Swine Flu

Dr Amirthavarshini MBBS

5 Nov, 2022

Swine Flu

H1N1 flu is caused by the H1N1 strain of influenza virus. Family: Orthomyxovirus. Major outbreaks of H1N1 strains in human include the Spanish Flu (1977) and the 2009 swine flu pandemic. The virus contains the glycoproteins- Hemagglutinin and neuraminidase. For this reason they’re described as H1N1, H2N2 etc.

SYMPTOMS:

  • Fever
  • Chills and cough
  • Sore throat
  • Runny nose
  • Watery red eyes
  • Body ache
  • Headache
  • Diarrhoea
  • Nausea and Vomiting

EMERGENCY SYMPTOMS: If they are present consult the General Physician as soon as possible.

  • Difficulty in breathing
  • Chest pain
  • Giddiness
  • Seizures

TRANSMISSION: Airborne spread (oropharynx, nasopharynx). Influenza virus infects the cells that line your nose, throat, and lungs

COMPLICATIONS:

  • Pneumonia
  • Respiratory Failure
  • Confusion
  • Seizures    

DIAGNOSIS:

MOLECULAR TESTS: These may include conventional reverse transcriptase PCR, office based rapid molecular testing, and multiplex molecular platforms that can detect influenza in addition to several other common respiratory pathogens. RT-PCR yields the best performance based on sensitivity and specificity data.

RAPID ANTIGEN OR ANTIBODY IMMUNOASSAYS: Although these are available, most choose molecular testing over these immunoassays owing to their low sensitivity.

VIRAL CULTURE: Although viral culture is available, it is not very useful in clinical practice.

Serology: Serologic testing is not recommended for diagnosis because paired sera ( acute and convalescent) are required, thereby limiting the timelines of these tests in patient care. They may be more useful in epidemiologic studies.

PREVENTION:

  • Wash your hands thoroughly and frequently. Soap and water is beneficial. If not available use alcohol based sanitizers.
  • Cover your coughs and sneeze with a tissue or your elbow or hands, then wash your hands immediately
  • Avoid touching your face,eyes,nose
  • Clean the surfaces which are regularly being touched eg. Door handle.

TREATMENT:

SUPPORTIVE CARE:

  • Drink more fluids and stay hydrated.
  • NSAID’S for pain relief
  • Antivirals which include Oseltamivir, Zanamivir, Peramivir

VACCINE:

The 2009 influenza A (H1N1) monovalent vaccine was released in mid-October. The immunization series consisted of 2 doses for children younger than 10 years consisting of an initial dose and a booster to be administered several weeks later. Adults and children 10 years and older received a single dose. Targeted populations recommended to receive the 2009 H1N1 vaccine included pregnant women, household contacts and caregivers of children younger than 6 months, healthcare and emergency medical personnel, children aged 6 months to 18 years, young adults aged 19-24 years, and persons aged 25-64 years with conditions associated with higher risk of medical complications

ROUTE OF ADMINISTRATION: 0.5ml intramuscularly in the deltoid muscle of upper arm.