Nghiên cứu mồi bả diệt muỗi và kết quả khảo nghiệm phòng trừ muỗi truyền bệnh ở Quảng Bình

DAI HOC QUOC
GIAHA NOI
TRl/ONGDAI HOCKHOA
HOC
Tl/NHIEN
IIA
Til!
QUYEN
NGHIEN
CUU M()I
BA DIET
MUOI
VA KET QUA
KHAO
N(,HIEM
PHONG
TRl/Mu6l
TRUYEN BENH
C*
QUANG
BINH
LUAN
AN
PHO
TIEN
SY KIIOA
HOC S/NH HOC
HaNAi
1995
MIJC LUC
Trang

1
I^cVi
ckm an
PHAN
L
MO
DAU
2
PHAN
n. LONG
QIJAN
lAl
LIEU 4
ILL
VAI
TRO TRUYEN BENH CUA MUOI CULICTDAE. 4
11.2.
DAC
TfNlI
SINTI
HOC CUA MOT SO
LOAl
MUCTl
C6
VAI TR6 TRUYEN
BENII,
10
11.2.1.
Tap
tinh

hiit
mdu cfia
muoi 10
11.2.2.
Tap tmh
trii
an
ctrn
muui.
11
11.2.3.
Sir
khdng
va
trdnh
tliuoc
diet
cia
muoi. 12
11.2.4.
Noi sinh
s&n
cua muoi. 13
1L2.5.
Cdc
yen to sinh
thdi
anh
Iiu6ng
den

cdc
quan the muoi
tiTTong
thhnh.
14
11-3.
CAC
BIEN
PHAP PHONG TRU
MUOI.
15
11.3.1.
Bien
phdp
hda hoc. 15
11.3.2.
Bien
phdp
sinh hoc. 20
11.3.3.
C^c
bien
phdp thu
(hap
vk
phong
chong muoi
khdc.
21
11.3.4.

Nhifng
cong
Irinh
nghien
ciiu
ve muoi
vk
nhiJng
hda
chat diet
muoi
chft
ycu
dri dirge
si^
dung
6"
Quhng
Binh.
22
PHAN
ML
TIlOl
GIAN,
DIA
DIEM vA PHUONG
PIlAP
NGHIEN CUU 24
iii.L
MOT SO DAC DIEM

TU
NHIEN
VA
KINH
TE
XA
HOT
d
QUANG
BINH
CO LIEN QUAN DEN SU
PHAT
TRlEN
CUA
MUOl.
24
III,
1.1.
Dae
diem dia
l5^
tu nhien. 24
I1L1.2.
Dae
diSin
khf
hau. 27
I1LL3-
Tmh
hlnh kinh

tc
xa
hoi. 29
111.2.
THOI
GIAN
vA DIA DIEM NGHIEN CUU 30
111.3.
PHUONG PHAP NGHIEN CUU. 35
IIL3.1
.Nghien
cifu
muoi. 35
III.3.2.Nghien
cifu
dieu che
vk
ifng
dung moi diet muoi. 37
PHAN
IV. KET QuA NGHIEN CUU. 42
CHUONG
1.
KET
QuA
NGHIEN CUU VE
MUCTl
CIJUC1DAB6
QUANG
BINH.

42
LI.
MUOI
ANOPHEUNAE.
42
LI.l.
Thknh
phan
loki vk su
phan bo. 42
LI.2.
Nhting h)hi
muoi
Anopheles
thu thap
duoc
bang
phuong
phdp
moi
ngudi
ban dem. 45
1.1.3.
NhUng loki
muoi Anopheles bat duoc trong
nhk vho
ban
ngky.
46
LI.4.

Mot so
lohi
muoi Anopheles
thudng
gap cd vai
tr6
truyen benh
6*
Qufing
Binh. 48
1.2. MUOI
CULICmAE
53
L2.L
Thknh
phan
loai vk
su phan bo
L2.2.
Su phan bo
vk
{^
le
(%)
cia muoi
Culex quinquefasciatus vk Culex
tiitaeniorhynchus.
54
1.2.3. Mat dp cua muoi Culex quinquefasciatus
vk

Culex tiitaeniorhynchus. 55
L2.4.
Aedes
aegypti, 58
CIIUaNG
2.
NGHIEN CUU
SAN
XUAl
MOI DIET MUOI. 62
2.1.
MUC
DfCH
NGHIEN CUU MOI
BA
DIET MUOI. 62
2.2.
CO S6
KHOA HOC CUA
VIEC
DIEU CHE MOI
DIET
MUOl
66
2.3.
XAC
DINH
CONG
THUC,
QUY

TRINH
SAN
XUAI
MOI DIET
MUOI.
68
2.3.1.
Xdc
dinh
thhnh
phan moi diet muoi. 68
2.3.2.
X^c
dinh loai hda chat diet con
titing
trong
moi diet muoi. 73
2.3.3.
Cong
thifc
dieu
die vk
quy trinh
sJin
xuat
moi diet muoi. 77
2.4. SU DUNG VA
BAO
QUAN
MOI

DIET
MUOl
79
2.5.
DOC
TfNH
CUA MOI DIET MUOl
DOl VOI
MUOl,
DOI
VOI
NGUOl
vA
DONG
VAT. 81
2.5.1.
Doc tmh
cfia
moi diet muoi doi
vdi
muoi. 81
2.5.2. Doc
tinh
cua moi diet muoi doi
vc^i ngud-i vk
dgng vat. 83
CHUQNG
3.
HIEU
LUC CUA MOI DIET

MUcTl IRONG
DIEU
KIEN
PHONG
THf
NGHIEM VA THUC DIA. 85
3.1.
DANII
GIA
HIEU LUC CUA MOI DIET
MUOl 6
TRONG PHONG
lUi
NGHIEM. 85
3.1.1.
Hieu
krc
cua moi
diet
muoi doi vdi muoi
An.
vagus. 85
3.1.2. Hieu
luc cha
moi diet muoi doi vdi muoi
Aedes
aegyqyfL
86
3.1.3.
Hieu luc

ctia
moi diet muoi doi
vd-i
muoi
Cule^
quinquefasciatus. 87
3.1.4.
D^nh
gid
su thu hut cua
mh\
diet muoi
vk
dgng vat
moi doi vdi muoi. 89
3.2. HIEU LUC CUA MOI DIET
MUOl
TRONG
PHAM VI THUC
DIA
HEP 91
3.2.1.
a Qu&ng
Binh.
91
3.2.2.
OH^Ngi-
92
3.2.3.
Thii

nghicm
xde
dinh thdi gian
tdc
dung ton
luu ciia
moi diet muoi tai thue dia. 94
3.2.4. So sanh mat do muoi dot
ngud'i o
noi cd
dilng
moi
vk
noi khdng diing moi. 100
3.2.5.
Thanh phan
lohi
muoi bi thu
hiit vh
diet. 105
3.2.6.
Tde
dung diet rudi cua moi diet muoi. 106
CHUONG
4.
KET QuA
KHAO
NGHIEM UNG DUNG
MOI DIET MUOI. 110
4.1.

