Antemortem diagnosis of human rabies in a veterinarian infected when handling a herbivore in Minas Gerais, Brazil

Abstract

SUMMARYThe Ministry of Health's National Human Rabies Control Program advocates pre-exposure prophylaxis (PEP) for professionals involved with animals that are at risk of contracting rabies. We report an antemortem and postmortem diagnosis of rabies in a veterinarian who became infected when handling herbivores with rabies. The antemortem diagnosis was carried out with a saliva sample and a biopsy of hair follicles using molecular biology techniques, while the postmortem diagnosis used a brain sample and conventional techniques. The veterinarian had collected samples to diagnose rabies in suspect herbivores (bovines and caprines) that were subsequently confirmed to be positive in laboratory tests. After onset of classic rabies symptoms, saliva and hair follicles were collected and used for antemortem diagnostic tests and found to be positive by RT-PCR. Genetic sequencing showed that the infection was caused by variant 3 (Desmodus rotundus), a finding confirmed by tests on the brain sample. It is essential that professionals who are at risk of infection by the rabies virus undergo pre-exposure prophylaxis. This study also confirms that molecular biology techniques were used successfully for antemortem diagnosis and therefore not only allow therapeutic methods to be developed, but also enable the source of infection in human rabies cases to be identified accurately and quickly.

Rhabdovirus: Rabies

“…Human antemortem diagnosis can be made by virus isolation from saliva, antigen detection in biopsy tissue, or demonstration of virus-specifi c antibody (without prior vaccination). Selected FA tests are performed on human brain or skin biopsies, the latter usually taken from highly innervated areas, such as the nape of the neck, where piloerector nerve plexi are prominent [ 42 ]. Also, in some human rabies cases, corneal cells obtained from touch impressions may be antigenpositive during life, care being taken not to abrade the delicate corneal tissue (a rationale to caution against this method vs. other stated procedures).…”

Murciélagos hematófagos como reservorios de la rabia

“…En la investigación epidemioló-gica de los casos se constató una posible transmisión secundaria, pues ambas personas tuvieron antecedente de mordedura de gato que presentaba alteraciones de comportamiento (31) . En Quilichao, Colombia en el año 2008 fueron registrados dos casos de rabia en niños que fueron mordidos por un gato, la tipificación antigéni-ca confirmó variante (AgV3) (32) . (33) .…”

Epidemiology

“…There is little documentation for natural rabies transmission by simple contact with virus-infected tissue, although isolated reports suggest infection following butchering of infected carcasses, (Anonymous, 2004;Tariq, Shafi, Jamal, & Ahmad, 1991;Noah et al, 1998) and recently an unvaccinated veterinarian using no personal protective equipment (i.e., gloves, eye protection, etc.) prepared a domestic herbivore for submission for rabies testing and later succumbed to rabies (Brito et al, 2011). In the United States, ingestion of unpasteurized milk from rabid cows has been considered a possible exposure to virus (Centers for Disease Control and Prevention, 1999).…”

“…These species frequently are not vaccinated against rabies. At least one human death has been documented as a result of contact with a rabid domestic herbivore in Brazil (Brito et al, 2011). Mass human exposures have occurred where animals in public settings developed rabies.…”