First breakthrough rabies infection in US reported in immunocompromised man
Click Here to Manage Email Alerts
Key takeaways:
- This is the first breakthrough rabies infection despite appropriate PEP in the U.S.
- The patient had an underlying immunocompromising condition that likely prevented proper response to the rabies vaccines.
An 84-year-old man reportedly died from rabies 6 months after being bitten by a bat and receiving timely rabies post-exposure prophylaxis.
Researchers said this likely happened because of an underlying immunocompromising condition.
“This study was conducted to understand the underlying cause for a deadly rabies infection in a person who received timely and appropriate rabies vaccination and wound care following a recognized exposure to a rabid bat,” Caroline A. Schrodt, MD, MSPH, lieutenant commander of the U.S. Public Health Service, told Healio.
“Called post-exposure prophylaxis (PEP), this combination of vaccine and antibody therapy is highly effective at preventing [the] clinical onset of rabies,” Schrodt said.
According to the study, the patient, an 84-year-old man in Minnesota — who had a history of coronary artery disease with prior coronary artery bypass and automatic defibrillator placement, controlled type 2 diabetes mellitus, hypertension, hyperlipidemia, chronic kidney disease and benign prostatic hyperplasia — was woken up by a bat biting his right hand on July 27, 2020.
The bat tested positive for rabies, prompting PEP initiation. The man received a dose of human rabies immune globulin on July 30, followed by three additional doses 3, 7 and 14 days after the first dose — a recommendation made for previously unvaccinated, immunocompetent people.
Roughly 5 months later, on Jan. 7, 2021, the patient developed severe pain on the right side of his face and excessive eye watering. On January 9, he presented with an elevated erythrocyte sedimentation rate and was discharged with oxycodone, carbamazepine and corticosteroids for suspected trigeminal neuralgia or temporal arteritis.
His symptoms persisted, however, and he returned to the ED on January 13 with facial paresthesia, dysphagia, bilateral shoulder and arm muscle pain, right arm paresthesia, nausea and vomiting. He was then hospitalized on January 14 with worsening facial pain and paresthesia, generalized weakness and decreased oral intake.
His medical team considered rabies because of the clinical presentation and confirmed exposure but still explored other infections and conditions as is customary before pursuing rabies diagnostic testing. Symptoms persisted, and the patient developed a fever and was ultimately intubated. Supportive care was withdrawn, and he died on January 22.
Using premortem specimen, the CDC confirmed rabies infection on January 26.
Schrodt explained that this case is the first known breakthrough infection reported in a person who received appropriate PEP since the development of modern rabies vaccines in the U.S.
“Given the rarity of this situation and fatal outcome, an investigation was conducted to ensure the efficacy of rabies biologicals used in the U.S. and determine a cause for the suspected vaccination failure,” she said.
Schrodt and colleagues reviewed the patient’s medical records, laboratory results and autopsy findings, and performed whole-genome sequencing (WGS) to compare patient and bat virus sequences. According to the study, they also conducted risk assessments for people who were also potentially exposed to the bat and for close contacts of the deceased patient.
From their review, the researchers learned that rabies virus antibodies were present in serum and cerebrospinal fluid and were non-neutralizing, while blood testing done before the patient’s death revealed that he had unrecognized monoclonal gammopathy of “unknown significance.” After reviewing his autopsy, the researchers found rabies meningoencephalitis and metastatic prostatic adenocarcinoma.
Through WGS, the team confirmed that the patient and the bat from the bite in July 2020 had identical rabies virus sequences, meaning the infection was from that initial contact with the bat. Of 332 additional people assessed for potential rabies exposure to the case patient, three warranted PEP and were treated.
“While this is a tragic case, it does not challenge the safety or efficacy of modern rabies vaccines, which are one of the most effective vaccines available,” Schrodt said.
She added that clinicians administering rabies PEP should perform a full review of systems, and if an immunocompromising condition is identified or suspected, clinical management should include checking for an appropriate response to vaccination. Public health authorities should then advise on additional vaccines or treatment if antibody levels are insufficient.
“Given the high-consequence nature of rabies virus infections, any suspected vaccine failures should be thoroughly investigated to ensure there is confidence in the rabies vaccines and immunoglobulin and to ensure there is not a wider risk to the 60,000 people per year that have a suspected rabies exposure in the U.S.,” Schrodt said.
Collapse
Read more about
Click Here to Manage Email Alerts