TINH HINII
SU DUNG MOI
DIET MUOl
TRONG
CONG DONG. 113
4.2. SU DANH
GIA
VA CHAP NHAN CUA NHAN DAN
VE VIEC
su
DUNG MOI DIET MUOI. 113
4 3. CAC CHi SO MUOI vA BO
GAY.
^ 114
4.3.1.
Kct
quh
dieu tra chi so eon trung
cV
hai diem
(hi
nghiem
vk
doi
ehiing tru(fe
khi dat moi. 115
4.3.2.
Chi
so muoi trong thdi gian
thi

nghiem
dting
moi diet muoi. 116
4.3.3.
Chi so
bp
gay Aedes aegypti. 124
PHAN V KET LUAN 129
lAl LiftU TIIAM
KMAO
132
PHANL
M6
DAU
Mu6i
la
vit
tmng gian truyen
nhifeu
b^nh
nguy hiem
nhu
sot ret, sot
xuat huyet, viem nao Nhat Ban B, giun chi bach huyet Do c6 tam quan
trong dac biet do, nen da c6
nhieu
cong
trinh
nghien cuu ve khu he, sinh hoc,
vai tro

tmyen
benh va bien phap phong diet
mu6i.
Cac ket qua nghien cuu
khoa hoc da gop phan
giiip
cho loai
ngucd vugt
qua
dugc thtr
thach cua
nhihig
tham hoa dich benh nhu sot ret, sot xuat huyet, viem nao Nhat Ban B
[88].
O nucfc
ta,
tiJ
nhiing nam
dSu
cua the ky 20 da c6
nhirng
nghien cuu
v'h
mudi
nhu cua Laveran (1901), Stanton (1926), Morin (1930). Nhung nghien
cuu ve
mu6i
dugc thuc hien mot each c6 he thong a Viet nam c6 the ke
tif
sau

nam 1954 va dac biet dugc day manh
ti^
khi Vien Sot ret, Ky sinh
triing
- Con
triing dugc thanh lap (1957). Nhiing cong
tiinh
nghien cuu ve mudi c6 gia tri
dugc cong
b6
nhu cua Dang Van
Ngir
va cong su (1973) [34], Vu Thi Phan va
cong su (1975 [36],
Nguyin Hio
Viln,
Tran
Dure
Hinh va
c6ng
su (1975)
[63].
Cac nghien cuu chu yen tap trung vao viec xac dinh thanh phan
loai,
su phan
b6,
xac dinh vai tro tmyen
b6nh
ciia mot
s<5

loai muoi quan trong trong
nude,
trong
tijfng
khu vuc va nghien cuu ap dung cac bien phap diet vao thuc
ti^n
Viet nam.
D5i vdi
viec phong tru mudi
trudc
day cung nhu hien nay, bien phap
hoa hoc
vin
dugc coi la mot
bi^n
phap c6 hieu qua cao nhat. Cac hoa chat
diet mudi chu yen dugc diing duai dang phun ton luu, phun khdng gian, tam
man,
huong
xua
di^t
mudi,
kern bdi xua (Tran
Diic
Hinh, 1992)
[U],
Qua
trinh
thuc
hi^n phirang

thuc phun ron luu hoa chat diet da
xu^t
hien
mot
kho
khan
Idn
la mudi khang thuoc diet (Vu Thi Phan,
Nguyln
Van Chi va cdng
su, 1980)
[1,37].
Di&u
nay la mdt trong nhiing
nguy^n
nhan khdng hoan thien
trong cdng tac phong chong sot ret
of
mdt s6 nudfc
(Bmce
Chwatt,
1980) [72].
Hudtig nghien
cuu tim nhiing
bi^n
phap moi
b6
sung nhu
bi^n
phap sinh

hoc,
biy mudi, hoac hoa chat diet
mcfi,
ciing nhu cac phuang
thiic
su dung
hoa chat diet khac
vin
la
m<5i
quan tam hang
d&u di5i
vdi cdng tac phong
ch6ng mudi truyen benh.
Quang Binh la mdt
tinh
c6 dac diem dich
tl
hoc
ciia
cac benh do mudi
tmyen kha dien hinh.
Tinh
hinh sot ret
diln
bien
tuong
d6i
phiic
tap, dich sd't

xuat huyet Dengue
vin thu5ng
xay
ra,
viing luu hanh benh giun chi bach
huyet kha rong
[43,
44].Vi
vay
vi^
nghien
cuu mudi noi chung,
nhiJng
loai
mudi
CO
vai tro
tmyfen
benh quan trong noi rieng da dugc Tram Sot ret - Ky
sinh triing - Con
triing
Quang Binh thuc hien thuong
xuydn.
Trong do viec
di6t
mudi bang moi ba da dugc
nghidn
cum
tir
nam 1991 [15], la mdt phuang

thiic mcfi
su dung hoa chat diet bang phuang tien
mbi di^t
mudi
Vcd
nhimg
so lieu thu thap dugc trong qua trinh tham gia thuc hien, sau khi phan
tich
xu
ly chiing
tdi t6ng ket thanh luan an vol tieu de: "Nghien cuu mbi ba diet mudi
va ket qua khao nghiem phong tnr mudi tmyen benh
d
Quang Binh".
Ndi dung chii yen ciia
lusin
an
gbm:
* Xac dinh thanh phan loai va su phan
bd
ciia mot so loai mudi c6 vai tro
dich tl quan trong
a
Quang Binh.
* Nghien cuu dieu che, san xuat
mbi
diet mudi
* Danh gia
hitu
qua ap dung mbi diet mudi trong viec phong

chbng
mdt so
loai mudi c6 vai tro tmyen benh quan trong
a
Quang Binh.
* Kien nghi ap dung phuang
thurc mcfi
diet mudi
tmy'^n
benh bang mbi ba.
PHAN II.
TONG QUAN TAI LI$U
ILL VAI TRO
TRUYfiN B$NH
CUA
Mu6l
CUUCIDAE.
Bdnh
sot ret dugc biet den
tir
xa xua va luu hanh rdng tren the
gicfi,
htnh
xuat
hito
h^u
nhu khip cac
ch^u
luc.
B6nh sbt

ret gay
nhi^u
tac hai
dbi
vdi
siic
khoe con
nguci,
doi vdi kinh te - xa hdi
[84].
Nhung nam 1950, tren
th6'
gidi hang nam cd
sb ngucri
mac
b^nh
sbt ret
ucfc tinh
khoang 250 trieu
nguci, sb nguci chet vi sd't ret khoang 2,5 trieu
ngubi
(Bruce Chwatt, 1980)
[71].
Lan dau tien Laveran (1880)
&n thliy
ky sinh triing sbt ret (KSTSR) trong
mau ngoai vi cua mdt benh nhan
ngubi
Angieri Ronald Ross (1898) da xac
dinh dugc vai tro tmyen benh ciia mudi Anopheles va chu ky phat trien ciia

KSTSR trong ca the mudi va benh sbt ret dugc lan
tmy^n tiJ
nguci benh sang
ngubi lanh
qua mudi Anopheles
[35,47,85],
Til dd da ma ra mdt thci ky mci dbi
vdi viec
nghidn cuu
mudi sbt ret. Hang
loat
cac cdng trinh
nghien ciiu vfe
khu
h^,
sinh hoc, sinh thai hoc, vai tro
truyen
benh va bien phap phong diet mudi
da dugc tien hanh
[96.98,
loi,
103,104,105,106,107].
Chi tinh
rieng ve
ph^
loai mudi sbt ret da cd hang tram cdng
trinh
nghien
ciiu
vci gan khoang 300 bang dinh loai khac nhan. Ten

tubi
cac nha
khoa hoc: Leicester (1908), Stanton (1912), Reid (1968), Harison (1975)
Stojanovich va Scott (1966), Theobald
(1901-1910),,.
dugc biet den vdi cac
cdng trinh nghien cuu ve mudi sbt ret a An Do. Mien Dien, Inddnexia,
Hiilippin,
Thai Lan, Tmng Qubc,
[77,
82.102.109.
no,
iii].
Nghien
curu
ve sinh
hoc,
sinh thai hoc cua mudi cd rat nhieu cdng trinh, trong sb do cd cac cdng
trinh dang chu y nhu ciia Leicester (1903)
[81.
82], Bmce
Qiwatt
(1980)
[70.
71]
Su nhay cam cua cac loai Anopheles vdi DDT va cac
loai
thuoc diet con
triing khac c6 cac cong trinh ciia Davidson (1974)
[74],

