Swine flu is a human respiratory infection caused by the influenza-causing H1N1 strain that started in pigs. It’s highly contagious and spreads through the air and droplets. Touching surfaces that have been contaminated with secretions of a patient can lead to infection. In 2009, the World Health Organisation (WHO) declared it a pandemic when it started infecting humans.
H1N1 is a seasonal disease and WHO has said that the swine flu virus is not affected by any variation in temperature. The symptoms of swine flu are quite similar to the common flu and several symptoms of H1N1 overlap with COVID-19 as well. Symptoms develop about one to three days after exposure to the virus and it is not taken seriously in the initial stages until critical symptoms set in. Some common symptoms of the H1N1 flu are fever, cough, sore throat, chills, runny or stuffy nose, watery and red eyes, body ache, fatigue, and headache. Some distinguishing symptoms of COVID-19 that are rare in swine flu include loss of smell and taste, breathlessness, and rashes on the body.
Since the COVID-19 pandemic is ongoing, a precise differential diagnosis is the only way to confirm the infection due to common symptoms. Sneezing is common in swine flu but is less common in COVID-19 currently. Respiratory collapse and death occur in severe situations associated with the swine flu. Onlymyhealth editorial team spoke to Dr. Chandrasekhar Nair - Director & Chief Technical Officer (CEO), Molbio Diagnostics, to know about the importance of identification and control of H1N1 flu and tips to prevent it.
Why is proper identification and control of H1N1 flu essential?
H1N1 swine flu was the last major pandemic that inflicted havoc in many parts of the world before the COVID-19 pandemic engulfed the world. Recently, there has been a spike in swine flu cases in India and medical experts have found that patients with H1N1 are getting misdiagnosed with COVID-19 due to overlapping symptoms, which can lead to improper treatment and further spread of the disease. Hence, it is vital to understand swine flu and differentiate it from COVID-19.
How to diagnose Swine flu?
Accurate and timely diagnosis with early detection of the causative agent enables proper medical management leading to:
 precise rather than presumptive treatment, and
 incorporation of adequate measures rapidly to interrupt transmission.
Rapid influenza antigen diagnostic tests (RIDTs) and direct and indirect immunofluorescence tests for influenza A are widely available but have variable sensitivity (10-70%) and are non-specific for detecting H1N1 influenza in clinical specimens. As a negative viral culture does not exclude infection, viral isolation and nucleic acid amplification tests, such as real-time PCR, are considered the most reliable diagnostic tests for H1N1. Current viral culture or Real-Time PCR tests have limitations of skilled manpower, elaborate infrastructure, and delayed turnaround time.
Innovative testing solutions like Truenat have ensured rapid precise testing away from centralised labs to universal access and facilitated early + accurate diagnosis of H1N1 to propel therapy initiation within a few hours of presentation. Such faster, precise diagnosis not only accelerates better patient outcomes, but also catalyses control and limits spread and also enables differential detection of COVID-19, in needy cases with the same instrument.
Prevention tips for H1N1 flu
Immunocompromised individuals must avoid crowded spaces, closed, poorly ventilated areas and mask up, especially in confined spaces. Frequent hand-washing and isolating when sick are useful approaches to the protection of self and close contact. Oseltamivir therapy should be recommended, especially for high-risk individuals, as it can potentially reduce the duration of illness and transmissibility when started early.