Tình hình dịch bệnh sốt rét và các biện pháp khống chế ở Việt Nam Current situation and control operation of malaria in Viet Nam

CURRENT SITUATION AND CONTROL OPERATION OF MALARIA IN VIETNAM Dr.. SOME MAIN MALARIA DATABASE 2010-2012 OF VIETNAM report of NMCP Parasite... 2012 ACTIVITIES • Epidemiology - Detect

CURRENT SITUATION AND CONTROL OPERATION OF MALARIA

IN VIETNAM

Dr Vu Duc Chinh

Head Department of Entomology, National Institute of Malariology, Parasitology and Entomology, (NIMPE) Vietnam

SOME MAIN MALARIA DATABASE 2010-2012

OF VIETNAM (report of NMCP)

Parasite

2012 ACTIVITIES

• Epidemiology

- Detect malaria cases and parasites

- Confirm local or imported cases

- Monthly report to NMCP

- Training for health levels on malaria control & elimination program

• Treatment

- Instructions for proper treatment regimen

- Detect resistant parasite cases and study new regimen

- Training for local health levels on malaria treatment

• Entomology

- Residual spraying wall or bed net impregnation for high risk areas

- Distribute Long lasting nets for high transmission areas

- Detect insecticide resistance of malaria vectors

- Study new measures for vector control

- Training for local entomologists on mosquito identification & vector monitoring

MALARIA VECTOR MONITORING

OF NIMPE IN 2012

Monitor 16 of 53 Provinces in

whole country

Monitor 19 locations for

Impregnated bed nets

Monitor 13 locations for

Residual spraying wall

4

BIOASSAYS - SENSITIVITY TO INSECTICIDES

OF LOCAL ANOPHELES POPULATIONS (14 locations)

5

LOCATION (village, commune, district, province) Species Impregnated papers

Mortal ity (%)

Co Muông, Khổng Lào, Phong Thổ, Lai Châu An.philippinensis Lambdacyhalothrin 0,05% 98

Bản Xe, Mường Khiêng, Thuận Châu, Sơn La An.tesellatus Alphacypermethrin 30mg/m2 100

Nong Bon, Bó Mười, Thuận Châu, Sơn La An.philippinensis Lambdacyhalothrin 0,05% 100

Bản Sài, Nậm Sài, Sa Pa, Lào Cai An.kochi Alphacypermethrin 30mg/m2 100

Mường Bo, Thanh Phú, Sa Pa, Lào Cai An.kochi Lambdacyhalothrin 0,05% 100

Bản Chung, Yên Cường, Bắc Mê, Hà Giang An.philippinensis Alphacypermethrin 30mg/m2 99

Bản Noong, Lạc Nông, Bắc Mê, Hà Giang An.philippinensis Lambdacyhalothrin 0,05% 98

Xốp Thạng, Hữu Lập, Kỳ Sơn, Nghệ An An.philippinensis Lambdacyhalothrin 0,05% 100

Xốp Thạng, Hữu Lập, Kỳ Sơn, Nghệ An An.philippinensis Alphacypermethrin 30mg/m2 98

Na Chảo, Hữu Kiệm, Kỳ Sơn, Nghệ An An.kochi Lambdacyhalothrin 0,05% 98

Vùng Tròn, Sơn Kim, Hương Sơn, Hà Tĩnh An.philippinensis Alphacypermethrin 30mg/m2 100

Vùng Tròn, Sơn Kim, Hương Sơn, Hà Tĩnh An.philippinensis Lambdacyhalothrin 0,05% 100

Khe Chẹt, Sơn Kim, Hương Sơn, Hà Tĩnh An.philippinensis Alphacypermethrin 30mg/m2 100

Khe Chẹt, Sơn Kim, Hương Sơn, Hà Tĩnh An.philippinensis Lambdacyhalothrin 0,05% 100

RESIDUAL EFFECT OF TREATED SURFACE (1)

6

Province Species Surface Insecticides After

treatment (days)

Mosquito mortality (%)

Lai Châu An.philippinensis Wood Fendona 10SC 200 20

An.philippinensis Nets ICON 2,5CS 204 82 Sơn La An.tessellatus Wood Fendona 10SC 136 43

An.philippinensis Nets ICON 2,5CS 165 68 Lào Cai An.kochi Wood Fendona 10SC 178 55

An.philippinensis Nets ICON 2,5CS 180 62

Hà Giang An.philippinensis Bamboo Fendona 10SC 146 63

An.philippinensis Nets ICON 2,5CS 140 83 Tuyên

Quang

An.philippinensis Nets ICON 2,5CS 40 81

An.kochi Wood Fendona 10SC 33 39

Cao Bằng An.philippinensis Nets ICON 2,5CS 170 72

An.kochi Nets ICON 2,5CS 173 52

Ninh Bình An tessellatus Nets ICON 2,5CS 62 95

An.minimus Nets ICON 2,5CS 65 100 Nghệ An An.philippinensis Nets ICON 2,5CS 210 48

An.kochi Nets ICON 2,5CS 215 99

RESIDUAL EFFECT OF TREATED SURFACE (2)

7

Province Species Surface Insecticides After

treatment (days)

Mosquito mortality (%)

