Volume 17, Number 7—July 2011
Research
Co-infections of Plasmodium knowlesi, P. falciparum, and P. vivax among Humans and Anopheles dirus Mosquitoes, Southern Vietnam
Ron P. Marchand
, Richard Culleton, Yoshimasa Maeno, Nguyen Tuyen Quang, and Shusuke Nakazawa
, Richard Culleton, Yoshimasa Maeno, Nguyen Tuyen Quang, and Shusuke NakazawaTable
Frequencies of malaria parasite species determined by microscopy and PCR in 2 samples of human blood from residents of Khanh Phu commune, Vietnam, 2009–2010*
| Test categories |
Active case detection† |
Cross-sectional survey‡ |
|||||
| Men |
Women |
Total |
Men |
Women |
Total |
||
| No. tested | 110 | 64 | 174 | 25 | 12 | 37 | |
| Patient mean age, y |
25.7 |
25.1 |
25.5 |
20.7 |
20.0 |
20.4 |
|
| By microscopy determination | |||||||
| Total no. parasite positive | 47 (43) | 22 (34) | 69 (40) | 25 (100) | 12 (100) | 37 (100) | |
| No. Plasmodium falciparum positive | 38 (35) | 15 (23) | 53 (30) | 16 (64) | 4 (33) | 20 (54) | |
| No. P. vivax positive |
14 (13) |
8 (13) |
22 (13) |
13 (52) |
8 (67) |
21 (57) |
|
| By PCR determination | |||||||
| Total no. parasite positive | 60 (55) | 28 (44) | 88 (51) | 25 (100) | 12 (100) | 37 (100) | |
| No. P. falciparum positive | 49 (45) | 19 (30) | 68 (39) | 21 (84) | 6 (50) | 27 (73) | |
| No. P. vivax positive | 28 (25) | 14 (22) | 42 (24) | 18 (72) | 9 (75) | 27 (73) | |
| No. P. knowlesi positive | 8 (7) | 5 (8) | 13 (7) | 12 (48) | 7 (58) | 19 (51) | |
| No. P. malariae positive | 1 | 4 | 5 | 1 | 0 | 1 | |
| No. P. ovale positive |
0 |
0 |
0 |
0 |
0 |
0 |
|
| *Values are no. (%) except as indicated. All percentages are calculated over the total no. samples tested in each column. †The active case detection sample consisted of 174 blood samples of 549, including 69 of 121 found positive by microscopy. ‡In the cross-sectional survey, blood was taken from 624 persons, 49 of which were found positive by microscopy. A random selection of 37 blood samples of these 49 positive samples was analyzed by PCR. | |||||||
