Preparation:
 No eye drops, ointments or antiseptic solutions for at least 24 hours before collection (unless otherwise directed by the doctor). Contact lenses are not worn on the day of collection (ideally they should be removed at least 12–24 h before). No eye washes or washes on the day of collection (normal facial hygiene only). No local or systemic antibiotic treatment (if possible) 10–14 days before analysis – to avoid false negative results. If the treatment is ongoing, it is good to discuss with the doctor about the optimal time of collection.