Researchers in Bangladesh have identified a bat-borne virus, Pteropine orthoreovirus, in five patients initially suspected of Nipah virus infection. All patients had recently consumed raw date palm sap, a known transmission route for bat-related diseases. The discovery highlights the need for broader surveillance of emerging zoonotic threats.
In a study published in Emerging Infectious Diseases, scientists uncovered Pteropine orthoreovirus (PRV) in throat swab samples and virus cultures from five patients hospitalized between December 2022 and March 2023. These individuals presented symptoms typical of Nipah virus, such as fever, vomiting, headache, fatigue, increased salivation, and neurological issues, but tested negative for Nipah via PCR and serology.
The patients were part of a Nipah virus surveillance program run by the Institute of Epidemiology, Disease Control and Research (IEDCR) in Bangladesh, the International Centre for Diarrheal Disease Research, Bangladesh (icddr,b), and the U.S. Centers for Disease Control and Prevention (CDC). Using high-throughput viral capture sequencing (VCS), a method developed at Columbia University's Center for Infection and Immunity, researchers detected PRV genetic material. In three cases, they successfully cultured the live virus, confirming active infections.
All five patients had consumed raw date palm sap shortly before falling ill, a practice common in winter Bangladesh where bats often contaminate the sap. Bats serve as natural hosts for numerous zoonotic viruses, including Nipah, rabies, Hendra, Marburg, and SARS-CoV-1.
"Our findings show that the risk of disease associated with raw date palm sap consumption extends beyond Nipah virus," stated Nischay Mishra, PhD, associate professor of epidemiology at Columbia University Mailman School of Public Health and senior author of the study. "It also underscores the importance of broad-spectrum surveillance programs to identify and mitigate public health risks from emerging bat-borne viruses."
While PRV infections in nearby countries tend to be milder, the severe cases in Bangladesh suggest undiagnosed milder instances may exist. Recent work identified genetically similar PRV in bats near the Padma River Basin, linking animal reservoirs to human spillover.
"This [research] provides critical evidence linking bat reservoirs to human infection," said Ariful Islam, bat-borne disease ecologist at Charles Sturt University and co-first author. The study, co-led by Sharmin Sultana of IEDCR, was funded by the U.S. Department of Agriculture.
Tahmina Shirin, PhD, Director of IEDCR, noted: "A new addition of zoonotic spillover causes respiratory and neurological complications following consumption of raw date palm sap next to Nipah virus infection."
