Emerging bat virus found in stored throat swabs from 5 patients with suspected Nipah virus infection

A cluster of five unrelated individuals exhibiting a range of severe symptoms – including fever, disorientation, altered mental status, abnormal gait, and difficulty breathing – has prompted investigation into potential viral causes beyond previously known risks. One pediatric patient experienced fever-related convulsions. The cases, which did not involve individuals who knew each other, raise concerns about emerging zoonotic diseases and the need for broader diagnostic considerations.

New Findings Expand Understanding of Potential Risks

Researchers have found that the risk of disease associated with consuming raw date palm sap extends beyond the previously recognised threat of the NiV virus. Two patients fully recovered after hospital release, two to three weeks after admission, but two continue to experience lingering fatigue, disorientation, and difficulties with breathing and walking. Tragically, one patient died in August 2024 after a period of declining health and unexplained neurological issues.

Did You Know? Certain segments of the virus’s double-stranded RNA genomes clustered with viruses isolated from fruit bats in Indonesia and Malaysia.

Viral Reassortment and Evolution

Analysis of the virus’s genetic makeup revealed a high degree of similarity – 91.1% to 100% – across all 10 segments of the Bangladesh PRV. However, the genetic data also suggests a unique evolutionary path, with segments clustering with viruses found in fruit bats and, less frequently, in humans in Southeast Asia. This indicates the potential for reassortment events, a process where viruses exchange genetic material, potentially altering their transmissibility and virulence.

“The potential for reassortment in segmented viruses like PRV can result in changes in transmissibility and virulence,” researchers stated. The authors suggest that long flight ranges of fruit bats may contribute to the spread of these viruses.

Expert Insight: The identification of viral reassortment highlights the dynamic nature of zoonotic viruses and the potential for unexpected outbreaks. The ability of viruses to exchange genetic material underscores the importance of ongoing surveillance and research to understand emerging threats.

Given the similarities in symptoms between PRV and NiV, and their shared link to the consumption of raw date palm sap contaminated with bat droppings, researchers recommend that healthcare providers consider PRV in their diagnostic assessments.

Frequently Asked Questions

What symptoms were observed in the patients?

The five patients exhibited fever, disorientation, altered mental status, abnormal gait, and difficulty breathing. One pediatric patient also experienced fever-related convulsions.

What is viral reassortment?

Viral reassortment is a process where segmented viruses, like PRV, exchange genetic material, potentially leading to changes in how easily they spread and how severe the illness they cause can be.

What do the researchers recommend for healthcare providers?

Researchers recommend that healthcare providers include PRV in their differential diagnosis, particularly in areas where raw date palm sap is consumed, and consider molecular and serologic surveillance.

As surveillance efforts continue and more data becomes available, it will be important to monitor for any changes in the virus’s behavior and to assess the potential for further spread. A possible next step could be expanded testing of date palm sap to determine the prevalence of the virus.