Silent War to Emerging or Re-emerging Respiratory Infection Diseases Badly Kept in Mind

Zheng, Ya-Li; Gao, Zhan-Cheng

As a zoonotic disease, the exact way in which MERS-CoV transmits between different species is still unknown. Previous studies support that dromedary camels serve as the primary animal source and major reservoir, [4] while bats may be the ultimate reservoir of the virus. [5] But the time of initial infection in bat species and the way of the virus transmitted to camels have yet to be determined. Serological evidence shows that MERS-CoV has infected camels for at least 20 years, [6] whereas the virus appear to have spread from camels-to-humans in the early 2010s. [7] Camels-to-human transmission is through close contacts with camels or consumption of camel products. [4, 8] However, while camels appear as the likely source, other sources have not been ruled out. [9] For example, except the history of visit to the middle east, the index case of South Korea was confirmed with no close contact with camel, no health care facility visit history, and no camel products consumption history, according to the investigation of WHO. [10] There still could be another or some more common intermediate host exists.