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K.A.ABINAYAPRE-FINAL YEAR
EPIDEMIOLOGIC INTERACTIONS
AGENT FACTORS MALARIA IS CAUSED BY 4 DIFF SPECIES OF PLASMODIUM GEOGRAPHIC DISTRIBUTION OF PLASMODIA
IN INDIA:
P.MALARIAE-KARNATAKAP.OVALE:TROPICAL AFRICA,VIETNAM
INFECTION % PLASMODIUM SPECIES
70% P.VIVAX
25-30% P.FALCIPARUM
4-8% MIXED
LESS THAN 1% P.MALARIAE
LIFE HISTORY OF MALARIAL PARASITE
ANIMAL RESERVOIRHUMAN RESERVOIRCHILDREN AS RESERVOIRS
CONDITIONS TO SERVE AS A RESEROVIR:
BOTH SEXES OF GAMETOCYTES IN BLOODGAMETOCYTES MUST BE MATUREGAMETOCYTES MUST BE VIABLEPRESENT IN SUFFICIENT DENSITY-AT
LEAST 12 /cu.mm OF BLOOD
AS LONG AS MATURE, VIABLE GAMETOCYTES IN BLOOD
GAMETOCYTES IN SUFFICIENT DENSITY
VIVAX INFECTION:4-5 DAYS
FALCIPARUM INFECTION :10-12 DAYS
RELAPSES:
•VIVAX AND OVALE MALARIA•3 YRS AFTER FIRST ATTACK•ORIGINAL SPOROZOITE INDUCED LIVER SCHIZONTS
RECURRENCES:• FALCIPARUM AND P.MALARIAE• CHRONIC BLOOD INFECTION • ERYTHROCYTIC SCHIZOGONY LOW LEVEL PERSISTENCE
AGE:*ALL AGES*NEW BORNS-CONSIDERABLE RESISTANCE
SEX:MALES
RACE:SICKLE CELL TRAIT
DUFFY NEGATIVE
PREGNANCY:IUD OF FETUS,PRE MATURE LABOR,ABORTION
SOCIO ECONOMIC DEVELOPMENT:DIS APPEARED IN DEVELOPED NATIONS
HOUSING:ILL VENTILATED AND ILL LIGHTED HOUSESSITE,TYPE OF CONSTRUCTION,NATURE OF WALLS-CONTROL PLANNING
POPULATION MOBILITY:INTERNAL MIGRATION
OCCUPATION:
HUMAN HABITS:SLEEPING OUTDOORS,REFUSAL TO SPRAYING,NOMADISM
IMMUNITY:• AQUIRED AFTER REPEATED EXPOSURE• IN ENDEMIC AREAS:• INFANTS BORN:• SPECIES SPECIFIC:• SEMI-IMMUNE INDIVIDUALS:
SEASONAL DISEASE:JULY TO NOVTEMPERATURE:
OPTIMAL TEMP:20-30 DEGREES CIF TEMP BELOW 16 DEGREES CTEMP >30 DEGREES C-LETHAL
HUMIDITY:RELATIVE HUMIDITY 60%
RAIN FALL:• INCREASES ATMOSPHERIC HUMIDITY• HEAVY RAIN- ADVERSE EFFECT• PARODOXICALLY, IN SRI LANKA-EPIDEMIC AFTER DROUGHTALTITUDE: NOT FOUND ABOVE 2000-2500 MMAN-MADE MALARIA:BURROW PITS,GARDEN POOLS, IRRIGATION CHANNELS etc
FEW INTERSTING FACTS ON ANOPHELES:
HOW DOES A MOSQUITO BITE???(DOES IT BITE?!!?)
WHY DOES A MOSQUITO NEED HUMAN BLOOD?
WHEN DOES ANOPHELES BITE MAN?
HOW FAR DO THE MOSQUITOES FLY?
HOW LONG DO THEY LIVE?
WHERE DO THEY HIDE?
WHERE DO THEY LAY EGGS?
•A. (A.) sacharovi•A. (C.) aconitus•A. (C.) annularis•A.(C.) culicifacies•A. (C.) fluviatilis•A. (C.) jeyporiensis•A. (C.) minimus•A. (C.) philippinensis•A. (C.) pulcherrimus•A. (C.) stephensi malariaspecies.html•A. (C.) sundaicus•A. (C.) superpictus•A. (C.) tessellatus•A. (C.) varuna
FACTORS DETERMINING VECTORIAL IMPORTANCEDENSITY
CRITICAL DENSITYAN.CULICIFACIES-HIGH DENSITYAN.FLUVIATILIS-LOW DENSITY
LIFE SPANVECTOR-SHOULD LIVE ATLEAST 10 TO 12 DAYS AFTER AN
INFECTIVE BLOOD MEAL.STRATEGY IN ERADICATION
CHOICE OF HOSTANTHROPOPHILICZOOPHILIC
RESTING HABITENDOPHILYEXOPHILY
BREEDING HABITSMOVING WATER-AN.FLUVIATILISBRACKISH WATER-AN. SUNDAICUSSTAGNANT WATER-AN.STEPHENSI
TIME OF BITING
VECTORIAL CAPACITYDENSITY OF THE VECTOR POPULATIONSUSCEPTIBILITY TO INFECTIONLIFE SPANPROBABILITY OF FEEDING ON MAN
RESISTANCE TO INSECTICIDES
VECTOR
DIRECT
CONGENITAL
VECTOR TRANSMISSIONCERTAIN SPECIES OF INFECTED FEMALE AN. MOSQUITOES
DIRECT TRANSMISSIONACCIDENTALLY BY I.M. OR I.V.
PARASITES SURVIVE ATLEAST 14 DAYS IN BLOOD STORED AT -4°C
PERSONS WHO HAVE LIVED IN AN ENDEMIC AREA AND
THOSE WHO HAD MALARIA SHOULD NOT BE ACCEPTED AS BLOOD DONORS UNTIL 3 YEARS
CONGENITAL TRANSMISSION