CD4 therefore remains the gold standard for assessing disease progression and the need for the more intensive model of care for people with advanced HIV disease defined in the 2017 WHO guidelines, including screening, prophylaxis or treatment for major opportunistic infections (e.g., tuberculosis and cryptococcal meningitis), rapid antiretroviral therapy (ART) initiation, and intensified adherence counseling [13]. Here, CD4 is linked to Opportunistic infection.