All of 8 villages of Lam Thuy and Ngan Thuy communes are high malaria endemic areas. The slide positive rates (SPR) in Lam Thuy and Ngan Thuy are 11.56% and 36.20% respectively; P. falciparum positive rates are 72.50% and 67.80%; Parasite positive rates in children at 1-5 years old are 45.00% and 32.20%. Habit of sleeping without bed net of the local population and unfectioning microscopic points have made the malaria situation higher in these two communes. Anopheline component in Km 14 village, Ngan Thuy commune, Le Thuy district is abundant (19 species): with the presentation of the two main malaria vectors An.dirus and An.minimus. The landscape in this area is suitable for the production and development of two main malaria vectors as well as other anopheline mosquitoes
Malaria ; mosquitoes ; diagnosis ; Anopheles

Mosquitoes and larvae were investigated in the forests, edges of forest and other landscapes in the jungles of U Minh Thuong and U Minh Ha during two years of 2002 and 2003. A total of 15 species (24.19% of total mosquitoes species found throughout the country and 37.5% of those in the Southern Vietnam) was found, some of which were typical species of the water forest fauma. A mingle species composition of flood plain forest fauna with presence of An. paraliae, An. umbrosus, An. separatus... and coastal brackish fauma with An. sundaucus and An. nimpe found in the study sites suggests that the forests narrowness, forest fires and other ecological damages have caused the changes of species composition and distribution of mosquitoes of forest fauna
Anopheles ; epidemiology ; Larva ; Trees

Experiments were carried out on free mating An. minimus strain in the laboratory. Under condition of illumination power at 200-220 lux the rates of larvae developed to pupae and to adults were 62.7% and 59.3%, respectively. The mean life span of the males was shorter than that of females. At optimum rearing density of one mosquito per 1.3 cm2 of a vertical side of holding cage the inseminated rate was 72% and mean number of eggs was 145 per female. The size of 30 x 30 x 30 cm of holding cages and illumination power at 200 lux seemed to be suitable for efficient mating of An. minimus
Anopheles ; mosquitoes ; malaria

An.Sundaucus collected from Can Gio, Ho Chi Minh City are colonized at the insectary of the National Institute of Malariology, Parasitology and Entomology and found to quickly adapt to the laboratory conditions. Since the F3, larvae have been living in the artificial brackish water with NaCl 1%. In this condition, 88% of larvae developed to pupae and 83.5% to adults. Light time 10 hours per day with 250 - 270 lux was determined to be conducive for development of larvae
Anopheles ; malaria ; Larva ; Adult

A research was conducted in 2001 and 2002 to evaluate the efficacy of remaining spray by using Permethrin 50EC to kill both kinds of vectors: Xenopsylla cheopis and Anopheles minimus, responsible for plague and malaria transmission, respectively. The results showed that Permethrin 50EC at the concentration of 0.5g/m2 was highly effective to kill Xenopsylla cheopis and Anopheles minimus and remained effective for 4 months
Anopheles ; Permethrin ; Culicidae

Experiments were caried out on An.minimus F98 in laboratory conditions of 22+/- 1°C, 25+/- 1°C and 28 +/- 1°C, 70-80% RH. The time required for egg stage and egg hatching rate were negatively correlated with temperature. At 22 +/- 1°C, egg hatching rate was 84.1 %, the duration of the egg stage was 3-4 days. At 25+/-1°C and 28 +/-1oC, egg hatching rate was 77.3% and 65.5%, respectively, the time of the egg stage were 2-3 days. At higher temperature, the duration of larvae stage was shorter than at the lower temperature. 25°C was optimum temperature for larvae with 38% of larvae developed to adults. 1 day after molting, mosquitoes started feeding at all tested temperatures. At 22°C, blood feeding rate higher than at the higher temperatures. Number of eggs and egg hatching rate of mosquitoes that fed human blood were higher than mosquitoes fed on mice
Anopheles ; Temperature ; Blood ; Laboratories

Anopheles dirus mosquitoes collected in the field of Khanh Phu commune, Khanh Vinh district, Khanh Hoa province were reared in the insectarium. The typical karyotype (2n=6) have 2 pairs of chromosomes and one pair of sex chromosomes. The chromosome III are the longest and submetacentric and the II are shorter and metacentric. The sex chromosome is heteromorphic. Three types of X (Xl; X2; X3) chromosomes and 2 types of Y (Yl; Y2) chromosomes were identified. The study on biological characteristics shows that An. dirus are anthropophilous has interest in human blood but they can feed on mice. Mosquitoes fed by human blood were found to lay more eggs (45 - 258 eggs) that those fed on white mice (15 - 148 eggs). The appropriate water level for the advanced development of larval stage should be 10mm to 20mm. Mass death of larvae was observed while protozoa intensively developed in the rearing aquarium.
Anopheles ; Epidemiology ; Diagnosis

The eggs of Anopheles dirus originated from China and currently colonized at the National Institute of Malariology, Parasitology and Entomology kept at 24 - 26°C on wet cotton for 20 - 25 days gave hatching rate approximately of 40%. The suitable food for Anopheles dirus larvae consisted of 6g bread powder, 2g green bean powder and 0.5mg vitamin B 1. The appropriate density for rearing An. dirus larvae is 0.4 larva per square centimetre of water surface
Malaria ; Anopheles ; Laboratories

An. minimus was collected from Hoa Son village, Luong Son district, Hoa Binh province in November 1997 and maintained in the laboratory of NIMPE by artificial mating techniques. Since 51st generation, a free mating colony in the small cages (with dimensions of 30 x 30 x 30cm) has been established by releasing 200 male and 200 female mosquitoes per cage. The releasing of additional 50 males of An. minimus to the cage has been found to stimulate the mating process in small cage
Anopheles ; Laboratories ; Mosquito Control

*Anopheles ; *DDT ; *Dieldrin ; *Malaysia