Rubella Virus-Associated Cutaneous Granulomatous Disease: a Unique Complication in Immune-Deficient Patients, Not Limited to DNA Repair Disorders.

The association of immunodeficiency-related vaccine-derived rubella virus (iVDRV) with cutaneous and visceral granulomatous disease has been reported in patients with primary immunodeficiency disorders (PIDs). The majority of these PID patients with rubella-positive granulomas had DNA repair disorders. To support this line of inquiry, we provide additional descriptive data on seven previously reported patients with Nijmegen breakage syndrome (NBS) (n = 3) and ataxia telangiectasia (AT) (n = 4) as well as eight previously unreported patients with iVDRV-induced cutaneous granulomas and DNA repair disorders including NBS (n = 1), AT (n = 5), DNA ligase 4 deficiency (n = 1), and Artemis deficiency (n = 1). We also provide descriptive data on several previously unreported PID patients with iVDRV-induced cutaneous granulomas including cartilage hair hypoplasia (n = 1), warts, hypogammaglobulinemia, immunodeficiency, myelokathexis (WHIM) syndrome (n = 1), MHC class II deficiency (n = 1), Coronin-1A deficiency (n = 1), X-linked severe combined immunodeficiency (X-SCID) (n = 1), and combined immunodeficiency without a molecular diagnosis (n = 1). At the time of this report, the median age of the patients with skin granulomas and DNA repair disorders was 9 years (range 3-18). Cutaneous granulomas have been documented in all, while visceral granulomas were observed in six cases (40%). All patients had received rubella virus vaccine. The median duration of time elapsed from vaccination to the development of cutaneous granulomas was 48 months (range 2-152). Hematopoietic cell transplantation was reported to result in scarring resolution of cutaneous granulomas in two patients with NBS, one patient with AT, one patient with Artemis deficiency, one patient with DNA Ligase 4 deficiency, one patient with MHC class II deficiency, and one patient with combined immunodeficiency without a known molecular etiology. Of the previously reported and unreported cases, the majority share the diagnosis of a DNA repair disorder. Analysis of additional patients with this complication may clarify determinants of rubella pathogenesis, identify specific immune defects resulting in chronic infection, and may lead to defect-specific therapies.

Natural history of polyomaviruses in men: the HPV infection in men (HIM) study.

BACKGROUND: Several new polyomaviruses have been discovered in the last decade, including Merkel cell polyomavirus (MCPyV). Little is known about the natural history of the more recently discovered polyomaviruses. We estimated the incidence, prevalence, and persistence of 9 polyomaviruses (MCPyV, BK polyomavirus, KI polyomavirus, JC polyomavirus, WU polyomavirus, Human polyomavirus 6 [HPyV6], HPyV7, HPyV9, and Trichodysplasia spinulosa-associated polyomavirus) and examined factors associated with MCPyV infection in a prospective cohort of 209 men initially enrolled in the HPV Infection in Men (HIM) study. METHODS: Participants enrolled at the US site of the HIM study were recruited into a substudy of cutaneous viral infections and followed for a median of 12.6 months. Eyebrow hair and normal skin swab specimens were obtained at each study visit, and the viral DNA load was measured using multiplex polymerase chain reaction. RESULTS: MCPyV infection showed the highest prevalence (65.1% of normal skin swab specimens and 30.6% of eyebrow hair specimens), incidence (81.7 cases per 1000 person-months among normal skin swab specimens, and 24.1 cases per 1000 person-months among eyebrow hair specimens), and persistence (85.8% of normal skin swab specimens and 58.9% of eyebrow hair specimens) among all polyomaviruses examined. Age of >44 years (odds ratio [OR], 2.11; 95% confidence interval [CI], 1.03-4.33) and Hispanic race (OR, 2.64; 95% CI, 1.01-6.88) were associated with an increased prevalence of MCPyV infection in eyebrow hair and normal skin swab specimens, respectively. CONCLUSION: MCPyV infection is highly prevalent in adults, with age and race being predisposing factors.

α- and ß-papillomavirus infection in a young patient with an unclassified primary T-cell immunodeficiency and multiple mucosal and cutaneous lesions.

