Can vaccines save sight?

Vaccines may have a role to play against corneal and external ocular disease, because of their success in preventing systemic diseases, according to a presentation given during Cornea Day at the annual meeting of the American Society of Cataract and Refractive Surgery earlier this year.

Minas T. Coroneo, MD, chairman of the Department of Ophthalmology at the University of New South Wales, Sydney, Australia, discussed the vaccines for herpes zoster virus (HZV, which causes shingles and chicken pox) and human papilloma virus (HPV) infections.

The chance of getting an HZV infection during an individual's lifetime is 10–25%, and the associated complications, such as loss of sight, are substantial. The incidence of infection increases with age, and the length of time of the attacks is greater in older patients.“HZV and HPV are highly prevalent and are associated with high morbidity and cost,” said Dr Coroneo.

The Shingles Prevention Study found that a vaccine reduces the incidence of post-herpetic neuralgia, the impact of which is substantial for elderly patients. Ophthalmologists, said Dr Coroneo, should be interested in preventing post-herpetic neuralgia as cranial dermatomes are the second most commonly affected site (following thoracic infections) and because of the potential for loss of sight.

A strategy to prevent shingles is important because available treatments do not prevent post-herpetic neuralgia, which, when left untreated, is associated with further complications. In clinical trials, vaccines have successfully reduced the incidence of HZV infection and post-herpetic neuralgia for up to five years after vaccination.“Vaccines work by inducing specific memory T-cells that normally decrease in number with aging,” Dr Coroneo concluded.