Background
Country (Reference) | Specimen origin | Number of ELISA positive specimens/Number of specimens tested | Number of specimens confirmed by PCR |
---|---|---|---|
Blood specimens tested* | |||
Thailand [15] | Cow blood | 12/16 | 0 |
Pig blood | 3/12 | 0 | |
Senegal [13] | Cow blood | 21/56 | 0 |
Mosquito head-thorax specimens tested
| |||
Gabon [37] | An. gambiae s.s. | ||
An. moucheti
| 28/1535 | 18 | |
An. funestus
| |||
South-Africa [12] |
An. demeilloni
| 44/unkown | 3 |
An. marshalli
| 6/unknown | 1 | |
An. rivulorum
| 4/unknown | 2 | |
South-Africa [14] |
An. parensis
| 20/149 | 0 |
Cameroon [36] | An. gambiae s.s. | ||
An. funestus
| 298/2773 | 263 | |
An. nili
|
Methods
Mosquito collection in Cambodia
Mosquito collection in Vietnam
Mosquito processing
CSP-ELISA
PCR detection of Plasmodium spp. or other parasites
DNA extraction
PCR
Cloning
PCR confirmation of previously analysed mosquitoes
Vector identification
Data analysis
Results
CSP-ELISA on head-thorax portions and confirmation by Plasmodium spp. specific PCR
Cambodia | Vietnam | |||||
---|---|---|---|---|---|---|
N° Tested | N° ELISA + | N° PCR confirmed | N° Tested | N° ELISA + | N° PCR confirmed | |
Anthropophilic
|
1144
|
12
|
11
|
864
|
12
|
8
|
An. dirus s.l. | 1144 | 12 | 11 1 | 864 | 12 | 8 1 |
Zoophilic trend
|
8089
|
104
|
0 (+1)*
|
6063
|
48
|
1
|
An. barbirostris
| 1628 | 33 | 0 (+ 1)* | na | na | na |
An. jamesii
| 17 | 1 | 0 | na | na | na |
An. maculatus s.l. | 3596 | 50 | 0 | 5081 | 42 | 0 |
An. minimus s.l. | 2848 | 20 | 0 | 530 | 4 | 1 2 |
An. pampanai
| na | na | na | 65 | 1 | 0 |
An. splendidus
| na | na | na | 387 | 1 | 0 |
Cambodia | Vietnam | |||||
---|---|---|---|---|---|---|
N° Tested | N° ELISA + | N° PCR confirmed | N° Tested | N° ELISA + | N° PCR confirmed | |
Anthropophilic
|
1144
|
5
|
4
|
864
|
4
|
4
|
An. dirus s.l. | 1144 | 5 | 4 1 | 864 | 4 | 4 1 |
Zoophilic
|
8089
|
2
|
1
|
6063
|
6
|
3
|
An. barbirostris
| 1628 | 1 | 0 | na | na | na |
An. jamesii
| 17 | 0 | 0 | na | na | na |
An. maculatus s.l. | 3596 | 0 | 0 | 5081 | 5 | 2 2 |
An. minimus s.l. | 2848 | 1 | 1 3 | 530 | 0 | 0 |
An. pampanai
| na | na | na | 65 | 1 | 1 4 |
An. splendidus
| na | na | na | 387 | 0 | 0 |
Village | Species | Number of mosquitoes positive by Plasmodium specific PCR/number of CSP-ELISA positive mosquitoes tested by PCR | |
---|---|---|---|
P. falciparum
|
P. vivax
| ||
Lang Nhot (Khanh Hoa) |
An. minimus
| 3/3 | 1/1 |
An. dirus
| 1/1 | 0 | |
Village 3 (Binh Thuan) |
An. dirus
| 2/3 * | 0 |
Cha Ong Chan (Rattanakiry) |
An. minimus
| 1/1 | 0 |
An. dirus
| 1/1 a | 0/1 a |
ELISA colour intensity score | ||||||
---|---|---|---|---|---|---|
Cambodia | Vietnam | |||||
1
|
2
|
3
|
1
|
2
|
3
| |
True positives
|
1
|
3
|
7
|
1
|
2
|
6
|
An. dirus s.l. | 1 | 3 | 7 | 1 | 2 | 5 |
An. minimus s.l. | 0 | 0 | 0 | 0 | 0 | 1 |
False positives
|
64
|
20
|
20
|
28
|
18
|
5
|
An. dirus s.l. | 1 | 0 | 0 | 4 | 0 | 0 |
An. barbirostris | 7 | 8 | 17 | na | na | na |
An. jamesii | 0 | 0 | 1 | na | na | na |
An. maculatus s.l. | 38 | 10 | 2 | 23 | 15 | 4 |
An. minimus s.l. | 18 | 2 | 0 | 1 | 2 | 0 |
An. pampanai | na | na | na | 0 | 1 | 0 |
An. splendidus | na | na | na | 0 | 0 | 1 |
Heat stability of the antigen causing the false positivity for the P. falciparum ELISA
PCR targeting other vector-transmitted parasites
CSP-ELISA on abdomens of positive specimens for the P. falciparum ELISA
Abdomens of P. falciparum ELISA true positive mosquitoes 1 | Abdomens of P. falciparum ELISA false positive mosquitoes 2 | |||||
---|---|---|---|---|---|---|
PCR + | PCR - | Total | PCR + | PCR - | Total | |
ELISA score 0 | 3 | 4 |
7
| 0 | 143 |
143
|
ELISA score 1 | 5 | 0 |
5
| 0 | 3 |
3
|
ELISA score 2 | 3 | 0 |
3
| 0 | 1 |
1
|
ELISA score 3 | 4 | 0 |
4
| 0 | 0 |
0
|
Total
|
15
|
4
|
19
|
0
|
147
|
147
|