The document summarizes key information about swine flu, including its history, symptoms, diagnosis, treatment, vaccines, and prevention. It notes that swine flu was first identified in 1918 and reemerged in 2009. Symptoms are similar to seasonal flu and include fever, cough, and body aches. Diagnosis involves virus detection from nasal/throat swabs. Treatment focuses on relieving symptoms, though antivirals may be used. Vaccines were developed to protect against the H1N1 strain of swine flu. Prevention emphasizes vaccination, hand washing, and staying home when sick.
2. History about the “Swine Flu”:-
• Swine influenza is not a new disease. It was first diagnosed in the year 1918. It was not clear
then that whether human contracted the virus from pigs or pigs contracted it from humans.
Somewhere between 20-40 million people died from “Spanish Flu” or “La Grippe” which
were the two names for it. To this day it is still unclear whether the strain was swine influenza
or not.
• In the year 1976 on Feb’06′ ,4 comrades were hospitalized and their fellow army recruit died.
The cause of his death came out to be a new strain of influenza with was a variant of H1N1
and was known as A/New Jersey/1976 as told by the health officials 2 weeks later. In
between a new strain was discovered which was A/Victoria/75 (H3N2). President Gerald Ford
made every person gets vaccinated against the disease to prevent people from another
epidemic.This all came to a a halt by Gullain-Barre Syndrome which was a side effect result
from a modern influenza vaccine. Initially 25 people had died of the vaccine, which lead to
the death of more people and which over a period of time spread over to a large population
base.
• Again later in the year 1998, this virus was found in pigs across four US States and within a
year it had spread through pig populations across the US.
• Now, the current outbreak of the virus is in year 2009. This outbreak is due to a new strain of
subtype H1N1 which was not previously reported in pigs. It appears as if this outbreak was
transmitted from humans to pigs and then back to us as the same as the 1918 pandemic.
3. Pathogencity:-
• When influenza virus is introduced into the respiratory tract, by
aerosol or by contact with saliva or other respiratory secretions
from an infected individual, it attaches to and replicates in epithelial
cells. The virus replicates in cells of both the upper and lower
respiratory tract. Viral replication combined with the immune
response to infection (which we’ll discuss in later posts) lead to
destruction and loss of cells lining the respiratory tract. As infection
subsides, the epithelium is regenerated, a process that can take up
to a month. Cough and weakness may persist for up to 2 weeks
after infection.
• A recent paper compiled data from a number of studies in which
human volunteers were given influenza virus, and the production of
virus and flu-like symptoms were recorded.
4. Diagnosis:-
• Swine flu is diagnosed by the history of the patient more so if he lives in an area
that is affected by this strain of virus. The symptoms of flu adds to the suspicion.
As a part of diagnosis it is also important to consider if he has travelled to a high
risk area or has been in contact with an infected person.
Confirmation requires using a ‘Swine Influenza Test Kit’ to analyze samples from
nasal, nasopharyngeal or throat swabs.
• Sometimes more than one type of sample may be used. Although the Kit is not
FDA approved it is believed to be a good test to detect the H1NI virus. The FDA
however directs that the kit can be used in case of an emergency.
• There is a miniscule chance that this kit can produce a false positive result but
overall it is quite reliable.
• A correct diagnosis is important to keep the spread of the disease under check.
5. Nomenclature:-
• The initial outbreak of a novelswine-origin H1N1 flu pandemic strain in 2009 was
called by many names. In July 2009, WHO experts named it "pandemic H1N1/09
virus" to distinguish it from both various seasonal H1N1 virus strains and the 1918
flu pandemic H1N1 strain.
• Some authorities object to calling the flu outbreak "swine flu". U.S. Agriculture
Secretary Tom Vilsack expressed concerns that this would lead to the
misconception that pork is unsafe for consumption. The CDC began referring to it
as "Novel influenza A (H1N1)"; "A/H1N1" is sometimes used. The CDC stopped
using the nomenclature "novel H1N1" and updated various web pages to reflect
the change to "2009 H1N1 Flu". In the Netherlands it was originally called "pig flu"
but is now called "Mexican flu" by the national health institute and in the media.
South Korea and Israel briefly considered calling it the "Mexican virus".
• Later the South Korean press used "SI", short for "swine influenza". Taiwan
suggested the names "H1N1 flu" or "new flu", which most local media
adopted.The World Organization for Animal Health proposed the name "North
American influenza". The European Commission adopted the term "novel flu
virus".
