Table 3. Coxiella burnetii investigation in abortion submissions by the different partners.
|
Reporting
Partner |
Histopathology | Bacteriology 1 | Serology | Real-time PCR |
|---|---|---|---|---|
| ANSES | S (ELISA) | VS; P; F; FSC 2 | ||
| APHA | P | P; FSC (MZN) | S 3 (ELISA) | P; FF 4 |
| FLI | P; F; FSC; VS; M
(culture) |
S; Pm; M (ELISA) | P; F; FSC; VS; M | |
| NEIKER | P; F 5 | P; F; VS (MZN) 6 | S (ELISA) | P; F; VS |
| Royal GD | P; F (including IHC 7 ) | S (ELISA) | VS 8 ; F; P (cattle) | |
| Sciensano | F | P; F (MZN) | S (ELISA) | F 9 ; P; VS; B |
B: maternal blood; BTM: bulk tank milk; F: fetus; FF: fetal fluid; FSC , fetal stomach contents; M: milk; P: placenta; Pm: plasma; S: maternal serum; VS: vaginal swab. IHC, immunohistochemistry; MZN, Modified Ziehl-Neelsen stain of smear; ELISA, enzyme-linked immunosorbent assay.
1 Bacteriology refers to MZN smears or culture isolation as stated.
2 For PCR, vaginal swabs are the preferred samples (essentially because they are optimal for preventing zoonotic transmission to the operators during shipment, storage, and analysis); when the test is performed on the placenta (collected in the uterus), a pool of three cotyledons is used; the test on the aborted fetus targets the spleen, liver, or stomach contents. Semi-quantitative PCRs (relative to a “clinical threshold”) or quantitative PCRs are performed.
3 Serology as ancillary test.
4 PCRs are performed when C. burnetii is detected or suspected (on MZN smears) and for all statutorily reported positive farms.
5 Fetal organs analysed are primarily liver and lung.
6 If placenta is not available, fetal (organ or stomach content) and/or vaginal swabs are analysed instead.
7 Immunohistochemistry is performed in case of placentitis.
8 Official protocol Dutch Food and Consumer Safety Authority in case of an increased number of abortions on small ruminant farms.
9 In the fetus, the abomasum, abomasum content, spleen, and liver are the preferred target, but all organs can be used. PCR is compulsory for small ruminants (part of the “Abortion protocol” funded by FASFC).