Conclusion
This study identified severe cases of haemorrhagic fever with renal syndrome (HFRS) with different epidemiological, clinical and laboratory characteristics. Meanwhile, hantavirus and Bunyavirus co-infection was confirmed by experimental verification in severe HRFS cases, suggesting that co-infection with viral haemorrhagic fever may affect the severity of the disease. The results of this study provide scientific reference and insights for the prevention, diagnosis and treatment of co-infection with viral haemorrhagic fever.