BACKGROUND: Correlating human papillomavirus (HPV) type with the clinical and histopathological features of skin lesions (from genital and nongenital sites) can present a diagnostic challenge. OBJECTIVE: In this study, HPV infection patterns were correlated with pathology and clinical presentation in lesional and nonlesional body sites from a young patient with a primary T-cell immunodeficiency. METHODS: HPV infection was evaluated at both DNA and protein levels by polymerase chain reaction and immunohistochemistry. RESULTS: The patient's genital lesions were caused exclusively by α-genotypes (high-risk type HPV-51 in the anal and low-risk type HPV-72 in the penile condylomas). The opposite was true for the skin lesions, which were infected by ß-genotypes alone (HPV-8 and HPV-24). HPV-24 was the predominant type in terms of viral load, and the only one found in productive areas of infection. The patient had already developed high-grade dysplasia in the anal condyloma-like lesions, and showed areas of early-stage dysplasia in the lesions caused by the ß-genotype HPV-24. LIMITATIONS: The basic origin of the immunodeficiency is not yet defined. CONCLUSION: These findings provide proof of principle that both α- and ß-genotypes can cause overt dysplastic lesions when immunosurveillance is lost, which is not restricted to epidermodysplasia verruciformis.

Characterization of human papillomavirus type 120: a novel betapapillomavirus with tropism for multiple anatomical niches.

Recent studies indicate that human papillomaviruses (HPVs) from the genera Betapapillomavirus and Gammapapillomavirus are abundant in the human oral cavity. We report the cloning and characterization of a 7304 bp HPV120 genome from the oral cavity that is related most closely to HPV23 (L1 ORF, 83.7 % similarity), clustering it in the genus Betapapillomavirus (ß-PV). HPV120 contains five early and two late genes, but no E5 ORF. HPV120 was detected from heterogeneous human biological niches, including the oral cavity, eyebrow hairs, anal canal and penile, vulvar and perianal warts. Characterization of the clinical spectrum of HPV120 infections indicates a broader spectrum of epithelial tropism than appreciated previously for HPV types from the genus ß-PV.

Do Dogs and Cats Passively Carry SARS-CoV-2 on Hair and Pads?

The epidemiological role of domestic animals in the spread and transmission of SARS-CoV-2 to humans has been investigated in recent reports, but some aspects need to be further clarified. To date, only in rare cases have dogs and cats living with COVID-19 patients been found to harbour SARS-CoV-2, with no evidence of pet-to-human transmission. The aim of the present study was to verify whether dogs and cats act as passive mechanical carriers of SARS-CoV-2 when they live in close contact with COVID-19 patients. Cutaneous and interdigital swabs collected from 48 dogs and 15 cats owned by COVID-19 patients were tested for SARS-CoV-2 by qRT-PCR. The time elapsed between owner swab positivity and sample collection from pets ranged from 1 to 72 days, with a median time of 23 days for dogs and 39 days for cats. All samples tested negative, suggesting that pets do not passively carry SARS-CoV-2 on their hair and pads, and thus they likely do not play an important role in the virus transmission to humans. This data may contribute to confirming that the direct contact with the hair and pads of pets does not represent a route for the transmission of SARS-CoV-2.

Patient Recovery from COVID-19 Infections: Follow-Up of Hair, Nail, and Cutaneous Manifestations.

BACKGROUND: COVID-19 is a pandemic disease worldwide. Although cutaneous manifestations may present in affected patients, there have been limited studies on the cutaneous findings and hair and nail abnormalities after discharge. OBJECTIVE: To establish the cutaneous manifestations, hair and scalp disorders, and nail abnormalities in patients who recovered from COVID-19 infections. METHODS: A retrospective chart review and telephone interviews were conducted to determine the cutaneous manifestations, hair and scalp disorders, and nail abnormalities of patients aged over 18 years who were diagnosed with COVID-19 infections at Siriraj Hospital, Bangkok, Thailand, between January and June 2020. RESULTS: Ninety-three patients with prior COVID-19 infections participated in the study. The COVID-19 severity had been mild for most (71%). Cutaneous manifestations were reported in 8 patients (8.6%), with the common skin conditions being maculopapular rash and urticaria. The onsets of the skin conditions were before admission (1%), during admission (4.3%), and after discharge (3.2%). Increased hair shedding was also reported in 22 patients (23.7%), with a female predominance. Three patients were affected during admission, while the others were affected after discharge. The patients with moderate, severe, and critical COVID-19 infections experienced significantly more hair shedding than those with asymptomatic and mild diseases. Only 2 patients with mild COVID-19 disease reported nail abnormalities (chromonychia and brittle nails). CONCLUSIONS: Cutaneous manifestations, hair disorders, and nail abnormalities can occur in patients with COVID-19 after their discharge from hospital. Patients should therefore be followed up in anticipation of dermatological problems.

