Poliovirus Excretion in Children with Primary Immunodeficiency Disorders, India

Prolonged excretion of poliovirus can occur in immunodeficient patients who receive oral polio vaccine, which may lead to propagation of highly divergent vaccine-derived polioviruses (VDPVs), posing a concern for global polio eradication. This study aimed to estimate the proportion of primary immunodeficient children with enterovirus infection and to identify the long-term polio/nonpolio enterovirus excreters in a tertiary care unit in Mumbai, India. During September 2014–April 2017, 151 patients received diagnoses of primary immunodeficiency (PID). We isolated 8 enteroviruses (3 polioviruses and 5 nonpolio enteroviruses) in cell culture of 105 fecal samples collected from 42 patients. Only 1 patient with severe combined immunodeficiency was identified as a long-term VDPV3 excreter (for 2 years after identification of infection). Our results show that the risk of enterovirus excretion among children in India with PID is low; however, systematic screening is necessary to identify long-term poliovirus excreters until the use of oral polio vaccine is stopped.

An outbreak of acute haemorrhagic conjunctivitis associated with coxsackievirus A24 variant in The Gambia, West Africa

OBJECTIVE

An outbreak of acute haemorrhagic conjunctivitis occurred in The Gambia, West Africa in 2011. Affected individuals presented with conjunctival haemorrhages, swelling and ocular discharge. In an effort to identify a causative agent of the disease, ocular swabs were taken from patients during the acute and convalescent phases. Total RNA was extracted from all samples and reverse-transcriptase PCR performed using primers specific for all enteroviruses. Resulting amplicons were sequenced and data compared to known sequences using the BLAST algorithm.

RESULTS

Forty-eight swabs were included in the analysis. Of these, 21 acute and 9 convalescent swabs (65% of the total) gave positive PCR results. Sequence analysis of the resulting amplicons indicated 99% sequence identity with coxsackievirus A24 variant identified during independent outbreaks of acute haemorrhagic conjunctivitis around the world and suggest the Gambian outbreak was due to this virus.

Acute Flaccid Paralysis Associated with Novel Enterovirus C105

An outbreak of acute flaccid paralysis among children in the United States during summer 2014 was tentatively associated with enterovirus D68 infection. This syndrome in a child in fall 2014 was associated with enterovirus C105 infection. The presence of this virus strain in North America may pose a diagnostic challenge.

Isolation of Coxsackievirus A24 variant from patients with hemorrhagic conjunctivitis in Cuba, 2008-2009

BACKGROUND

An outbreak of acute hemorrhagic conjunctivitis occurred in Cuba in 2008 and 2009.

OBJECTIVE

To determinate the etiological agent associated with the Cuban outbreaks of acute hemorrhagic conjunctivitis during 2008 and 2009.

STUDY DESIGN

Conjunctival swabs and/or faecal samples from 382 patients with clinical diagnosis suggestive of acute hemorrhagic conjunctivitis were subject to viral culture in HEp-2 human laryngeal epidermoid carcinoma cells. Positive samples were identified by a specific Coxsackievirus A24 variant PCR and the 3C protease region of 16 isolates was sequenced for phylogenetic analysis.

RESULTS

Enterovirus cytopathic effect was observed in 138 cases (36%). A higher percent of CA24v was recovered from faecal samples, 19 out of 45 cases (42.2%), than from conjunctival swabs, 127 out of 355 samples (35.8%). All isolates were identified as Coxsackievirus A24 variant. Phylogenetic analysis revealed that 2008 and 2009 Cuban outbreaks were caused by the same virus strains and that isolates were closely related to those from Taiwan (2006-2007), China (2007-2008) and Singapore (2005) with a bootstrap value of 71%.

CONCLUSIONS

Outbreaks of acute hemorrhagic conjunctivitis occurred in Cuba in 2008 and 2009 were caused by Coxsackievirus A24 variant. The faecal-oral route is another mode of transmission of CA24v in the acute hemorrhagic conjunctivitis outbreaks. Phylogenetic analysis of Cuban CA24v strains involved in an acute hemorrhagic conjunctivitis outbreak in 2008 and 2009 confirms a new introduction of the CA24 variant into the Americas from South-east Asia.

