Useful Links

Advisory for Swine Flu (Swine Influenza)

Feb 18, 2015

Category: Guidelines

Message on H1N1 (Swine Flu)

DELHI – 110007


Swine influenza is caused by influenza A subtypes H1N1 (most common), H1N2, H2N3, H3N1, H3N2, H7N9 that infect the respiratory tract. The virus infecting people this year is the one that infected the people last year. Gene sequencing of the H1N1 virus by premier labs has demonstrated that the virus has not mutated.

Incubation Period from exposure to first symptom is 1-4 days with average of 2 days. It is most contagious during the first 5 days of illness.

Symptoms :-

  • Fever
  • Cough
  • Sore throat
  • Runny or stuffy nose
  • Bodyaches
  • Headache
  • Chills
  • Fatigue
  • Diarrhoea
  • Nausea
  • Vomiting
  • Fever 100O F or greater for more than 3 days
  • Rash
  • Chest Pain while breathing
  • Breathlessness
  • Pneumonia

These symptoms develop 1-3 days after exposure to any strain of the influenza family of viruses that is endemic in pigs and continue for 7-14 days.

Transmission :-

Swine flu is transmitted from person to person by inhalation or ingestion of droplets containing virus from people coughing or sneezing and not by eating cooked pork.

When to see a doctor :-

It is not necessary to see a doctor if one is healthy and develop mild flu symptoms and signs. Visit the doctor if one is having chronic disease like chronic obstructive pulmonary disease (COPD) or heart disease or pregnancy and develop moderate or severe flu symptoms.

Risk Factors :-

Swine farmers and Veterinarians have higher risk of swine flu. Smoking, not wearing gloves while working with sick animals increases the likely hood of hand to eye, hand to nose or hand to mouth transmission of virus.

If one has travelled to area where many people are affected by H1N1 virus, one may be exposed to the swine flu virus.

Complications :-

  • Worsening of chronic condition like asthma, diabetes mellitus, heart disease,
  • Pneumonia
  • Confusion, Seizures
  • Respiratory Failure

Diagnosis :-

Diagnosis of confirmed swine flu require laboratory test of respiratory sample e.g. nasal swab, throat swab for particular antigens (surface proteins) in specialized laboratories. Doctors collect and send nasal swab/throat swab to the specialized laboratory for confirmation of swine flu virus.

Treatment :-

Anti viral drugs make the illness milder and prevent serious complications. 

Tablet Oseltamivir (Tamiflu/Fluvir) or Zanamivir (Relenza) within 48 hours after the onset of symptoms or after 48 hours in high risk patients. They should not be used indiscriminately because of the risk of viral resistance. They are also not recommended if the flu symptoms have been present for more than 48 hours. Pregnant females can be treated with the anti-viral drugs.

Majority of the people infected with the virus make a full recovery without anti-viral drugs.

Prevention :-

  • Avoid exposure to the virus by not touching eyes, nose or mouth with infected hands.
  • Avoid close proximity to persons with flu like symptoms.
  • Use standard infection control including washing hands with soap and water or with alcohol based hand sanitizers.
  • Disinfect household services with diluted chlorine bleach solution.
  • People who suffer from sneezing or cough should use surgical mask as they prevent 50% of airborne exposures but offer no protection against surface droplets.
  • Watchful waiting.
  • Stay at home.
  • Avoid crowds, parties and people who are coughing and sneezing.
  • If one cannot avoid crowds or parties, try to remain aware of people and be away by 6 feet from anyone coughing or sneezing.
  • Vitamins, plenty of rest do not prevent H1N1 infections but may reduce the effects of infection by strengthening the immune system.
  • Saline nasal washes, gargling with saline may reduce viral virus from mucus membranes.
  • Vaccination of the workers against influenza who work in poultry and swine, veterinarians.
  • Standard commercial swine flu vaccines are effective in controlling the infections. Single dose of vaccine creates enough antibodies to protect against the virus within 10 days.
  • Present vaccination strategies for swine influenza virus control and prevention in swine farms include the use of one of the several bivalent or trivalent flu vaccines containing H1N1 antigens commercially available. 
  • Vaccination of all children from 6 months to 4 years of age, people more than 50 years of age, asthmatics, cardio-vascular, renal, hepatic, neurological, hematological disorders, diabetes mellitus, HIV, pregnancy, morbidly obese (BMI ≥ 40), health care professionals.

Side effects of Vaccines :-

Flu shot vaccine (made from killed virus particals): - Soreness, redness, swelling at the injection site, muscle aches, nausea, low grade fever.

Nasal spray vaccine (made from live virus) : runny nose, wheezing, cough, vomiting, low grade fever.

Intradermal shot (trivalent vaccine)  : redness, swelling.

The people who are allergic to eggs should not get vaccine unless tested and advised by the doctor.

Precautions while air travelling :-

  • If a person sitting next to you or within 6 feet is coughing/sneezing, request the flight attendant to offer the person a mask.
  • If seats are available 6 feet or more away from the coughing/sneezing person, change your seat because the air is recirculated though HEPA filters.
  • Turn away from the coughing/sneezing person and turn the air vent towards the person to blow the droplets away.

Chief Medical Officer

Previous page: Flower Show Next page: Flower Show-2018