Infection Flu Disease from Influenza Virus, and Treatment
Meaning of Influenza Virus: Influenza virus is referred to as influenza virus. It is
divided into A, B and C types. Influenza viruses discovered in
recent years will be classified as D types. Influenza virus can cause
flu, infection and disease of many animals such as human, bird, pig, horse, bat,
etc. It is the pathogen of human and animal diseases such as human flu, bird
flu, swine flu, horse flu and so on.
The clinical symptoms typical of these diseases are acute
high fever, systemic pain, marked fatigue, and respiratory symptoms. Influenza
viruses are mainly transmitted through droplets in the air, contact between
susceptible and infected persons, or contact with contaminated items.
Generally
autumn and winter season is its high incidence. Human influenza is mainly caused
by influenza A virus and influenza B virus. Influenza A viruses often undergo
antigen mutations and can be further divided into subtypes such as H1N1, H3N2,
H5N1, H7N9 (where H and N represent the two surface glycoproteins of the
influenza virus, respectively). The flu virus is not resistant to the outside
world.
Animal influenza viruses usually do not infect humans, and human
influenza viruses do not usually infect animals, except for pigs. Pigs can be
infected with both human and avian influenza viruses, but they are mainly
infected with swine influenza virus. After a few animal influenza viruses adapt
to humans, they can cause a pandemic in humans.
Name: Influenza virus
Boundary: Virology
Branch: Orthomyxoviridae
Genus: Influenza virus
Group: Group V ((-) ssRNA)
Short name: Flu virus
The main symptoms: Headache, fever,
runny nose, muscle pain, weakness
Diameter: Normal 80-120 nm
Method of Transmission: Droplets, direct
contact, contact with contaminated items
Influenza Virus Particulars
Influenza virus is a representative species of
Orthomyxoviridae, referred to as influenza virus, including human influenza
virus and animal influenza virus.
Human influenza virus is divided into A (A),
B (B), C ( C) Type III, the pathogen of influenza (flu). Among them, the
antigenicity of influenza A virus is susceptible to mutation, which has caused
worldwide pandemics.
For example, during the pandemic from 1918 to 1919, at
least 20 million to 40 million people died of influenza in the world.
Influenza
B virus is also relatively pathogenic to humans, but people have not found that
influenza B virus has caused worldwide Pandemic.
Influenza C virus causes only
insignificant or minor upper respiratory tract infections in humans and rarely
causes epidemics. Influenza A virus was successfully isolated in 1933,
influenza B virus was obtained in 1940, and influenza C virus was not
successfully isolated until 1949.
What is the Influenza Virus Classification?
According to the target of influenza virus infection, the
viruses can be divided into human influenza virus, swine influenza virus,
equine influenza virus and avian influenza virus.
Among them, human influenza
virus can be divided into three types according to the antigenicity of their
nuclear proteins:
- Influenza A virus, also known as influenza A virus
- Influenza B virus, also known as influenza B virus
- Influenza C virus, also known as influenza C virus
Influenza
viruses that infect birds, pigs and other animals
have the same nuclear protein antigenicity as human influenza A viruses.
But as influenza A, B and C viruses are classified only for human
influenza
viruses, they are usually not Influenza viruses other than human hosts
such as
avian influenza viruses are referred to as influenza A viruses.
On the basis of nucleoprotein antigenicity, influenza viruses
are also divided into different subtypes based on the antigenicity of
hemagglutinin HA and neuraminidase NA.
What is the Morphology of Influenza Virus?
Influenza viruses are spherical, and newly isolated strains
are mostly filamentous, with a diameter of 80 to 120 nanometers. The length of
the filamentous influenza virus can reach 4000 nanometers.
The structure of influenza virus can be divided into three
parts: envelope, matrix protein and core.
What is the core of Influenza Virus?
The core of the virus contains the genetic material that
stores the virus's information and the enzymes necessary to replicate that
information.
The genetic material of the influenza virus is a single-stranded
negative-stranded RNA, which is abbreviated as ss-RNA. Ss-RNA is combined with
nuclear protein (NP) and entangles into ribonucleosomes.
Flu virus structure pattern
(RNP), exists in extremely dense forms. In addition to
ribonucleosomes, there are RNA polymerases responsible for RNA transcription.
The RNAs of influenza A and B viruses consist of 8 segments,
while influenza C viruses have one less segment than them.
The first, second and
third segments encode RNA polyaggregate and the fourth segment Responsible for
encoding hemagglutinin.
The fifth segment encodes a nucleoprotein, the sixth
segment encodes a neuraminidase.
The seventh segment encodes a matrix protein,
and the eighth segment encodes a To non-structural proteins that splice RNA
functions, other functions of this protein are unknown.
What the influenza C virus lacks is the sixth segment, and
the hemagglutinin encoded by the fourth segment can simultaneously perform the
function of neuraminidase.
Matrix Protein
Negative staining transmission electron microscope × 175000
Negative staining transmission electron microscope × 175000
The matrix proteins form the shell of the virus.
