Rabinder Shekher
Swine influenza, also called pig influenza, swine flu, hog flu and pig flu, is an infection caused by any one of several types of swine influenza viruses. Swine influenza virus (SIV) or swine-origin influenza virus (S-OIV) is any strain of the influenza family of viruses that is endemic in pigs. As of 2009, the known SIV strains include influenza C and the subtypes of influenza A known as H1N1, H1N2, H2N1, H3N1, H3N2, and H2N3. Swine influenza virus is common throughout pig populations worldwide. Transmission of the virus from pigs to humans is not common and does not always lead to human flu, often resulting only in the production of antibodies in the blood. If transmission does cause human flu, it is called zoonotic swine flu. People with regular exposure to pigs are at increased risk of swine flu infection.
Swine Flu in India
In 2015 the instances of Swine Flu substantially increased to five year highs with over 10000 cases reported and 660 deaths in India. The states reporting the highest number of cases and deaths are Rajasthan, Gujarat, Madhya Pradesh, Maharashtra, Delhi, and Telengana. The circulating strain of influenza being the same, unmutant strain that caused global pandemic in 2009 (A H1N1 pdm 09), the sudden spurt of the cases in the beginning of 2015 left the Indian government unexplained but concerned. Government instructed the affected states to investigate into the epidemiological reasons of such spurt in the states, and had detailed the advisory guidelines to all states. The guidelines are mainly for (a) description of A H1N1 for prompt identification, detection, and distinction from the symptoms of other similar infection such as common flu(cold) (b) categorization of screening of influenza A H1N1 cases, (c) clinical management protocol of Pandemic influenza A H1N1, (d) providing home care, (e) collection of human sample. Besides, through the National Centre for Diseases Control, Directorate General of Health Services , Government of India had placed a tender to procure 8 kits of Assay sets, 37 kits of one step RT-PCR kit, and 36 kits of viral RNA extraction kits.
Transmission to humans
People who work with poultry and swine, especially those with intense exposures, are at increased risk of zoonotic infection with influenza virus. Vaccination of these workers against influenza and surveillance for new influenza strains among this population may therefore be an important public health measure. Other professions at particular risk of infection are veterinarians and meat processing workers, although the risk of infection for both of these groups is lower than that of farm workers.
Signs and symptoms
Direct transmission of a swine flu virus from pigs to humans is occasionally possible . In all, 50 cases are known to have occurred since the first report in medical literature in 1958, which have resulted in a total of six deaths.
According to the Centers for Disease Control and Prevention , in humans the symptoms of the 2009 “swine flu” H1N1 virus are similar to those of influenza and of influenza-like illness in general. Symptoms include fever, cough, sore throat, body aches, headache, chills and fatigue. The 2009 outbreak has shown an increased percentage of patients reporting diarrhea and vomiting. The 2009 H1N1 virus is not zoonotic swine flu, as it is not transmitted from pigs to humans, but from person to person.
The most common cause of death is respiratory failure. Other causes of death are pneumonia (leading to sepsis), high fever (leading to neurological problems), dehydration, electrolyte imbalance and kidney failure.[ Fatalities are more likely in young children and the elderly.
Diagnosis
The CDC recommends real time PCR as the method of choice for diagnosing H1N1. The oral or nasal fluid collection and RNA virus preserving filter paper card is commercially available. This method allows a specific diagnosis of novel influenza (H1N1) as opposed to seasonal influenza. Near-patient point-of-care tests are in development.
Prevention
Influenza spreads between humans when infected people cough or sneeze, then other people breathe in the virus or touch something with the virus on it and then touch their own face. “Avoid touching your eyes, nose or mouth. Germs spread this way.” Swine flu cannot be spread by pork products, since the virus is not transmitted through food. The swine flu in humans is most contagious during the first five days of the illness, although some people, most commonly children, can remain contagious for up to ten days. Diagnosis can be made by sending a specimen, collected during the first five days, for analysis.
Recommendations to prevent spread of the virus among humans include using standard infection control, which includes frequent washing of hands with soap and water or with alcohol-based hand sanitizers, especially after being out in public. Chance of transmission is also reduced by disinfecting household surfaces, which can be done effectively with a diluted chlorine bleach solution.
Experts agree hand-washing can help prevent viral infections, including ordinary and the swine flu infections. Also, avoiding touching one’s eyes, nose or mouth with one’s hands helps to prevent the flu. Influenza can spread in coughs or sneezes, but an increasing body of evidence shows small droplets containing the virus can linger on tabletops, telephones and other surfaces and be transferred via the fingers to the eyes, nose or mouth. Alcohol-based gel or foam hand sanitizers work well to destroy viruses and bacteria. Anyone with flu-like symptoms, such as a sudden fever, cough or muscle aches, should stay away from work or public transportation, and should contact a doctor for advice.
Social distancing, another tactic, is staying away from other people who might be infected, and can include avoiding large gatherings, spreading out a little at work, or perhaps staying home and lying low if an infection is spreading in a community. Public health and other responsible authorities have action plans which may request or require social distancing actions, depending on the severity of the outbreak.
Vaccination
Vaccines are available for different kinds of swine flu. The U.S. Food and Drug Administration (FDA) approved the new swine flu vaccine for use in the United States on September 15, 2009. Studies by the National Institutes of Health show a single dose creates enough antibodies to protect against the virus within about 10 days.
Treatment
If a person becomes sick with swine flu, antiviral drugs can make the illness milder and make the patient feel better faster. They may also prevent serious flu complications. For treatment, antiviral drugs work best if started soon after getting sick (within two days of symptoms). Beside antivirals, supportive care at home or in a hospital focuses on controlling fevers, relieving pain and maintaining fluid balance, as well as identifying and treating any secondary infections or other medical problems. The W.H.O recommends the use of oseltamivir (Tamiflu) or zanamivir (Relenza) for the treatment and/or prevention of infection with swine influenza viruses; however, the majority of people infected with the virus make a full recovery without requiring medical attention or antiviral drugs.
Follow our WhatsApp channel