Table 5.
Serological and quantitative polymerase chain reaction (qPCR) assay results from goat and environmental samples collected during an outbreak of Q fever in Victoria, 2013–2014
| Complement fixation test titres (IgM or IgG, C. burnetii Phase II specific) | qPCR assay for C. burnetii | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Age, years | Cycle threshold (Ct) | ||||||||||||
| Titre | <2 | 2–4 | ⩾5 | Unknown | Sample type | No. of samples | Positive | <20 | 20–30 | 30–35 | >35 | Inconc. | Negative |
| 8 | 0 | 1 | 1 | 0 | Goat vaginal swab | 15 | 4 | 2 | 1 | 1 | − | 11 | |
| 16 | 3 | 2 | 0 | 0 | Placenta | 9 | 6 | 3 | − | 1 | 2 | − | 3 |
| 32 | 0 | 1 | 0 | 0 | Aborted kids | 22 | 18 | 3* | 5 | 6 | 4 | − | 4 |
| 64 | 0 | 0 | 0 | 0 | Live kid | 2 | − | − | − | − | − | − | 2 |
| 128 | 0 | 1 | 0 | 0 | Air sample (500 l) | 3 | − | − | − | − | − | 1 | 2 |
| Negative | 28 | 17 | 4 | 1 | Goat faeces | 1 | − | − | − | − | − | − | 1 |
| Inconc. | 3 | 3 | 0 | 0 | Bedding | 3 | − | − | − | − | − | 1 | 2 |
| Apparent prevalence | 9·7% | 22·7% | 20·0% | – | |||||||||
*
One sample, Ct = 11·94, culture obtained from this specimen.
Inconc., Inconclusive results. For qPCR, only one target present or a single target present in only one of duplicate reactions.