svínaflensan

Svínaflensan, or swine influenza, is an infectious disease of pigs caused by influenza A viruses. These viruses normally circulate in pig populations and can occasionally infect humans, usually after direct contact with infected animals. Subtypes such as H1N1 and H3N2 have been found in both pigs and humans.

In humans, infections are typically mild to moderate and resemble seasonal flu: fever, cough, sore throat, runny nose, muscle aches, and fatigue. Some people, particularly children and older adults, may experience vomiting or diarrhea. Human-to-human transmission occurs mainly through respiratory droplets; risk is highest for people who work with pigs.

Diagnosis is by laboratory testing, most often RT-PCR on nasal or throat swabs. Rapid tests exist but may be less reliable. Treatment focuses on supportive care; antivirals such as oseltamivir or zanamivir can reduce symptoms and should be started early in at-risk individuals.

Prevention relies on vaccination and hygiene measures. Seasonal influenza vaccines typically cover H1N1 lineages; vaccination is recommended for high-risk groups and healthcare workers. In agricultural settings, biosecurity and proper hygiene reduce exposure to pigs.

Historically, a major event was the 2009 pandemic when a novel swine-origin H1N1 virus spread globally. After the pandemic, this lineage became part of seasonal influenza A circulation and continues to be monitored by public health and veterinary authorities.