Betapapillomavirus infection profiles in tissue sets from cutaneous squamous cell-carcinoma patients.

Human papillomaviruses from the genus beta (betaPV) are a possible cause of cutaneous squamous cell carcinoma (SCC). We compared the betaPV infections in SCC and in sets of cutaneous tissues collected from a series of individual SCC patients to determine concordance and to assess the adequacy of eyebrow hairs as noninvasive markers of betaPV infection. Biopsies of SCC tumors, perilesional tissue, normal skin from the mirror image of nonfacial SCC and plucked eyebrow hairs were collected from 21 patients with incident SCC living in Queensland, Australia. These were tested for the presence of DNA from 25 different betaPV types. Overall prevalence of betaPV was high in every sample type, ranging from 81% to 95%. The median number of types was significantly higher in the SCC tumour (6), perilesional skin (5) and eyebrow hairs (5) than in normal skin (2). Comparing SCC tissue with other sample types within patients showed 63 overlapping infections with eyebrow hairs (71%; 95% CI: 60-80); 56 with perilesional skin samples (63%; 95% CI: 52-73) and 23 with normal skin samples (26%; 95% CI: 17-36). The sensitivity of eyebrow hair testing for detection of betaPV in the tumor was 82% (95% CI: 57-96) with concordance defined as 50% of betaPV types in common and 29% (95% CI: 10-56) for 100% concordance. These findings support the concept that perilesional skin represents an area of field change involving betaPV preceding SCC development and indicate that eyebrow hairs can serve to some degree as an easily collected marker of tumor betaPV status in epidemiological studies.

Cottontail rabbit papillomavirus in Langerhans cells in Sylvilagus spp.

A wildlife sanctuary presented an adult female cottontail rabbit (Sylvilagus spp.), age unknown, to the Colorado State University Pathology service for postmortem examination. Gross examination revealed numerous pigmented wartlike lesions arising from the skin of the head surrounding the ears, eyes, nares, mouth, and dorsum. Masses were firm, friable, and easily detached from the underlying skin. Differential diagnoses included Cottontail rabbit papillomavirus, Rabbit fibroma virus, and Myxoma virus. Histological examination revealed multiple papillary masses lined by stratified squamous epithelial cells with central cores of fibrovascular connective tissue and parakeratotic hyperkeratosis. Cells of the Stratum spinosum were frequently swollen with abundant perinuclear, cytoplasmic, clearing, and occasional intranuclear basophilic, glassy, spherical inclusions up to 3 microm in diameter. The lesions were consistent with Cottontail rabbit papillomavirus infection. Papilloma virus antigens were identified by immunohistochemistry. In addition, papillomavirus particles were identified by transmission electron microscopy within Langerhans cells of the epidermis, suggesting a unique mechanism for systemic dissemination of the virus. The present case report highlights the finding of viral particles within the Langerhans cells and suggests a novel mechanism of pathogenesis.

Development and validation of a portable, point-of-care canine distemper virus qPCR test.

Canine distemper virus (CDV) is a multi-host pathogen that can cause significant mortality in domestic, wild terrestrial and marine mammals. It is a major conservation threat in some endangered species. Infection can result in severe respiratory disease and fatal encephalitis. Diagnosis and disease monitoring in wildlife, and differentiation of CDV from rabies (a life-threatening zoonotic disease that can produce similar neurologic signs), would benefit from the availability of a portable, point-of-care (POC) diagnostic test. We therefore developed a quantitative RT-PCR assay for CDV using shelf-stable, lyophilized reagents and target-specific primers and probes for use with the handheld Biomeme two3™ qPCR thermocycler. Biomeme's extraction methodology, lyophilized reagents, and thermocycler were compared to our standard laboratory-based methods to assess sensitivity, efficiency and overall test performance. Results using a positive control plasmid for CDV showed comparable sensitivity (detection of 50 copies) and PCR efficiency between the two platforms, and CDV detection was similar between platforms when tested using a modified live CDV vaccine. Significantly higher Ct values (average Ct = 5.1 cycles) were observed using the Biomeme platform on known CDV positive animal samples. CDV detection using the Biomeme platform was similar in 25 of 26 samples from suspect CDV cases when compared to standard virology laboratory testing. One false positive was observed that was negative upon retest. The Biomeme methodology can be adapted for detection of specific targets, and this portable technology saves time by eliminating the need for local or international sample transport for laboratory-based diagnostics. However, results of our testing suggest that decreased diagnostic sensitivity (higher Ct values) relative to laboratory-based methods was observed using animal samples, so careful validation and optimization are essential. Portable qPCR platforms can empower biologists and wildlife health professionals in remote and low-resource settings, which will greatly improve our understanding of CDV disease ecology and associated conservation threats in wildlife.