[Identification of infection agent in diagnostic material from patients with suspicion of enteroviral meningitis]

Clinical diagnosis of enteroviral infections of the central nervous system are performed by virus isolation in sensitive cell lines and RT-PCR assay. The aim of the study was evaluation these techniques for fast diagnosis meningitis caused by enteroviruses. 69 samples (cerebrospinal fluid, CSF) were collected and analised by RT-PCR reaction. 39 samples were positive (56.5%). 20 positive sample were selected and simultaneously 20 stool samples from the same patients were collected for virus isolation in sensitive cell line. Positive isolation was observed only in one CSF (5.3%) and in 9 stool samples (45%).

[Enteroviruses serotypes isolated in years 2008-2009 in NIPH-NIH]

Enteroviruses are important etiologic agents of many human diseases such as diarrhea, self-limiting gastroenteritis, respiratory infections, conjunctivitis, hepatitis, aseptic meningitis, encephalitis, and paralysis. The aim of this study was the evaluation of the frequency of enteroviral infections in Poland in 2008-2009. Out of 178 clinical materials tested for the presence of enteroviruses, 24 samples (13,5%) were positive. In the case of 153 samples from patients suffering from acute flaccid paralysis (AFP), positive results were obtained for 6 samples (4%). Moreover, 25 samples coming from patients with clinical symptoms caused by nonpoliomyelitic enteroviruses were analyzed, giving 18 positive results (72%). The most frequently isolated enterovirus serotypes were Coxsackie B (25%), ECHO30 (25%) i ECHO6 (21%).

Outbreak of acute hemorrhagic conjunctivitis in Maharashtra and Gujarat states of India, caused by Coxsackie virus A-24 variant

Acute hemorrhagic conjunctivitis is associated with enteroviruses. Among these, Coxsackie A-24 variant (CA-24) and Enterovirus-70 (EV-70) are known to cause epidemics and pandemics. An outbreak of acute hemorrhagic conjunctivitis occurred in August-September 2003 in Maharashtra and Gujarat states of India. The present investigation was carried out to determine the viral etiological agent associated with the epidemic. Virus isolates were obtained from 11 eye swabs of conjunctivitis patients using HeLa/ Hep-2 cell lines. The isolates were characterized by serological and mouse pathogenecity tests, RT-PCR using enterovirus common primers (VP4-VP2), CA-24 specific primers (3C-proteinase region), EV-70 primers (VP-3) followed by sequencing, and phylogenetic analysis. The virus was characterized as a Coxsackie A-24 variant (CA-24v) and none of the isolates were found to be positive for EV-70. Sequencing of the PCR products derived from all the 11 isolates revealed 98.4% (SE 0.20) nucleotide identity within the Indian strains and 98.6% (0.50) and 94.4% (0.30) nucleotide identity respectively with the West Indies and Asian strains reported worldwide. The findings suggest that the outbreak of acute hemorrhagic conjunctivitis that occurred in Maharashtra and Gujarat states of India during August-September 2003 was caused by the Coxsackie A-24 variant (CA-24v).

Functional impairment and killing of human beta cells by enteroviruses: the capacity is shared by a wide range of serotypes, but the extent is a characteristic of individual virus strains

AIMS/HYPOTHESIS

Direct infection of beta cells could explain the diabetogenic effect of enteroviruses. Primary adult human beta cells are susceptible to coxsackievirus infections, which could result in impaired beta-cell function or cell death (coxsackieviruses B3, B4, B5) or both, or no apparent immediate adverse effects (coxsackievirus A9). We extended these studies to additional enterovirus serotypes including several echoviruses, some of which have been associated clinically with the development of Type I (insulin-dependent) diabetes mellitus.

METHODS

The patterns and consequences of enterovirus infections were investigated in cultured adult human isolated islets. Cell type-specific infection and viability were assessed by immunocytochemical methods. Beta-cell function was studied by perifusion.

RESULTS

Poliovirus type 1/Mahoney, coxsackievirus A13, human parechovirus 1 and several echoviruses (serotypes 6, 7, 11) were capable of causing significant functional impairment ( p<0.05) and beta-cell death. In contrast, echovirus serotypes 9 and 30 were not destructive. However, when several different field isolates of echovirus 30 were investigated, some of them were found to be clearly more destructive than the corresponding prototype strain. This was also true for echovirus 9. A strain isolated from a 6-week-old baby suffering from acute Type I diabetes was functionally more destructive than either of the echovirus 9 prototype strains.

CONCLUSION/INTERPRETATION

These observations indicate that the capacity of an enterovirus to kill human beta cells or impair their function is not entirely defined by the serotype, but in addition by as yet unidentified characteristics of the virus strain involved. Moreover, any serotype could potentially be diabetogenic.