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A novel commercially available enzyme-linked immunosorbent assay (ELISA) for prevaccination screening and diagnosis of Q fever (PanBio Coxiella burnetii immunoglobulin G [IgG] ELISA) was compared to the complement fixation test (CFT), and the indirect fluorescent-antibody test (IFAT) was used to resolve discrepant results between the other two tests. A total of 214 serum samples was tested. The ELISA demonstrated a specificity of 96% (46 of 48 samples) and a sensitivity of 71% (95 of 134 samples). Of the six serum pairs showing CFT seroconversion, three pairs showed a corresponding ELISA seroconversion. No cross-reactivity was observed in the ELISA with serum samples from patients with mycoplasma, brucella, and chlamydia infections. One of the 13 patients with leptospirosis demonstrated a positive result in the ELISA but not in the CFT or the IFAT, and Legionella pneumophila serogroup 4 antibody was found in one of the two sera that were false-positive by ELISA. The results presented in this study suggest that the PanBio Q fever IgG ELISA is a specific alternative method for prevaccination testing and an aid for the diagnosis of Q fever. This test is suitable for use as a screening assay, with CFT and/or IFAT used to confirm negative results.

A conventional multiplex PCR assay that detects herpes simplex virus type 1 (HSV-1), HSV-2, varicella-zoster virus, and enteroviruses for the diagnosis of central nervous system infections was modified to be performed using the LightCycler system. The sensitivity of detection of each of the viruses using the LightCycler assay was compared to that of the conventional assay using external quality assessment material. The assays had equivalent sensitivities, but the LightCycler assay was more rapid, reduced the risk of contamination, and used an amplicon detection format that demonstrated greater discrimination than a gel electrophoresis method.

A commercially available enzyme-linked immunosorbent assay (ELISA) for the diagnosis of Q fever (PanBio Coxiella burnetii immunoglobulin M [IgM] ELISA, QFM-200) was compared to the indirect fluorescent antibody test (IFAT) for C. burnetii IgM and the complement fixation test (CFT). The ELISA demonstrated 92% agreement with the reference method (IFAT), and gave a sensitivity of 99% (69 of 70 samples) and a specificity of 88% (106 of 121). Specificity can be increased with confirmation by IFAT. CFT was found to have a specificity of 90% (107 of 119), although it was lacking in sensitivity (73%; 51 of 70). No cross-reactivity was observed in the ELISA with serum samples from patients with mycoplasma (n = 6), chlamydia (n = 5), or legionella (n = 4) infections, although 2 of 5 patients with leptospirosis and 1 of 4 samples containing rheumatoid factor (RF) demonstrated positive results in the ELISA. Results indicate that the performance of the PanBio C. burnetii (Q fever) IgM ELISA (F = 187) is superior to that of CFT (F = 163), and consequently the ELISA should be a useful aid in the diagnosis of acute Q fever.

During a 28-month period, 5,078 cultures from a variety of anatomical sites were received for staphylococcal phage typing. Of these, 503 (10%) were not suitable for the procedure requested. Of the 4,575 viable cultures, 1,030 (23%) of the microorganisms were nontypable at both the routine test dilution (RTD) and at 100 times RTD. Of the 3,545 typable organisms, 3,061 (86%) were lysed at RTD, whereas 484 (14%) were typed only at 100 times RTD. Observations pertaining to the typing efficacy of staphylococcal phage 94 indicate that 651 (18%) of the typable microorganisms were lysed only by phage 94 at RTD or at 100 times RTD. Without the addition of this new phage to the international basic set, the number of nontypable strains (1,030 or 23%) would have been 1,681 (39%). Data regarding the geographic distribution of Staphylococcus aureus phage 94 point to the occurrence of the host strain in 13 (68%) of 19 states and 18 (62%) of the 29 hospitals submitting specimens to this laboratory. The assumed origin and speculated mode of dissemination of this microorganism are discussed.

Haemophilus influenzae (H. aegyptius) biotype 3 was isolated from eye, nasopharyngeal, and sputum cultures of a 23-month-old male and from sputum and transtracheal aspirate cultures of his 39-year-old mother, both with diffuse bronchopneumonia.