In fact,
there are membrane proteins (M2) in addition to the matrix proteins (M1). M2
protein has ionic (mainly Na +) channels and regulates the pH value in the
membrane, but the amount is small.
The matrix protein tightly binds to the
outer envelope of the virus to protect the core of the virus and maintain the
spatial structure of the virus.
After the influenza virus has completed its reproduction in
the host cell, the matrix protein is distributed on the inner wall of the host
cell's cell membrane.
The formed viral nucleocapsid can recognize the site containing
the matrix protein on the host cell membrane and combine with it to form the
viral structure. The budding form highlights the release of the mature virus.
Envelope
The envelope is a layer of phospholipid bilayer that is
wrapped outside the matrix protein. This membrane is derived from the host's
cell membrane. Mature influenza virus sprouts from the host cell, envelopes the
host's cell membrane and detaches from the cell and de-infects. Next target.
In addition to the phospholipid molecule in the envelope,
there are two very important glycoproteins: hemagglutinin and neuraminidase.
These two types of proteins highlight the virus in vitro and are about 10 to 40
nanometers in length, called spikes.
Generally, there are 500 hemagglutinin
spikes and 100 neuraminidase spikes on the surface of an influenza virus.
The
antigenicity of hemagglutinin and neuraminidase will change in influenza A
virus, which is the basis for distinguishing virus subtypes.
Hemagglutinin (HA)
It is columnar and can bind to receptors on the surface of
red blood cells of animals such as humans, birds, pigs, guinea pigs, etc. to
cause coagulation, so it is called hemagglutinin.
Hemagglutinin is hydrolyzed
into light and heavy chains. The latter can be combined with the sialic acid
receptor on the host cell membrane, while the former can help the virus
envelope and host cell membrane to fuse with each other.
Hemagglutinin plays an
important role in the process of virus introduction into host cells.
Hemagglutinin is immunogenic and anti-hemagglutinin antibodies can neutralize
influenza viruses.
Neuraminidase (NA)
It is a mushroom-shaped tetrameric glycoprotein with sialic
acid hydrolysis activity. When mature influenza virus leaves the host cell
through budding, hemagglutinin on the surface of the virus will maintain
contact with the host cell membrane through the sialic acid receptor.
It is
necessary to hydrolyze sialic acid by neuraminidase to cut off the final
connection between the virus and the host cell, so that the virus can be
smoothly released from the host cell and then infect the next host cell.
Therefore, neuraminidase has also become a target for the treatment of
influenza, and oseltamivir designed for this enzyme is one of the most famous
anti-flu drugs.
What is the Naming Method of Influenza Viruses?
According to the amendment to the influenza virus strain
nomenclature adopted by the World Health Organization in 1980, the naming of
influenza strains includes six elements:
Type / host / isolation area / strain
number / year of isolation (HnNn), which is, omit host information, omit
subtype information for influenza B and C viruses. For example, A / swine /
Lowa / 15/30 (H1N1) indicates that the nucleoprotein is type A.
In 1930, the
pig was used as the host H1N1 subtype influenza virus strain isolated at lowa.
The strain number is 15, It is also the first influenza virus strain isolated
from humans.
What is Influenza Virus Mutation?
Influenza virus mutations include antigenic mutations,
temperature-sensitive mutations, host range and sensitivity to non-specific
inhibitors, but the most important are antigenic mutations.
Different from
other viruses, the antigenic mutation is characterized by the susceptibility of
surface antigens HA and NA to mutation. There are two forms of mutation, namely
antigenic shift and antigenic drift.
The magnitude of the flu virus surface antigen mutation
directly affects the scale of the flu.
If the magnitude of the mutation is
small, it is a quantitative change, which is called antigenic drift. It
produces virus strains that can cause small and medium epidemics.
If the
magnitude of the antigenic mutation is large. It is a qualitative change,
called an antigenic change, and a new subtype is formed.
At this time, the
population generally lacks immunity to it, and often causes a large epidemic,
even a worldwide epidemic.
For example, HA and NA of influenza A virus are
prone to antigenic transformation, most or all of the amino acids constituting
HA and NA can be changed.
The new subtypes with completely different
antigenicity appear. Variation changes from quantitative to qualitative.
When
new influenza virus subtypes appear, the population generally lacks immunity to
them and is therefore prone to pandemics.
Antigenic shift
Antigenic shift has a large mutation range, which is a
qualitative change, that is, one or two of the antigenic structure of the virus
strain has mutated, which is different from the antigen of the previous
epidemic strain, forming a new subtype (such as H1N1 → H2N2, H2N2 → H3N2 ).
Due
to lack of immunity to mutant virus strains, causing pandemic influenza. If two
different viruses infect the same cell at the same time, genetic recombination
can occur to form a new subtype.
The H3N1 subtype was isolated in humans
infected with influenza A virus H1N1 and Hong Kong influenza A virus H3N2 that
were prevalent in the Soviet Union before 1978, indicating that such mutations
can occur during natural epidemics.
