A video for better understanding(:

Here's a short clip for a better understanding on herpes.

Treatment

There are no cure for herpes.

However, there are medications that significantly reduce the frequency and duration of outbreaks. These medications have few side effects in most people.
There are 3 prescriptive medications They work by interfering with DNA synthesis to prevent the virus from reproducing. Herpes treatment options include:

• Acyclovir (Zovirax): This is the oldest and there is a generic of this medication so it is cheaper.





• Famcyclovir (Famvir)

• Valacyclovir (Valtrex): There should be a generic of this medication in approximately one year.
  
  
  
  
  
  

All of these medications are effective in suppressing HSV 1 and HSV 2 and can be taken episodically or continuously.

Episodic therapy

This means taking the medication when there is an outbreak or feel a sore coming on.If the treatment is soon enough, the drugs can lessen the severity and shorten the healing time.

Suppressive therapy

This means taking the medication continuously to prevent an outbreak or a sore.Up to 70 percent of new cases of herpes are transmitted from someone showing no apparent symptoms at the time they infect their partner. This is called asymptomatic shedding of the virus. When taken suppressively, the drugs don't always prevent outbreaks, but help them to occur less frequently

Symptom relief

• Wear loose clothing.
• Wear cotton underwear.
• Urinate in the tub or pour water over the genitals while urinating.
• Use a drying agent in your tub water. You can sprinkle cornstarch lightly on your genitals while in the tub. Soak twice a day for 15 minutes.
• Tannic acid found in black tea has been found to reduce itching and pain. Place a moist tea bag over the sore.
• Ice packs to the lesion may be soothing.

Prevention

STOP RISKY BEHAVIOUR
AVOID SEXUAL CONTACT WHEN SIGNS OR SYPTOMS ARE PRESENT!

Diagnosis

Methods of testing include diagnosis by:

• Viral Culture
• Serologic tests (Blood tests)
• Antigen Tests

Viral Culture

Viral culture looks for the presence of the virus in the lesion.

Viral culture is very specific:

• it does not frequently give a positive result when something else is the culprit



• it can also be very sensitive if the specimen is adequate



• it also provides a way to tell whether the infection is caused by HSV-1 or HSV-2

Lots of people need to be tested more than once. The viral culture often misses herpes even when it is present. Often a patient who has received a negative culture result will be asked to come back again when a new genital lesion appears so the culture can be tried a second or third time.

Serologic Test(Blood tests)

They detect "antibodies. " These are substances produced by the immune system to fight off infection.
Blood Tests detect herpes by looking for antibodies in the blood or serum. Blood tests can be performed even when no symptoms are present. If antibodies are found in the blood, herpes simplex is latent in the body. Blood tests do not require swabbing a lesion, so they can be done long after symptoms have faded.
The sensitivity and specificity of blood tests is better than culture or antigen tests, but there are two important factors to consider.
The first factor is timing. If this is the first exposure to herpes, a person may take several weeks to develop the antibodies that the test looks for.
The second is that some blood tests cannot tell the difference between the two types of herpes, HSV-1 and HSV-2. For this reason, anyone seeking an accurate diagnosis of genital herpes must be sure to get a "type-specific" serologic test, which can accurately distinguish HSV-2 from HSV-1 antibodies. Most commercially available kit assays currently cannot make this distinction despite their claims.

Antigen Detection Tests

This is where components of the virus are specifically identified.It is used less frequently.It dentify herpes by the presence of antigens, fragments of the virus that are known to stimulate the immune response.
A swab is taken similar to the method used for viral culture. In general, antigen detection assays are less sensitive than viral culture. Antigen-detection is usually done only in research laboratories or large reference laboratories.
Antigen tests can produce results more quickly than cultures and are sometimes less expensive. However, better samples are needed than for cultures and many do not determine whether the sample is infected with HSV-1 or HSV-2.

Symptoms of Herpesviridae

The symptoms of genital herpes vary greatly from person to person, with many people having no noticeable symptoms (asymptomatic).

