Department of Public Health and Infectious Diseases, University of Rome Sapienza, Rome, Italy and Azienda Ospedaliero Universitaria Policlinico Umberto I, 00161 Rome, Italy.
Unit of Medical Statistics and Molecular Epidemiology, Università Campus Bio-Medico di Roma, 00128 Rome, Italy.
Viruses. 2024 Aug 24;16(9):1352. doi: 10.3390/v16091352.
Despite Parvovirus B19 (B19V) generally causing mild or asymptomatic infections, and only certain high-risk groups such as hematological or immunocompromised patients and pregnant women tending to develop complications, several factors challenge the assumption of a "benign" clinical course in immunocompetent adults and adolescents. A significant proportion of the population may harbor undiagnosed health conditions or genetic predispositions that could render them more susceptible to severe B19V complications. These could include mild hematological disorders, immune dysregulation not resulting in overt immunodeficiency, or underlying cardiac conditions. Concurrent infections with other pathogens, even seemingly minor ones, could synergistically increase the severity of B19V infection, leading to more pronounced clinical manifestations. While not definitively proven, the possibility of emerging B19V strains with increased virulence or altered tissue tropism cannot be entirely discounted. Additionally, the period of pandemic-related restrictions likely led to reduced B19V circulation, potentially resulting in a cohort of young adults with limited natural immunity, making them more vulnerable to infection. Potential clinical consequences include atypical and severe presentations, even in individuals without known risk factors. The traditional focus on B19V primarily as a pediatric concern might lead to underdiagnosis or delayed diagnosis in adults, potentially hindering timely intervention and management. A surge in B19V-related complications, even if individually mild, could collectively strain healthcare resources, particularly in settings with limited capacity or pre-existing pressures. Possible recommendations are to heighten clinical awareness with a high index of suspicion for B19V infection in adults and adolescents presenting with compatible symptoms, even in the absence of classic risk factors. Additionally, expanding testing criteria and enhancing public health surveillance efforts would be prudent.
尽管细小病毒 B19（B19V）通常引起轻度或无症状感染，只有某些高危人群如血液学或免疫功能低下的患者和孕妇容易出现并发症，但有几个因素挑战了免疫功能正常的成年人和青少年具有“良性”临床病程的假设。相当一部分人群可能存在未确诊的健康状况或遗传易感性，使他们更容易发生严重的 B19V 并发症。这些因素可能包括轻微的血液学障碍、未导致明显免疫缺陷的免疫失调，或潜在的心脏疾病。与其他病原体的同时感染，即使是看似轻微的感染，也可能协同增加 B19V 感染的严重程度，导致更明显的临床表现。虽然尚未得到明确证实，但不能完全排除具有更高毒力或改变组织嗜性的新兴 B19V 株的可能性。此外，与大流行相关的限制期可能导致 B19V 循环减少，可能导致一群年轻成年人自然免疫力有限，使他们更容易感染。潜在的临床后果包括非典型和严重表现，即使在没有已知危险因素的个体中也是如此。传统上主要将 B19V 视为儿科关注的焦点，可能导致成年人的诊断不足或延迟诊断，从而可能阻碍及时的干预和管理。即使个体的 B19V 相关并发症轻微，但如果集中出现，也可能会对医疗资源造成压力，特别是在资源有限或存在先前压力的环境中。可能的建议是提高临床意识，对出现符合症状的成年人和青少年的 B19V 感染保持高度怀疑，即使没有经典的危险因素。此外，扩大检测标准和加强公共卫生监测工作将是明智之举。