Development and evaluation of real-time RT-PCR using ear hair for specific detection of sheep persistently infected with border disease virus (BDV).

The aim of this study was to develop an improved border disease virus (BDV) specific real time RT-PCR and to evaluate its performance on manually plucked hairs from sheep persistently infected with BDV that may act as a non-invasive alternate sample. The BDV real time RT-PCR assay reported here showed a high analytical sensitivity (100.6 TCID50/ml), specificity (no reactivity with BVDV-1, BVDV-2, HoBi-like pestivirus and CSFV) and reproducibility. When the assay was validated on 210 samples from BDV-infected and uninfected sheep, it showed a 100% diagnostic sensitivity and specificity with virus isolation. Further evaluation of the assay on manually plucked hair follicles from ear (mid-lateral, mid-medial) and tail tip from sheep persistently infected with BDV showed that a minimum of 20 hair follicles need to be tested for correct diagnosis of BDV. The BDV load was comparatively higher in hairs from mid-medial ear than those from other tested locations. Evaluation on other samples from PI sheep demonstrated that the test performance was similar to that of pestivirus generic real-time RT-PCR, but improved than the currently available BDV specific real-time RT-PCR. Although more number of PI animals need to be evaluated, the results of the study showed that manually plucked hairs from mid-medial ear pinna is a suitable alternative sample in real-time RT-PCR for detection of BDV persistently infected sheep. Use of the non-invasive ear hair samples and the improved BDV specific real-time RT-PCR reported here may be useful for BDV surveillance in several sheep rearing countries.

Gynecologic assessment of 19 adult females with cartilage-hair hypoplasia - high rate of HPV positivity.

BACKGROUND: Patients with cartilage-hair hypoplasia (CHH), a rare metaphyseal chondrodysplasia, manifest severe growth failure, variable immunodeficiency and increased risk of malignancies. The impact of CHH on gynecologic and reproductive health is unknown. Vulnerability to genital infections may predispose CHH patients to prolonged human papillomavirus (HPV) infections potentially leading to cervical, vaginal and vulvar cancer. METHODS: We carried out gynecologic evaluation, pelvic ultrasound and laboratory assessment in 19 women with genetically confirmed CHH. All patients were clinically examined and retrospective data were collected from hospital records. RESULTS: The women ranged in age from 19.2 to 70.8 years (median 40.8 years) and in height from 103 to 150 cm (median 123 cm). All women had undergone normal pubertal development as assessed by breast development according to Tanner scale and by age of menarche (mean 12.5 yrs., range 11-14 yrs). Despite significant short stature and potentially small pelvic diameters, a well-developed uterus with fairly normal size and shape was found by pelvic ultrasound in most of the patients. Ovarian follicle reserve, assessed by ultrasound was normal in relation to age in all premenopausal women it could be assessed (12 cases). Anti-Müllerian hormone was normal in relation to age in 17 women (89%). HPV was detected in 44% (8/18) and three women carried more than one HPV serotype; findings did not associate with immunological parameters. Three patients had a concurrent cell atypia in Pap smear. CONCLUSIONS: Pubertal development, reproductive hormones and ovarian structure and function were usually normal in women with CHH suggesting fairly normal reproductive health. However, the immunodeficiency characteristic to CHH may predispose the patients to HPV infections. High prevalence of HPV infections detected in this series highlights the importance of careful gynecologic follow up of these patients.

Molecular characterization of the porcine endogenous retrovirus subclass A and B envelope gene from pigs.

Xenotransplantation of porcine organs has the potential to overcome the current critical shortage of allogenic organs for transplantation in humans. However, the existence of porcine endogenous retroviruses (PERVs) presents a problem for the clinical use of xenografts from pigs. In an attempt to understand the molecular characteristics of PERVs, we cloned the PERV env gene from six pig breeds (ie, Berkshire, Duroc, Landrace, Yorkshire, and two types of miniature pigs) in Korea. A total of 141 env clones were isolated and their sequences were analyzed. Phylogenetic analyses of these genes revealed the presence of PERVs, from both classes A and B, in 54% and 46% of the env clones, respectively. Among these clones, 37 isolates had the correct open reading frame (ORF; 27 clones in subclass A and 10 clones in subclass B), while the others had premature termination. These PERV nucleotide sequences can be used in a database for comparisons of PERV distribution among different pig breeds and for monitoring PERV infection using isolates with functional ORFs. Recombinant envelope of subclass A and B with functional ORF was expressed by vaccinia virus systems. Additionally isolated env clones can be used for various experiments, such as PERV control and infectivity tests, and may enhance the understanding of molecular mechanisms through pseudotyped PERV viruses.