The first outbreak...
Symptoms:

• usually develop within 2 to 20 days after contact
• could continue up to 2 weeks
• may be so mild it goes unnoticed
• may take longer or be less severe in some people, especially in those with partial immunity to the virus from having facial herpes, e.g. cold sores.
• in the first attack sometimes causes visible sores
• last between 10 - 21 days

Initially,antibodies will not be produced because people have yet to be exposed with this virus. Once the herpes virus gets into skin cells,it reproduce and replicates, making the skin red and sensitive. Blisters or bumps may appear on genital area.


Other symptoms include:

• swollen lymph glands
• painful inflamed blisters develop around infected area
• headache
• muscle ache
• fever
• vaginal or penis discharge
• infection of the urethra causing a burning sensation during urination
• a burning sensation in the genitals
• lower back pain
• small red bumps may appear in the genital area following earlier symptoms, later developing into painful blisters, which crust over, form a scab, and heal.

Up to 60% of people who have genital HSV show no signs of the disease and are unaware that they are infected, but are capable of transmitting the virus to others (asymptomatic viral shedding).

Those who have obvious symptoms will continue to have subsequent recurrence. However, it will not be as painful as before

Recurrences:

• are usually shorter and less severe than the initial episode
• may decrease in both severity and frequency over time
• are usually preceded by warning symptoms (also known as prodromal symptoms)
• After the lesions have healed, and the symptoms of recurrence have ended, pain and discomfort in the genital area is still sometimes felt (post-herpetic neuralgia).

Signs of Recurrent Outbreaks:

• Breaks or irregularities in the skin, such as a cut, red bump or rash
• Small sores or blisters that form a crust may occur anywhere in the region between the legs--thigh, buttocks, anus, or pubis

Cycle of a typical outbreak or recurrence

The symptoms of an active herpes outbreak or recurrence may occur in the following phases.

1.Inflammation
Swelling, tenderness, and/or redness that may appear before the actual outbreak, and may include itching, and sensitivity. The inflammation may never progress to blisters.

2.Blisters
One or several small fluid filled lesions, tiny red bumps, or rash may form and can resemble small fissures, especially near the anus.

3.Ulcers
When the skin breaks on the blisters, small, round, wet looking, ulcers leaking clear to milky colored fluid can be seen

4.Crust
The sores begin to dry, scab, and crust over beginning the healing process. The virus may possibly still be present until the ulcer has completely healed, and the scab falls off.

5.Healing
New skin is formed and may look slightly red, or silver. Viral replication is complete, the virus has left the skin's surface, and the skin is now safe to touch. Healing of the skin does not normally leave scarring. The virus then retreats into the nerves and lies dormant.

Viral Disease & Host defence

Transmission

Genital herpes can be transmitted with or without the presence of sores or other symptoms, and is often transmitted by people who are unaware that they are infected.

Transmission of Oral Herpes



Oral herpes (usually HSV-1) has been detected in both the saliva and blood of patients with active oral infections. It is most likely to occur during preschool years. Oral herpes is easily spread by direct exposure to saliva or even from droplets in breath. Skin contact with infected areas is sufficient to spread it. Transmission most often occurs through close personal contact, such as kissing. In addition, because HSV-1 can be passed in saliva, people should also avoid sharing toothbrushes or eating utensils with an infected person.


Transmission of Genital Herpes


Genital herpes is most often transmitted through sexual activity, and people with multiple sexual partners are at high risk. HSV, however, can also enter through the anus, skin, and other areas.
People with active symptoms of genital herpes are at very high risk for transmitting the infection. Unfortunately, evidence suggests about one-third of all HSV-2 infections occur during times when the virus is shedding but producing no symptoms. In addition, only about 10 - 25% of people who carry HSV-2 actually know that they have the infection. In other words, most people either have no symptoms or don't recognize them when they appear.


