Dr Paramdeep Bilhu of the London College of Optometrists notes that Live Science highlights conjunctivitis is frequently caused by highly resistant viruses. These pathogens survive standard disinfectants and may not be fully inactivated by alcohol-based products or hydrogen peroxide solutions.
The physician explains that while allergic reactions can trigger conjunctivitis, more than 75 percent of cases arise from adenoviruses. This family of viruses also fuels common cold and flu symptoms. Adenoviruses demonstrate notable resilience, and routine alcohol-based sanitizers or hydrogen peroxide products may not reliably eradicate them. Moreover, an individual infected with an adenovirus can remain contagious for up to two weeks after infection begins.
Viral conjunctivitis spreads through airborne droplets and can travel along the mucous membranes linked to the respiratory system, tear ducts, and the conjunctiva. Transmission occurs when an infected person speaks, sneezes, or coughs, releasing tiny droplets. People with conjunctivitis commonly experience a strong urge to rub their irritated eyes, which can facilitate further spread as the virus transfers from skin to objects, and then to hands and faces of others who have not been exposed.
Bilhu notes that the risk of conjunctivitis is highest among young children, who spend substantial time in close contact and may not consistently follow hygiene practices.
The discussion also references a separate fragility linked to a parasite transmitted from cats, underscoring the importance of distinguishing different eye health risks and their unique transmission pathways.