Bruce
(Thwatt (1980)
172].
Herath va Davidson
(1980)
[78],
Suarez
(1990)
[108],
WHO
(1981) [i
18].
^
O
Vi^t
nam benh sbt ret luu hanh tren 3/4 lanh tho, vci hang trieu
nguci mac benh mdi nam (Dang Van Ngtr va cdng su, 1973)
[34],
Tir
dau the
ky 20, d
nude
ta da cd
nhiJng
cdng trinh nghien
ciiru
mudi nhung chii yen do
ngudi
nude
ngoai thuc hien.

laveran
(1901) da nghien curu d Bac bd; Bonet
(1906),
Morin (1930) nghien
ciin
mudi d mot sb diem thudc dbng bang Nam
Bg va Cdn Dao
[27].
Sau nam 1957 Vien Sbt ret, Ky sinh triing - Cdn trung
(Ha ndi) da cd nhieu cdng trinh nghien
ciJu difeu
tra ca ban mudi sbt ret tren
dien rdng toan mien Bac, Sb loai mudi Anopheles phat hien dugc la 56 loai
(Tran
Due
Hioh,
Nguyin Due
Manh, 1983)
[8,9].
Cac nghien cuu da xac dinh
dugc loai
An.minimus
la trung gian tmyen benh sbt ret d vung rung
niii
Viet
nam, Nhieu cdng trinh nghien cuu sinh hoc sinh thai hoc ciia mudi
An.minimus da dugc cdng bb:
Nguyin HiJu Dire
va cdng su (1973) [4],
Nguyen

Diic
Manh (1987)
[27],
Mudi
An.balabacensis
(hien nay ggi la
An.dirus) dugc xac dinh la tmng gian tmyen benh sbt ret chu yeu d vimg
rimg
ram,
rittig
cd tan (Dang Van
NgiJ,
Vu Thi Phan va cdng su, 1985) [38].
Ngoai ra cdn cd 7 loai mudi Anopheles khac ddng vai tro la vecta phu, tmyen
benh sbt ret d mdt sb viing: An.sinensis tmyen P.vivax d Gia Ninh, huyen
Quang Ninh, tinh Quang Binh
(Nguyin
Tho
Viln,
Nguyin Due
Manh va
cdng su, 1975)
[63].
Muoi
An.sundaiods
la tmng gian tmyen sbt ret chii yeu d
viing
ven bien mien Nam
(Nguyen
Tho

Viln,
Nguyin
Diic
Manh va cdng su,
1985)
[66].
Cac cdng trinh nghien cuu
bi^n
phap phong chdng mudi sbt ret
Cling da dugc tien hanh va dat ket qua:
Vii
Thi Phan, Tran
Due
Hinh va cdng
su (1980) [37]; Nguyin Van Chi va cdng su (1987)
[i],
C5 Mien
Nam, theo
•
6
cdng bb ciia Nguyin Thugng
Hien
(1968) cd 43 loai Anopheles. O Tay
Nguyen cd 38 loai (Nguyin
Due
Manh, 1987)
[27],
• Mac
dii
viec nghien cuu mudi ndi chung va mudi sbt ret ndi rieng dugc

tien hanh cham
hon
so vdi cac nhdm ddng vat khac, nhung phai
thira
nhan
rang ve
liiih
vuc nay nhanh chdng dugc nhfeu nha
klioa
hoc tham gia va
nghien cuu.
S6t xuat
huybt
Dengue thudng dugc goi la sbt xuat huyet. Tu han mot
thb
ky trudc da cd benh Dengue
cb
dien, benh nay khdng cd ty le tu vong cao
nhung sb ngudi mac rat
Idn,
Dengue cd kem theo xuat huyet ggi la Dengue
xuai huyet (hoac sbt xuat huyet). Dengue xuat huyet do 4
tip
ciia vims
Dengue (tip 1 den 4) thudc nhdm Arbovirus gay nen (Doan Xuan Mugu.
1979),
Day la mdt trong nhiing benh tmyen nhiem cd sb ngudi mac va ty le
tir
vong cao
[33].

Dengue xuat huyet phan bb d nhieu
nude
tren the gidi thudc
Chau A, Chau Phi Chau My, nhung
vimg
Ddng nam Chau A la nai cd benh
Dengue xuat huyet luu hanh nang nhat
(WHO,
1986)
[I2ij.
Vu dich sbt xuat huyet dau tien dugc ghi nhan d Philippin nam
1953.
Sau dd sbt xuat huyet xuat hien d nhieu noi: Thai Lan (1958), Malaixia,
Xingapo (1960), Inddnexia, Mien Dien
(1981),
6
Cu Ba (1977 - 1980)
Dengue xuat huyet trd thanh dich
Idn
(Pham Song, 1991) [55], Nhieu cdng
trinh
nghito ciiti
mudi da xac dinh mudi Aedes aegypti ddng vai trd tmng
gian truyen benh Dengue xuat
huybt:
Plotnikov (1964);
Pervomaiskyi,
Podoliana (1974); Zdanop, Gaidavich (1977) (theo Vi5
Due
Huong, 1984)

[18].
Nhieu
nude
da dua viec phong chbng mudi sbt xuat huyet thanh mdt
chuang
tiinh
qubc gia, trong dd cd
Xingapo,
Thai Lan
[76.121].
Q
Viet Nam, benh Dengue c6 dien da dugc
md
ta
tir
nam
1886
(Pham
Song, 1991)
[55],
Tir
nam 1960 benh Dengue xuat huyet xuat hien d mot sb
dia phuang Mien Nam. Nam
1969
dich sbt xuat huyet
bimg
phat d mot
sO
noi
nhu Ha Ndi, Hai Phong, Nam Dinh, Thai Nguyen, Nghe An

[is].
Tit
dd benh
Dengue xuat
huy^t
cd xu hudng phat trien va nhieu nam da xay ra dich
Idn.
Nam 1978 d
Mien
Bac cd 18.570 ngudi mac benh. 89 ngudi chet. Nam 1990
cd 75.310
ngirdi
mac benh, 102 ngudi. Nam 1987 Viet Nam cd 354.517
ngudi mac
b^nh
va 1,566 ngudi bi
ch^'t
[62],
Theo bao cao ciia Vien ve sinh dich tl (1993): Benh Dengue xuat
huyet phan bb rdng d cac quan , huyen, thi xa, thanh phb va mdt sb viing
ndng thdn trong ca
nude.
Dengue xuat huyet dugc coi la mdt trong sb 10
benh tmyen
nhilm
cd ty le tu vong cao nhat d Viet nam [62],
Vai trd chii
ybu
tmyen benh Dengue
xua[t huy^'t

d
Vidt
nam la mudi
Aedes aegypti. Nhieu cdng trinh nghien
ciiu
ve loai mudi nay da dugc cdng
bb nhu Vii
Diic
Huang (1984)
[18];
Vii
Dure Huong (1987); Le Khanh Thuan
va cdng su (1980 - 1989); Hoang Thiiy Nguyen
va
cong su (1986 - 1991);
Nguyin Thi Bach Ngoc,
Truong
Quang Hoc (1993) [32, 33], Vii Sinh Nam
(1995)
[30]
va nhieu cdng trinh khac.
Kbt
qua nghien
ciru
ciia cac tac gia da
khai quit dugc viing phan bb, vai trd dich tl, sinh hoc va cac bien phap
phong chbng mudi Aedes aegypti d Viet nam, gdp phan tich cue trong cdng
tac phong chbng sbt xuat
huybt.
Hidn

nay
bfnh
sbt
xu^t
huyet
v5n
dang la
mot van
dS
quan tam ciia xa hdi
Viem nao
Nhkt
Ban B (VNNBB) la mot
b^nh
nghiem trong xay ra tai
cac
nude
Viln ddng, Nam A va Ddng Nam A Benh cd ty le tir vong cao. Neu
bdnh nhan
hoi phuc dugc thi de
lai
di chung nang ne ve than kinh va tam
8
than. Tac nhan gay benh la vims
'^/N'NBB.
O An Do, vu dich dau tien xay ra
vao nam 1952, vims viem nao Nhat Ban B dugc phan lap tir mudi nam 1955
va
tir
ngudi nam 1958 (Schgal, 1989).