HPV DNA detection and typing in inapparent cutaneous infections and premalignant lesions.

Epidemiological studies, which address the role of human papillomavirus (HPV) in the pathogenesis of (pre)malignant cutaneous lesions, focus on the HPV B1 subgroup comprising the so-called epidermodysplasia verruciformis (EV)-associated HPV types. To detect and type HPV DNA in human materials, Polymerase Chain Reaction (PCR)-based assays are used. In this chapter, a nested, broad-spectrum PCR method using a mixture of primers and a type-specific PCR using specific primers are described. The broad-spectrum PCR detects the B1 subgroup of HPV types. HPV typing is performed by sequence analysis of the PCR product. The type-specific PCR detects and types HPV 5a, 8, 15, 17, 20, 24, 36, and 38. These HPV types are representative of the B1 subgroup, because they are evenly distributed over the phylogenetic tree of the B1 subgroup.

Detection of human papillomavirus DNA in plucked hairs from renal transplant recipients and healthy volunteers.

We have previously detected a group of human papillomaviruses originally found in skin lesions of epidermodysplasia verruciformis (EV) patients in skin cancers from renal transplant recipients and from non-immunosuppressed patients. The reservoir of EV-HPVs is still unknown. In the current study we investigated whether EV-HPV DNA can be detected in plucked hairs from renal transplant recipients and healthy volunteers. Hairs were plucked from eyebrows, scalp, arms, and/or legs and DNA was subsequently isolated. To detect EV-HPV, we used nested PCR with degenerate primers located in the HPV L1 open reading frame. HPV DNA was detected in hairs from one or more sites in all 26 renal transplant recipients tested. Forty-five of 49 samples (92%) from these 26 patients were positive. The HPV type was successfully determined by sequencing in 38 samples, and all types belonged to the EV-HPVs. In ten of 22 healthy volunteers (45%), EV-HPV DNA was also detected in hairs from one or more sites. Twenty of 38 samples (53%) were positive, of which 17 samples were typed as EV-HPV types. These findings indicate that EV-HPV is subclinically present in the skin of the general population. Immunosuppression may lead to activation of the virus, explaining the finding that the apparent prevalence of EV-HPV in plucked hairs from renal transplant patients is higher than in those from the volunteers. If a dose-response situation exists for the carcinogenic potential of HPV infection, this finding may be relevant to the increased risk of skin cancer in this group of patients.

Increased prevalence of human papillomavirus in hairs plucked from patients with psoriasis treated with psoralen-UV-A.

BACKGROUND: Patients with psoriasis treated with psoralen-UV-A (PUVA) are at increased risk of skin cancer; however, the exact causes of this increased incidence are not well understood. It has been suggested that PUVA may increase expression of the tumorigenic agent human papillomavirus (HPV) in skin by directly stimulating virus replication, immune suppression, or both, thereby leading to skin cancer formation. OBJECTIVE: To determine whether HPV DNA prevalence in the skin is increased after long-term PUVA treatment. DESIGN: Screening for the presence of HPV sequences in DNA isolated from plucked body hairs of patients with psoriasis with a history of PUVA exposure and a history of skin cancer (group A), PUVA exposure and no history of skin cancer (group B), and no PUVA exposure and no history of skin cancer (group C). SETTING: University hospital. PATIENTS AND METHODS: Hair samples were obtained from 81 patients with psoriasis (56 men and 25 women; mean age, 52 years), including 16 in group A (mean number of PUVA exposures, 702), 35 in group B (mean number of PUVA exposures, 282), and 30 in group C. DNA was isolated from the hair samples and analyzed by polymerase chain reaction with the use of 2 nested primer systems specific for epidermodysplasia verruciformis-associated or related and genital or mucosal virus types, respectively. RESULTS: The rate of HPV DNA positivity was significantly higher in groups A (73% [11/15]) and B (69% [24/35]) than in group C (36% [10/28]) (A + B vs C, P =.009; chi(2) test; age adjusted). Conclusion The prevalence of HPV in the skin (hair follicles) is increased in patients with psoriasis who have a history of PUVA exposure.

