Table. Eastern equine encephalitis virus isolated and virus titers from mosquitoes obtained in Connecticut, USA, 2009*.
Mosquito species | No. mosquitoes collected | No. virus isolates | Infection rate/1,000 mosquitoes, MLE (95% CI) | Mean Ct by qRT-PCR | Mean titer log10 PFU/ mosquito pool | % Mosquito pools >3.0 log10 PFU/ mosquito pool |
---|---|---|---|---|---|---|
Aedes cinereus | 15,294 | 6 | 0.4 (0.2–0.8) | 34.0 | 2.92 | 16.7 |
Ae. vexans | 26,462 | 2 | 0.1 (0–0.2) | 33.0 | 1.15 | 0 |
Anopheles punctipennis | 5,573 | 4 | 0.7 (0.2–1.7) | 34.6 | 1.69 | 0 |
An. quadrimaculatus | 607 | 2 | 3.3 (0.6–10.6) | 35.9 | 1.67 | 0 |
An. walkeri | 2,381 | 2 | 0.8 (0.2–2.7) | 35.1 | 1.43 | 0 |
Culex restuans | 14,609 | 1 | 0.1 (0–0.3) | 35.2 | 0.85 | 0 |
Cx. salinarius | 12,605 | 3 | 0.2 (0.1–0.6) | 32.1 | 1.31 | 0 |
Culiseta melanura | 25,595 | 83 | 3.4 (2.8–4.2) | 22.3 | 6.55 | 88.0 |
Ochlerotatus canadensis | 40,543 | 10 | 0.2 (0.1–0.4) | 32.9 | 2.82 | 10.0 |
Oc. cantator | 4,457 | 1 | 0.2 (0–1.1) | 31.8 | 1.54 | 0 |
Oc. triseriatus | 3,000 | 1 | 0.3 (0–1.6) | >50 | 1.60 | 0 |
Oc. trivittatus | 23,340 | 2 | 0.1 (0–0.3) | 38.8 | <0.8 | 0 |
Psorophora ferox | 13,677 | 1 | 0.1 (0–0.35) | 34.0 | <0.8 | 0 |
Uranotaenia sapphirina | 2,954 | 4 | 1.4 (0.4–3.2) | 36.5 | 1.00 | 0 |
Remaining species† | 100,544 | 0 | – | – | – | – |
*MLE, maximum-likelihood estimation; CI, confidence interval; Ct, cycle threshold; qRT-PCR, quantitative reverse transcription–PCR; –, not applicable. Mean Ct and PFU values were calculated for mosquito pools positive by qRT-PCR and plaque titration. †n = 21.