It has been thought that the alternation
between old and new subtypes was rapid. Once the new subtype appeared, the old
subtype quickly disappeared.
However, although the H1N1 reappeared in 1997, it
has not yet replaced the H3N2, but both have become popular. Until 1998, the
antigen of the representative strain of type A3 (H3N2) mutated, and the Wuhan
strain was replaced by the Sydney strain.
People did not have immunity to the
new strain, which caused a new epidemic.
Antigen drift
Antigenic drift has a small or continuous
variation, which belongs to quantitative variation, that is, intra-subtype
variation.
It is generally believed that such mutations are caused by point
mutations in viral genes and population immune selection, and the epidemic
caused is small-scale.
Among the three influenza viruses that infect humans,
influenza A virus has strong variability, followed by type B, and the
antigenicity of influenza C virus is very stable.
Variation of influenza B virus will generate new mainstream
strains, but there is cross-immunity between the new strain and the old strain,
that is, the immune response against the old strain is still effective against
the new strain.
Influenza A virus is the most frequently mutated type. Every
ten years, a large antigenic mutation occurs, resulting in a new strain. This
change is called antigenic transformation or qualitative change of antigen.
In
influenza A Small mutations of the antigen can also occur within the subtype,
and its manifestation is mainly a point mutation of the amino acid sequence of
the antigen, which is called antigen drift and also the quantity change of the
antigen.
The antigenic change may be a change in the hemagglutinin antigen and
the neuraminidase antigen at the same time, which is called a large family
variation.
It may also be only a hemagglutinin antigen mutation, and the
neuraminidase antigen does not change or has only a small mutation, which is
called Subtype variation.
There is no uniform understanding of the variability of
influenza A virus in the academic community.
Some scholars believe that it is
because the influenza A virus transmitted in the population is facing greater
immune pressure, which promotes the mutation of the viral nucleic acid.
Other
scholars believe that the mutation of the virus is caused by genetic
recombination of human influenza A virus and avian influenza virus
simultaneously infected pigs.
The opinion of the latter group of scholars is
supported by some facts. Laboratory work has shown that three of the eight
segments of the Asian influenza virus (H2N2) gene that were circulating in 1957
were from duck flu virus, while the remaining five segments were from H1N1
human influenza virus.
The high variability of influenza A virus makes it more
difficult for people to cope with influenza.
People cannot accurately predict
the subtype of the virus that is about to spread, so they cannot be targeted
for preventive vaccination. On the other hand, every tenth Antigen shifts that
occur in the course of the year will even produce new strains of influenza that
have no vaccine at all.
Variation of influenza A virus antigen
Subtype name
|
Ranch
Antigen structure |
Ranch
Popular age Ranch |
Representative virus strain
|
Original A (A0)
|
Ranch
H0N1 |
Ranch
1930 - 1946 |
Ranch
A / PR / 8/34 (H0N1) |
Methylene type (A1)
|
Ranch
H1N1 |
Ranch
1946 -1957 |
Ranch
A / FM / 1/4 / (H1N1) |
Asian Type A (A2)
|
Ranch
H2N2 |
Ranch
1957-1968 |
Ranch
A / Singapore / 1/57 (H2N2) |
Hong Kong Subtype (A3)
|
Ranch
H3N2 |
Ranch
1968 - 1977 |
Ranch
A / Hongkong / 1/68 (H3N2) |
New A1 and A3 alternating type
|
Ranch
H3N2 H1N1 |
Ranch
1977 - present |
Ranch
A / USSR / 90/77 (H1N1) A / BeiJing / 32/92 (H3N2) |
*
Represents virus strain nomenclature: type / place of isolation / strain number
/ isolation date (subtype)
What is the Breeding Method of Influenza Virus?
Influenza virus can proliferate in the amniotic cavity and
allantoic cavity of chicken embryos.
The proliferating virus is free in
amniotic fluid or allantoic fluid and can be detected by a red blood cell
agglutination test.
Although influenza virus can proliferate in tissue culture
cells (human amniotic membrane, monkey kidney, dog kidney, chicken embryo and
other cells), it does not cause obvious CPE, and the presence or absence of
virus proliferation can be determined by the red blood cell adsorption test.
The susceptible animal is ferret. Continuous passage of the virus in mice can
increase virulence and cause extensive solid lesions or death in the lungs of
mice.
What are the Main Features of Influenza Virus?
Influenza virus has weak resistance and is not
heat-resistant. The virus can be inactivated at 56 ° C for 30 minutes.
Infectivity is quickly lost at room temperature. But it can survive for several
weeks at 0 ° C to 4 ° C, and it can survive for a long time below -70 ° C or
after lyophilization.
The virus is also sensitive to dryness, sunlight,
ultraviolet light, and chemicals such as ether, formaldehyde, and lactic acid.
What is the Way of Spreading of Influenza Virus?
The source of infection is mainly the patient, followed by
the recessive infection. The infected animal may also be a source of infection.
