Hand, Foot, and Mouth Disease Caused by Coxsackievirus A6: A Preliminary Report from Istanbul

[Efficiency of benzydamine use in treatment of URTI (including COVID-19) in child patients]

Share with healthcare practitioners personal experience of using benzydamine spray (Oralsept) in pediatric practice; present a clinical case, which, according to the author, can help doctors optimize approaches to the treatment of patients with acute respiratory viral infections (including COVID-19), thereby improving the quality of life of pediatric patients.

[Herpangina. Clinical case]

Enterovirus infections are a group of acute infectious diseases caused by enteroviruses (including Coxsackie A and B viruses, ECHO viruses), which clinically present symptoms of damage to the central nervous system, cardiovascular system, gastrointestinal tract, muscular system, mucous membranes and skin, fever. This article presents a clinical case of patient L., 12 years old, who admitted to an otorhinolaryngologist with clinical manifestations of herpangina. The diagnosis was confirmed by PCR. The patient was prescribed, adequate rehydration, diet with the exclusion of salty, spicy and fried foods, restriction of physical activity, exclusion of thermal procedures, Benzydamine Spray (Oralsept) 0.255 mg/dose, 6 doses 3 times/day, topically, on demand and inosine pranobex (Groprinosin) in a daily dose of 50 mg/kg of body weight: 1 tablet 500 mg 4 times a day for 7 days (at the rate of 1 tablet of 500 mg per 10 kg of body weight; for a patient weighing 41 kg - 4 tablets per day). On the 10th day from the onset of the disease, the docter noted a complete regression of clinical symptoms and the patient was discharged with recovery.

Genetic recombination in fast-spreading coxsackievirus A6 variants: a potential role in evolution and pathogenicity

Hand, foot, and mouth disease (HFMD) is a common global epidemic. From 2008 onwards, many HFMD outbreaks caused by coxsackievirus A6 (CV-A6) have been reported worldwide. Since 2013, with a dramatically increasing number of CV-A6-related HFMD cases, CV-A6 has become the predominant HFMD pathogen in mainland China. Phylogenetic analysis based on the VP1 capsid gene revealed that subtype D3 dominated the CV-A6 outbreaks. Here, we performed a large-scale (near) full-length genetic analysis of global and Chinese CV-A6 variants, including 158 newly sequenced samples collected extensively in mainland China between 2010 and 2018. During the global transmission of subtype D3 of CV-A6, the noncapsid gene continued recombining, giving rise to a series of viable recombinant hybrids designated evolutionary lineages, and each lineage displayed internal consistency in both genetic and epidemiological features. The emergence of lineage –A since 2005 has triggered CV-A6 outbreaks worldwide, with a rate of evolution estimated at 4.17 × 10⁻³ substitutions site^-1 year⁻¹ based on a large number of monophyletic open reading frame sequences, and created a series of lineages chronologically through varied noncapsid recombination events. In mainland China, lineage –A has generated another two novel widespread lineages (–J and –L) through recombination within the enterovirus A gene pool, with robust estimates of occurrence time. Lineage –A, –J, and –L infections presented dissimilar clinical manifestations, indicating that the conservation of the CV-A6 capsid gene resulted in high transmissibility, but the lineage-specific noncapsid gene might influence pathogenicity. Potentially important amino acid substitutions were further predicted among CV-A6 variants. The evolutionary phenomenon of noncapsid polymorphism within the same subtype observed in CV-A6 was uncommon in other leading HFMD pathogens; such frequent recombination happened in fast-spreading CV-A6, indicating that the recovery of deleterious genomes may still be ongoing within CV-A6 quasispecies. CV-A6-related HFMD outbreaks have caused a significant public health burden and pose a great threat to children’s health; therefore, further surveillance is greatly needed to understand the full genetic diversity of CV-A6 in mainland China.