The World Health Organization (WHO) has issued a serious warning regarding the Middle East respiratory syndrome coronavirus (MERS-CoV) following a rise in reported cases. As of December 21, 2025, the WHO confirmed a total of 19 cases, leading to four fatalities. Of these cases, 17 were identified in Saudi Arabia, while two were reported in France. This heightened alert comes amidst a global surge in adenovirus infections, prompting health professionals to advise both adults and children to remain vigilant for symptoms associated with respiratory illnesses.
In its recent update, the WHO noted that between June 4 and December 21, 2025, the Ministry of Health (MoH) of Saudi Arabia reported seven cases of MERS-CoV infection, including two deaths. While the overall risk assessment remains moderate at both global and regional levels, these cases underscore the continuing threat posed by the virus in certain regions. MERS-CoV is primarily known to infect dromedary camels, with sporadic spillover events leading to human infections.
Emerging Concerns Over New Bat-Borne Coronavirus
Adding to the anxiety surrounding respiratory viruses, researchers recently discovered a new bat-borne coronavirus in Brazil. While the implications of this virus for human health remain unclear, it has raised alarms among experts. The new coronavirus displays significant similarities to the MERS virus initially detected in 2012 in Saudi Arabia, which has been responsible for over 850 fatalities worldwide.
PhD candidate Bruna Stefanie from São Paulo and Ceará collaborated with scholars from Hong Kong University (HKU) to study this novel virus. The research, published in the Journal of Medical Virology (JMV), involved an extensive examination of 423 bats from 16 different species. Researchers collected oral and rectal samples, ultimately identifying the new coronavirus in an insect-eating bat.
Stefanie explained, “Right now we aren’t sure it can infect humans, but we detected parts of the virus’s spike protein, which binds to mammalian cells to start an infection, suggesting potential interaction with the receptor used by MERS-CoV.” The study found that the newly discovered coronavirus shares 72% genetic similarity with the MERS-CoV genome. More concerning, the spike protein exhibited a 71.74% similarity to that of the MERS virus, indicating a potential risk for future human infections.
Symptoms of MERS-CoV include fever, coughing, shortness of breath, diarrhea, and vomiting, with severe cases leading to fatalities. Currently, there is no vaccine available for MERS, highlighting the urgent need for ongoing surveillance and research in this area.
As health authorities around the world monitor these developments closely, the emergence of both MERS-CoV cases and the newly identified bat coronavirus serve as a reminder of the persistent threats posed by respiratory viruses. Public health officials continue to call for increased awareness and preparedness to mitigate potential outbreaks.
