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Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in‐house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV‐A71, echovirus 30, coxsackie A virus 21, and EV‐D68), HPeV3, and specificity controls. Reported results from 48 in‐house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 µL) transcripts. In‐house assays showed significantly greater detection frequencies of the low copy (10 copies/5 µL) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 × 10−5). EV‐specific PCRs showed low cross‐reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in‐house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point‐of‐care tests. © 2019 The Authors. Journal of Medical Virology published by Wiley Periodicals, Inc. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Palatine tonsils have been observed to harbor several distinct respiratory and herpesviruses in separate studies. In this study, the presence of these viruses in palatine tonsils was comprehensively studied in both children and adults. A cross‐sectional analysis of 181 patients (median age 22 years; range, 2.6‐66) operated for a benign tonsillar disease was conducted. Real‐time polymerase chain reaction was performed to detect 27 distinct viruses in all: eight human herpesviruses, 16 respiratory viruses, parvo B19, and polyoma BK/JC viruses. Clinical characteristics of the patients and underlying conditions were evaluated. In total, 92% of patients had virus detected in tonsils (Epstein‐Barr virus 72%, human herpesvirus 7, and 6B 54% and 16%, respectively, enterovirus 18%, parvovirus B19 7% and the rest, Highlights This study comprehensively reports a cross‐sectional view of intratonsillar virus infections in 181 elective tonsillectomy patients (median age 22 years, range 2.6–66). Enterovirus was more common in children and was frequently observed in the presence of HHV6B. Tonsils are a major virus reservoir for distinct herpes and respiratory viruses without a positive association with tonsillar disease or respiratory symptoms.

This study reports a previously healthy, immunocompetent adult male in whom human herpesvirus 7 (HHV-7) DNA was detected continuously from the cerebrospinal fluid (CSF). This patient developed definite sarcoidosis with primary symptomatic manifestations in the central nervous system (CNS). The initial presentation was with loss of visual acuity and papilledema. Brain MR imaging at presentation confirmed papilledema, but otherwise there were no focal abnormalities or signs of hydrocephalus. CSF investigation revealed pleocytosis and elevated protein levels. HHV-7 DNA was detected repeatedly from CSF but not from blood over 1 year follow-up. High resolution computed tomography of lungs was normal. Positron emission tomography showed several metabolically active lymph nodes in the mediastinum, and the histopathological investigation revealed granulomatous inflammation consistent with sarcoidosis. The finding of HHV-7 DNA in the CSF in the context of neurosarcoidosis has not been reported previously. The detection of HHV-7 DNA may result from the selective activation of CD4+ T-lymphocytes in the CSF caused by neurosarcoidosis. Further studies are needed to establish whether the detection of HHV-7 DNA in the CSF in association with neurosarcoidosis represents a clinically significant HHV-7 CNS infection.

The clinical data on the first wheezing episodes induced by different rhinovirus (RV) species are still limited. We aimed to investigate the prevalence of RV genotypes, sensitization status, and clinical characteristics of patients having a respiratory infection caused by either different RV species or other respiratory viruses. The study enrolled 111 patients (aged 3-23 months, 79% hospitalized, 76% with RV infection) with the first wheezing episode. RV-specific sequences were identified by partial sequencing of VP4/VP2 and 5' non-coding regions with 80% success rate. The investigated clinical and laboratory variables included atopic characteristics and illness severity, parental atopic illnesses, and parental smoking. Of the study children, 56% percent had >1 atopic characteristic (atopy, eczema and/or blood eosinophil count >0.4 × 109 /L) and 23% were sensitised to allergens. RV-C was detected in 58% of RV positive samples, followed by RV-A (20%) and RV-B (1.2%). Children with RV-A and RV-C induced wheezing were older (P = 0.014) and had more atopic characteristics (P = 0.001) than those with non-RV. RV-A and RV-C illnesses had shorter duration of preadmission symptoms and required more bronchodilator use at the ward than non-RV illnesses (both P

This study reports a previously healthy, immunocompetent adult male in whom human herpesvirus 7 (HHV-7) DNA was detected continuously from the cerebrospinal fluid (CSF). This patient developed definite sarcoidosis with primary symptomatic manifestations in the central nervous system (CNS). The initial presentation was with loss of visual acuity and papilledema. Brain MR imaging at presentation confirmed papilledema, but otherwise there were no focal abnormalities or signs of hydrocephalus. CSF investigation revealed pleocytosis and elevated protein levels. HHV-7 DNA was detected repeatedly from CSF but not from blood over 1 year follow-up. High resolution computed tomography of lungs was normal. Positron emission tomography showed several metabolically active lymph nodes in the mediastinum, and the histopathological investigation revealed granulomatous inflammation consistent with sarcoidosis. The finding of HHV-7 DNA in the CSF in the context of neurosarcoidosis has not been reported previously. The detection of HHV-7 DNA may result from the selective activation of CD4+ T-lymphocytes in the CSF caused by neurosarcoidosis. Further studies are needed to establish whether the detection of HHV-7 DNA in the CSF in association with neurosarcoidosis represents a clinically significant HHV-7 CNS infection.

The persistence of rhinovirus and enterovirus RNAs was studied in the nasal secretions of children with acute expiratory wheezing (median age: 1.7 years). On admission, 84 samples from 161 (52%) children admitted to hospital were positive by reverse transcriptase-polymerase chain reaction (RT-PCR), which detects rhino- and enteroviruses simultaneously. Of the samples, 26 (16%) were positive for rhinovirus, 29 (18%) enterovirus and 29 (18%) nontypable rhino-enterovirus. After 2 weeks, 16 of these 84 (19%) samples were still positive. Rhinovirus RNA remained positive in 13 of 26 (50%) cases, whereas enterovirus RNA remained positive only in 1 of 29 (3%) cases (P=0.0001). Respiratory symptoms at 2 weeks or systemic glucocorticoid treatment during hospital stay were not related to the persistence of viral RNA. After 5 weeks, only one sample remained PCR-positive. Thirteen of the 79 (16%) asymptomatic control children were PCR-positive for respiratory picornavirus. Five of the 13 (38%) PCR-positive children developed respiratory symptoms in the following week. The study shows that after the onset of symptomatic respiratory infection enterovirus RNA may take 2-3 weeks and rhinovirus RNA 5-6 weeks to disappear from nasal mucus.