Characteristics and Clinical Management of a Cluster of 3 Patients With Ebola Virus Disease, Including the First Domestically Acquired Cases in the United States

Abstract

Background: More than 26,000 cases of Ebola virus disease (EVD) have been reported in western Africa, with high mortality. Several patients have been medically evacuated to hospitals in the United States and Europe. Detailed clinical data are limited on the clinical course and management of patients with EVD outside western Africa.

Objective: To describe the clinical characteristics and management of a cluster of patients with EVD, including the first cases of Ebola virus (EBOV) infection acquired in the United States.

Design: Retrospective clinical case series.

Setting: Three U.S. hospitals in September and October 2014.

Patients: First imported EVD case identified in the United States and 2 secondary EVD cases acquired in the United States in critical care nurses who cared for the index case patient.

Measurements: Clinical recovery, EBOV RNA level, resolution of Ebola viremia, survival with discharge from hospital, or death.

Results: The index patient had high EBOV RNA levels, developed respiratory and renal failure requiring critical care support, and died. Both patients with secondary EBOV infection had nonspecific signs and symptoms and developed moderate illness; EBOV RNA levels were moderate, and both patients recovered.

Limitation: Both surviving patients received uncontrolled treatment with multiple investigational agents, including convalescent plasma, which limits generalizability of the results.

Conclusion: Early diagnosis, prompt initiation of supportive medical care, and moderate clinical illness likely contributed to successful outcomes in both survivors. The inability to determine the potential benefit of investigational therapies and the effect of patient-specific factors that may have contributed to less severe illness highlight the need for controlled clinical studies of these interventions, especially in the setting of a high level of supportive medical care.

Primary funding source: None.

Figure 1. Clinical course of the index case and 2 secondary cases of Ebola virus disease

Dates of symptom and fever onset, investigational therapeutics administered, and key events in the hospital course for the 3 patients are shown. BCV = brincidofovir; CVVHD = continuous venovenous hemodialysis; ED = emergency department; ICU = intensive care unit; RT-PCR = reverse transcriptase polymerase chain reaction.

Figure 2. Timeline of laboratory results and treatments for patient 1

Trends in serum aminotransferase levels, platelet count, and leukocyte count are shown in the top graph. Horizontal dotted bars denote the periods during which investigational therapeutics were administered, with individual doses indicated in solid color within those periods. Decrease in blood EBOV RNA levels (as reflected by increase in Ct values) and appearance of IgM antibodies to EBOV (indicated as reciprocal titers) are shown in the bottom graph. This patient did not develop detectable IgG antibodies to EBOV. ALT = alanine aminotransferase; AST = aspartate aminotransferase; Ct = cycle threshold; EBOV = Ebola virus.

Figure 3. Timeline of laboratory results and treatments for patient 2

Trends in serum aminotransferase levels, platelet count, and leukocyte count are shown in the top graph. Horizontal dotted bars denote the periods during which investigational therapeutics were administered, with individual doses indicated in solid color within those periods. Decrease in blood EBOV RNA levels (as reflected by increase in Ct values) and appearance of antibodies to EBOV (indicated as reciprocal titers) are shown in the bottom graph. ALT = alanine aminotransferase; AST = aspartate aminotransferase; Ct = cycle threshold; EBOV = Ebola virus.

Figure 4. Timeline of laboratory results and treatments for patient 3

Trends in serum aminotransferase levels, platelet count, and leukocyte count are shown in the top graph. Horizontal dotted bars denote the periods during which investigational therapeutics were administered, with individual doses indicated in solid color within those periods. Decrease in blood EBOV RNA levels (as reflected by increase in Ct values) and appearance of antibodies to EBOV (indicated as reciprocal titers) are shown in the bottom graph. Suspected illness onset date was 10 October 2014; fever onset date was 14 October 2014. ALT = alanine aminotransferase; AST = aspartate aminotransferase; Ct = cycle threshold; EBOV = Ebola virus.