Stíflu

Stíflu is the Icelandic term for seasonal influenza, an infectious respiratory illness caused by influenza A and B viruses. It occurs in annual epidemics and can lead to significant illness and strain on health systems. Influenza C causes milder disease and is less common in humans. The term stíflu is commonly used in everyday Icelandic language.

Transmission occurs mainly through respiratory droplets when an infected person coughs or sneezes, but can also spread via contaminated surfaces. People are most contagious in the first 1–2 days after symptoms begin, though they can transmit the virus for several days.

Clinical features typically begin suddenly and include fever, chills, muscle or body aches, headache, fatigue, cough, sore throat, and sometimes nasal congestion. Many experience weakness and loss of appetite. Complications can include pneumonia, bronchitis, or worsening of chronic conditions such as asthma or heart disease, especially in young children, older adults, pregnant people, and those with weakened immune systems.

Diagnosis is usually clinical, based on symptoms and signs. Laboratory testing, such as RT-PCR or rapid influenza diagnostic tests, may be used in hospital settings or during outbreaks to confirm the infection or guide treatment, particularly for high-risk patients.

Treatment is mostly supportive, with rest, fluids, and fever/pain relief as needed. Antiviral medications (for example oseltamivir or zanamivir) may shorten illness and reduce complications when started early, especially in high-risk individuals or those with severe illness.

Prevention centers on annual vaccination, which is the primary preventive measure. Other measures include good hand hygiene, respiratory etiquette, staying home when ill, and, in certain settings or outbreaks, targeted antiviral prophylaxis. Seasonal vaccination and surveillance help reduce the impact of stíflu in Iceland.