Saliva and viral infections

Abstract

Over the last 10 years there have been only a handful of publications dealing with the oral virome, which is in contrast to the oral microbiome, an area that has seen considerable interest. Here, we survey viral infections in general and then focus on those viruses that are found in and/or are transmitted via the oral cavity; norovirus, rabies, human papillomavirus, Epstein-Barr virus, herpes simplex viruses, hepatitis C virus, and HIV. Increasingly, viral infections have been diagnosed using an oral sample (e.g. saliva mucosal transudate or an oral swab) instead of blood or urine. The results of two studies using a rapid and semi-quantitative lateral flow assay format demonstrating the correlation of HIV anti-IgG/sIgA detection with saliva and serum samples are presented. When immediate detection of infection is important, point-of-care devices that obtain a non-invasive sample from the oral cavity can be used to provide a first line diagnosis to assist in determining appropriate counselling and therapeutic path for an increasing number of diseases.

Figure 1

Consecutive flow assay format for detection of human anti‐HIV1/2 immunoglobulins. Antibodies indicated in red represent human anti‐HIV immunoglobulins in saliva that can bind to the HIV‐1/2 antigen Test line. Other IgG antibodies will bind to the flow Control line comprised of anti‐human IgG antibodies, located downstream of the Test line. Following a wash flow, the fluorescent reporter 30 that can bind to IgG on the Test and Control lines is flowed. The lateral flow strip is then scanned to record the presence of the reporter.

Figure 2

Detection of HIV antibody in serum and saliva. Relative amounts of HIV antibodies detected in paired serum and saliva samples. (A) Results obtained with the Woman's Interagency HIV Study sample set (n = 24); (B) results obtained with the National Institute of Dental and Craniofacial Research UO1 grant sample set (n = 38). The amounts of sample used in the test were 0.5 μl and 5 μl for serum and saliva, respectively. Samples were ranked by the Test/Flow Control ratio value determined with serum, with the HIV‐negative controls grouping together on the right side of the graph. RFU, Relative Fluorescent Units, is a measure the signal strength measured at the Test and Flow Control lines.