Studies on bionomics of anopheline mosquitos in Korea
Authors
황종현
Issue Date
1964
Description
의학과/박사
Abstract
[한글]
Studies on Bionomics of Anopheline Mosquitos in Korea
Whang, Chong Hyn, M.D., D.T.M.&H., D.A.P.&E.
Department of Parasitology, Yonsei University College of Medicine and
Central Malaria Eradication Service,
Ministry of Health and Social Affairs, Republic of Korea.
(Director: Professor Chin Thack Soh)
Since Korea undertook a malaria pre-eradication survey in June 1959, several
malaria endemic foci have been found in areas situated at the foot of the Taebak
Mountains which run from north to south in the eastern part of the penninsula.
Plasmodium vivax is the only species reported from those areas.
Although a few reports on anopheline mosquitos have since been published in
Korea, most of them were limited to report on the species and the seasonal
prevalence of the population of the mosquitos.
An attempt was made, in this study, to incriminate the vector of P.vivax malaria
and to elucidate the bionomics of the vector species in order to control the
anopheline mosquitos in question.
In the first part of this study, the routine entomological work was carried out
during the period of 1960-1961 in Yongju area, Kyongsang Pukdo of Korea according
to the plan of operation for the malaria pre-eradication survey in order to
incriminate the vector of malaria parasites and to elucidate the bionomics and
behaviour of the anopheline mosquitos.
During the survey, six anopheline mosquito species were recorded as follows and
are listen in approximate order of decreasing frequency. However, Anopheles lesteri
and A. lindesayi japonicus are probably the first to be recorded in Korea.
1. Anopheles sinensis Wiedmann, 1828.
2. Anopheles sineroides Yamada, 1925.
3. Anopheles koreicus koreicus Yamada and Watanabe, 1918.
4. Anopheles koreicus adwardsi Yamade, 1925.
5. Anophels lesteri Baisas and Hu, 19376.
6. Anopheles lindesayi japoniocus, Yamada, 1918.
A sinensis was the most predominant species and the next, A. sineroides, although
A, koreicus Koreicus was found to be predominant after A. sinensis in Guidandong(a
mountainous area).
Anopheline mosquitos begin to appear from late April or May and disappear in
October each year.
The resting places for the anopheline mosquitos were mainly cow sheds and
outdoors. The population density of A. sinensis is cow sheds showed a peak either
in June or July in most places with a second small peak in late August or
September.
Night biting habits appeared to be active throughout the whole night but were
more active from when it was dark after sunset to midnight.
Most of the anophelines appeared to be zoophilic, though the precipitin tests for
A. sinensis showed facultative anthropophilic.
Dissection of salivary glands of 2736 female a. sinensis resulted to prove no
sporozoites.
The body weight, moisture and fat contents in A. sinensis appeared to decreased
in July from a high peak in June and then to increase again in September.
Insecticide susceptibility tests proved that the species was susceptible to DDT
and dieldrin.
The bionomics of A. sineroides, A. koreicus koreicus, A. koreicus edwardsi, a.
lesteri, and A. lindesayi japonicus were discussed. Breeding places of A. sinensis
were mostly rice fields and streams.
In the second part, a portable wooden hut designed by the author, with two
windows in each of the four walls, fitted window traps and panels to catch
anopheline mosquitos when they entered or flied off from the hut in villages near
the tow of Yongju in Kyongsang Pukdo, one of the malaria endemic foci areas in
Korea.
During 16 night catches between 10th June and 22nd August 1963, 5120 females of
the species were caught in traps and in hut. Of them, 3223 were from entrance
traps, 1605 from exit ones and 292 in the hut.
Four night catches in the entrance traps of 110, 140, 536 and 575 of a. sinensis
and other four night catches in the exit traps of 59, 94, 179 and 55 are reported
in detail.
They revealed that mosquitos were taken virtually in the entrance traps on the
lee wards if the wind persisted from one direction, and fully fed mosquitos were
taken in the exit traps on the windwards. But when the wind direction was variable
or conditions were calm, the resembling numbers of mosquitos were found in each of
the four walls traps.
During the study, five high night catches were made, and the possible causes for
the different size of catches in some factors were discussed.
Since much of high catches in this study occured in the darkness, it would seem
that the mosouitos were attracted by the smells or odorous emanated from the host
and that their approach to the hut was not directed a visual mechanism controlling
up-wind flight.
