TITLE:
Seasonal Trends and Risk Factors of Scombroid Fish Poisoning in Muscat, Oman: A Retrospective Observational Study
AUTHORS:
Maryam Al Maamari, Balqees Al Siyabi
KEYWORDS:
Scombroid Fish Poisoning, Histamine Fish Poisoning, Seasonal Trend, Tuna, Food Safety, Oman
JOURNAL NAME:
Open Journal of Epidemiology,
Vol.16 No.1,
February
2,
2026
ABSTRACT: Background: Scombroid fish poisoning (SFP) is a significant but often underreported foodborne illness caused by histamine accumulation in inadequately refrigerated fish, especially species high in free histidine. Study have identified seasonal clustering, particularly in warmer months, attributed to high ambient temperature that promotes bacterial proliferation and histamine formation. Despite growing regional research, data from Oman remain limited. Objective: This study aims to examine the seasonal patterns and risk factors associated with scombroid fish poisoning in Muscat governorate, with focus on fish species, exposure sources, and case severity. Methods: This retrospective observational study was conducted in Muscat governorate, Oman, including 38 cases of suspected fish poisoning reported between 2020-2024. Data obtained from Disease Surveillance and Control Department, included month of occurrence, implicated fish species, source of exposure, severity and outcomes. All cases were analysed using descriptive statistics in Microsoft Excel to evaluate seasonal trends and exposure related risk factors. Results: A total of 38 cases of scombroid fish poisoning were analysed. A strong seasonal clustering was observed during the summer months, with 64.7% of cases occurring in August, 23.5% in October, and 11.8% in May. All cases were associated with the consumption of tuna, especially meals prepared in restaurants. Most case (94.7%) were classified as mild, while 5.3% were moderate. No severe cases or hospitalization were reported, and all patients fully recovered. Common symptoms included rash, flushing, headache, nausea and diarrhoea, consistent with histamine -mediated reactions. Conclusion: The study indicates that scombroid poisoning in Muscat is mostly associated with restaurants served tuna and shows distinct seasonal clustering in August. These findings highlight the need for well-founded food safety regulations, improved cold chain monitoring, and targeted restaurant check-ups to reduce the risk during the summer periods.