Paralytic #rabies #outbreak mimicking #GBS in French #Amazonia

 

Abstract

Background

In the Amazonian region, vampire bats are the primary reservoir of rabies virus, causing sporadic and lethal human rabies cases that often remain unnoticed. Managing human cases in this region is challenging and further complicated by atypical clinical forms and the potential exposure to various toxic compounds, particularly among gold miners.

Methods

We carried out clinical, electrical, biological and histological analysis of concurrent cases of progressive motor neuronopathy and fatal encephalitis in a context of regular exposure to bat bites of gold miners living in a small and remote gold mine camp in Amazonia, in French Guiana, South America.

Findings

We analyzed a spatio-temporal cluster of three suspected rabies cases in 2024 with a fatal outcome, with concomitant onset of acute bilateral lower-limb paralysis without demyelination, two of which occurred presumably two weeks after a bat-bite. Electroneuromyography suggested the involvement of the anterior horn of the spinal cord, as described in furious forms of rabies. None of the cases exhibited other cardinal signs of the furious form. Confirmation of rabies was obtained for them on sera and brain biopsies collected ante- and post-mortem respectively.

Interpretation

The concurrent occurrence of disease, the axonal motor neuropathy mimicking the motor form of Guillain Barré syndrome in the context of paralytic rabies, lead to diagnostic-wandering. This underscores the importance of thinking about vampire bat rabies virus in the presence of any atypical neurological picture in patients living in exposed areas in Latin America.

Source: 

Link: https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0014149

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Post-exposure #prophylaxis regimen of #rabies monoclonal #antibody and #vaccine in category 3 potential exposure patients ...

 

Summary

Background

Rabies is almost invariably fatal. A rabies monoclonal antibody (RmAb) was approved in India in 2016 for passive prophylaxis. This post-marketing study aimed to evaluate the long-term safety, immunogenicity, and efficacy of a post-exposure prophylaxis (PEP) regimen containing RmAb.

Methods

This phase 4, open-label, randomised, active-controlled study was conducted at 15 tertiary care hospitals in India. Patients aged 2 years or older with WHO category 3 rabies exposure by a suspected rabid animal were eligible if the exposure occurred less than 72 h before enrolment, or less than 24 h before enrolment for exposures to the face, neck, hand, or fingers. Participants were randomly assigned (3:1) to receive either RmAb (Rabishield; Serum Institute of India, Pune, India) plus a purified Vero cell rabies vaccine (PVRV; Rabivax-S) or equine rabies immunoglobulin (ERIG; Equirab) plus PVRV as PEP. In each treatment group, patients were further randomly assigned (1:1) to receive PVRV either intradermally or intramuscularly. Study group allocation was done using a permuted block design with random block sizes of eight. A central randomisation list was generated before the study start and randomisation was performed with an interactive web response system. Participants and site personnel were not masked to group assignment. RmAb (3·33 IU/kg) and ERIG (40 IU/kg) were infiltrated into and around the wounds only on day 0 as per WHO 2018 recommendations. PVRV was administered 1·0 mL intramuscularly (days 0, 3, 7, 14, and 28) or 0·1 mL plus 0·1 mL intradermally (days 0, 3, 7, and 28). The primary outcome was treatment-related serious adverse events up to 365 days after immunisation, analysed in the safety analysis set (all participants who received at least one dose of vaccine with treatment). Geometric mean concentrations of rabies virus neutralising antibody were measured in a subset of patients. This study is registered with Clinical Trial Registry–India (CTRI/2019/06/019622) and is completed.