The rain throughout the night, did not prevent flight.
the two hourly collections, made from dusk to dawn, showed a curve of activity of
A. sinensis, the greatest activity occurring between 22.00 and 24.00 hours. All the
females taken in the entrance traps were unfed except 36 specimens with a partial
fresh blood-meal and 9 gravid. First entries occurred just before a complete
darkness in the evening and the last in the good light after sunrise.
Males of A. sinensis were taken neither in the entrance traps nor the exit ones,
nor in the hut. All the females taken in exit traps and in hut had fully engorged
except 1 speciemens unfed. However, a curve of A. sinensis taken in the exit raps
which flied off from the hut into exit traps after engorged, showed a gradual
increase indicating a peak at 04.00-06.00 hour. About 15 per cent of A. sinensis
fed on baited animal remained on walls of the hut until morning . After the species
feeding on the host, they appeared to fly off to their resting places in nature
before day break. Therefore, this species would belong to Type A Senior-White's
endophagy in a pre-determined exophily according to Gillies(1956).
The parous females of A. sinensis appeared to show a tendency to fly into hut
from dusk throughout whole night, showing a peak at the period at 24.00-02.00 hour.
On judging from the Korean habits in local areas and behaviour of the species,
the sinensis would transmit P. vivax malaria to man by bit6ing outdoor.
In the third part, the investigations on mosquito hibernation and physiology were
carried out systematically in the vicinity of Seoul during the period of November
1959-April 1960 and of November 960-April 1961. Random survey was also done in
Kimhae, near Pusan in December 1959.
During the winter months, the following four species of mosquitos were found to
hibernate in the adult stage.
1. Anopheles sinensis Wiedmann, 1828
2. Anipheles sineroides Yamada, 1925
3. Culex pipiens Linnaeus, 1758
4. Culex orientalis Edwards, 1921.
These anophelines caught in cow stables were all fed, showing that they could
feed in winter. The most suitable places for the hibernation of Culex pipiens were
culverts and caves.
The anophelines appeared to be less resistant to low temperature than the
culicines.
Fat and moisture contents and body weight decreased in C. pipiens just before
their hibernation was over, and no Japanese B encephalitis virus was isolated from
the species.
The mosquitos caught in hibernating places were found to be unlliparcus and to
have sperms in the spermathecae during the winter months. During the winter months
6 male Culex mosquitos were found from hibernating places searched. (Author's
abstract).
[영문]
Since Korea undertook a malaria pre-eradication survey in June 1959, several malaria endemic foci have been found in areas situated at the foot of the Taebak Mountains which run from north to south in the eastern part of the penninsula.
Plasmodium vivax is the only species reported from those areas.
Although a few reports on anopheline mosquitos have since been published in Korea, most of them were limited to report on the species and the seasonal prevalence of the population of the mosquitos.
An attempt was made, in this study, to incriminate the vector of P.vivax malaria and to elucidate the bionomics of the vector species in order to control the anopheline mosquitos in question.
In the first part of this study, the routine entomological work was carried out during the period of 1960-1961 in Yongju area, Kyongsang Pukdo of Korea according to the plan of operation for the malaria pre-eradication survey in order to incriminate the vector of malaria parasites and to elucidate the bionomics and
behaviour of the anopheline mosquitos.
During the survey, six anopheline mosquito species were recorded as follows and are listen in approximate order of decreasing frequency. However, Anopheles lesteri and A. lindesayi japonicus are probably the first to be recorded in Korea.
1. Anopheles sinensis Wiedmann, 1828.
2. Anopheles sineroides Yamada, 1925.
3. Anopheles koreicus koreicus Yamada and Watanabe, 1918.
4. Anopheles koreicus adwardsi Yamade, 1925.
5. Anophels lesteri Baisas and Hu, 19376.
6. Anopheles lindesayi japoniocus, Yamada, 1918.
A sinensis was the most predominant species and the next, A. sineroides, although A, koreicus Koreicus was found to be predominant after A. sinensis in Guidandong(a mountainous area).
Anopheline mosquitos begin to appear from late April or May and disappear in October each year.
The resting places for the anopheline mosquitos were mainly cow sheds and outdoors. The population density of A. sinensis is cow sheds showed a peak either in June or July in most places with a second small peak in late August or September.
