First Report of Respiratory Syncytial Virus and Human Metapneumovirus Co-Infection in a 2-Year-Old Kawasaki Patient in Iran

Shatizadeh Malekshahi, S; Mokhtari Azad, T; Shahmahmoodi, Sh; Yavarian, J; Rezaei, F; Naseri, M

In the present study, we demonstrated the possibility to detect dual infection which caused by RSV and hMPV. Due to the lack of sensitivity of conventional methods detection of co-infections with different respiratory viruses had been un-derestimated (13) . Severe RSV bronchiolitis in small patient series had been recognized because of co-infection with other viral pathogens (14) . Some previous studies have lighted up increased clinical severity in case of dual infection caused by RSV and hMPV (8, 9) . Greensill et al. observed a 70% co-infection rate with HMPV and RSV and a 90% co-infection rate among intubated infants with hMPV and RSV admitted to their PICU (8) . Although Greensill et al. did not include an appropriate control group in their study, these findings suggest that co-infection with both hMPV and RSV is common and that together the two viruses may contribute to increase the severity of disease (9, 14) . Whereas in other reports hMPV did not contribute to the severity of RSV infection (15, 16) . The basis of the pathogenesis of severe RSV disease is multifactorial. Since severe RSV disease may develop in apparently healthy children, known host risk factors cannot completely account for instances of severe illness. Preexisting or maternally acquired immunity, innate immunity, viral factors and genotypes and environment all likely contribute to disease pathogenesis. We detected co-infection of hMPV and RSV in Kawasaki patient without special respiratory sign and symptoms, we could not find the patient to follow up her and study more about the immunity status and other possibilities of this scenario. More investigation is suggested specially on Kawasaki patients to detect the viral pathogens.