Findings

4059 participants were enrolled between Aug 21, 2019, and March 31, 2022, and randomly assigned. A total of 3994 participants (3001 male, 993 female) were treated (2996 RmAb plus PVRV, 998 ERIG plus PVRV), of which 3622 (90·7%) participants completed the 1-year follow-up. 11 adverse events were considered causally related to RmAb plus PVRV and 17 were considered causally related to the ERIG plus PVRV regimen. Most adverse events were mild and transient. Seven serious adverse events occurred in the RmAb group and all were causally unrelated. One causally related serious adverse event was reported in the ERIG group. On day 14, the geometric mean concentrations increased to 16·05 IU/mL (95% CI 13·25–19·44) in the RmAb group and 13·48 IU/mL (9·51–19·11) in the ERIG group (point estimate 1·19 [95% CI 0·82–1·72]). No patient developed rabies during the 1-year follow-up period.

Interpretation

RmAb was safe and well tolerated and showed protective efficacy against rabies. A PEP regimen containing RmAb plus PVRV was immunogenic with long-term persistence of immune response.

Funding

Serum Institute of India.

Source: Lancet, https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(25)00735-4/abstract?rss=yes

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#Rabies - #Timor-Leste (#WHO D.O.N., July 24 '25)

 

{Summary}

Situation at a glance

On 17 May 2025, the Timor-Leste government reported to the World Health Organization (WHO) a fatal human case of rabies from Ermera Municipality. 

Between May and mid-June 2025, Timor-Leste confirmed four human rabies deaths in the municipalities of Bobonaro (n=2), Ermera (n=1) and Oecusse (n=1). 

All cases involved individuals exposed to dogs' bites months prior to symptom onset, with rabies virus confirmed via Reverse Transcription Polymerase Chain Reaction (RT-PCR) testing. 

Since March 2024, a total of 106 animal rabies cases—mostly in dogs—have been reported, and over 1400 dog bites or scratches have occurred, with a total of six fatalities. 

Access to and completion of post-exposure prophylaxis remains limited. 

The spread of rabies into non-border areas like Ermera signals a growing public health concern. 

The public health response is ongoing and includes vaccination of dogs, risk communication, training of healthcare workers on Post-Exposure Prophylaxis (PEP) and case management, active surveillance, and ensuring the availability of rabies vaccines and human rabies immunoglobulin. 

Based on the current available information, the WHO assesses the risk posed by this event as high at the national level, moderate at the regional level, and low at the global level.

(...)

Source: World Health Organization, https://www.who.int/emergencies/disease-outbreak-news/item/2025-DON576

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Genomic and #Clinical #Analysis of a #Fatal Human #Lyssavirus irkut Case: Evidence for a Natural Focus in the Russian Far East

Abstract

In this report, we document and analyze a case in which the Irkut virus (IRKV) (Mononegavirales: Rhabdoviridae) caused a fatal human case following a bat bite in June 2021. Unfortunately, the available data did not permit a detailed taxonomic classification of the carrier bat (Chiroptera). The event occurred in the southwestern part of the Sikhote-Alin mountain region (Russian Far East) covered by the Ussuri taiga forest. The symptoms of the illness began with the following: fever; pronounced psychomotor and motor agitation; tremor of the lower jaw and tongue; aphasia; dyslexia; and dysphagia. These rapidly developed, leading to a severe and fatal encephalitis. The patient was not vaccinated for rabies and did not receive rabies immunoglobulin. Using brain sections prepared from the deceased, molecular diagnostics were performed: immunofluorescence (polyclonal anti-rabies immunoglobulin) indicating the presence of the lyssavirus antigen; and RT-PCR indicating traces of viral RNA. Sectional material (brain) was used for whole-genome sequencing, resulting in a near-complete sequence of the lyssavirus genome. The obtained genomic sequence was identified as the Irkut virus. A comparative analysis of the new sequence and other currently available IRKV sequences (NCBI) revealed differences. Specifically, amino acid differences between antigenic sites in the isolate and those of the rabies vaccine strain used regionally were noted. The patient history and subsequent analysis confirm human IRKV infection following bat contact. Like other fatal cases of IRKV infection described earlier, this case occurred in the southern part of the Russian Far East. Two have occurred in the southwestern part of the Sikhote-Alin mountain region. This indicates the possible existence of an active, natural viral focus.

Source: Viruses, https://www.mdpi.com/1999-4915/17/6/769

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