Hà Tĩnh An.philippinensis Nets ICON 2,5CS 170 72

An.kochi Nets ICON 2,5CS 173 52

Quảng

Bình

An annularis Wood Fendona 10SC 103 25

An.annularis Nets ICON 2,5CS 127 78

Quảng Trị An.tessellatus Wood Fendona 10SC 136 43

An.philippinensis Nets ICON 2,5CS 165 68

Bình Định An.kochi Brick Fendona 10SC 119 38

An.philippinensis Nets ICON 2,5CS 15 62

Đăk Lăk An.pediteaniatus Wood Fendona 10SC 136 16

An.philippinensis Nets ICON 2,5CS 138 13

Đăk Nông An.aconitus Nets ICON 2,5CS 30 98

An.aconitus Wood Fendona 10SC 23 92 Đồng

Tháp

An.sinensis Nets ICON 2,5CS 36 10

An sinensis Nets ICON 2,5CS 38 15

An Giang An vagus Nets ICON 2,5CS 110 61

An vagus Nets ICON 2,5CS 110 23

BIOASSAYS - SENSITIVITY TO INSECTICIDES OF ANOPHELES

AN.MINIMUS IN SENTINEL SITE OF BẮC KẠN PROVINCE

8

INSECTICIDE

IMPREGNATED

PAPER

5/2011 Mortality (%)

10/2011 Mortality (%)

5/2012 Mortality (%)

11/2012 Mortality (%)

1

Lambdacyhalo-thrin 0,05% 99 100 97 100

2

Alphacyperme-thrin 30mg/m2 99 98 97 100

3 Deltamethrin

-4 Permethrin

0,75% 99 100 97 100

5 Etofenprox

0,5% 100 99 - -

-LLIN TRIAL IN LARGE SCALE (Phase III)

9

Nets type

CTN (delta-methrin 25mg/m2

Permanet 2.0

(vestergaard) Permanet 3.0

(vestergaard) Percentage of individuals that declared

one or several adverse (in first week) % 13 17 14

Percentage of individuals that declared

one or several adverse (in first year) % 18 31 41

Percentage of nets left in household after

Percentage of nets is using in

Percentage of nets with holes after 1

Mortality of An.dirus in bioassays after 1

Percentage of nets has been washed at

SMALL-SCALE EVALUATION OF THE EFFICACY AND RESIDUAL ACTIVITY

OF INSECTICIDES (1)

Insecticide and dose

Motality (%) after 1 week treatment

Motality (%) after 1 month treatment

Motality (%) after 2 month treatment

Pyrimiphos-Methyl 30%CS dose 1g/m2 100 28 16

Pyrimiphos-Methyl 500EC dose 1g/m2 100 84 69

Chlorfenapyr 24%SC dose 250mg/m2 14 13 -

Chlorfenapyr 24%SC dose 150mg/m2 19 17 -

Deltamethrin 25%WDG dose 15mg/m2 43 18 55

Deltamethrin 62.5 SC dose 15mg/m2 18 13 16

Deltamethrin 62.5 SC dose 20mg/m2 22 3 26

Deltamethrin 62.5 SC dose 25mg/m2 22 4 23

ON WOODEN WALL:

Residual effect less than < 1 month (Low mortality of An.dirus)

SMALL-SCALE EVALUATION OF THE EFFICACY AND RESIDUAL ACTIVITY

OF INSECTICIDES (2)

Insecticide and dose

Motality (%) after 1 week treatment

Motality (%) after 1

month treatment

Motality (%) after 2

month treatment

Motality (%) after3mont

h treatment

Pyrimiphos-Methyl 30%CS dose 1g/m2 84 14 11 -

Pyrimiphos-Methyl 500EC dose 1g/m2 89 17 13 -

Chlorfenapyr 24%SC dose 250mg/m2 10 13 - -

Chlorfenapyr 24%SC dose 150mg/m2 6 18 - -

Deltamethrin 25%WDG dose

15mg/m2 100 96 94 62

Deltamethrin 62.5 SC dose 15mg/m2 99 89 93 92

Deltamethrin 62.5 SC dose 20mg/m2 98 81 88 53

Deltamethrin 62.5 SC dose 25mg/m2 100 96 97 71

ON BRICK WALL:

Residual effect less than < 4 month (Low mortality of An.dirus)

Forest

Fringe forest

Village

ENTOMOLOGICAL SURVEY IN BÌNH PHƯỚC PROVINCE, WHERE PRESENT OUTDOOR MALARIA VECTORS AND ARTEMICININ RESISTANT PARASITE

In the village

+ Residual Insecticide

spraying wall in the village + Bed net impregnation + LLIN distribution

Low density of An.dirus, An.minimus,

An.maculatus

Plot hut in fringe forest where catched An.dirus, An.minimus, An.maculatus

In forest

Where catched:

An dirus, An minimus

but not An maculatus

WHERE IS DANGEROUS?

in Village, Fringe forest or Deep forest?

COMMUNE SPECIES

Number of mosquito collected by human landing & Percentage between landscape areas(%)

In the village In fringe forest

(cultivation area)

In the forest

Dăk Ơ:

An.maculatus 4 (50%) 4 (50%) 0 (0%)

Dăk Nhau:

An.maculatus 4 (21%) 15 (79%) 0 (0%)

(1.4%)

293 (20.6%)

1108 (77.9%)

What species actually transmit malaria?

(Lies Durnez et all, 2011)

An dirus must be the most important malaria vector

What species is the most important?

An dirus: Positive, and high density

An minimus: Positive, but few in the study area

An maculatus : negative

How to protect people

- Residual spraying wall: low effect, only

use in the village but cannot apply for

fringe forest and forest

bring to forest but can not protected

people before go to bed

- Repellence? Need to approach to protect

people of early biting?