Table 2.
Seasonal abundance and natural nematode infections of female black flies collected at Ban Pang Dang, Doi Saket District, Chiang Mai province, northern Thailand, from March 2018 to January 2019.
| Season | Month | Simulium Species | No. Collected | No. Infected | No. Larva | % Infected | |||
|---|---|---|---|---|---|---|---|---|---|
| FL | NFL | UID | |||||||
| Hot | March | S. chumpornense | 2249 | 2616 | 0 | 0 | 0 | 0 | 0 |
| S. asakoae species-group | 363 | 0 | 0 | 0 | 0 | 0 | |||
| S. nigrogilvum | 3 | 0 | 0 | 0 | 0 | 0 | |||
| S. sp. | 1 | 1 | 1 L1 | 0 | 0 | 100 | |||
| June | S. asakoae species-group | 157 | 157 | 1 | 0 | 0 | 1 Mf | 0.64 | |
| Rainy * | September | S. asakoae species-group | 635 | 636 | 2 | 1 L3 | 1 L3 | 0 | 0.31 |
| S. striatum species-group | 1 | 0 | 0 | 0 | 0 | 0 | |||
| Dry-cool | November | S. asakoae species-group | 368 | 368 | 3 | 2 L3 | 1 L3 | 1 L1 | 0.82 |
| January | S. asakoae species-group | 807 | 820 | 2 | 1 L3 | 1 L3 | 0 | 0.25 | |
| S. striatum species-group | 8 | 0 | 0 | 0 | 0 | 0 | |||
| S. chamlongi | 2 | 0 | 0 | 0 | 0 | 0 | |||
| S. tani | 1 | 0 | 0 | 0 | 0 | 0 | |||
| S. bullatum | 1 | 0 | 0 | 0 | 0 | 0 | |||
| S. lampangense | 1 | 0 | 0 | 0 | 0 | 0 | |||
| Total | 4597 | 9 | 5 | 3 | 2 | - | |||
Abbreviations: Mf = microfilaria; L1 = first-stage larva; L3 = third-stage larva (infective larva); FL = filarial nematode; NFL = non-filarial nematode; UID = unidentified nematode; * black fly collections were conducted two times in this season.