Table 10

Specimen type

Document swab quality

Collect nasopharyngeal and oropharyngeal swabs from adults.

Swab material

Calcium alginate, rayon, Dacron or nylon swabs are acceptable for culture-based studies.

Swabs of inert material (e.g. nylon or Dacron) should be used for molecular methods.

Flocked swabs have many desirable characteristics.

Swab collection, transport and storage

1 ml STGG medium.

Freeze at −80°C as soon as possible, no ‘safe limit’ for 4°C storage, store at −20°C for days (not weeks).

Culture

10 µl of specimen, record if larger volume.

COBA and CNA plates acceptable alternatives to gentamicin-blood agar.

Recording semi-quantitative growth is optional

Selecting colonies

At least one α-haemolytic colony (representing the dominant morphology). If other colonies are tested, results should be analysed separately.

Identification

Real-time lytA is the current best molecular identification approach.

Optochin non-susceptible isolates should be tested for bile solubility.

Serotyping

‘Wet’ or ‘dry’ Quellung method is gold-standard.

Latex agglutination acceptable, other methods may be suitable.