles:

1- Malaria: 1- Malaria:

infective stage: sporozoitesinfective stage: sporozoites

Mode of transmission: bite of female anopheles, by Mode of transmission: bite of female anopheles, by which it injects the sporozoites into blood of man.which it injects the sporozoites into blood of man.

2- Filaria: (ex. Wuchereria bancrofti)2- Filaria: (ex. Wuchereria bancrofti)

Infective stage: infective larvaeInfective stage: infective larvae

Mode of infection: bite of female mosquito by which it Mode of infection: bite of female mosquito by which it deposits the infective larva on human skin and the deposits the infective larva on human skin and the larva enter through the wound bitelarva enter through the wound bite

3- Arboviruses:3- Arboviruses:

Infective stage: virusInfective stage: virus

Mode of transmission: bite of female mosquito Mode of transmission: bite of female mosquito injecting the virus with its saliva.injecting the virus with its saliva.

B- Culex:B- Culex:

1- Arboviruses (similar to anopheles)1- Arboviruses (similar to anopheles)

2- Filaria (similar to anopheles)2- Filaria (similar to anopheles)

C- Aedes:C- Aedes:

1- Yellow fever:1- Yellow fever:

Infective stage: virusInfective stage: virus

Mode of transmission: bite of female aedes mosquitoMode of transmission: bite of female aedes mosquito

2- Dengue fever:2- Dengue fever:

Infective stage: virusInfective stage: virus

Mode of transmission: bite of female aedes mosquitoMode of transmission: bite of female aedes mosquito

3- Filaria: (similar to anopheles)3- Filaria: (similar to anopheles)

4- Bacterial diseases:4- Bacterial diseases:

Infective stage: TreponemaInfective stage: Treponema

Mode of transmission: bite of female aedes mosquitoMode of transmission: bite of female aedes mosquito

2- Diseases produced by mosquitoes:2- Diseases produced by mosquitoes:

All types of mosquitoes produce dermatitis at the site All types of mosquitoes produce dermatitis at the site of bite.of bite.

Adult anopheles: (spotted wings)Adult anopheles: (spotted wings)

We have to differentiate between male and We have to differentiate between male and female. Differentiation occurs by the mouth female. Differentiation occurs by the mouth partpart

- Male:Male: dense hair. Maxillary palps are as dense hair. Maxillary palps are as long as the proboscis, with clubbing.long as the proboscis, with clubbing.

- Female:Female: less hair. Maxillary palps are as less hair. Maxillary palps are as long as the proboscis, but they are slender long as the proboscis, but they are slender with no clubbing.with no clubbing.

Adult culex: (unspotted wings nor legs)Adult culex: (unspotted wings nor legs)

We have to differentiate between male and We have to differentiate between male and female. Differentiation occurs by the mouth female. Differentiation occurs by the mouth partpart

- Male:Male: dense hair. Maxillary palps are as dense hair. Maxillary palps are as long as the proboscis, they are slender.long as the proboscis, they are slender.

- Female:Female: less hair. Maxillary palps are less hair. Maxillary palps are shorter than the proboscis. shorter than the proboscis.

Larva of anopheles and culex: Larva of anopheles and culex:

Larva consists of head, thoracic and abdominal Larva consists of head, thoracic and abdominal segments.segments.

- Culex:Culex: The 8 The 8thth abdominal segment carries a abdominal segment carries a respiratory siphon.respiratory siphon.

- Anopheles:Anopheles: No respiratory siphon. No respiratory siphon.

Control of mosquitoesControl of mosquitoes 1- Protection of man from bites of mosquitoes by:1- Protection of man from bites of mosquitoes by:

- Sleeping under netsSleeping under nets- Wearing protective clothesWearing protective clothes- Using repellentsUsing repellents- Living away from water collections.Living away from water collections.

2- Destruction of mosquitoes by:2- Destruction of mosquitoes by:

- Physical methodsPhysical methods: drainage of any water : drainage of any water collection on filling with sandcollection on filling with sand

Control of mosquitoesControl of mosquitoes

- Chemical methodsChemical methods: Application of substances in : Application of substances in

water that are toxic to the acquatic stages, as water that are toxic to the acquatic stages, as paris green and petroleum oils.paris green and petroleum oils.

- Biological methodsBiological methods: Application of living : Application of living organisms in water to eat the larva. Ex. gambusia organisms in water to eat the larva. Ex. gambusia fish eats the larvae.fish eats the larvae.