Night biting habits appeared to be active throughout the whole night but were more active from when it was dark after sunset to midnight.
Most of the anophelines appeared to be zoophilic, though the precipitin tests for A. sinensis showed facultative anthropophilic.
Dissection of salivary glands of 2736 female a. sinensis resulted to prove no sporozoites.
The body weight, moisture and fat contents in A. sinensis appeared to decreased in July from a high peak in June and then to increase again in September.
Insecticide susceptibility tests proved that the species was susceptible to DDT and dieldrin.
The bionomics of A. sineroides, A. koreicus koreicus, A. koreicus edwardsi, a. lesteri, and A. lindesayi japonicus were discussed. Breeding places of A. sinensis were mostly rice fields and streams.
In the second part, a portable wooden hut designed by the author, with two windows in each of the four walls, fitted window traps and panels to catch anopheline mosquitos when they entered or flied off from the hut in villages near the tow of Yongju in Kyongsang Pukdo, one of the malaria endemic foci areas in Korea.
During 16 night catches between 10th June and 22nd August 1963, 5120 females of the species were caught in traps and in hut. Of them, 3223 were from entrance traps, 1605 from exit ones and 292 in the hut.
Four night catches in the entrance traps of 110, 140, 536 and 575 of a. sinensis and other four night catches in the exit traps of 59, 94, 179 and 55 are reported in detail.
They revealed that mosquitos were taken virtually in the entrance traps on the lee wards if the wind persisted from one direction, and fully fed mosquitos were taken in the exit traps on the windwards. But when the wind direction was variable
or conditions were calm, the resembling numbers of mosquitos were found in each of the four walls traps.
During the study, five high night catches were made, and the possible causes for the different size of catches in some factors were discussed.
Since much of high catches in this study occured in the darkness, it would seem that the mosouitos were attracted by the smells or odorous emanated from the host and that their approach to the hut was not directed a visual mechanism controlling
up-wind flight.
The rain throughout the night, did not prevent flight.
the two hourly collections, made from dusk to dawn, showed a curve of activity of A. sinensis, the greatest activity occurring between 22.00 and 24.00 hours. All the females taken in the entrance traps were unfed except 36 specimens with a partial
fresh blood-meal and 9 gravid. First entries occurred just before a complete darkness in the evening and the last in the good light after sunrise.
Males of A. sinensis were taken neither in the entrance traps nor the exit ones, nor in the hut. All the females taken in exit traps and in hut had fully engorged except 1 speciemens unfed. However, a curve of A. sinensis taken in the exit raps which flied off from the hut into exit traps after engorged, showed a gradual increase indicating a peak at 04.00-06.00 hour. About 15 per cent of A. sinensis fed on baited animal remained on walls of the hut until morning . After the species feeding on the host, they appeared to fly off to their resting places in nature
before day break. Therefore, this species would belong to Type A Senior-White's endophagy in a pre-determined exophily according to Gillies(1956).
The parous females of A. sinensis appeared to show a tendency to fly into hut from dusk throughout whole night, showing a peak at the period at 24.00-02.00 hour.
On judging from the Korean habits in local areas and behaviour of the species, the sinensis would transmit P. vivax malaria to man by bit6ing outdoor.
In the third part, the investigations on mosquito hibernation and physiology were carried out systematically in the vicinity of Seoul during the period of November 1959-April 1960 and of November 960-April 1961. Random survey was also done in
Kimhae, near Pusan in December 1959.
During the winter months, the following four species of mosquitos were found to hibernate in the adult stage.
1. Anopheles sinensis Wiedmann, 1828
2. Anipheles sineroides Yamada, 1925
3. Culex pipiens Linnaeus, 1758
4. Culex orientalis Edwards, 1921.
These anophelines caught in cow stables were all fed, showing that they could feed in winter. The most suitable places for the hibernation of Culex pipiens were culverts and caves.
The anophelines appeared to be less resistant to low temperature than the culicines.
Fat and moisture contents and body weight decreased in C. pipiens just before their hibernation was over, and no Japanese B encephalitis virus was isolated from the species.
The mosquitos caught in hibernating places were found to be unlliparcus and to have sperms in the spermathecae during the winter months. During the winter months 6 male Culex mosquitos were found from hibernating places searched. (Author's abstract).