There has been an increasing number of H1N1 viral influenza cases along with infections like dengue in the past few weeks in Bangalore.
The Karnataka health department has put the state on a high alert in view of the same. H1N1 influenza virus had already caused a pandemic in the year 2009. The sudden heavy rains, global climate changes with the recent floods in Kerala are probable reasons for the increase in the number of cases now.
The 2009 pandemic: The swine flu H1N1 virus is responsible for causing respiratory infection in pigs for years but was not recognized as a cause of infection in people prior to the year 2009. The origin was from animal viruses completely unrelated to human H1N1 viruses that have circulated for several years in the general population. The influenza A H1N1 virus that emerged in 2009 was a virus with swine, human and avian genes.
The current Flu season: The government has reported that Influenza A (H3N2) viruses have dominated during 2017-2018 season. However, towards the second half of the year 2018, Influenza B viruses are being more commonly reported.
Symptoms of seasonal influenza including viral H1N1 influenza include:
1. High grade fever and headache
2. Runny nose, burning sensation in eyes
3. Body aches, Muscle aches
4. Throat pain
5. Vomiting and diarrhea
The infection can be self-limiting. However, children, elderly population, those with underlying lung conditions like COPD, Bronchial asthma, post-organ transplant individuals are more susceptible to complications from the influenza.
The diagnosis is based on symptoms and the health care provider may send tests like throat and nasal swabs for further tests. The doctor may start medications pending the availability of tests.
1. Supportive care: Plenty of warm liquids, fruits and vegetables and rest
2. Control of symptoms of fever with paracetamol
3. Avoidance of antibiotics unless there is a secondary bacterial pneumonia
4. Avoidance of pain killers
5. Medications like antivirals may be prescribed by the health care provider
Avoiding panic is the key. If one has symptoms of “Flu”, it is recommended that they stay off work or school to avoid transmission of the virus. Avoid travel if there are symptoms. Air-borne spread and contact are two major ways that spread infection. So, maintenance of strict hand hygiene and appropriate cough etiquette will control the spread of virus in the community. Use of masks, strict hand hygiene and appropriate separation of patients in hospitals are being done to avoid cross infections.
Vaccine: There is a quadrivalent influenza vaccine that offers protection against two strains of influenza A and 2 strains of influenza B types. The vaccine is especially important for children, adults older than 65 years, patients with health conditions like diabetes mellitus, COPD lung, Bronchial asthma and pregnant women. Flu vaccination for pregnant women protects both the mother and the unborn child. Health care providers and nursing staff are also recommended to take the vaccine.
(Dr Swathi Rajgopal is Consultant, Infectious Disease, at Aster CMI Hospital)