The main route of transmission is droplets with influenza virus that enter the
body through the respiratory tract. A few can also be infected by indirect
contact with a shared handkerchief, towel, etc.
After the virus is introduced into people, it is highly
contagious and can spread rapidly. The speed and breadth of the virus is
related to population density.
Viruses entering the human body, if not cleared
by cough reflexes or neutralized by specific IgA antibodies of the body and
non-specific inhibitors of mucosal secretions, can infect a few respiratory
epithelial cells, causing cells to produce vacuoles and degeneration And
progeny virions are quickly spread to neighboring cells, and then the virus
proliferation cycle is repeated.
The NA of the virus can reduce the viscosity
of the mucus layer of the respiratory tract, which not only exposes the cell
surface receptors and facilitates the adsorption of the virus, but also
promotes the spread of the virus-containing liquid to the lower respiratory
tract, causing damage to many respiratory cells in the short term.
Influenza
viruses generally cause only surface infections and do not cause viremia.
The target of influenza virus invasion is the epithelial
cells of the respiratory tract mucosa.
Occasionally, cases of invasion of the
intestinal mucosa can cause gastrointestinal influenza.
The virus invades the body by relying on hemagglutinin to
adsorb on the surface of the host cell and enter the cytosol through
swallowing; after entering the cytoplasm, the virus envelope and cell membrane
fuse to release the contained ss-RNA.
The eight segments of ss-RNA are in the
cytoplasm Internally encoded RNA polymerase, nuclear protein, matrix protein,
membrane protein, hemagglutinin, neuraminidase, non-structural protein and
other components.
Matrix protein, membrane protein, hemagglutinin,
neuraminidase and other encoded proteins in the endoplasmic reticulum M protein
and envelope are assembled on the Golgi body.
In the nucleus, the genetic
material of the virus is continuously replicated and forms the viral core with
nuclear proteins, RNA polymerases, etc.
Finally, the viral core is combined
with the M protein and envelope on the membrane and released after bud Outside
the cell, the cycle of replication is about 8 hours.
Influenza virus infection will cause host cell degeneration,
necrosis and even shedding, causing mucosal congestion, edema and increased
secretion, which will produce nasal congestion, runny nose, sore throat, dry
cough and other symptoms of upper respiratory tract infection.
When the virus
spreads to the lower respiratory tract, it may Causes bronchiolitis and
interstitial pneumonia.
The population is generally susceptible, and the length of
the incubation period depends on the amount of invaded virus and the immune
status of the body, which is generally 1 to 4 days.
After the onset, the
patient had symptoms such as chills, headache, fever, sore body, fatigue, nasal
congestion, runny nose, sore throat and cough.
Within 1 to 2 days after the onset
of symptoms, the amount of virus excreted with the secretion is large, and then
it decreases rapidly. Uncomplicated patients began to recover on the 3rd to 4th
day after onset.
If complications occurred, the recovery period was prolonged.
Influenza is characterized by high morbidity and low mortality.
Deaths are
usually caused by concurrent bacterial infections. Common bacteria include
Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenza, and so
on.
Complications are more common in infants and young children, the elderly,
and patients with chronic diseases (cardiovascular disease, chronic bronchitis,
and diabetes).
What is Influenza Virus Diagnosis Method?
Viral infection can also induce interferon expression and
cellular immune conditioning, causing some autoimmune reactions, including high
fever, headache, gastrocnemius and general muscle pain.
Toxin-like products of
viral metabolism and release products of cell necrosis can also cause and
exacerbate the above reactions.
Influenza virus infection reduces the ability of respiratory
mucosal epithelial cells to clear and adhere to foreign bodies, which greatly
reduces the body's ability to resist respiratory infections.
Therefore,
influenza often causes secondary infections, and secondary pneumonia caused by
influenza is fatal by influenza. One of the leading causes of death.
It is not difficult to diagnose influenza with clinical
symptoms in the epidemic period, but laboratory tests must be carried out to
confirm the diagnosis or epidemic surveillance, mainly including virus
isolation and culture, serological diagnosis and rapid diagnostic methods.
Isolation and identification of viruses
Usually take the patient's pharyngeal lotion or throat swab
within 3 days after the onset of infection, inoculate the 9-11 day-old chicken
embryo amniotic cavity and allantoic cavity after antibiotic treatment, and
incubate at 33 ° C to 35 ° C for 3 to 4 days before collecting amniotic fluid
Hemagglutination test with allantoic fluid.
If the hemagglutination test is positive,
then use a known immune serum to perform a hemoagglutination inhibition (HI)
test to identify the type.
If the hemagglutination test is negative, the
chicken embryos will be passaged 3 times blindly.
If hemagglutination still
cannot occur, the virus is judged to be negative.
Tissue culture cells (such as
human embryo kidney or monkey kidney) can also be used to isolate the virus,
and the presence or absence of virus proliferation can be determined using the
red blood cell adsorption method or the fluorescent antibody method.
What is Serological Diagnosis of Influenza Virus?