Tir
nam 1970 d An Do benh lan rdng
va trd nen tram trong. Nam 1980 cd 3.478 ngudi mac va 1.405 ngudi chet.
Chinh
phii phai dat van de nay thanh mdt
nhi^m
vu trong
ybu
trong viec bao
yt sue
khde cdng dbng. Cac tac gia d An Do da xac dinh dugc
11
loai mudi
thudc 3 gibng: Culex, Anopheles, Mansonia ddng vai trd tmng gian tmyen
benh VNNBB, trong dd Culex tritaeniorhynchus la loai quan trong
nhatt
(Schgal,
1989)
[99],
6
Inddndxia,
Thai Lan, Nepan, Nhat Ban , benh VNNBB
Cling la mdt van de dugc nhieu tac gia nghien cuu [92,123,124]. Leake va
Johnson (1987)
[83]
da phan
Mp
dugc vims VNNBB
tir
mudi Culex

tritaeniorhynchus ddng vai trd
chinh
tmyen benh VNNBB d cac
viing
da
nghien
ciiu.
O
Viet nam nhieu tac gia da nghien cuu ve cac mat lam sang, dich tl
hoc,
vims va cdn triing, da phan lap dugc vims VNNBB va nhan dinh nhdm
mudi Culex tritaeniorhynchus va Culex vishnui cd lien quan den
miia
dich
VNNBB (Vu Sinh Nam, Nguyin Chac Tien va cdng su, 1985) [29]. Doan
Xiian
Mugu va cdng su
(1965)
Ian dau tien da phan lap dugc vims VNNBB d
chim
Lieii
Dieu va thay 8 loai chim khac nhau cd nhilm vims VNNBB. Lgn
la gia
siic
mac benh VNNBB phb
bi6i
nhat d Viet nam. Cac ddng vat khac
nhu trau, bd, ngua, khi, chd, ga, vit ciing cd
chiia
vims VNNBB nhung ty le

thap hon so vdi lgn (Dd Quang Ha, 1978). Gan day benh VNNBB cd chieu
hudng tang
len
d mien ddng bang va dd
thi,
cd
liic
da xay ra dich. Tiiy theo
tijmg
dia phuang khac nhau ma
miia
dich cd khac nhau.
d
Mien Bac Viet nam
b^nh
thudng xay ra
tijr
thang 4 den thang 9 (Nguyin Thi Bach Nggc
j
1995)
[33].
Benh giun chi bach huyet la mdt benh ky
siah
triing mang tinh chat xa
hdi rdng.
B^nh
do 3 loai giun chi Wuchereria
bancorofti,
Brugia
malayi,

Brugia timori gay nen, Benh giun chi bach huyet thudng luu hanh d cac
nude
nhiet
dcd
thudc chau A, Chiu Phi,
Qiau
My va mdt sb dao d
viing
Thai
Binh
Duangtiu].
Benh nay khdng nhiing chi anh hudng den
siic
khde con ngudi
ma cdn de lai nhiing di chung nhu viem bach mach, phu voi Ky sinh triing
dugc tmyen
tir
ngudi benh sang ngudi lanh qua mudi (Nguyin Duy Toan,
1987) [52, 53]. Manson (1978) phat hien thay an triing giun chi Wuchereria
bancorofti phat trien trong ca the mudi va au triing thanh thuc cdn thoat
ra
khdi vdi cua mudi Culex fatigans. Tren the gidi cd khoang 3.287 trieu ngudi
sbng trong viing cd benh giun chi bach huyet luu hanh [53].
(J
Vi6t
nam giun chi bach huyet luu hanh d hau het cac
tinh tiiudc
viing
dbng bang Bac bd nhu Nam Ha, Hai Hung, Thai Binh, Ha Ndi, Ha Tay,
Ha Bic, Quang Ninh va Quang

Binh
[57]. Benh giun chi bach huyet d Viet
nam thudng de lai di chiing phii d chan nen nhan dan thudng ggi la benh
chan voi Mathis va Leger
(1911)
da nghien cuu benh nay,
thir
man cho gan
2000 ngudi thudc 10 tinh dbng bang Bac Bd va thay ty le nhilm au trung
giun chi trong mau ngoai vi la 4,69%. Sery va Pham Van Ndng (1960 -
1975)
da phat
hi^n
d Hai Duong ty le nhilm au triing giun chi la
15%.
Theo
Nguyin Duy Toan (1985) [52] thi
tif
nam 1960 - 1975, ty le nhilm au
trimg
giun chi chung ciia Mien Bac la
6,01%;
O Quang
Binh
ty le nhilm au thing
giun chi la
11,7%.
Quang Binh cd khoang 40.000 ngudi sbng trong
viing
cd

benh giun chi luu hanh va ty
\t
nhilm au trung d 2 xa Hai Ninh va Gia Ninh
huyen Quang Ninh la 2,30% [44]. O Mien Nam benh giun chi bach huyet
khdng dang ke
[53].
Nhieu cdng trinh
nghi6n ciiu
lam sang va dfeu tri benh
giun chi bach huyet da dugc cdng bb nhu Dang Van
Ngii
va cong
sir
(1960,
10
1965),
Bach Qubc Tuyen (1963) [33]. Cac nghien
ciiu
ve mudi da xac dinh
dugc vai trd tmyen
benli
giun chi d Viet nam la Culex quinquefasciatus,
Mansonia
annulifera,
Anopheles sinensis (Tran
Diic
Hinh, Nguyin Bach
Nggc, Vu
Diic
Huong, 1987)

[lO].
Cho
d^n
nay d Viet nam mdi chi gap 2 loai
giun chi bach huyet la
W.bancrofti
va
B.malayi,
trong sb dd B.malayi chiem
X&i
95% (Nguyin Duy Toan, 1987)
[53].
IL2.
DAC TINH SINH HOC CUA
MOT sd
LOAI
Mu6l
CO VAI TRO
TRUVfeN
B$NH.
n.2.1.
Tap
tinh hiit
mau
ciia
muoi.
Pha trudng thanh la giai doan sbng tren can duy nhat trong vong ddi
cua mudi Mudi
due
khdng

hiit
mau, chi sir dung ngudn
thiic
an tu nhien nhu
mat hoa va dich trai cay, nhua cay lam
ch^t
dinh dudng. Mudi cai
hiit
mau
ddng vat va ngudi, dd ciing la chat dinh dudng bat budc de nudi ca
th^
va
phat trien
tning.
Khdng
hiit
mau thi mudi khdng the thuc hien dugc chu ky
sinh
tmdng
binh thudng. Mdt sb nghien
ciiu
(Bmce Chwatt, 1980)
[71]
da neu
len rang: Mudi cai ciia hau het cac loai it nhat phai hai lan dbt mau thi
Id
tning dau tien mdi phat trien dugc. Nhiing chu ky tiep theo thi sau mdi lan
hut man mudi lai de tning. Mudi cai thudng dbt ddng vat man ndng,
lugng
mau tieu thu dugc khoang bang trong lugng ca the mudi. Mau trong da day

