Herpes Simplex Virus Type 1 Shedding in Tears and Nasal and Oral Mucosa of Healthy Adults

Abstract

Background: Herpes simplex virus type 1 (HSV-1) is prevalent worldwide and causes mucocutaneous infections of the oral area. We aimed to define the frequency and anatomic distribution of HSV-1 reactivation in the facial area in persons with a history of oral herpes.

Methods: Eight immunocompetent HSV-1 seropositive adults were evaluated for shedding of HSV-1 from 12 separate orofacial sites (8 from oral mucosa, 2 from nose, and 2 from conjunctiva) 5 days a week and from the oral cavity 7 days a week for approximately 5 consecutive weeks by a HSV DNA PCR assay. Symptoms and lesions were recorded by participants.

Results: Herpes simplex virus type 1 was detected at least from 1 site on 77 (26.5%) of 291 days. The most frequent site of shedding was the oral mucosa, with widespread shedding throughout the oral cavity. Lesional shedding rate was 36.4% (4 of 11 days with lesions), and the asymptomatic rate was 27.1% (65 of 240 nonlesional days). In individual participants, the median rate of HSV shedding by HSV PCR was 19.7% of days (range, 11%-63%).

Conclusions: Reactivation of HSV-1 on the oral mucosa is common and usually asymptomatic. However, HSV-1 is rarely found in tears and nasal mucosa. Frequent oral shedding of HSV-1 may increase the risk for transmitting the virus to both oral and genital mucosa of sexual partners.

Figure 1

Maximum HSV DNA (log₁₀ c/ml) detected per day, with presence or absence of lesions and symptoms for each participant. Participant 1 did not provide a diary.

Figure 2

Rate of HSV detection by PCR and viral culture in 8 participants with history of oral herpes. Of 269 PCR positive swabs, 73 (27.1%) swabs were both PCR and culture positive.

Figure 3A

Illustrative single participant depicting widespread shedding throughout the oral mucosa on days with viral reactivation. The number indicates the maximum HSV DNA (log₁₀ c/ml) detected at each facial site. Blank spaces indicated days without sampling.

Figure 3B

Illustrative single participant depicting several single site reactivation of HSV.