MANOJ KUMAR (SHELFORD)

Showing posts with label anopheles. Show all posts
Showing posts with label anopheles. Show all posts

Tuesday, February 18, 2014

VECTOR OF MALARIA (A GENERALIZED STUDY)




VECTOR OF MALARIA
 download pdf format
Malaria or chill and fever disease is an old age human disease and is still prevailing. This disease is prevalent in all countries extending from 40South to 60 North, but the tropical zone is endemic home of al types of malaria. Malaria is caused by intracellular protozoal endoparasite belonging to genus Plasmodium. Four species of Plasmodium are responsible for causing malaria in human – P. vivax, P. Falciparum, P. malariae and P. ovale.
BIOLOGY OF VECTOR OF MALARIA
Out of about 45 species of Anopheles found in India, only few have been identified as malarial vector. They are Anopheles culicifacies, A. fluviatilis, A. minimum, A. philippinensis, A. stephensni, A. sundaicus and A. leucosphyrus.
DISTRIBUTION
They are cosmopolitan in distribution. The area of distribution of Anopheles varies with species. A. philippinensis are found in plains, A. sundaicus and A. stephensi are found in coastal regions, while A. fluviatilis inhabits the foot hill regions. Out of above mentioned species of Anopheles, A. fluviatilis is highly anthrophilic i.e. have high preference for human blood and thus are the most important vector of malaria in man.
HABITS AND HABITAT
Mosquitos are nocturnal, troublesome and irritating insect. They inhabit near human population. Only female Anopheles sucks the blood which is required for oviposition. Male Anopheles is short lived and lives on nectars of flowers and plant juices. Anopheles are known to hibernate in adult form when conditions are unfavourable. Normally they do not fly far away from their breeding grounds. But instances have been reported of Anopheles having flying range of 11 km. the life span of female Anopheles is 8-34 days, as it is on the stake of environmental conditions.
GENERAL CHARACTERS
Anopheles mosquito are thin bodied with long delicate legs, making an angle of 45 with ground while resting. Body divisible into head thorax and abdomen.
Head lies at anteriour extremity ob body, bears a pair of large compound eyes, long palpi, a pair of antennae, long proboscis (piercing and sucking type). Male lacks the biting apparatus. The antennae in males is of bushy type (plumose) while the antennae in males is less bushy as compared to that of male.
Thorax is round and bears a pair of spotted wings and three pairs of long delicate legs, the beating of wings produce the notorious buzzing sound.
Abdomen is long, narrow and made up of ten segments, the last two segments are modified as external genitalia.
LIFE HISTORY
There are four stages – Egg, Larva, Pupa and Adult. Breeding period extends throughout the year. Copulation occurs during flying. Female lays about 80-100 eggs in early hours of morning in relatively clean and stagnant water. Each egg is boat shaped bearing lateral floats. The ganotrophic cycle (period between taking blood and laying eggs) is upto 48 hrs. egg hatches into larva within 2-3 days.
DIFFERENT STAGES OF LIFE CYCLE OF ANOPHELES MOSQUITO

Larva or wriggler  is a free swimming stage. The body is divisible into head, thorax and abdomen, head bears compound eyes, antennae, and simple eye each in pairs. Thorax is segmented while abdomen is nine segmented. In 8th segment is present respiratory siphon, and in 9th segment four respiratory gills are present. The larva are bottom feeders. And their body lies parallel to water surface. Larval period last up to 5 – 7 days.
Pupa is coma (,) shaped, active but non feeding stage. Body divisible into cephalothorax and abdomen. A pair of small respiratory trumpets are present on the cephalothorax. 9th abdominal segment bears a pair of paddles and each paddle bears pair of bristles. Within 7 days imago or adult mosquito emerges out from pupa.

MODE OF INFECTION
Plasmodium is digenetic (requires two hosts to complete its life cycle – man and female Anopheles). Man is the secondary host in which Plasmodium spends it asexual phase of life while female Anopheles is the definite host in which it undergoes its sexual cycle.
When a female Anopheles bites a malaria infected person, the micro and macrogametocytes from the patient enters the Anopheles’s gut, where after performing sexual reproduction zygote is formed. The motile zygote penetrates out of the gut wall to be changed into cystic stage (oocyte), inside the oocyte by the process of sporogony sporozoites are formed and thus the parasite acquires its infective stage (sporozoite). The whole process take upto 8-10 days. Such infected mosquito when bites a healthy person, the sprorzoite stage of the parasite is transmitted to the new host through the salivary secretion of the mosquito. So mosquitos belonging to the genus Anopheles are the vector of malaria.
CONTROL
The best way to control malaria is keeping the population of its vector under control, which is the primary weapon to control malarial infection. Use of excessive insecticides has led to appearance of resistant varieties of mosquito, and also environmental degradation.
1.     ANTILARVAL MEASURES: not allowing water to accumulate in places, proper drainage system and filling  and levelling of ditches.
2.     CHEMICAL CONTROL: it includes A) application of kerosene, diesel, fuel oil, etc in stagnant water in a week.
3.     Application of paris green (Copper acetoarsenite) in mosquito breeding places. It leads to stomach poisoning of larva leading to death.
4.     BIOLOGICAL CONTROL: introduction of larvicidal fishes such as Gambusia and Lebistes, in breeding places is helpful.
5.     ANTI-ADULT MEASURES: killing of adult mosquitoes by applying various insecticides.

