OBJECTIVE: To compare the effect of traditional conjunctival sac swab sampling (A) with aerosolization ocular surface microorganism sampling (B),a novel microbial sampling method, in detecting ocular microbial infection.
METHODS: The study included 61 participants (122 eyes) enrolled at the Eye Hospital, Wenzhou Medical University from December, 2021 to March, 2023. Each eye of the participants underwent sampling first with method A then B.Before aerosolization sampling, the air environment was disinfected and sampled as blank air control sample. Subsequently, the air pulses impinging the ocular surface causes dehiscence of the tear film covering the ocular surface and aerosols are formed.The microorganisms from the ocular surface attach to the aerosols generated as aerosolization ocular surface microorganism and be sampled as subject sample by bio-aerosol sampler.The samples were collected and incubated at 25℃ for 3-5 days and 37℃ for 24-48 h.The colonies were counted and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.
RESULTS: The accuracy in Group B was higher than that in Group A (45.8% vs. 38.3%, P = 0.289). There was a slight level of agreement between the results from both the sampling methods (k = 0.031, P = 0.730). The sensitivity in Group B was higher than that in Group A (57.1% vs. 35.7%, P = 0.453). The specificity results in Group B was higher than that in Group A (44.3% vs. 38.7%, P = 0.480). There were 12 and 37 types of microbes detected in Groups A and B, respectively.
CONCLUSIONS: Compared with traditional swab sampling, the novel aerosolization sampling method shows higher accuracy and more comprehensive detection of microbes; however, it cannot completely replace swab sampling. The novel method can be a novel conducive strategy and supplement swab sampling to auxiliary diagnose ocular surface infection.

OBJECTIVE: To compare the status of bacteria in the conjunctival sac from the elder Qiang minority and Han people with dry eyes in Sichuan, China.
METHODS: Total of 54 elder Qiang people with dry eyes (108 eyes) were examined by cluster sampling. In the similar habitation region of Han people, 80 (160 dry eyes) Han people were analyzed as the control group. The bacteria was separated from the inferior palpebral conjunctiva, then inoculated on blood plate for 48 hours and identified.
RESULTS: Totally 24 strains of bacteria were cultured in either Qiang minority or Han c populations with 3 strains of them existed in both ethnic groups. The commonest bacteria in conjunctival sac in two ethnic groups were non-pathogenic bacterium. The composition of Corynebacterium in Han people (54.1%) was significantly higher than that in Qiang minority (27.4%) (χ(2)=11.6721, P=0.0006). The percentage of Sphingomonas Paucimobilis in Qiang people was higher than that in Han people (χ(2)=18.6442, P=0.0000). However, there was no significant difference between Qiang minority and Han people either in bacterial positive rate in conjunctival sac, or the composition of bacteria species and strains, or the composition of staphylococcus epidemids between two ethnic populations.
CONCLUSIONS: There was no significant difference of bacterial positive rate in conjunctival sac from the elder of Qiang minority and Han people with dry eye, but the species of bacteria were different.