The correct answer is C. Single stranded RNA. )
Explanation: The image, along with the vignette, describes Hand-foot-and-mouth (HFM) disease (see image Figure 3.10.4 and Table 3.10.1 in DIR). The causative agent is coxsackievirus A16, A6 which is a ssRNA picornavirus. This rash starts out as macules that progress to vesicles/pustules on the hands, feet, groin, and mucosa. Other symptoms include fever, anorexia, malaise, abdominal pain, myocarditis, pneumonia, and encephalitis. This condition usually resolves in 1 week, but the A6 variant can present with more severe blistering and widespread disease.
Wrong answer explanation:
- ssDNA viruses are not a common cause of HFM
- dsDNA viruses are not a common cause of HFM
- ssRNA is the correct answer
- dsRNA viruses are not a common cause of HFM
- Retroviruses are not a common cause of HFM
References: Pediatric Dermatology chapter, 3.10 Exanthematous Diseases of Childhood, DIR Review book page 208 2020.