Rhinoviruses and Respiratory Enteroviruses: Not as Simple as ABC

Abstract

Rhinoviruses (RVs) and respiratory enteroviruses (EVs) are leading causes of upper respiratory tract infections and among the most frequent infectious agents in humans worldwide. Both are classified in the Enterovirus genus within the Picornaviridae family and they have been assigned to seven distinct species, RV-A, B, C and EV-A, B, C, D. As viral infections of public health significance, they represent an important financial burden on health systems worldwide. However, the lack of efficient antiviral treatment or vaccines against these highly prevalent pathogens prevents an effective management of RV-related diseases. Current advances in molecular diagnostic techniques have revealed the presence of RV in the lower respiratory tract and its role in lower airway diseases is increasingly reported. In addition to an established etiological role in the common cold, these viruses demonstrate an unexpected capacity to spread to other body sites under certain conditions. Some of these viruses have received particular attention recently, such as EV-D68 that caused a large outbreak of respiratory illness in 2014, respiratory EVs from species C, or viruses within the newly-discovered RV-C species. This review provides an update of the latest findings on clinical and fundamental aspects of RV and respiratory EV, including a summary of basic knowledge of their biology.

A molecular epidemiological perspective of rhinovirus types circulating in Amsterdam from 2007 to 2012

“…Our study monitored circulation of RVs over a relatively long time period, which allowed us to examine the circulation of RV species and types over 6 years, thereby limiting the influence of single outbreaks. Our observation that RVs circulate during the whole year has been found repeatedly [1,8]. Interestingly, Linder et al also reported a dominance of RV-C in the winter months [30].…”

“…The same holds true for EV-C104, which was detected in five samples (from four infections). The other EVs detected are found only occasionally in respiratory samples [8,29].…”

“…Studies suggested that RV-C infections may elicit more severe disease compared with infections with RV-A or RV-B types [8]. However, this has been refuted by several studies that did not observe a difference in outcome between RV-C and RV-A infections [8]. Due to the large number of RV types, the severity of infections caused by individual RV types is even more elusive.…”

Adenovirus type 4 respiratory infections with a concurrent outbreak of coxsackievirus A21 among United States Army Basic Trainees, a retrospective viral etiology study using next‐generation sequencing

“…Human enteroviruses are the most prevalent viral pathogens which produce diseases ranging from asymptomatic infections to deadly syndromes . Using current clinical diagnostics and respiratory surveillance methodologies, rhinoviruses, and enteroviruses are not often identified to the species level.…”

Enterovirus D-68 Infection, Prophylaxis, and Vaccination in a Novel Permissive Animal Model, the Cotton Rat (Sigmodon hispidus)

“…Picornaviruses of the genus Enterovirus (EV) comprise many human pathogens that cause most common infections in humans, such as EV A-D and rhinovirus (RV) A-C [1]. The EVs are small, single-stranded, positive-sense RNA viruses with a genome of ~7.5 kb, encapsidated into an icosahedral capsid, forming a non-enveloped virion of around 30 nm diameter.…”