The Human Health Impacts of the Red Imported Fire Ant in the Western Pacific Region Context: A Narrative Review.

Background: The red imported fire ant (RIFA) is one of the world's most destructive invasive species. RIFA stings are painful and can lead to allergic reactions, including life-threatening anaphylaxis, yet health impacts remain inadequately defined. Methods: We searched MEDLINE (Ovid) and Google Scholar (grey literature) from inception until 20 September 2023 for articles in English using search terms related to red imported fire ants and allergies, including anaphylaxis. Results: Approximately a third of the population in RIFA-infested areas are stung each year. The most frequent reaction is a sterile 1-2 mm pseudo pustule on the skin. Approximately 20% of stings cause a large local reaction and between about 0.5% and 2% stings cause a systemic allergic reaction which can range from skin symptoms to life-threatening anaphylaxis. Local biodiversity is also significantly disrupted by invading RIFA and may lead to complex adverse effects on human health, from agriculture losses to expanded ranges for pathogen vectors. Conclusions: The potential for red imported fire ants to establish themselves as an invasive species in the Western Pacific presents a substantial and costly health issue. Successful eradication and surveillance programs, to identify and eradicate new incursions, would avoid substantial health impacts and costs.