Take the patients' sera in the acute phase (within 5 days of
onset) and the recovery phase (course of 2 to 4 weeks), and HI test is commonly
used to detect antibodies.
If the serum antibody titer during the recovery
period is more than four times higher than the acute phase, a diagnosis can be
made.
Normal human serum often contains non-specific inhibitors, so trypsin can
be used to treat the serum before the HI test to avoid affecting the HI test
results.
The virus used in the HI test should be a strain that is closely
related to the current epidemic, and the reaction result can be accurate.
Complement fixation (CF) can only detect antibodies to NP and MP. These
antibodies appear early and disappear quickly. Therefore, the CF test can only
be used as an indicator of recent infection.
What is Rapid Diagnosis of Influenza Virus?
The rapid diagnosis of patients mainly uses indirect or
direct immunofluorescence and ELISA to detect viral antigens.
Frequently,
patients 'turbinate mucosa prints or smears of epithelial cells from
respiratory tracts are taken, immunofluorescent staining is performed with
fluorescein-labeled influenza virus immune sera to check antigens, or ELISA is
used to check antigens in patients' throat swabs.
Immunoenzyme-labeled
monoclonal antibodies can be used to rapidly detect viral particles or
virus-associated antigens of influenza A and B viruses in infected cells in
only 24 to 72 hours.
Methods such as PCR, nucleic acid hybridization, or sequence
analysis are also used to detect or type influenza virus nucleic acids.
What Precaution can I take against Influenza Virus?
How to prevent influenza: Influenza is an acute respiratory infectious disease caused
by influenza viruses. There are no specific antiviral drugs.
Early detection
and early medication can achieve better results. How to prevent it?
1. Improve autoimmunity
You can strengthen your body's immunity and fight viruses by
exercising it. Normal work and life, study and work should be combined with
work and rest, excessive fatigue, resulting in decreased resistance and
susceptibility to viral influenza.
Strengthen nutrition, balanced diet, diet
should be light, eat more vegetables and fruits rich in high vitamins, children
should not eat cold drinks.
2. Washing and Cleanliness
Insist on washing your face with cold water to enhance the
adaptability of the nasal mucosa to the air.
Keep abreast of weather changes
and add clothing to protect against the cold.
At the same time, strengthen
physical exercise to enhance the ability to adapt to the environment and the
body's immunity.
In addition, during the cold epidemic, try to go to less
populated places and wash your hands frequently.
When the body feels a little
unwell, mild dry mouth, take medicine immediately when nasal congestion, drink
plenty of water, pay attention to keep warm and rest, so that the condition
improves in time.
3. Body Temperature Regulation
Air conditioner should be cleaned before using the air
conditioner to avoid a large number of germs from blowing out with the wind.
The room temperature should be controlled above 24 ° C and the temperature
difference between indoor and outdoor should not exceed 7 ° C to avoid aggravating
the burden on the body's temperature regulation center. Pay attention to the
air conditioner or Do not blow directly on the head.
4. Improve Body Resistance
In summer, sweating and consuming a lot, you should add
enough nutrition to improve the body's resistance.
You can eat fish, meat,
eggs, milk, and legumes appropriately to supplement protein, eat more fresh
fruits and vegetables to get vitamin C, and eat more heat and damp food, such
as bitter gourd, peach, cucumber, mung bean, etc.
5. Preventive Drugs
After taking preventive drugs, the incidence of colds can
generally be reduced by about 50%. In addition, people with weak constitutions
can also be vaccinated in advance to prevent colds.
6. Pay attention to hygiene
Cleanliness and hygiene should be paid attention to prevent
illness from entering the mouth.
Wash your hands, take a bath, change your
clothes, and dry your bedding. The room is often ventilated. If you have a cold
patient, keep your distance! In cold seasons, try to avoid crowded places.
7. Learn related knowledge
Learn about the prevention and prevention of influenza, and
seek medical attention if you find a cold, so as not to delay your illness. At
the same time, you need to rest in bed, keep warm, reduce activities, and drink
plenty of water.
What are the Ways to Prevent Influenza Flu?
The quilt sheets should be washed and changed frequently, and
the quilt should be exposed to the sun to kill harmful bacteria.
When
going to
crowded places, it is best to wear a mask (preferably not to go). Keep
the air
in the room open and often open windows. Keep the room clean and
hygienic.
Climate changes quickly, remember to add or remove clothes, be
careful of the
cold.
Strengthen your physique, exercise, do some aerobic exercises, and
strengthen your body's immunity.
When you return home, remember to wash your
hands and try not to touch with dirty hands eyes, nose and mouth.
Eat a light
diet and don't eat too much spicy and cold food. For antiviral treatment, our
country already has localized oseltamivir phosphate.
Compared with imported
drugs, its efficacy and safety are equivalent. Coway not only has capsules, but
also innovates and develops granules for children.
When to get the flu vaccine?
It is best to get the flu vaccine in the fall, because autumn and winter have
large temperature changes, and it is a period of high flu. After the winter
arrives in spring, the flu will be gone.