6. Symptoms:-
• Swine flu symptoms in humans are similar to those of infection with other flu
strains:
• Fever
• Cough
• Sore throat
• Body aches
• Headache
• Chills
• Fatigue
• Diarrhea
• Vomiting
Swine flu symptoms develop about one to three days after you're exposed to the
virus and continue for about eight days, starting one day before you get sick and
continuing until you've recovered.
7. Treatment:-
• Most cases of flu, including H1N1 flu, need no treatment other than
symptom relief. If you have a chronic respiratory disease, your
doctor may prescribe additional medication to decrease
inflammation, open your airways and help clear lung secretions.
• The antiviral drugs oseltamivir (Tamiflu) and zanamivir (Relenza) are
sometimes prescribed to reduce the severity of symptoms, but flu
viruses can develop resistance to them. Some researchers
recommend further study on both of these drugs due to
uncertainty about their effects beyond the initial reduction in
symptoms.
• To make development of resistance less likely and maintain supplies
of these drugs for those who need them most, antivirals are
reserved for people at high risk of complications.
8. Vaccines:-
• Existing vaccines against seasonal flu provide no protection. Vaccines were released in North
America in late October. Production may be 3 billion doses per year rather than the earliThe
2009 flu pandemic vaccines are the set of influenza vaccines that have been developed to
protect against the pandemic H1N1/09 virus. These vaccines either contain inactivated
(killed) influenza virus, or weakened live virus that cannot cause influenza. The killed vaccine
is injected, while the live vaccine is given as a nasal spray. Both these types of vaccine are
usually produced by growing the virus in chicken eggs. Around three billion doses will be
produced annually, with delivery from November 2009.[
• In studies, the vaccine appears both effective and safe,providing a strong protective immune
response and having similar safety profile to the normal seasonal influenza vaccine. However,
about 30% of people already have some immunity to the virus, with the vaccine conferring
greatest benefit on young people, since many older people are already immune through
exposure to similar viruses in the past. The vaccine also provides some cross-protection
against the 1918 flu pandemic strain.
• Early results (pre-25 December 2009) from an observational cohort of 248,000 individuals in
Scotland have shown the vaccine to be effective at preventing H1N1 influenza (95.0%
effectiveness [95% confidence intervals (CI) 76.0–100.0]) and influenza related hospital
admissions (64.7% [95%CI 12.0–85.8]).
9. Incubation
Period:-• In order to best survive the pandemic flu, you'll want to understand
how it infects you and how long you have before you start showing
symptoms, which is referred to as the incubation period. That is,
how long the virus stays in your system without causing symptoms.
The CDC estimates that the incubation period for swine flu is 1-7
days, although probably closer to 1-4 days, with a median of 2 days.
This is consistent with seasonal flu. You should note that people can
be contagious during the incubation period, even up to a day before
systems start to show. In general, the incubation period for the
influenza virus (all types of flu) is 2 days, but can range from 1 to 5
days. In most US cases, the incubation period for swine flu seems to
range from 2 to 7 days.
• Obviously, the exact swine flu incubation period is still disputed. It
would be wise to keep a close eye on symptoms for about a week,
and up to 10 days to be safe.
10. Prevention:-
• The Centers for Disease Control and Prevention now recommend flu vaccination for all Americans
older than 6 months of age. An H1N1 virus is one component of the seasonal flu shot for 2013-
2014. The flu shot also protects against two or three other influenza viruses that are expected to be
the most common during the 2013-2014 flu season.
• The vaccine will be available as an injection or a nasal spray. The nasal spray is approved for use in
healthy people 2 through 49 years of age who are not pregnant.
• These measures also help prevent H1N1 swine flu and limit its spread:
• Stay home if you're sick. If you do have H1N1 swine flu, you can give it to others starting about 24
hours before you develop symptoms and ending about seven days later.
• Wash your hands thoroughly and frequently. Use soap and water, or if they're unavailable, use an
alcohol-based hand sanitizer. Flu viruses can survive for two hours or longer on surfaces, such as
doorknobs and countertops.
• Contain your coughs and sneezes. Cover your mouth and nose when you sneeze or cough. To avoid
contaminating your hands, cough or sneeze into a tissue or the inner crook of your elbow.
• Avoid contact. Stay away from crowds if possible. And if you're at high risk of complications from
the flu — for example, you're younger than 5 or age 65 or older, you're pregnant, or you have a
chronic medical condition such as asthma — consider avoiding swine barns at seasonal fairs and
elsewhere.
• Reduce exposure within your household. If a member of your household has H1N1 swine flu,
designate one other household member to be responsible for the ill person's close personal care.
