Should Enteroviruses Be Monitored in Natural Recreational Waters?

Enteroviruses (EVs) infections occur worldwide. Although, infections by these viruses are often asymptomatic and go unnoticed, they can be shed in stool for several weeks. The EVs are associated with sporadic outbreaks and a wide range of clinical symptoms, occasionally accompanied with fatal consequences. Presently in the Slovak Republic (SR) recreational waters are tested only for bacterial indicators. Our aim was to monitor EVs in recreational waters. Water samples were collected during the years 2012-2014 from different recreational natural lakes in Central and West regions of SR. The samples were concentrated by centrifugation using the two-phase separation method recommended by the World Health Organization (WHO) used for EVs surveillance in the treated sewage waste water. Each of the two phases collected from the samples was analysed by polymerase chain reaction for detection of EVs and primary sequencing was done. Our study demonstrated presence of EVs in three localities consecutively for three years, indicating a probability of constant local source of faecal contamination. This is the first monitoring report on the occurrence of EVs in the natural recreational waters in SR.

Pathophysiology of the pancreas after oral infection of genetically diverse mice with coxsackievirus B4-E2.

Coxsackievirus B4 strain E2 (CVB4-E2) and its association with type 1 diabetes (T1D) have been studied in experimental in vitro and in vivo murine models. CVB4-E2, known to be pancreotropic and diabetogenic in nature, is associated with acute pancreatitis in mice but shows differences in the induction of glycemia after intraperitoneal (i.p.) infection. Therefore, the aim of this work was to study the outcome of oral infection with CVB4-E2 in five mouse strains with different genetic backgrounds: two outbred (Swiss albino, CD1), two inbred (SJL, NOD) and one transgenic (NOD.SCID). Survival rates, fasting blood glucose, histopathology, viral titres and persistence were studied in selected organs and stool samples. Viral protein (VP1), proinflammatory cytokines, and interferon alpha (IFN-α) were analyzed by immunohistochemistry. We observed mortality only in infected NOD and NOD.SCID mice, with differing survival rates implying initial innate protection in the NOD.SCID mice and low virus clearance with replicating virus titres in the studied organs and stool up to day 40 post infection (p.i.). Independent of the mouse strain hyperglycemia, proinflammatory cytokines and histopathological changes were absent in the endocrine pancreas of infected mice. Only the pancreata of the dead NOD.SCID mice showed inflammation even in presence of IFN-α. Host-dependent viral RNA persistence was observed in all outbred mice. In conclusion, oral infection with CVB4-E2, despite the known affinity of this strain towards the pancreatic tissue and the presence of replicating virus, conferred total protection to the endocrine pancreas in all mice and failed to induce the proinflammatory cytokines studied by us.

Pancreas of coxsackievirus-infected dams and their challenged pups: A complex issue.

Enteroviral infections are frequent, often asymptomatic in humans and during gravidity. The present study is an extension of our previous investigations where we had shown pancreatitis in challenged pups of CVB4-E2-infected dams. Present investigation describes the effect of gestational infection with this virus on the pancreas of both dams and their challenged pups. Gravid CD1 outbred mice were orally infected with CVB4-E2 virus at different gestation times. Pups were challenged orally with the same virus after 25 days of birth. Organs were collected at selected intervals postinfection (p.i.), and replicating virus and viral-RNA copies were analyzed. Additional readouts included histopathology and immunohistochemical (IHC) analysis for localization and identification of Ly6G+ cells (neutrophils), CD11b+ cells (macrophages), and viral protein in pancreatic tissue sections of the infected dams and their challenged pups. Our results show the presence of replicating virus in the pancreas of infected dams and their challenged pups, with inflammation leading to chronic necrotizing pancreatitis and atrophy of pancreatic acini of the dams and their offspring. IHC analysis of the infiltrating cells showed pronounced Ly6G+ neutrophils in dams only, whereas CD11b+ macrophages were present in tissues of both, the pups and the dams. Time of infection during gravidity as well as the p.i. intervals when mice were sacrificed influenced the pancreatic pathophysiology in both groups. We conclude that coxsackievirus infection during pregnancy is a risk factor for chronic affliction of the exocrine tissue and could affect endocrine pancreas in the mother and child.

Assessment of a swab collection method without virus transport medium for PCR diagnosis of coxsackievirus infections.

Classically, detection of human enterovirus (EV) infections is based on virus isolation in tissue culture, proper sample collection and handling that optimizes virus viability. Samples are collected in virus transport medium (VTM) to ensure virus stability. High sensitivity and rapid results have made polymerase chain reaction (PCR) analysis increasingly popular for routine diagnosis. The PCR method enables simple sample collection and storage for EV diagnostics, which may eventually allow self-sampling at home. Our aim was to test a modification of the conventional clinical swab sample collection method for molecular diagnosis of EV infection. We compared swabs (cotton or synthetic) without VTM and the classical standard synthetic swabs with VTM. Effects of storage temperature (+4 °C or -80 °C) and duration were studied. EV-RNA could be detected by reverse transcriptase and nested PCR in both swab types without VTM. Differences depended on the storage duration and temperature. Optimum conditions were immediate processing or storage at -80 °C. Storage without VTM at +4 °C for longer periods is not advisable. We conclude that swabs without VTM can be considered for clinical EV-diagnostics based on PCR, and ultimately for epidemiological sample collection.

Type I diabetes mellitus: genetic factors and presumptive enteroviral etiology or protection.

We review type 1 diabetes and host genetic components, as well as epigenetics and viruses associated with type 1 diabetes, with added emphasis on the enteroviruses, which are often associated with triggering the disease. Genus Enterovirus is classified into twelve species of which seven (Enterovirus A, Enterovirus B, Enterovirus C, and Enterovirus D and Rhinovirus A, Rhinovirus B, and Rhinovirus C) are human pathogens. These viruses are transmitted mainly by the fecal-oral route; they may also spread via the nasopharyngeal route. Enterovirus infections are highly prevalent, but these infections are usually subclinical or cause a mild flu-like illness. However, infections caused by enteroviruses can sometimes be serious, with manifestations of meningoencephalitis, paralysis, myocarditis, and in neonates a fulminant sepsis-like syndrome. These viruses are often implicated in chronic (inflammatory) diseases as chronic myocarditis, chronic pancreatitis, and type 1 diabetes. In this review we discuss the currently suggested mechanisms involved in the viral induction of type 1 diabetes. We recapitulate current basic knowledge and definitions.

Preterm prelabor rupture of membranes (PPROM) is not associated with presence of viral genomes in the amniotic fluid.

BACKGROUND: The role of viral infections in preterm prelabor rupture of the membranes (PPROM) is not established. Studies on the presence of viral genomes in the amniotic fluid (AF) collected in pregnancies complicated by PPROM show contradictory outcomes. OBJECTIVES: To investigate AF samples of PPROM pregnancies for the presence of viral genomes. STUDY DESIGN: AF samples from patients with PPROM were collected during a 4-year (2008-2012) observational study. 174 women were included with selection criteria of singleton pregnancy, PPROM, and maternal age of 18 years and above. PCR was used for detection of human cytomegalovirus (HCMV), herpes simplex virus (HSV), parvovirus B19, human adenoviruses (HAdV), enteroviruses (EV) and human parechovirus (HPeV). The selection of these viral targets was based on literature regarding screening of AF for presence of viral genomes. RESULTS: Only a single sample was positive out of the 174 tested AFs, HCMV DNA was detected. CONCLUSIONS: PPROM is not associated with active viral infections.