Fonseca Magilé C, Pupo-Meriño Mario, García-González Luis A, Muné Mayra, Resik Sonia, Norder Heléne, Sarmiento Luis
Virology Department, Center for Research Diagnosis, and Reference, Institute of Tropical Medicine "Pedro Kourí", Havana 11400, Cuba.
Departamento de Bioinformática, Universidad de las Ciencias Informáticas (UCI), Habana 19370, Cuba.
Microorganisms. 2021 Mar 5;9(3):531. doi: 10.3390/microorganisms9030531.
Coxsackievirus A24 variant (CVA24v), the main causative agent of acute hemorrhagic conjunctivitis (AHC), can be isolated from both the eyes and lower alimentary tract. However, the molecular features of CVA24v in feces is not well-documented. In this study, we compared the VP1 and 3C sequences of CVA24v strains isolated from feces during AHC epidemics in Cuba in 1997, 2003, and 2008-2009 with those obtained from conjunctival swabs during the same epidemic period. The sequence analyses of the 3C and VP1 region of stool isolates from the three epidemics showed a high degree of nucleotide identity (ranging from 97.3-100%) to the corresponding conjunctival isolates. The phylogenetic analysis showed that fecal CVA24v isolates from the 1997 and 2003 Cuban outbreaks formed a clade with CVA24v strains isolated from conjunctival swabs in Cuba and other countries during the same period. There were three amino acid changes (3C region) and one amino acid change (VP1 region) in seven CVA24v strains isolated sequentially over 20 days from fecal samples of one patient, suggesting viral replication in the intestine. Despite these substitutions, the virus from the conjunctival swab and fecal samples were genetically very similar. Therefore, fecal samples should be considered as a reliable alternative sample type for the routine molecular diagnosis and molecular epidemiology of CVA24v, also during outbreaks of AHC.
柯萨奇病毒A24变异株（CVA24v）是急性出血性结膜炎（AHC）的主要病原体，可从眼部和下消化道分离得到。然而，粪便中CVA24v的分子特征尚无充分记录。在本研究中，我们将1997年、2003年以及2008 - 2009年古巴AHC流行期间从粪便中分离出的CVA24v毒株的VP1和3C序列，与同一流行期间从结膜拭子中获得的序列进行了比较。对三次流行中粪便分离株的3C和VP1区域进行的序列分析表明，其与相应的结膜分离株具有高度的核苷酸同一性（范围为97.3 - 100%）。系统发育分析显示，1997年和2003年古巴疫情中粪便来源的CVA24v分离株与同期古巴及其他国家从结膜拭子中分离出的CVA24v毒株形成一个进化枝。在从一名患者粪便样本中连续20天分离出的7株CVA24v毒株中，有3个氨基酸变化（3C区域）和1个氨基酸变化（VP1区域），提示病毒在肠道中复制。尽管有这些替换，结膜拭子和粪便样本中的病毒在基因上非常相似。因此，在AHC暴发期间，粪便样本也应被视为CVA24v常规分子诊断和分子流行病学研究的可靠替代样本类型。