The flu vaccine A single injection can
usually be administered for half a year, and the virus antibody can be produced
within half a month after the vaccine is injected, which can strengthen the
body's immunity and prevent illness at the peak of the flu.
Pay attention when
you have the vaccine. Remember to pay more attention during the peak of the flu
Rest, eat a light diet, strengthen your physique, and exercise.
What are the Methods of Prevention Against Influenza Virus Flu?
Comprehensive prevention
The prevention and control of influenza viruses must
strengthen the detection of influenza virus mutations and make accurate
predictions as far as possible for targeted vaccination.
On the other hand, cut
off the spread of influenza virus among the population.
Influenza viruses rely
on droplets to be detected as soon as possible. Influenza patients, fumigation
of chemical disinfectants in public places and other means can effectively
inhibit the spread of influenza virus.
For flu patients, drugs such as
interferon, amantadine, oseltamivir can be used for treatment, interferon is a
kind of inhibitor Viral replication cytokines, amantadine can act on influenza
virus membrane proteins and hemagglutinin proteins, preventing the virus from
entering host cells.
Oseltamivir can inhibit neuraminidase activity and
prevent mature viruses from leaving host cells.
There are also signs that
traditional Chinese medicines such as isatis root and Daqingye may have the
activity of inhibiting influenza virus, but it has not been confirmed by
experimental facts.
In addition to the treatment of influenza virus, more
treatments are directed at the symptoms caused by influenza virus, including
non-steroidal anti-inflammatory drugs, which can alleviate the symptoms of
influenza but not shorten the course of the disease.
Influenza is an abbreviation of influenza.
It is an acute
respiratory infectious disease caused by the influenza virus. It is transmitted
through droplets, which is fundamentally different from the common cold, and is
very harmful to human health.
Although, people can be attacked by the flu virus all year
round. But winter is a season of high incidence.
The weather is cold in winter,
the human body's resistance is weakened, and it is easy to be cold.
In
addition, people spend most of their time indoors, and the windows are often
closed. As a result, the air is not circulating and the virus is more likely to
spread.
In addition, the dry weather in winter reduces the resistance of the
human respiratory system, which can easily cause or aggravate respiratory
diseases.
In fact, as long as we take appropriate exercise, pay
attention to a reasonable diet, and strengthen our physical resistance, flu can
be completely prevented.
Here's how to boost your immunity and fight against
the flu virus.
What is the Method of diet when I have Influenza?
Drinking more water can keep the mucous membranes in the
mouth and nasal cavity moist, and can effectively play a role in removing
bacteria and viruses.
Eat more protein-rich foods
The main substance of the human immune system is
immunoglobulin. When the human body lacks protein, it will greatly reduce the
number of lymphocytes in immune cells and insufficient synthesis of immune
substances, resulting in a serious decline in immune function.
Protein is
mainly obtained from animal foods, such as beef, skinless chicken breast, egg
white, milk, shrimp, etc.
Eat more iron-containing food
Studies of iron-rich foods have found that people with iron
deficiency have lower immunity.
When the content of iron in the human body is
insufficient, the content of T cells in the immune system that controls and
regulates will decrease, resulting in the inability of the immune system to
function effectively.
In addition, iron is an important component of
hemoglobin.
Increased iron intake can promote the synthesis of hemoglobin,
promote peripheral circulation, and avoid cold hands and feet.
Because the feet
are more sensitive to temperature, if the feet are cold, they will cause the
nasal mucosa to constrict and reflect, making people vulnerable to the flu
virus.
Foods rich in iron are mainly animal liver, meat, pig blood, duck blood,
eggs, dark vegetables and so on.
Eat more zinc-containing foods
Zinc-rich foods Zinc can activate more than 200
life-threatening hormones and enzymes, helping the immune system to exert its
maximum defense.
Zinc deficiency will reduce the level of immune globulin in
the body, reduce the body's ability to prevent it, and increase the risk of
various epidemics, including influenza.
Foods rich in zinc include oysters,
crabs, beans, beef, mutton, dried fish, scallops, pork liver, wheat germ and so
on.
Vitamins
Vitamin A can maintain the stability of respiratory mucosal
epithelial cells. Vitamin C and Vitamin E are antioxidants that are naturally
present in foods. They can remove free radicals that are harmful to our body
and strengthen our body's resistance.
B vitamins participate in energy
metabolism in the body, promote protein synthesis, and play a very important
role in the normal maintenance of physiological functions.
These vitamins are
abundant in foods such as vegetables, fruits, cereals and beans.
Self-healing method
The human body can produce specific cellular and humoral
immunity after being infected with influenza virus or after vaccination.
Anti-HA and anti-NA are specific antibodies to influenza.
Anti-HA is a
neutralizing antibody, so the occurrence of anti-infection is related to
anti-HA, while reducing disease and preventing virus transmission is related to
anti-NA.
Anti-NP has type specificity and can only be used to isolate the
virus.
