Table 1. Transmission of HIV, Hepatitis B, Hepatitis C, and Prion Diseases.
| Author and year | Objective | Study design | Population size | Result | Quality score |
|---|---|---|---|---|---|
| Amin et al (2003) [13] | To determine the potential risk of horizontal transmission of proteinaceous material through the use of contact tonometry. How tested? | Experimental | 12 individuals | Tonometer tips can contribute to the transmission of proteinaceous material. Rinsing the tonometer tips in water reduced carryover of material. | 7/18 |
| Britt et al (1991) [16] | To determine whether human immunodeficiency virus (HIV) is dispersed through droplets during air puff tonometry. | Experimental | four individuals | One group received eye drops prior to the use of micro-aerosol tonometry, and one group did not. Scatter of eye droplets occurred in both groups during air puff tonometry. | 5/18 |
| Darrell and Jacob (1978) [17] | To determine the presence of hepatitis B in human tears and the risk of transferring this infection through contact lens fitting and contact tonometry. | Experimental | 33 individuals | Eighteen patients were tested with positive serum hepatitis B, and of these 18 individuals, 10 had hepatitis B in tears collected using the Schirmer strip or through the contact lens method. The 15 controls had no hepatitis B detected in their tears. | 5/18 |
| Feucht et al (1995) [18] | To determine whether the tear fluid of hepatitis C virus carriers is infectious. | Experimental | 76 individuals | All 76 patients chronically infected with hepatitis C were positive for hepatitis C RNA within tear fluid. | 6/18 |
| Komatsu et al (2012) [19] | To assess the possibility of transmission of hepatitis B virus in tears, urine, saliva and sweat. Additionally, the infectivity of tears from hepatitis B carriers was analyzed. | Experimental | 47 individuals | The transmissibility of this infectious disease from tears was studied in a chimeric mouse model. Hepatitis B tear specimens collected from a child and injected intravenously into two chimeric mice. One week following inoculation, both mice tested positive for hepatitis B DNA in their serum. | 11/18 |
| Moniz et al (1981) [20] | To determine whether tears contain hepatitis B surface antigen, to determine whether hepatitis B surface antigen can be detected on the tonometer tip following contact with carriers, and to determine whether washing the prism with running water is effective for removing hepatitis B surface antigen from contaminated tonometers. | Experimental | 31 individuals | Detection of hepatitis B surface antigen was only found in the conjunctival fluid of carriers who had higher titers of hepatitis B surface antigen in their sera. Rinsing the tonometer in water for ten seconds adequately removes detectable amounts of hepatitis B surface antigen from the tonometer. | 6/18 |
| Su et al (1994) [21] | To determine the transmissibility of hepatitis B DNA in human tears. | Experimental | 36 individuals | Detected that both patients with acute hepatitis B (two individuals) had tear specimens that were positive for HBV DNA, and 16 of the 34 carriers of chronic HBV had tear specimens that tested positive repeatedly for HBV DNA. The tear specimens of 10 of the 34 individuals with chronic HBV repeatedly tested negative, and the remaining eight tear specimens were equivocal. | 8/18 |
The table demonstrates the results regarding the transmissibility of HIV, hepatitis B, hepatitis C, and prion diseases through human tears.