Viral and chlamydial causes of infectious conjunctivitis
| Causative agent (references) | Differential diagnosis | Epidemiology |
|---|---|---|
| DNA viruses: | ||
| Adenovirus (3) | EKC | Primarily types 8 and 19, but types 2–5, 7, 9, 11, 14, 16, 21–23, and 37 have also been associated with EKC. Highly contagious and transmitted by hand to eye contact, instruments, and solutions. |
| PCF | Primarily types 3, 4, and 7; occasionally type 5. Contagious; droplet transmission, particularly in families. | |
| NSFC | A number of serotypes have been reported including 1–11, 14–17, 19, 20, 22, and 26. | |
| HSV (4, 5) | Conjunctivitis; keratitis or KC | HSV-1 or HSV-2; conjunctivitis is most common in adults and children 1–5 years of age; recurrent disease is common; leading infectious cause of blindness in developed countries. |
| RNA viruses (3): | ||
| Picornavirus | AHC | EV70; CA24; common (epidemic or endemic forms) in developing countries; highly contagious. |
| Measles virus (6) | MVO | Common cause of childhood blindness in developing countries. HSK may complicate measles in developing countries. |
| Chlamydia: | ||
| C trachomatis (7) | NCO | The most common form of infectious ophthalmia neonatorum today; occurs in babies born to mothers with genital infection serovars D–K. |
| ACO | Oculogenital infection caused by serovars D–K, sometimes by B, and rarely by C; common in developed countries and urban areas of developing countries. | |
| Trachoma | Most common cause of preventable blindness in the world and common in rural areas of developing countries particularly in Africa, the Middle East, and Asia; caused by serovars A–C. | |
| LGV conjunctivitis | Very rare and is caused by serotypes L-1, L-2, and L3; transmission either venereally or accidentally in the laboratory. |
EKC=epidemic keratoconjunctivitis; PCF=pharyngoconjunctival fever; NSFC=non-specific follicular conjunctivitis; KC=keratoconjunctivitis; AHC=acute haemorrhagic conjunctivitis; MVO= measles virus ophthalmia; NCO=neonatal chlamydial ophthalmia; ACO=adult chlamydial ophthalmia; LGV=lymphogranuloma venereum; HSK=herpes simplex keratitis; HSV=herpes simplex virus; EV=enterovirus; CA=Coxsackie virus type A.