Final answer:
A facial rash spreading to extremities, combined with other symptoms such as low-grade fever, headache, conjunctivitis, cough, runny nose, and swollen lymph nodes, may lead a nurse to suspect that a toddler has rubella. .
Step-by-step explanation:
The clinical finding that would lead the nurse to suspect that a toddler with a rash has rubella is a facial rash spreading to extremities, followed by low-grade fever, headache, conjunctivitis, cough, runny nose, and swollen lymph nodes. In cases of congenital rubella, the rash may be accompanied by birth defects, miscarriage, or stillbirth. Rubella can be diagnosed by hemagglutinin inhibition assays and other immunological techniques. Although there is no specific antiviral therapy, an effective rubella vaccine (MMR) is available.