6.     PROTECTION AGAINST MOSQUITO BITES: use of mosquito nets, repellents etc.

 download pdf format

Blog Archive

Labels

2012 4TH LARVAL AND PUPAL STAGES. manoj kumar adaptations ADHATODA VASICA agarose agarose gel electrophoresis. agaros gel electrophoresis theory allergic reactions allergy amino acids anopheles ANSWER KEYS CSIR antheraea mylitta ANTI-HEMOLYTIC anti-typhoid antibacterial antibody anurans aquatic aquatic mammals arthropoda autotrophs BACTERIAL DISEASES BAT BEHAVIOUR benedict reagent benedict's reagent benedict's test benedicts reagent biochemistry bioscan biotechnology BIRDS bis bizzare phenomena blood blood sucking blood sucking bugs bruce effect bugs carbohydrate carbon dioxide CARNIVORUS. CAT CBSE CBSE 2014 CBSE EXAM CBSE SEMESTER II SCIENCE cbsex census 2011 centepede central board of secondary education chapter chapter 2 chapter2 class class 6 CLASS 7 class x class6 CLASS7 classical genetics CLASSIFICATION classification of amino acids cloning vectors COMMON DISEASES conference india CSIR WEB LINKS cuscuta dav dempster department of zoology Digestive System DNA RECOMBINANT TECHNOLOGY DOG domestic domestic levels. india DOWNLOAD NET ANSWER KEYS DOWNLOAD NET QUESTION PAPERS drury haemocytes drury hemocytes ecology ecoscan electrophoresis elements of innate immune system energy entomology environmental biology. exam extraction farmers fat father female anopheles fertilisers fine structure of antibody FMD food food chain FOOT AND MOUTH DISEASE Franz frog vocal FUNCTIONS fut content analysis GE02 gel genetic engineering genetics giardia giardiasis glucose test gorakhpur conference 2013 gram stain harmony - 2013 harmony 2-13 HARMONY 2014 harmony-2013 harmony2013 hemiptera heteroptera heterotrophs house centipede hypersensitivity immune system immunology in in plants India inheritance innate inportance INSECT ENDOCRINOLOGY isotypes Jhakrhand kwashiorkor lamblia larval stage law of minimum leibig levels limiting factors M. P. SINHA M. P. SINHA. malaria malarial malnutrition mammals mammals. manoj kumar manoj kumar shelford manoj kumar zoology manoj kumar zoology ranchi marasmus MATING microbiology MINERAL CONTENTS minerals MODE OF ACTION OF RABIES VIRUSE molecular genetics Mp sinha national environmentalists association ncert nea NEA CONFERENCE nea conference 2013 NEST nutrition nutrition in NUTRITIVE VALUE origin and evolution of reptiles oxygen parasite PARENTAL CARE IN BIRDS pcr pharmacological photosynthesis physical barriers PHYTOCHEMICALS PLACENTA PLACENTA VERA plants plasmids plasmodium polyadenylation. polymerase chain reaction potable potable water precipitaion test pregnancy block proper growth protein protein energy malnutrition proteins PROTOZOAN DISEASE purification qpcr qualitative test RABIES RANCHI UNIVERSITY RANCHI. revesion test RHEOCIRUSE SA -b 1SCIENCE SA CBSE SCIENCE SA-II SCIENCE SAMPLE PAPER CLASS X saprotrophs science SCIENCE CBSE science class x Scoliodon Scoliodong ppt scutigera sex linked inheritance shelford significance of foood chain soxhlet soxhlet extraction soxhlet. soxlet extraction stanley cohen STUDIES ON ANTHERAEA MYLITTA DRURY HEMOCYTES DURING 3RD sucking sucking bugs Sukumar Dandapat summative assesment summative assesment - II summative assesment 2012 synce ten trap cropping TYPES TYPHOID UDAIPUR UMBILICAL CORD use of radioactive isotopes vectors VIRUS. VIRUSE vitamins VITEX NEGUNDO vocalisation in amphibia vocalization in amphibians Von water web