The rash of measles is caused by a viral infection in the cells of the skin: a case report.

Measles skin rash was immunohistochemically examined in an effort to detect virus antigen in skin samples taken from a 15-year-old girl with measles. A sectioned specimen obtained by punch biopsy from a 2nd-day skin lesion showed localized parakeratosis and acanthosis with multinucleated giant cells in the epidermis, thickening and cellular edema of epithelia in the hair follicles, and vascular dilation in the papillary plexus. Measles virus antigen was detected by ABC immunoperoxidase in the epidermis, follicular epithelia, and lympho-histiocytic cell infiltrates in the upper of the dermis. This rash deemed to be caused in part by direct viral infection of the epidermal cells.

Sample type is vital for diagnosing infection with peste des petits ruminants virus by reverse transcription PCR.

Peste des petits ruminants (PPR) diagnosis from suspected samples from sheep and goats was carried out. Buffy coat, tissues, and oculo-nasal swabs were analyzed using nucleoprotein (NP3/NP4) and fusion protein (F1/F2) gene primers, respectively. Analysis of the sample types and primer set revealed that buffy coat are the best type of samples for PPR diagnosis and the use of two set of primers will increase the number of positives.

Development of a novel diagnostic test for detection of bovine viral diarrhea persistently infected animals using hair.

The purpose of this study was to determine whether manually plucked hairs might serve as an alternative sample for a quantitative real time polymerase chain reaction (qRT-PCR) testing. Twenty three, 1~3 week old, non-bovine viral diarrhea virus (BVDV) vaccinated calves, found to be positive for BVDV by immunohistochemical staining, were selected and hairs were manually plucked from the ear. qRT-PCR was performed on samples consisting of more than 30 hairs (30~100) and whole blood. All 23 animals were positive for the virus by qRT-PCR performed on the whole blood and when samples of more than 30 hairs were assayed. Additionally, qRT-PCR was performed on groups of 10 and 20 hairs harvested from 7 out of 23 immunohistochemical staining-positive calves. When groups of 20 and 10 hairs were tested, 6 and 4 animals, respectively, were positive for the virus.

Anogenital hairs are an important reservoir of alpha-papillomaviruses in patients with genital warts.

Human papillomaviruses (HPVs) were detected in 69 (43.7%) of 158 and in 7 (4.5%) of 155 anogenital hairs obtained from 53 patients with genital warts (GWs) and from 53 age-matched healthy control subjects, respectively. At least 1 hair sample was positive for 69.8% of patients and for 13.2% of control subjects. For patients, HPV was detected in 64.2%, 39.6%, and 26.9% of hairs plucked from the pubic, scrotal, and perianal regions, respectively. For 91.9% of patients, the same HPV genotype was identified in GWs and hairs from at least 1 sampling site. Having GWs was found to be strongly associated with the presence in anogenital hairs of the HPV genotype causing the GWs (range of odds ratios, 13.0-20.0).

Betapapillomaviruses frequently persist in the skin of healthy individuals.

Infections with human papillomaviruses (HPVs) belonging to the genus Betapapillomavirus have been linked to the development of non-melanoma skin cancer. Although persistence is expected, systematic investigation of this aspect of betapapillomavirus (beta-PV) infection has not been conducted. This study investigated the prevalence and persistence of 25 known beta-PV types in the skin of immunocompetent individuals. Over a 2 year period, eight consecutive plucked eyebrow hair samples taken from 23 healthy individuals were analysed for the presence of beta-PV DNA. Using a recently published general beta-PV PCR and genotyping method, 61% of the individuals were beta-PV DNA positive for one or more types at intake, whereas during follow-up this percentage rose to 96%. HPV23 was the most frequently detected beta-PV type. Type-specific beta-PV DNA was detected over 6 months or longer in 74% of the individuals. In 57% of the individuals, DNA from multiple beta-PV types was detected simultaneously for 6 months or longer. When the detection intervals of all beta-PV type-specific infections in the study population were considered, a substantial proportion, 48%, lasted at least half a year. The consistent beta-PV patterns found over time in most individuals strongly suggested that beta-PV DNA detection in plucked eyebrow hairs reveals true beta-PV infection. If the minimum interval of detection was set at 6 months, persistent beta-PV infections were found in the majority of the study population (74%).