Final answer:
Providing emotional support and reassurance is the best initial intervention by a nurse for a client newly diagnosed with HIV, followed by education about the disease and treatment options.
Step-by-step explanation:
The best intervention by the nurse for a client with a new diagnosis of HIV would be to provide emotional support and reassurance. It is crucial to offer an empathetic ear and understanding as the initial step to address the emotional and psychological distress the client may be experiencing. Providing education about antiretroviral drugs and potential symptoms of HIV comes next, but this kind of information can be overwhelming for a patient who is still processing the diagnosis. Administering medications and facilitating support group meetings are also important, but the immediate need is to stabilize the client's emotional state before moving forward with these steps.