Final answer:
To decrease the risk of ocular complications in a patient with measles, the most important intervention is to avoid direct eye contact with discharges from herpetic lesions and to maintain good hygiene. Additionally, vitamin A supplementation following WHO guidelines can significantly help.
Step-by-step explanation:
The most important intervention in decreasing the risk of ocular complications in a patient with measles is to prevent direct eye contact with discharge from herpetic lesions elsewhere in the body or from another infected individual. This is because the herpes virus can cause serious eye infections in addition to the complications associated with measles. Ensuring that strict hygienic measures are enforced, and that the patient avoids touching their eyes after making contact with lesions, is critical.
Moreover, providing vitamin A supplementation can be a valuable strategy in reducing ocular complications and severity of the disease, as vitamin A deficiency is linked to increased susceptibility to severe measles and its ocular complications. Administering proper dosage of vitamin A should be done in accordance with the World Health Organization (WHO) guidelines for measles treatment.