Serum antibodies and sIgA antibodies in nasal secretions are related to
protection.
Locally secreted antibodies may be the most important factor in
preventing infection. People with a certain antibody titer may be infected but
mildly ill.
The three types of influenza viruses are not antigenically linked
and therefore cannot induce cross protection.
People with high antibody titers
to the virus can develop mild infections with the new strain when antigenic
drift occurs in the type of the virus.
Serum antibodies can last for months to
years, while secreted antibodies persist for a short period, usually only a few
months.
The cellular immune response is mainly that specific CD4 + T
lymphocytes can help B lymphocytes to produce antibodies, and CD8 + T cells can
lyse infected cells, reduce the amount of virus in the lesion, and help recover
the disease.
It is worth noting that the CD8 + T cell response is cross-cutting
(which can lyse cells infected with any strain), does not have strain
specificity, and may mainly directly affect viral nucleoproteins rather than
glycoproteins on the surface of the virion.
In addition to infecting humans, influenza A viruses can also
infect birds, pigs, horses, and other animals; influenza B viruses only infect
humans.
Influenza C viruses are endemic in both humans and pigs. According to
viral gene evolution studies, all mammalian influenza viruses are derived from
avian influenza viruses.
Different animal influenza viruses have different
genetic evolution rates. The HA and NA genes of human influenza A viruses have
evolved the fastest, while avian influenza viruses have slower evolution.
What is the Prescription Vaccination for Influenza Virus?
Influenza viruses are highly contagious, spread rapidly, and
can easily cause a pandemic.
In addition to strengthening influenza,
strengthening physical fitness, maintaining room hygiene, avoiding crowd
gathering during epidemics, and necessary air disinfection in public places.
Vaccination can significantly reduce the incidence and symptoms. However, due
to the continuous mutation of influenza virus.
Only by constantly grasping the
dynamics of influenza virus mutation and breeding of new epidemic virus
strains, can a vaccine with specific preventive effect be prepared in time.
The
vaccines used are inactivated vaccines and live attenuated vaccines.
According
to reports, live attenuated vaccines on the market are vaccine strains produced
by crossing temperature-sensitive attenuated strains (Ca) A AnnArbor / 6/60
(H2N2) with H1N1 or H3N2 wild strains.
The B / Sichuan / 379/99 representative
strain in Sichuan, China has been recommended by WHO as a preventive vaccine
for the global influenza season in 2001-2002.
The advantage of inactivated vaccine is that it is injected
subcutaneously, which can produce a large amount of IgG, and has small side
effects.
The disadvantage is that there are fewer local sIgA and more
vaccination times.
The live attenuated vaccine is inoculated using the
nasopharyngeal spray method. Although the operation is simple and convenient,
and there are more local SIgA, it has large side effects, similar to mild
infection.
The developed HA and NA subunit vaccines have small side
effects, can inhibit virus replication and transmission in the respiratory
tract, and can reduce clinical symptoms.
A lot of research on genetic engineering vaccines of influenza virus has been carried out abroad.
The HA
gene of influenza virus was recombined into the vaccinia virus gene by genetic
recombination, and a recombinant vaccine was made and expressed. It was
confirmed that specific antibodies could be produced by animal vaccination.
There is no effective treatment, mainly symptomatic treatment
and prevention of secondary bacterial infections.
On June 11, 2018, a quadrivalent influenza virus split
vaccine was approved for marketing in China to prevent influenza virus
infection in people aged 3 years and over. In addition to A1, A3, and BV
viruses, they also include BY type influenza viruses.
Main hazard
Studies have found that winter flu can double the risk of
heart disease and stroke. During the first week of respiratory disease, the
risk of heart disease and stroke more than tripled.
A study in the UK showed that influenza can lead to increased
deaths from coronary heart disease because the inflammation it causes disrupts
the smoothness of "sleeping" clots in the arteries.
The risk of
people dying from a heart attack after catching the flu has risen by a third.
Researchers have found that acute pneumonia caused by influenza infection can
disrupt the stability of the atherosclerotic plate in the arteries.
The
atherosclerotic plate is a hard deposit of cholesterol and fibrous tissue that
accumulates on the walls of blood vessels. When they divide, they release
clots, impeding blood flow to the heart and causing a heart attack. The results
of a study in the United States show that the flu vaccine can not only enhance
the immunity of vaccinators against cold viruses, but also prevent heart
disease and stroke.
A study by the University of Texas showed that people with
a heart attack are 67% less likely to have another heart attack after getting a
flu shot than those without a vaccination.
As the body fights viruses or
infections, the arterial aggregates become inflamed, which can lead to a heart
attack. After being vaccinated, they can fight the flu virus and receive the
power to prevent heart attacks.
Experiments conducted by the Los Angeles
Samaria Hospital Heart Research show that heart attacks are particularly high
in winter and fewer in summer, with an average reduction of 15% -22%.
Mortality
is also high in winter.
The reason may be that the weather is warm in summer and
the cold in winter.
