Enteroviruses and Rhinoviruses: Molecular Epidemiology of the Most Influenza-Like Illness Associated Viruses in Senegal

Abstract

Abstract. Different viruses have been identified as etiologic agents of respiratory tract infections, including severe cases. Among these, human rhinoviruses (HRVs) and human enteroviruses (HEVs) are recognized as leading causes. The present study describes the molecular epidemiology of HRVs and HEVs in Senegal over a 3-year surveillance period. From January 2012 to December 2014, nasopharyngeal and oropharyngeal swabs specimen were collected from patients with influenza-like illness (ILI). A real-time reverse transcription polymerase chain reaction was performed for HRV and HEV detection using the RV16 kit. Two regions were targeted for the molecular characterization of RVs: 5′ untranslated region (5′UTR) and viral protein 4/viral protein 2 (VP4/VP2) transition region. For enteroviruses (EVs) phylogeny, VP1 gene was targeted. A total of 4,194 samples were collected. Children up to 5 years accounted for 52.9%. Among them, 1,415 (33.7%) were positive for HRV, 857 (20.4%) for HEV, and 437 cases of dual infections HRV/HEV. HRVs and HEVs were identified significantly in children aged 5 years or less. Only cough and vomiting signs were observed with significant association with viral infection. Both viruses co-circulated all year long with a marked increase of activity during rainy and cold period. All HRV types circulate in Senegal. HRV-A and C groups were the most common. HEV serotyping identified coxsackie B viruses (CBV) only. VP1 region revealed different CBV (CBV1, CBV2, CBV3, CBV4, and CBV5), echoviruses, coxsackieviruses A4-like strains and a poliovirus 2. The results suggest strong year-round respiratory picornavirus activity in children up to 5 years of age. Molecular studies identified a wide variety of RVs along with diverse EVs in samples from patients with ILI.

Children under five years of age in senegal: A group highly exposed to respiratory viruses infections

“…This high circulation of picornaviruses in children was clearly reflected in the data collected after many years of surveillance of these viruses in people in Senegal [9]. Interestingly, in the present pediatric study about 59.7% of picornaviruses infection cases are related to low respiratory tract infections (LRTIs) although these viruses are usually related to mild URTI.…”

“…The most common viruses associated with influenza-like illness (ILI) in patients were influenza viruses, adenoviruses (ADVs), human rhinoviruses (HRVs), respiratory syncytial virus (RSV), enteroviruses (EVs), parainfluenza viruses (PIVs), human metapneumovirus (hMPV), and human coronaviruses (HCoVs) 229E, OC43, NL63, and HKU1. Studies focused on HRV and RSV, have revealed a high activity of both viruses in children under 5 in Senegal, especially during the rainy season [9,10]. Indeed, previous studies have well established that RSV is the leading cause of lower respiratory tract infections (LRTIs) in young children with 50% of children infected during their first year of life, and 100% having experienced at least one infection by 3 years of age [11].…”

High frequency of Polio-like Enterovirus C strains with differential clustering of CVA-13 and EV-C99 subgenotypes in a cohort of Malawian children

“…Secondly, we hypothesize that our high EV prevalence is further explained by our relatively young population. While other studies often focus on a broader age group, EV’s are more prevalent in young age groups, when compared to older children and adults [ 15 , 19 ]. Thirdly, the inclusion criteria of the SevAna study led to a higher number of participants included during the rainy season, in which malaria, a well-known cause of anemia, is highly prevalent.…”

Pathogens Causing Respiratory Tract Infections in Children Less Than 5 Years of Age in Senegal

“…14,15 Viruses most commonly found in Senegal were respiratory syncytial virus (RSV ), adenovirus, rhinovirus, influenza virus A, enterovirus, human bocavirus, and parainfluenza viruses. 16 Furthermore, there are indications that nowadays ARTIs are more often caused by the sequential or concurrent interaction of different pathogens and that the presence of multiple organisms is linked with the existence of a LRTI and with severity of disease. 17,18 To reduce paediatric mortality caused by LRTI, while fighting antibiotic resistance, more knowledge about the cause of respiratory infections, especially in low-and middle-income countries, is essential.…”