mudi dugc tieu hda trong mdt vai ngay (Bmce
Cliwatt,
1980).
Mudi
CO \Mi lua
chgn vat chii, Nhiing loai mudi khac nhau thi khac
nhau ve ai
tihh vM
chii. Trong dieu kien thuan
Igi
mudi cd the lua chon vat
chu thich hgp nhat, nhung trong nhung dieu kien khdng thuan
Igi
mudi cd the
thay dbi vat chii. Mot sb loai thich vat chii la ngudi nhung ciing cd the
hiit
mau
dgng vat hoac
agugc
lai Trong thuc te cdn cho thay rang tham
chi
mudi
11
cai
CO dii
hut
audc
dudng trong dieu
Icien
bat bucc de duy

tn sir
song. Trong
so nhimg yen to thu
hiit
mudi cai den vat
chii
thi nhiet do,
miii
vi, lugng
CO2
la quan trong (Bmce Chwatt, 1980).
Yeii
to nay cd
th^
thu hut dac biet dbi
vdi loai mudi nay nhung dbi vdi loai mudi khac thi it hon. Cac dgng vat khac
nhau cd su thu
hiit
mudi khac nhau. Mdi loai mudi cd thdi gian hoat ddng tim
mbi khac nhau, Mudi Anopheles va
muoi
Culex thudng dot mau vao ban
dem, mudi Aedes chu yeu
hiit
man vao ban ngay. Khi mudi dbt, dich trong
tuy6i
nude bgt ciia mudi dugc tmyen qua vat chii, lam tang qua trinh chay
mau trong mao quan.
Vi
vay viec dbt mau vat chu la nguyen nhan de mudi

ddng vai trd tmng gian tmyen benh cho ngudi va ddng vat (Bmce Chwatt,
1980).
IL2.2.
Tap tinh tru an
ciia
mudi.
Sau khi giao phbi mudi tim mbi
hiit
mau rbi tim noi tni an de tieu mau
va phat trien tning.
Noi tni an cua mudi rat da dang,
tiiy
theo cac loai mudi khac nhau ma
cd nhiing noi tni an khac nhau [69]. Cd nhihig loai tim mbi
hiit
mau trong nha
rbi nghi lai d trong nha. Mudi cd
thi
d^u
vao tudng vach, vach ngan,
quto
ao
treo trong nha, bb thdc, mat sau ciia tii, tranh anh, chan bat Trong thuc te
thudng bat gap mudi dau d do cao dudi 2 met.
NTiimg vimg
cd phun DDT d
do cao tir 2 met trd xubng, da thay hien tugng mdt so loai mudi Anopheles tni
an d trong nha tranh thudc diet bang
each
dau d nhiing noi cao han, nai

khdng cd hda chat diet (Nguyin
Diic
Manh, 1993)
[28].
Ciing cd nhiing loai
tim mbi
hiit
mau trong nha rbi bay ra tni an ngoai tu nhien, hoac ngugc lai
Nai
tiL m
cua mudi d ngoai thien nhien thudng la cac
biii
cay, hoc cay,
rl
cay
Idn,
ham ho,
'.e aiit
cua
aui
da.
Tliirdng muoi iyu
dau
y aoi Ididng
c6
<inh
12
sang mat
trdi
doi

tnrc
tien,
c6
do
im
dam bao, c6
vi
khi hau thich hgp.
"^-/ao
miia
he mudi thudng tim nai tni dau thap. c6 nhiet do thap, do am cao. Dudi
tac dung cua
viec
diing hda chat diet mudi da dan den mdt sb loai muoi thay
dbi tap tinh tni an von cd cua minh de
phii
hgp vdi
dieu
kien mdi trudng sbng
nhu An.minimus d Mien Bac da cd hien tugng tranh DDT, thay dbi
t^p
tmh
tni an trong nha ra tim nai tni in ngoai nha (Nguyen
Diic
Manh,
1993)
[28].
II.2.3.
Su khang va tranh thuoc diet cua muoi.
Su khang cac loai thuoc diet cdn triing dugc coi nhu la mot hien tugng

sinh hoc
ciia muoL
Hien tugng sinh hgc nay dugc hinh thanh do viec su dung
khdng hgp ly hda chat diet mudi (Bmce Chwatt, 1980)
[72].
Khi mdt quan the cdn triing tiep
xiic
vdi mdt hgp chat doc thi se cd
mdt phan chet. mot phan cdn sbng sdt lai Hien
tugng
dd goi la
Idiang
sinh
ly. Be ngoai ciia hien tugng nay la su thay doi tap tinh
ciia
quan the cdn
triing, bdi the ma chiing c6 kha nang tranh tiep
xiic
vdi thudc diet. Hien
tugng nay
ggi
la
Jdiang
tap tinh hay
tranli
thudc (Bmce Chwatt, 1980). Ca hai
loai khang thubc deu cd the han che ket qua cua cac bien phap phdng chbng,
dac
bi^t
la bien phap phun thubc

didt
cdn trimg cd
tirih
chit
fdn
luu.
Nhieu nghien
ciiu
(Herath va Davidson, 1980; Bmce Chwatt, 1980)
[72.
78] Cling da cho biet ban chat va ca che
ciia
su khang thubc la vai trd
ciia
cac
yeu tb di tmyen, yeu to tac ddng va yeu to sinh hoc. Su khang thudc tang len
trong qua trinh chgn
Igc
va
chi
xay ra d mot sb loai mudi ma ngay tir dau da
cd mdt ty le ca the mang tmh di tmyen cd kha nang
ciio'ng
lai doc to cua
thudc diet,
Nhirne
ca the nhay
thi
chet.
nhuns en

the c6 kha
nan« chbnii
lai
thudc diet
thi sdn,s
sot
'/n
phat trien
^•Ing.
len ra'i
nhanh.
Dea xxict
giai doan
nao do quan the
.nnuoi chi
cdn
lai ahirng
ca the khang thudc
hoan
tokn.
13
Theo thong ke
ciia WHO (1977)
thi nam
1944
tren the gidi mdi chi cd
2 loai Anopheles khang DDT. Nam 1976 cd 43 loai
Idiang
vdi mdt hoac
nhieu loai hda chat diet. Mdt so

nude
da thay bang cac
loai
hda chat diet
thudc nhdm Phbt pho
hiiu
ca (Malathion) va nhdm
Carbamat.
Tuy nhien sau
dd ciing xay ra hien tugng mudi khang vdi cac loai thubc diet nay. Tinh den
nam 1992 tren the gidi cd
Idioang
45 loai mudi Culicinae khang vdi mdt sb
hda chat diet (WHO, 1992)
[33],
O Viet nam cd nhieu cdng trinh nghien
ciiu miic
do nhay cam vdi cac
loai thubc diet trong qua trinh phdng chbng mudi tmyen sbt ret, sbt xuat
huyet. viem nao Nhat Ban, giun chi. Cd the neu dien hinh mdt so cdng trinh
nhu Vii Thi Phan, Nguyen Van Chi, Nguyin
Xhan
Dinh, Nguyin Thi
Phiic
va
cdng su (1980) [37]; Nguyen Van Chi, Nguyin Xuan Dinh (1981 - 1985)
[i];
Thdng bao ve tinh hinh khang
tliudc
diet

