Infectious eye diseases are a significant global health issue, affecting children and working-age individuals, often causing unilateral or asymmetric visual loss. These diseases include viral, bacterial, fungal, and parasitic infections, which together may account for a large portion of the global visual burden. Diagnosis is challenging, especially in specialist centers, and many conditions are highly regional. Globalization has made understanding transmission modes and geographic distribution crucial for clinicians. Current global prevalence studies on visual impairment and blindness focus on bilateral disease in the over-50s, neglecting unilateral conditions. Infectious eye diseases are often preventable and affect younger people, so they should be considered a separate category in future studies, including disability-adjusted life years (DALYs). Control of these diseases requires collaboration across various fields, including vaccination, antibiotic development, and environmental management. Global warming, conflict, and poverty may increase their impact. Telemedicine can aid diagnosis in resource-poor areas, but enhanced reporting and AI systems may be needed for surveillance. Infectious diseases like tuberculosis and measles disproportionately affect people from developing countries. Emerging infectious diseases, including arboviruses and zoonotic pathogens, have led to unexpected ocular pathologies. Correct diagnosis is critical for treatment and prevention. Many infectious eye diseases are unilateral and not captured in current prevalence studies. Monocular visual impairment is now recognized as a disability, and many infectious eye diseases affect all age groups, not just the over-50s. Conditions like toxoplasmosis are common and globally distributed, potentially leading to significant visual loss. The global burden of infectious eye diseases is likely underestimated due to these factors. Viral eye diseases include herpesviruses, adenoviruses, and others, with complications such as corneal scarring and retinal vascular occlusion. Vaccines can prevent some infections but may also cause ocular complications. Herpesviruses cause various pathologies, including retinal necrosis and blindness. Cytomegalovirus causes uveitis and retinitis, treatable with antiviral drugs. HIV-related ocular damage is due to opportunistic infections and immune recovery inflammatory syndromes. Measles can cause vitamin A deficiency, leading to severe ocular pathology. Rubella can cause congenital ocular issues, and dengue and chikungunya viruses can cause ocular complications. Zika virus can cause congenital malformations. Other viruses like Ebola and SARS-CoV-2 can cause severe ocular inflammation and visual loss. Bacterial and fungal infections, such as trachoma and onchocerciasis, are major causes of visual impairment. Trachoma is decreasing due to the SAFE strategy, but remains a significant burden in sub-Saharan Africa. Infectious keratitis is a leading cause of unilateral blindness, often due to bacteria, fungi, or viruses. Orbital cellulitis is a significant cause of visual morbidity and mortality, especially in children.Infectious eye diseases are a significant global health issue, affecting children and working-age individuals, often causing unilateral or asymmetric visual loss. These diseases include viral, bacterial, fungal, and parasitic infections, which together may account for a large portion of the global visual burden. Diagnosis is challenging, especially in specialist centers, and many conditions are highly regional. Globalization has made understanding transmission modes and geographic distribution crucial for clinicians. Current global prevalence studies on visual impairment and blindness focus on bilateral disease in the over-50s, neglecting unilateral conditions. Infectious eye diseases are often preventable and affect younger people, so they should be considered a separate category in future studies, including disability-adjusted life years (DALYs). Control of these diseases requires collaboration across various fields, including vaccination, antibiotic development, and environmental management. Global warming, conflict, and poverty may increase their impact. Telemedicine can aid diagnosis in resource-poor areas, but enhanced reporting and AI systems may be needed for surveillance. Infectious diseases like tuberculosis and measles disproportionately affect people from developing countries. Emerging infectious diseases, including arboviruses and zoonotic pathogens, have led to unexpected ocular pathologies. Correct diagnosis is critical for treatment and prevention. Many infectious eye diseases are unilateral and not captured in current prevalence studies. Monocular visual impairment is now recognized as a disability, and many infectious eye diseases affect all age groups, not just the over-50s. Conditions like toxoplasmosis are common and globally distributed, potentially leading to significant visual loss. The global burden of infectious eye diseases is likely underestimated due to these factors. Viral eye diseases include herpesviruses, adenoviruses, and others, with complications such as corneal scarring and retinal vascular occlusion. Vaccines can prevent some infections but may also cause ocular complications. Herpesviruses cause various pathologies, including retinal necrosis and blindness. Cytomegalovirus causes uveitis and retinitis, treatable with antiviral drugs. HIV-related ocular damage is due to opportunistic infections and immune recovery inflammatory syndromes. Measles can cause vitamin A deficiency, leading to severe ocular pathology. Rubella can cause congenital ocular issues, and dengue and chikungunya viruses can cause ocular complications. Zika virus can cause congenital malformations. Other viruses like Ebola and SARS-CoV-2 can cause severe ocular inflammation and visual loss. Bacterial and fungal infections, such as trachoma and onchocerciasis, are major causes of visual impairment. Trachoma is decreasing due to the SAFE strategy, but remains a significant burden in sub-Saharan Africa. Infectious keratitis is a leading cause of unilateral blindness, often due to bacteria, fungi, or viruses. Orbital cellulitis is a significant cause of visual morbidity and mortality, especially in children.