Abstract
Purpose: :
Epidemic keratoconjunctivitis is an acute illness mostly produced by adenoviruses (Ad). Keratoconjunctivitis can initiate as an acute follicular conjunctivitis that usually affects both eyes, successively appearing several injuries in more than half of the cases, and it is characterized by a diffuse point-like epithelial keratitis that evolves either to a healing condition or towards subepithelial injuries that can last for varying periods of time even persisting during months, which can produce visual alterations, affecting the quality of life of the patient. Ad8, Ad19, and Ad37 are the most frequent types responsible for the milder forms, but epidemic events and more serious disease are related to Ad8 type. The present work documents an outbreak of epidemic keratoconjunctivitis among ophthalmology residents, its influence in the presentation of the communitarian cases and the implementation of successful control measures for its containment.
Methods: :
Isolation of the etiologic agent was achieved in cultured VERO cells. Through molecular tests, such as PCR and DNA sequencing, the genotype of the isolated virus was identified. The sequences obtained were aligned with data reported in the NCBI GenBank. A scheme of outbreak control measures was designed to enforce correct sanitary measures. The statistical program Epi info 2002 and openepi were used to determine the attack rate. The Excel Microsoft® program was used to elaborate the endemic channel.
Results: :
Nine of the ten samples studied were isolated from the culture and identified by PCR Ad-specific. Sequencing analysis allowed the identification of Ad8 as responsible for the outbreak. The attack rate was of 24.39 cases per 100. The epidemic curve allowed to identify a disseminated source in the institute. It was not possible to calculate the incubation periods among the cases. The endemic channel showed the presence of an epidemic keratoconjunctivitis among the patients that had been cared for at the out-patient services.
Conclusions: :
An outbreak within our institute caused by Ad8 from a disseminated source it was characterized by molecular and epidemiological studies. Because the transmission of this agent is through direct contact, it is reasonable to think that the transmission mechanism occurred due to relaxation in the hygiene measures during handling of patients. We can assure that the conjunctivitis among the ophthalmologist was not random; it was originated by faulty basic hygiene measures.
Keywords: adenovirus • clinical (human) or epidemiologic studies: health care delivery/economics/manpower • clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology