Swine Influenza
The new outbreak in Human, Why now? :
1. Is it a type of God punishment?
2. Is it developed because of Environmental pollution.
3. Is it a Natural genetic mutation.
4. Is it cloned in a biological weapon lab.
The Virus Characteristics
1. The virus is Influenza Virus A, H1N1.
2. The virus caused Spanish Flu in 1918 and killed 40 to 100 millions individuals.
3. The virus kills directly by massive hemorrhages and edema in lungs.
And indirectly by secondary infections.
4. Its genetic structure is RNA consists of 8 segments.
5. Its genes code for 11 proteins of which 3 important surface proteins, namely Neuroaminidase, Hemagglutinins, and M2 ion channel proteins.
6. HA and N proteins are recognized by host antibodies and the viral serotyping depends on them.
7. M2 and N proteins are targets of the antiviral drugs.
8. Hemagglutinins mediates binding of the virus to the target cells
9. Neuroaminidaseis an enzyme involved in the release of the virus from infected cells
10. Swine flu is not an accident from a lab. WHO says.
11. In 2005 H1N1 genome was published in the journal Scienc Dr. Taubenberger noticed that the change in amino acids of the virus
( 25-30 out of 4400 )will result in a change of
bird virus into a killer virus spread from
person to person.

Risky Groups for Influenza A virus subtype H1N1
1. Younger than two years and older than 65 years people.
2. People of any age with certain medical conditions, such as chronic heart, lung, kidney, liver, blood, or metabolic diseases.
3. Health care workers.
4. People working with pigs.
5. Young age people!
Transmission of the disease
1. Aerosoles containing the virus from sneezes and coughs.
2. Direct contact.
a. Touching of contaminated door handles and
phones and then touching your own mouth,
nose, or eyes.
b. Greeting by Kissing!
3. From mucus, nasal secretions, blood , and stool.
4. Patients discharge viruses one day before getting the symptoms to approximately 5 days after the symptoms start.
5. Flu virus remain infectious for about::
a. One week at body temperature.
b. Over 30 days at 0 C.
c. Indefinitely at very low temperatures
6. The virus is inactivated easily by disinfactants and detergents.
Key Elements for Protection
1. Use medical masks.
2.Use hand hygiene.
3.Dealing with patients:
a. Use medical masks and eye protection (goggles).
b. Use gown and clean gloves.
4. Respiratory hygiene:
Health-care workers, family members should cover mouth and nose with tissue when coughing or sneezing.
5. Stay home and avoid kissing or contacting people when you have fever with respiratory symptoms.
6. Use strict sanitary measurements at home when any one has flu like symptoms. Health-care workers should be vaccinated. Treatment can be taken prophylacticly when there is outbreak .
7. Treat any waste as infectious clinical waste.
8. Family members and visitors should limited.
Immunity to the Virus
There are two types of Immune
Responses:
1. Natural (unspecific) response.
2. Acquired (specific) response.
There are two types of acquired Immune Responses:
a. Primary immune response.
b. Secondary immune response.
Viral Infection
It is a biological process controlled by
many factor such as:
1. Virulence of the virus.
2. The infective dose of the viral particles.
3. The immunological status of the host.
4. Previous challenge
Genetic Diversity of Influenza A virus
New influenza A viruses are constantly being produced by mutations or reassortment:
1. Because of absence of Proofreading enzymes, every newly manufactured influenza virus will contain a mutation in the genome.
2. Mutations can cause small change in HA or N antigens on the surface of the virus. This is called antigenic drift.
3. 2. Influenza virus ca reassort and may acquire new antigens from avian, swine or from other species. This is called antigenic shift.
Vaccines and Vaccination
The most common vaccines are two types:
1. Flu killed injectable vaccine.
2. Live attenuated influenza virus nasal spray vaccine. It is not recommended for under
age 2 or over age 50.
3. The virus strains chosen by the WHO are:
a. Influenza A H1N1.
b. Influenza A H3N2.
c. Influenza B.
Most common influenza vaccines are trivalent contain two influenza A subtypes and one influenza B strain.
A vaccine formulated for one year may be ineffective in the following year, since influenza virus evolves rapidly.
WHO recommends a vaccine composition that targets the three most representative strains in circulation.
Vaccine can protect 70 to 90% of influenza specific illness.
Among adults, the vaccine reduces the severe illness and complications by up to 60% and deaths by 80%.
It is most effective when there is matching between the vaccine viruses and the circulating virus.
Annual reformulation of the vaccine : due to high mutation rate of the virus, the WHO recommend yearly reformulation of the vaccine according to the most circulating strains.
Treatment
Since Influenza is caused by virus,antibiotics have no effect on infection, unless prescribed for secondary bacterial infection.
Antiviral medication is sometimes effective, but viruses ca develop resistance to standard antiviral drugs.
There are two classes of antiviral drugs:
1. Neuroaminidase inhibitors. Oseltamivir (Tamiflu), and Zanamivir.
2. M2 inhibitors (adamantanes). Amantidine and rimantidine.
Neuroaminidase Inhibitors
Neuroaminidase inhibitors,Tamiflu and
Relenza are effective as following:
1. They stop the spread of the virus in the body.
2. They are effective against both influenza A and B.
3. They reduce the symptoms and complications.
4. The viruses have low resistance as compared to other class the M2 inhibitors.
M2 Inhibitors (Adamantanes)
M2 inhibitors, amantadine and rimantadine are designed to block a viral ion channel ( M2 protein) and prevent the virus from infecting the cells:
1. They are effective mainly against Influenza B, but sometimes against A.
2. The virus has great resistance to these drugs reaching to 91% as used in 2005 against H3N2 subtypes.
Control Measures
1. Annual Influenza vaccination.
2. Implementation of standard and droplet precautions.
3. Active influenza testing for new illness cases.
4. Restriction of ill visitors and personnel from entering the facility.
5. Administration of influenza antiviral medication for prophylaxis and treatment when influenza detected in the facility.
6. Other respiratory and cough etiquette programs.
Most Frequent Questions
1. How long do the contaminated materials stay infective?
2. Is there any reliable treatment?
3. Is there any reliable vaccine?
4. Can the infection be transmitted from food materials?
5. Can the infection transmitted from human to human?
6. Why does the disease appear now?
7. Is it possible for the disease to occur in our region?
8. Is the virus cloned in a biological weapon lab.?
9. How do we disinfect the contaminated materials?