ciia
muoi d
Binh
Tri Thien ciia Ha
Thi Quyen (1987)
[42].
Trinh Dinh Dat va cdng su (1993) da nghien
ciiu
xac
dinh
miic
do va dac diem di tmyen khang thudc trir sau cua mudi
Cx,quinquefasciatus
[2, 3].
fCet
qua nghien
ciiu
ke tren deu thbng nhat nhan
dinh rang d Viet nam da cd mdt sd loai mudi
Anopheles,
Culex, Aedes cd
hien tugng khang hda chat diet nhu An.vagus, An.sinensis,
An.sundaicus,
Aedes aegypti, Culex quinquefasciatus, Culex
tritaeniorhynchus M6t
sb loai
xuat hien tap
tinh
tranh thubc diet, trong sb dd cd An.minimus da duac
nghien

ciiu
rat ky
ludng
va the hien tap tinh nay kha rd rang (Nguyin Tho
Viln, Nguyin
Diic
Manh va cdng su)
[64,65].
IL2.4.
Noi sinh
san ciia
mudi.
Tning mudi
ludn ludn
dugc de trong mdi tmdng
nude.
Nhiing yeu tb
lien quan tdi nai sinh san cua mudi bao gbm
nude,
anh
san",
nhiet dd, dd
14
man. lugng chat
huii
ca. ddng chay, thuc vat
thiiy
sinh , tuy theo
timg
loai

mudi va su thich nghi cua chiing vdi nhimg dieu kien mdi trudng. Nhung nai
sinh san ciia mudi thudng gap d nhung subi chay
cham,
dam Fay, ao ho,
gieng,
vung
nude
dgng tren ddng mdng, mgng
liia,
hbc cay, be
chiia
nude,
vet
nude
dgng tren dudng, cac dung cu phe lieu cd
chiia nude
v.v Hau het
cac loai mudi deu cd cac giai doan tir tning phat trien thanh bo gay rbi phat
trien
dianh
quang deu xay ra d trong nude. Mdt chu ky tir tning den mudi
tmdng thanh ciia mudi Anopheles khoang 7-8 ngay d nhiet do
31°C
va 20
ngay d nhiet do
20°C.
Tuy nhien mdi loai cd mdt gidi han nhiet do thich hgp.
Nhung vat chiia
nude
nhan tao nhu

Ig,
chau,
thiing
phi
Ibp
d to hdng cd chiia
nude
thudng la noi thich hgp cho mudi Aedes de tning, trong
liic
mudi Culex
quinquefasciatus lai thich de tning d nhung cdng ranh trong mdi tmdng dd
thi noi cd lugng chat hiiu ca nhieu (Bmce Chwatt, 1980)
[i].
Viec kiem soat mdi tmdng sinh san ciia mudi va can thiep bang nhiing
bien phap thich hgp trong giai doan phat trien trong mdi tmdng
nude
cua
mudi cd y
nghia
lam giam mat do quan the mudi tmdng thanh.
IL2.5.
Cac yeu tb sinh thai anh hudng den cac quan the mudi trudng
thanh.
Vong ddi ciia mudi cd bdn giai doan. Giai doan tning, bg gay, quang
hoan toan tdn tai va phat trien trong
nude.
Giai doan tmdng thanh song tren
can. Ca bbn giai doan nay deu chiu anh hudng hoac
true
tiep, hoac gian tiep

ciia
cac yeu tb sinh thai bao gbm cac yeu tb tu nhien nhu nhiet dd, dd
Eim,
anh sang,
nude,
gid
ma chung
qui lai
la
thdi
tiet,
khi hau va mdi quan he
giiia
mudi va cac loai sinh vat khac. Ngoai ra mudi cdn chiu anh hudng cua nhiing
tac ddng do hoat ddng cua con ngudi gay nen nhu hoat dgng ndng
ngiiiep,
15
thiiy
Igi,
dot
rimg
khai hoang, trong rimg, sir dung hda chat trong nong
nghiep, trong y hgc du phdng v.v , Nhiing
yeii
td tren quyet dinh su phan bb
thanh phan
loai,
mat do cua mudi theo timg viing, dia phuang, timg sinh
canh,
anh hudng den su ton tai va phat trien binh thudng ciia mudi Qua qua

trinh chgn
Igc
tu nhien ma ket qua la mdt sd loai mudi da thay dbi tap
tinh
von cd ban dau
ciia
minh de
phii
hgp vdi dieu kien
mdi
trudng song.
Cung nhu cac loai con triing khac. dbi vdi mudi thi thiic an, cu the la
vat chii la nhan td quan trgng nhat anh hudng
true
tiep den
sir
siuh tmdng,
phat trien va tap tinh
ciia
mudi 0 mudi su phat trien
ciia
tning
gdn
lien vdi
dinh dudng cua con cai
sir
tieu mau song song vdi su phat trien ciia tning
trong bubng tning. Khdng
hiit
dugc mau thi tning khdng phat trien. Sb Tan de

tning
CLia
mudi tuong ung vdi sd lan
hiit
mau (Olxufev, 1940; Beklemisev,
1944)
[46.75].
Su
bien
ddng quan the cua mudi lien quan den cac dieu kien cu
the ma quan the ton tai trong dd. Viec
sir
dung hda chat trong ndng nghiep,
thudc diet trong phdng chdng muoi la yeu td tac ddng manh me nhat den
quan
tlie
mudi
1^
giam rd ret sb lugng ca the va thay ddi cua cac quan the
mudi.
II.3.
CAC
BI£N
PHAP
DI£T
MU6I
CHU
Y^U.
IL3.L Biep phap hoa hoc.
Iheo WnO

(1990 - 1991) thi trong cac bien phap phdng chbng mudi
tmyen benh, bien phap hda hgc ddng gdp tich
cue
va cd hieu qua nhat. Cd
den hang tram hda chat da dugc nghien
cini
img dung dudi nhieu dang khac
nhau nhu phun tbn luu, phun
Jdidng
gian, tim man,
tim
rem. huong xua diet
mudi kem
bdi
xua
v.v,.,
[i
1.12.13.14.40.122].
Cd the chia cac
loai
hda chat diet
thanh cac nhdm sau.
16
1.
Nhdm
Clo
hiiu
co.
- DDT
(Diclo

diphenyl trichloroetan) la hgp chat dien hinh thudc nhdm
nay da dugc sir dung. Nam
1948
Ponmuyle (1899 - 1965) da dugc trao giai
thudng Nobel ve cdng
lao
phat hien tac dung diet cdn triing het
siic
cong hieu
cua DDT.
DDT
CO
thdi gian tac dung tbn luu dai he sb an toan la 67 nen to
chiic
y te the gici
(WTIO)
da quyet dinh dua vao sir dung trong chuang trinh thanh
toan sbt ret toan cau va da dat dugc ket qua het
siic
to
Idn.
Sau chien tranh
the gidi
thii
II, DDT dugc su dung rdng rai tren toan the gidi. Nhd sir dung
DDT ma hang nam da
ciiu
dugc hang chuc trieu ngudi khdi chet vi cac benh
hiem
nglieo nliu

sbt ret, sbt xuat huyet, sbt vang. Nhieu
nude
thudc viing dn
ddi da thanh toan dugc benh sdt ret nhd sir dung DDT diet tmng gian tmyen
benh
[72,89],
DDT dugc sir dung
chii
yeu dudi dang phun tbn luu vdi
lieu
lugng
2gAn".
Viec su dung DDT chi sau mdt thdi gian ngan da xuat hien
mudi
khang loai hda chat nay va
miic
do khang tang dan len rat nhanh. Dd la
nguyen nhan
chinli
dan den
tliat
bai trong chuang trinh thanh toan benh sdt
ret d nhieu nude (Herath va Davidson, 1980)
[78].
Mat khac ciing nhan thay dugc rang DDT phan huy trong dat rat cham,
cd the tbn luu trong dat khoang 25 nam, cd the dugc tich
liiy
lai va dat ndng
do tang dan theo chudi thuc an tir thap len cao
ciia