At this time, the blood coagulation factors are more active
and the blood is thicker.
Studies conducted by the University of Maryland have
also shown that patients with a built-in defibrillator require more shocks in
the winter or spring to suppress cardiac arrest.
There were 40% more shocks
than in summer and autumn.
Researchers say influenza can trigger a fatal heart
attack. The report shows that flu can worsen heart disease, and there is a
significant increase in deaths from heart attacks during the flu season.
In the
United States alone, this number is as high as 90,000 per year.
US researchers pointed out at the annual meeting of the
American College of Cardiology that getting the flu shot and staying warm
during the winter can help reduce the risk of a heart attack.
Most people with heart disease in our country do not realize
that they are at high risk of heart disease-related complications caused by the
flu, and there are only a few flu vaccine vaccinators.
The flu epidemic in China
usually starts in December or January and lasts for two months. For this
reason, it is still the best time to get an annual effective flu vaccine.
What is the Research progress regarding Influenza virus?
US researchers say they have found a new anti-flu drug that
can stop those resistant strains from multiplying, giving hope for flu
treatment. A report published in the journal Science said that researchers have
achieved effective results in experiments on mice. Researchers are currently
experimenting with other animals to test its efficacy.
The new drug stops an important enzyme on the surface of the
influenza virus (neuraminidase), preventing it from invading other cells. This
enzyme makes a connection between the flu virus and human cells, and then
infects new cells.
The new anti-flu drug developed by scientists can permanently
attach to the enzyme, block its movement, and then prevent the virus from
spreading to infect other cells.
Scientists call this new drug DFSAs. Due to
the effect of the drug, if the influenza virus wants to continue to move and
reproduce, it can only destroy itself first, so it cannot infect other cells.
What are the Important events regarding Influenza Virus Disease?
H1N1 super virus produced by Japanese scholars approved for
madness, human infection will undoubtedly die
In July 2014, in order to analyze the genetic change of the
influenza virus H1N1, Yoshikawa Kazuo, a professor at the University of Tokyo
in Japan and the University of Wisconsin in Madison, developed a new variant.
The modified H1N1 can bypass the human immune system and is considered Super
virus. Once this life-threatening virus is leaked, humans will be unable to
resist and may cause a huge disaster. Kawaoka said he did develop the superflu
virus.
He said that the preliminary research report has been submitted to the
World Health Organization Committee and has been well received.
However, many scientists are still cautious about this. Some
scientists believe that it is too crazy for Hegang to extract superhuman
viruses from virus strains and create super viruses.
U.S. scientists make deadly flu virus controversial, could
cause pandemic.
On June 11, 2014, U.S. scientists said they used a piece of
flu gene that was circulating in wild ducks to create a deadly virus that was
extremely similar to the Spanish flu virus.
Although the researchers believe
the results will help deal with the next flu pandemic, the experiment was still
criticized by some as reckless, crazy and dangerous. The experiment was led by Yoshihiro Kawaoka, a professor
of virology at the University of Wisconsin-Madison.
In 2011, he and the Dutch
medical scientist Ron Fuhiye studied how the ability to spread the H5N1 avian
influenza virus would increase, but its experiments.
The method has been
criticized. The related experiments were suspended for one year, and they were
not restarted until 2013.
Experiments with ferrets show that the new virus is more
pathogenic than ordinary bird flu viruses, but lower than the Spanish flu virus and cannot be transmitted by droplets.
Ferrets are often used to
test for the hazards of the influenza virus because of some of their
respiratory-like characteristics.
As long as the 7 amino acids of some of the
key proteins of the new virus are mutated, its transmission ability will be
significantly improved. Ferrets can be easily transmitted through the air.
Researchers believe that the new virus has the potential to cause an influenza
pandemic in the population.
Professor Robert May, former chairman of the Royal Society,
still told the media that the work was "completely crazy" and that
the whole incident was "extremely dangerous." Harvard professor Mark
Lipsic expressed similar concerns:
"Even in the safest laboratory, this is
dangerous behavior. Scientists should not take such risks unless there is
strong evidence that their work can save lives, but their paper did not
provide.
One view is that the H1N1 influenza virus that caused many people to
die or even die was caused by a laboratory accident.
Why can masks prevent influenza virus 25 times smaller than PM2.5?
It's not that simple. It has no evidence but a convention.
Conclusions you can draw
In the winter, the flu often rages. How to prevent flu
scientifically? Can anti-fog masks protect against the flu virus?
Influenza is
generally caused by a virus. Let's take a look at what a virus is. Can wearing
a mask filter out the flu virus?
Moderate humidity air can help to
resist the spread of influenza. One is to help the virus to settle, and the
other is to enhance the activity of respiratory mucosal secretions.
Author's Bio
 |
| Dr. Shawna Reason |
Education: MBBS, MD
Occupation: Medical Doctor / Virologist
Specialization: Medical Science, Micro Biology / Virology, Natural Treatment
Experience: 15 Years as a Medical Practitioner
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