In the past few days, I have seen a case of rabies in the United States caused by bats, which is also the first case of post-exposure disposal (PEP) failure and patient death in the United States after the use of cellular matrix rabies vaccine. Since there are few voices on bat rabies prevention and control in China, I share this information here, and I hope that everyone can pay attention to the risk of rabies exposed to bats. (Emphasis: extreme cases, no need to be frightened)
·Disposal after bat injury·
Bats, credit: Pexels
On July 27, 2020, in Minnesota, an 84-year-old man who had been sleeping suddenly woke up - a bat bit his right hand!
Since then, the man found that there were "no obvious wounds" on his hands, but he still washed his hands with soap and water, did not carry out rabies exposure disposal on the same day, and did not use neither vaccination nor passive immunization preparations.
Three days later, on July 30, the Minnesota Department of Health discovered that the bat was infected with the rabies virus, so the man went to the hospital emergency department that day to receive the rabies vaccine (days 0, 4, and 11), and used "rabies immune globulin" to infiltrate the wound periphery, and the rest of the protein was injected into the thigh.
And considering that his wife lives with him, there may also be undetected exposures, so she was vaccinated and immunized like her husband.
·Failure to dispose of after exposure·
After completing a series of post-exposure treatments, there is generally no need to worry about the risk of rabies.
However, on January 7, 2021, the man, "after 5 months of exposure to bats", developed strange symptoms: pain in the right side of his face, and very much tearing, while the initial diagnosis given by the hospital was trigeminal neuralgia or temporal arteritis, and he was discharged after prescribing the drug.
Since then, the man has gone to the hospital for various examinations and treatments without improvement, and developed facial paresthesia, dysphagia, bilateral shoulder-arm myalgia, right arm paresthesia, nausea and vomiting, and was admitted to hospital on 14 January to find dysarthria, night sweats, redness and discomfort in the right eye, right facial paralysis and left ear pain.
Although the clinical team suspected that the man's condition was related to rabies, because the patient had previously undergone "timely and standardized" post-exposure management, doctors could only suspect other causes, such as infections, immune diseases, or paraneoplastic syndromes.
On 22 January (15 days after symptom onset), the patient died, and a premortem CSF examination revealed encephalitis and had been feverish. The hospital sent clinical samples to the CDC for examination and determined that the patient was infected with rabies virus and did not produce "neutralizing antibodies" against rabies virus in the body after vaccination due to "immunodeficiency".
·Extreme cases that break the rules·
Rabies virus antigen, source cdc.gov
Why is a case of rabies so much attention? Because this case breaks multiple histories.
According to the World Health Organization, timely post-exposure disposal after severe exposure (generally tertiary exposure) "avoids 100% of rabies"; In the United States, "no one" has ever died after exposure using a rabies vaccine prepared from a cellular matrix; Of all the cases of post-exposure disposal failure between 1980 and 2022, none were "caused by exposure to bat rabies virus".
So why is this the case? It is very likely that the cause is related to the patient himself.
During the examination, it was found that the patient was not only of advanced age, but also had previously undiagnosed prostate cancer (bone metastases); The failure to produce neutralizing antibodies against rabies virus after vaccination may be due to the presence of monoclonal immunoglobulinemia (MGUS) secondary to prostate cancer, which is a factor affecting seroconversion after vaccination.
Although immune impairment is rarely associated with failure of post-exposure management of rabies (after all, failure is rare), it may also be associated with insufficient reporting, so researchers believe that exposure to immunocompromised individuals should consider several points:
(1) Detect antibody levels;
(2) post-exposure disposal as soon as possible (unlike in the case, the patient waited for the health bureau to confirm that the bat was infected with the virus);
(3) Give additional post-exposure disposal (such as additional immunoglobulins).
In short, internal causes may be related to the patient's own immune system, while external causes are post-exposure disposal that remains to be refined.
Bat rabies not to be underestimated ·
Beware of bats, credit: Pexels
Since bats are also hosts for rabies virus, exposure to bats also carries a risk of contracting and developing rabies virus.
Some people may think that exposure to bats is rare, or that the rabies virus associated with bats is rare, but this is wrong! In fact, many rabies virus variants have bats in their names, including: Australian bat risa virus, European bat risa virus type 1 and 2, ganoruwa bat lisa virus, Lagos bat lisa virus, Lleida bat lisa virus, Matlló bat lisa virus, Lleida bat lisa virus, simoni bat lisa virus, taiwanese bat lisa virus, western caucasian bat lisa virus...
Therefore, do not underestimate the risk of rabies virus infection from exposure to bats, and must go for post-exposure disposal as soon as possible after close contact with the virus!
Locations that can be disposed of include: canine injury clinics, (partially) hospital emergency surgery.
If you are not sure which of the above medical institutions with disposal capabilities in your local area, consult the local CDC or call 114 for consultation at the first time, do not delay! Don't wait! Don't bet!
May the world be free of epidemics
-Pill-