sinh vat. Trong vong 30
nam
k^
tir
1942 tren the gidi da sir dung khoang 2 trieu tan DDT. Qua kiem
tra ngudi ta
nlian
thay DDT cd mat khap mgi noi ke ca trong mo md va sua
ciia
con ngudi. DDT hda tan vao
nude
bien, tham nhap ca vao
chun
canh cut
dt^in cue
bac xa xdi (Bmce Chwatt, 1980)
[72].
Tii nam 1970 nhieu
nude
tren
the gidi trong dd c6 Lien Xd da bat dau cam
s;in
xuat va sir dung DDT.
17
d
Viet nam DDT dugc bat dau sir dung vao nam 1955. Nam 1962,
DDT dugc
dimg
diet mudi trong chuang trinh thanh toan sdt ret d 28 tinh
ciia

Mien
Bdc.
DDT da dugc sir dung trong mdt
thdi
gian rat dai (30 nam) vdi
mot sd lugng rat
Idn,
hang ngan tan trong mdt nam, gdp phan dua lai ket qua
dang ghi nhan trong chuang trinh phdng chdng sdt ret d Viet nam. Cac cdng
trinh theo ddi su nhay cam cua mudi vdi DDT dugc
tien
hanh rat kip
thdi
(tu
1962) va
tliudng
xuyen,
da phat hien dugc mot so loai mudi khang DDT hoac
da tang
siic
d^
khang vdi loai hda
chit
nay.
Vi
vay nhimg nam gan
diy,
DDT
chi cdn dugc
sir

dung d mdt sd viing mien
niii
va tmng du. nai cd
An.minimus va An.dirus cdn nhay cam. Hien nay dang cd xu hudng ngimg su
dung DDT trong
linh
vuc y hgc du phdng.
2.
Nhdm lan hiiu ca.
- Malathion la hgp chat phot pho hiiu ca chinh dugc sir dung phdng
diet mudi cd he sd an toan la 50. Malathion cd tac dung diet cdn triing manh,
nhung tac dung tbn luu qua ngan, thudng chi keo dai tir 1 den 2 thang.
Vi
vay
Malathion chi dugc diing chbng dich d dang phun
klidng
gian. Mdt sb loai
mudi da khang
loai^hda
chat nay (Davidson, 1974)
[74].
- Sumithion da dugc diing dudi dang khi diing de diet mudi Aedes
aegypti cung cd ket qua (Nguyen Thiiy Hoa, Nguyen Chac Tien va cdng su,
1992)
[30],
3.
NTidm
Carbamate.
- Hop chat chinh trong nhdm nay dugc sir dung trong viec phdng
chdng vecta la Propoxur: 2 -

M-Methylethoxy)
phenyi
methvlcarbamate
(CAS).
He sb an toan la 13. Propoxur tac ddng doc qua dudng tieu hda va
tiep
xuc,
Nhieu
nude
da diing Propoxur de chbng dan dudi dang mdi 2% do
!rn
\m:{'yv<ij-xx
L
^yy/^5s'
sfefeM
18
doc tinh tieu
hda.
Dang phun dung dich
i%
cd tac dung ton luu
lau,
dugc
diing de diet mudi mbi kien, ve va nhieu loai chan dot
khac.
Vdi lieu lugng
2gym"
phun ton luu tren tudng, Propoxur cd tac dung diet
mudi
trong 3 thang.

Propoxur cd doe tinh thap vdi ngudi vdi ddng vat cd
vii,
la hgp chat cd the
thay DDT d nhiing nai da cd mudi khang. Viec sir dung Propoxur chua rdng
rai vi gia thanh cao va he sd an toan thap
(Mohneaux
va
Gramiccia.
1980) [73.
86,
87].
Propoxur cd tac ddng d at, hay cd doc tinh
kicii diich
budc cac loai
con triing rdi khdi nai tni an va do dd tang su tiep
xiic
cua chimg vdi hda
chat diet dugc phun len cac be mat. Day la dac tinh khac biet vdi cac loai hda
chat diet cdn triing khac.
O Viet nam, Propoxur da dugc diing diet mbi dan dudi dang mbi doc
2%
(Nguyin Chac Tien, Pham Thi Nggc Diep, Nguyin Thiiy Hoa, 1989) [49,
50].
Chiing tdi chua thay cd tai lieu nao neu len
sir
dung Propoxur de diet
mudi
4.
Nhdm
Pyrethroid.

Qua
danli
gia cua WHO (1992) thay rang: Hien nay the gidi cd xu
Iiudng sir
dung cac hda chat diet thuoc
nlidm
Pyrethroid tong hgp dudi dang
phun tbn luu, phun khdng gian, tam man, tam rem. tam quan ao, huong xua
diet mudi de diet mudi phun xudng
nude
de diet bo gay
[14,
9i.
95.
lOO].
Dac
tinh chung
ciia
cac hda chat thudc nhdm nay la it doc vdi ngudi va ddng vat
man ndng, cd hieu luc
di^t
cdn triing rat manh qua dudng tiep
xiic
va xdng
hai,
Chiing vira cd tac dung diet mudi tuc thdi vira cd tac dung diet tdn luu
keo dai tir bdn den nam thang, viia cd tac dung xua dudi con trung rat manh
so vdi cac chat da
sir
dung, Cac hda chat tliudc nhdm nay deu hda tan tdt

trong
nude,
trong cac dung mdi huu ca, dudi tac dung
true
tiep
ciia
anh sang
19
mat trdi ddc tmh bi giam nhanh. Co the ke den mdt sd hda chat thudng dugc
sir dung nhu:
-
Permethrin: He sb an toan 516. Hinh thiic sir dung
chii
yeu la tam
man,
tdm
rem vdi lieu lugng 0,2 -
0,5g/[n".
0 Viet nam bat dau sir dung
Permethrin tir nam 1986. Da cd nhieu cong trinh nghien
ciiu
ung dung
ttoi
man Permethrin trong cdng tac phdng chdng sdt ret. sdt xuat huyet, giun chi
khang dinh cd hieu qua rd ret, dac biet d nhimg viing cd muoi idiang DDT
(Nguyin Long Giang, Nguyin Thugng
Hien,
Pham
Tlii
Hda va cdng su,

1990
[5,6];
Vii
Diic
Huong va cdng su, 1993 [23];
Vii
Sinh Nam, 1995 [30]).
- Deltamethrin (K Othrine).
Tii nam 1977 den nay nhieu
nude
da
ling
dung Deltamethrin trong
phdng chbng sbt ret dudi hinh thiic tam man hoac phun tbn luu tren tudng
vach.
d
Tmng Qudc sir dung Deltamethrin
ttoi
man vdi lieu lugng
25mg/m^
de phdng chdng sdt ret bao ve hang chuc trieu ngudi O Viet nam da cd nhieu
cdng trinh nghien
ciiu ling
dung Deltamethrin dudi hinh thiic tam man vdi
litu
lugng
lOmg/m
va phun tbn luu vdi lieu lugng
15mg/ni'
thay cd tac dung

tdt vdi mudi tmyen sbt ret va sbt xuat huyet tren 5 thang. Sir dung
Deltamethrin dugc nhan dan hudng
ling vi
hda chat nay cdn diet duac rep, bo
chet, dan, mbi va it de lai dau vet tren do vat. Ciing nhu Permethrin, hien nay
Deltamethrin dang dugc su dung rdng rai.
- ICON (Lamdacyhalothrin).
I^
hda chat diet cdn trimg manh, cd trien vgng ling dung rdng.
()
Viet
nam Icon dugc sir dung dudi dang phun tbn luu vdi lieu lugng
30mg/ni^
d
mdt sb viing
dii
diem va nhan
th^y
tac dung fdn luu keo dai 9 thang tren cac
loai vach
g6,
niia.
Dbi vdi tudng gach vdi tac dung tbn luu chi keo dai 1
20
thang.
Vi
vay khdng nen
sir
dung Icon d nhiing vimg cd nhieu nha gach
(Nguyin Thugng

