Environmental Risk Factors in the Outbreak of Avian Influenza Infection (H5N1): A Case Study in Qom, Iran

Based on reported evidence of an outbreak incidence of highly pathogenic avian influenza (HPAI) in Qom province, this study aimed to evaluate the environmental risk factors in the outbreak of avian influenza infection in this province to provide essential data for developing effective interventions in infection control.

The cross-sectional method was predicted and implemented in two specific phases. In the primary phase of the study, the necessary criteria were extracted using a questionnaire. In another part of the study, the characteristics and spread of the infection in Qom province were evaluated by DotMapper software.

From a total of 175 investigated farms, 95 farm units (54%) were infected and were positive for AI. The results showed that at least one of the environmental risk factors was not controlled in 86% of laying poultry farms and 66% of broiler poultry farms, according to the questionnaire. The findings of statistical analyses for the evaluation of environmental risk factors affecting AI infection in poultry farm units indicate that sanitary land disposal of infected poultry carcasses, waste and manure of birds (odds ratio [OR] = 1.02), complete quarantine and installation of warning signs in contaminated areas (OR = 0.55), the existence of facilities and performance decontamination, as well as the use of effective disinfectants for the disinfection of ventilators, disinfection of poultry vehicles, and equipment and manure of birds (OR = 0.33) have a considerable association with AI infection on poultry farms in Qom province.

Our findings revealed that control and monitoring of environmental risk factors as part of an effective surveillance system for the AI virus are key processes for the propagation and contribute to the spread of the infection.