Influenza H1N1

Author and editor: Alida Fernandes


H1N1, also commonly known as the swine flu, is a subtype of the influenza A virus (Jilani, Jamil & Siddiqui, 2020). The swine flu virus causes complications in the respiratory system and in serious cases may be fatal (Jilani, Jamil & Siddiqui, 2020). As the name suggests, swine flu is commonly found in pigs and can be a risk for swine and humans (Jilani, Jamil & Siddiqui, 2020). On June 11th, 2009 the severity of swine flu caused the declaration of an H1N1 pandemic by the World Health Organization due to the high volume of infected individuals in over 30 countries (Jilani, Jamil & Siddiqui, 2020).



The H1N1 virus is an extremely contagious infection that attacks the respiratory system of pigs and is caused by one of many subtypes of influenza A (Dandagi & Byahatti, 2011). Through aerosols, direct and indirect contact with an infected individual, and asymptomatic infected pigs, the virus is quickly spread (Dandagi & Byahatti, 2011). The swine flu is either spread between pigs and humans or between one infected human to another healthy individual (Dandagi & Byahatti, 2011).



Symptoms of H1N1 may include:

  • Fever and Chills 
  • Cough
  • Sore throat
  • Congested eyes
  • Shortness of breath
  • Headache
  • Abdominal pain or Diarrhea 
  • Vomiting
  • Decreased appetite 
  • Fatigue (Jilani, Jamil & Siddiqui, 2020) (Dotis & Roilides, 2009)


Risk Factors 

Risk factors of contracting H1N1 may include:

  • Young children under the age of 5
  • Elderly adults over the age of 65 
  • Pregnant women (Jilani, Jamil & Siddiqui, 2020)
  • Individuals with lung disorders including COPD, Bronchial asthma or pneumonia 
  • Obesity 
  • Individuals with cancer or autoimmune diseases (Jilani, Jamil & Siddiqui, 2020)



Individuals suffering from flu-like symptoms including fever, cough or sore throat or battling acute pneumonia, especially those residing in a place where a swine flu outbreak is prevalent, should be tested for carrying the swine flu virus (Jilani, Jamil & Siddiqui, 2020; Soleimani & Akbarpour, 2011).

Individuals can get tested for the H1N1 virus using a nasal or throat swab that uses the sample to detect the presence of the virus  (Jilani, Jamil & Siddiqui, 2020).



Pharmaceutical Treatment & Vaccines

In order to refrain from getting the H1N1, it is highly recommended to receive 1 dose of the FDA-approved swine flu vaccine (Jilani, Jamil & Siddiqui, 2020). The vaccine creates immunity from the H1N1 virus to protect individuals from infection (Jilani, Jamil & Siddiqui, 2020). If diagnosed with the H1N1 flu, antiviral drugs such as Oseltamivir and Zanamivir may ease symptoms of the swine flu (Rewar, Mirdha & Rewar, 2016). Medication is most effective when taken 48 hours after initial symptoms are presented (Rewar, Mirdha & Rewar, 2016). 

Caution should be taken in order to maintain safe conditions and prevent the spread of the swine flu in places where the virus is prevalent (Jilani, Jamil & Siddiqui, 2020). Good preventative methods include vaccinating pigs and ensuring those who work closely with swine wear gloves and face masks as well as properly disinfect all areas  (Jilani, Jamil & Siddiqui, 2020). Frequent hand washing and sterilization of work areas should be practiced, especially where the swine flu is known to be active (Jilani, Jamil & Siddiqui, 2020).

Non-Pharmaceutical Treatment – Reduction of Influenza Spread

Non-pharmaceutical methods available to reduce influenza virus infection include community health education about the importance of social distance, and personal hygiene ( Sharma et al.2019). Biosecurity measures, regular disease surveillance and monitoring program, farm management practice including washing hands (Khanna et al. 2012, Itolikar et al. 2015, Singh et al. 2011, Scolaro et al .2017), follow the disinfection and sanitary practices, isolating people with flu from the public places.

Follow biosafety standards: use the face mask, covering nostrils and mouth while sneezing or coughing (Dhama et al. 2012). Follow the infection control practices, create a separate isolation ward, distribution of the information, Education and Communication (IEC) material in hospitals and schools (Mahesh et al. 2014).


Misdiagnosis Articles

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Dandagi, G. L., & Byahatti, S. M. (2011). An insight into the swine-influenza A (H1N1) virus infection in humans. Lung India : official organ of Indian Chest Society, 28(1), 34–38.

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