Hien,
Nguyin Long Giang,
1993)
[6].
II.3.2.
Bien phap sinh hoc.
Viec ap dung cac bien phap sinh hgc de phdng chdng mudi la mdt
hudng chinh trong chuang trinh nghien
ciiu
mudi tmyen benh.
Cung nhu cac loai cdn triing khac, trong ddi song tu nhien mudi
thudng gap phai nhung thien dich khac kim ham su sinh san va phat trien cua
minh.
Cac nha khoa hgc da di sau nghien
ciiu
linh vuc nay va da kham pha ra
nhiing nhan td sinh hgc cd kha nang ung dung dugc trong viec phdng chdng
mudi d ca hai giai doan tmdng thanh va bo gay dd la cac
loai
vi
Jdiuan,
virus,
nam, ca v.v [68, 120]. Trong mdi tmdng
nude,
cac loai ca gdp phan quan
trgng trong viec diet bg gay cua mudi Costa va Femando (1975-1985) cho
rang cd 3 loai ca cd kha nang diet bg gay d Srilanca.
lakhontov
(1972),
Motabar (1975 - 1985) cho rang: Dang luu y han ca la ca Gambusia

affinisis,
trong 24 gid mdi con ca cd the bat dugc 200 bg gay
[25.46.
68].
Cac tac gia
cd cdng trong viec
khing
dinh kha nang diet bg gay cua Bacillus
thuringiensis la Kramer, Garcia,
Colwell,
1985 [80,
120].
Uy ban bao ve mdi
tmdng cua My da nghien cuu kha nang gay benh cho mudi
ciia
nam Fungus
lagennidium gigantium. Cdn cd rat nhieu cdng trinh nghien
ciiu
khac da va
dang tien hanh vdi nhiing khia canh khac nhau
[68.97.
ii7].
O Viet nam, viec phdng chdng mudi bang bien phap sinh hoc ciing da
dugc
nghidn
ciiu.
Nguyin Van
Chi,
Nguyin Thuy Hung va cong su (1987) da
xac dinh dugc 9 loai ca cd kha nang an bg gay va cd the

ling
dung trong cdng
tac phdng chbng sbt ret. Nguyin Thg Viln,
Tr^
Dire Hinh (1990) cho thay
rang bang
bifn
phap tha ca chep lai Hung
(Cyrinus carpio) kich tliudc
tif 4 -
21
6 cm vdi mat do tir 4 - 6
conAn^
nude,
vao be
nude
an d nhiing vimg dbng
bang cd bg gay An.minimus da cd hieu qua lam giam mat do An.minimus rd
ret. Nguyin Thi Bach Nggc,
Tmong
Quang Hgc (1993) [32] cho thay bien
phap tha ca vao be nude va quan ly ve sinh mdi tmdng la rat cd hieu qua,
khdng
chb
den
miic
thap
nh&
mat dd mudi Aedes aegypti va chi sd Breteau.
Nguyin Thuy

Hiing
va cdng su nghien
ciiu
diing che pham Bacillus
thuringiensis, dau huang nhu de diet bg gay
[17,
24j.
II.3.3.
Cac bien phap thu thap va phong chbng muoi khac.
Trong thuc te mot sb bien phap phdng chbng mudi mang tinh chat
tong hgp ciing dang dugc sir dung rdng rai nhu ve sinh mdi tmdng, khai
thdng cdng ranh, han che nai sinh san
ciia
muoi, phat quang
bin
ram quanh
nha, hun khdi diing huong xua diet mudi dimg binh xit cd hda chat diet
mudi Bien phap diet mudi bang cac load biy anh sang, sdng sieu toi ciing da
dugc ap dung.
1.
Bdy
anh sang. La loai bay diing ngudn anh sang vdi budc sdng thich
hgp de thu thap mudi Hien nay cd nhieu loai bdy anh sang dugc san xuat d
My, Canada, Phap, Nhat, Nga v.v
[i4].
-
Bfiy New
Jersey: Dung dien
ludi.
Tmdc

nam 1975 da dugc dung dat
cd dinh tai nhieu san bay d
Mien
Nam Viet nam de
tlieo
ddi
sir
giao luu cua
mudi bang dudng hang khdng.
- My
den CDC: Caay
biuig
acqui hoac pin, hien nay dang dugc diing
nhieu trong nghien cuu thu thap mudi
2.
Blv
am
dianh.
Do Ikesoji (1985) va
Kmda
(1988) phat
nmih,
Bily
la
mdt he thbng gbm cd chudt
lang,
CO2
va sdng sieu am
vdi
budc sdng

diich
22
hgp dugc phat ra tir mdt cai
loa.
Bky
dugc treo vao ban dem d do cao
1.5in
de
thu thap mudi Cd the dieu chinh budc sdng phu hgp de thu thap dugc nhieu
mudi
due
hay
mudi
cai
[14.75,79].
Thongmngkiat (1990) nghien
cini ling
dung biy am thanh de phdng
chdng Culex tritaeniorhyncus d Thai Lan da cho thay vdi tan sb am
thanli
530 Hz thu thap dugc sd lugng mudi cai nhien han ca (298 con mdt biy
trong mdt dem). Mudi due thu thap dugc
nhifeu
d tan sd 350 Hz (43 con mdt
bay, mdt dem)
[i
12,113].
(J Viet nam, chiing tdi chua thay cd tai
Ueu
nao cdng

bb ve viec nghien
ciiu
ling dung cac loai biy nay vdi muc dich han che mat
do quan the mudi chi thay
ling
dung biy den trong nghien
ciiu
dieu tra thu
thap thanh phan loai
3,
Ve sinh mdi
tnrdng.
Mdt trong nhiing bien phap phdng chdng mudi
cd hieu qua ciing da dugc cong nhan la ve sinh mdi tmdng; Thau rira cac
dung cu cd bg gay Aedes de phdng chdng sdt xuat huyet. Khai thdng cdng
ranh de phdng chdng mudi Culex: Phat quang bui ram xung quanh nha d de
han che mudi sdng gan nha. gan ngudi v.v
Qua qua trinh tham khao chiing tdi chua thay cd tai lieu nao ndi den
diet mudi bang mbi ba diet mudi
IL3.4.
Nhung cdng
trinh
nghien curu ve muoi va
nhihig
hda chat diet
muoi
chii
yeu da dugc su dung
d
Quang

Bmh.
Quang Binh lam cdng tac sdt ret tir nam 1961
den
nay. Ngay
tir iihirng
nam dau Vien sdt ret - Ky sinh trimg - Cdn trimg Ha noi da c6 nhung dieu tra
ca ban ve mudi trong tong the chung cua mien Bic. Cd the
kl
den mdt sd tac
gia da cd nhimg nghien
ciiu
lien quan den mudi d Quang Binh: Vii Thi Phan,