3- Control of adult mosquitoes:3- Control of adult mosquitoes: By spraying insecticidesBy spraying insecticides

Sand flies (phlebotomus)Sand flies (phlebotomus)Females are blood suckers, while males feed on Females are blood suckers, while males feed on

plant juices. plant juices.

Morphology:Morphology:1.5 – 2.5 mm in size, yellowish in colour.1.5 – 2.5 mm in size, yellowish in colour.

Head, thorax and abdomen. Hairy, the hairs cover the Head, thorax and abdomen. Hairy, the hairs cover the body, wings and legs.body, wings and legs.

Has humped thorax, attached to it one pair of wings Has humped thorax, attached to it one pair of wings and 3 pairs of legs.and 3 pairs of legs.

Male has claspers on the posterior end.Male has claspers on the posterior end.

Medical importance of Phlebotomus:Medical importance of Phlebotomus:

1- They act as vectors for human diseases1- They act as vectors for human diseases

1- Leishmania: 1- Leishmania:

infective stage: promastigotesinfective stage: promastigotes

Mode of transmission: bite of phlebotomus.Mode of transmission: bite of phlebotomus.

2- Phlebotomus fever:2- Phlebotomus fever:

Infective stage: virusInfective stage: virus

Mode of transmission: bite of phlebotomus.Mode of transmission: bite of phlebotomus.

3- Oroya fever (bartonellosis): 3- Oroya fever (bartonellosis):

Infective stage: BartonellaInfective stage: Bartonella

Mode of transmission: bite of phlebotomus.Mode of transmission: bite of phlebotomus.

2- Diseases produced by phlebotomus:2- Diseases produced by phlebotomus:

They produce dermatitis at the site of bite.They produce dermatitis at the site of bite.

Life cycle:Life cycle:Female phlebotomus lays eggs in cracksFemale phlebotomus lays eggs in cracks

Adult ---- eggs ----- larva ---- pupa ----- adultAdult ---- eggs ----- larva ---- pupa ----- adult

Control of sand fly:Control of sand fly:Sand flies have tendency to stay close to the ground Sand flies have tendency to stay close to the ground

and of short flight range. So, they are easily and of short flight range. So, they are easily controlled.controlled.

The control is by:The control is by:

1- Insecticides1- Insecticides

2- Filling of cracks.2- Filling of cracks.

3- Sleeping under nets3- Sleeping under nets

4- Application of repellants.4- Application of repellants.

Musca (house fly)Musca (house fly)World wide in distribution. World wide in distribution.

Morphology:Morphology:Medium- sized flies, 6 – 9 mm in length.Medium- sized flies, 6 – 9 mm in length.

Head: contains 2 compound eyes and 3 simple eyes, Head: contains 2 compound eyes and 3 simple eyes, 2 antennae and sucking mouth part.2 antennae and sucking mouth part.

Thorax: carries 3 pairs of legs and one pair of wings.Thorax: carries 3 pairs of legs and one pair of wings.

Abdomen: 4 segments.Abdomen: 4 segments.

Life cycle:Life cycle:Female musca lays its eggs on garbages.Female musca lays its eggs on garbages.

Adult ----- eggs ---- larva ---- pupa ---- adultAdult ----- eggs ---- larva ---- pupa ---- adult

Medical importance of musca:Medical importance of musca:

– Medical transmission of organisms on legs and Medical transmission of organisms on legs and

body hairs:body hairs:

1- 1- Parasitic diseases:Parasitic diseases: Cyst of Entamoeba histolytica, Cyst of Entamoeba histolytica, cyst of Giardia, eggs of Ascaris.cyst of Giardia, eggs of Ascaris.

2- 2- Bacterial diseases:Bacterial diseases: Typhoid, Cholera. Typhoid, Cholera.

3- 3- Viral diseases:Viral diseases: Poliomyelitis, Hepatitis. Poliomyelitis, Hepatitis.

Control of musca:Control of musca:

A- Control of adult flies:A- Control of adult flies:- Wire screening of housesWire screening of houses- Fly net over the foodFly net over the food- Insecticides.Insecticides.

B- Control of breeding places:B- Control of breeding places:- Garbage should be properly disposedGarbage should be properly disposed- Sanitary disposal of excretaSanitary disposal of excreta- Health education.Health education.