An Overview of Eastern Equine Encephalitis (EEE)

Emerging and Novel Viruses in Passerine Birds

There is growing interest in emerging viruses that can cause serious or lethal disease in humans and animals. The proliferation of cloacal virome studies, mainly focused on poultry and other domestic birds, reveals a wide variety of viruses, although their pathogenic significance is currently uncertain. Analysis of viruses detected in wild birds is complex and often biased towards waterfowl because of the obvious interest in avian influenza or other zoonotic viruses. Less is known about the viruses present in the order Passeriformes, which comprises approximately 60% of extant bird species. This review aims to compile the most significant contributions on the DNA/RNA viruses affecting passerines, from traditional and metagenomic studies. It highlights that most passerine species have never been sampled. Especially the RNA viruses from Flaviviridae, Orthomyxoviridae and Togaviridae are considered emerging because of increased incidence or avian mortality/morbidity, spread to new geographical areas or hosts and their zoonotic risk. Arguably poxvirus, and perhaps other virus groups, could also be considered "emerging viruses". However, many of these viruses have only recently been described in passerines using metagenomics and their role in the ecosystem is unknown. Finally, it is noteworthy that only one third of the viruses affecting passerines have been officially recognized.

Eastern Equine Encephalitis: Case Series in Southern New England and Review of the Literature

Purpose of Review

To describe the clinical presentation, diagnosis, management, and outcomes of 4 confirmed Eastern equine encephalitis (EEE) cases and a review of the literature.

Recent Findings

There was a sharp rise in the number of EEE cases in the United States in 2019, with 38 confirmed cases and 15 deaths. Our institution cared for 10% of patients with neuroinvasive EEE nationwide. These were the first cases seen locally since 2010.

Summary

EEE virus causes one of the most lethal types of arboviral encephalitis in the United States with a mortality of 30%-40%. Manifestations of EEE infections can range from mild encephalopathy to coma. Common findings include CSF pleocytosis and involvement of the basal ganglia on MRI. Given the rarity of this disease and nonspecific findings, diagnosis can be challenging, and a high clinical suspicion is important. Management is mainly supportive, and the use of IV immunoglobulin remains controversial. Two of our 4 patients died; these patients had coma within 48 hours, hyponatremia, involvement of bilateral thalami and brainstem, status epilepticus, and severe brain dysfunction in EEG.