Opportunistic infection is caused by pathogens which are Viruses Bacteria Fungi Protozoa When autoimmune system is weakened, the main causes are Immunodeficiency or immunosuppression Malnutrition Fatigue Recurrent infection Advanced HIV infection Chemotherapy or cancer Genetic Skin damage Prolonged antibiotic therapy Medical procedures Pregnancy Ageing Leukopenia types of infections Aspergillus Candida Actinomycosis Blastomycosis Histoplasmosis Sporotrichosis Coccidiomycosis toxoplasma gondii Staphylococcus aureus Streptococcus phenomena Haemophilus influenzae E. coli And many ocular manifestations of these are  Pneumocystis Carinii choroidopathy Toxoplasmic chorioretinitis Retinal necrosis 70 percent cases of are CH lead to retinal detachment Candida endophthalmitis Recurrent HZ ophthalmics and Recurrent dendritic corneal ulceration in a young person Share your opinion.