Herpes can be spread by any of the following real-life situations:

• Kissing someone if you have a cold sore can transfer the virus to any part of the body that you kiss them (including inside of the mouth and throat, or the genitals)
• The virus can be transmitted to your partner if you have active genital herpes and have vaginal or anal intercourse.
• If you have a cold sore and put your mouth on your partner's genitals (oral sex), your partner can be infected with genital herpes. Consequently, oral sex should definitely be avoided if one partner has a facial herpes attack.
• People who experience an episode of herpes, either facial or genital, should consider themselves infectious from the first sign of an outbreak to the healing of the last ulcer.
• Occasionally, one partner in a long-term relationship may develop symptoms of herpes for the first time. Often this is due to one or both of the partners being asymptomatic carriers of HSV and not knowing it.
• A mother can pass the virus onto her baby during pregnancy or at birth.
• One kind of complication involves spreading the virus from the location of an outbreak to other places on the body by touching the sore(s). The fingers, eyes, and other body areas can accidentally become infected in this way. Preventing self-infection is simple. Do not touch the area during an outbreak. If you do, wash your hands as soon as possible with soap and warm water.
• Reports have been sited of possible transmission via 'Hot tubs" but there is scientific skepticism as to whether or not the virus can be transmitted via inanimate objects such as toilet seats.
• It is generally considered that the spreading of genital herpes through inanimate objects, such as soap, towels, clothing, bed sheets, toilet seats, and spa surfaces is highly unlikely because the herpes virus cannot live very long outside of the body.

What is Herpesveridae??

Herpesviridae is an infection caused by the herpes simplex virus.It affects the skin and nervous system and produces small temporary (but sometimes painful) blisters on the skin and mucous membranes.




Viral Structure & Classification

It is a Family of double-stranded DNA viruses that consist of a spherical virion having the DNA packaged in a liquid crystalline array in a central core surrounded by an icosahedral capsid, an amorphous tegument, and an envelope consisting of a lipid bilayer closely associated with the amorphous protein layer.



Herpesviridae Subfamilies
Alphaherpesvirinae. Members of this subfamily are neurotropic (infect nervous system tissue), have a short reproductive cycle (~18 hr.) with efficient cell destruction and variable host range.


Common name Scientific name Disease they cause

Herpes simplex virus 1 Human herpesvirus 1 facial, labial and ocular lesions

Herpes simplex virus 2 Human herpesvirus 2 genital lesions

Varicella-zoster virus Human herpesvirus 3 chickenpox and shingles




Chicken Pox Facial lesion



genital lesion

Betaherpesvirinae. Members are lymphotropic, have a long reproductive cycle, restricted host range and infected cells become enlarged (cytomegalo).

Common name

• Human cytomegalovirus

Scientific name

• Human herpesvirus 5

Disease they cause

• infectious mononucleosis

effects of mononucleosis


Common name

• (no common names)

Scientific name

• Human herpesvirus 6 & 7

Disease they cause

• mild early childhood roseola

Gammaherpesvirinae. These herpesviruses are also lymphotropic and specific for either T or B lymphocytes.

Common name

• Epstein Barr virus

Scientific name

• Human herpesvirus 4

Disease they cause

• cofactor in human cancers

HERPESVIRIDAE!!!

HOLA people!! My first entry is going to be about herpesviridae!!!

What you will learn

• What is Herpesviridae?
• How it trasmits?
• The symptoms
• Diagnosis
• Treatment
• Precautionary Action to avoid getting Herpes
  

Parts of Hepatitis B virus

Hepatitis B under a electron-microscope

Drawing of Hepatitis B virus

Treatment of Hepatitis B

Acute hepatitis B

• No specific treatment
  
• Care is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids that are lost from vomiting and diarrhoea.
  

Chronic hepatitis B

• Treated with drugs, including interferon and anti-viral agents, which can help some patients
• Cost thousands of dollars per year and is not available to most patients in developing countries.

Liver cancer is almost always fatal, and often develops in people at an age when they are most productive and have family responsibilities. In developing countries, most people with liver cancer die within months of diagnosis. In higher income countries, surgery and chemotherapy can prolong life for up to a few years in some patients.

Patients with cirrhosis are sometimes given liver transplants, with varying success. 

Transmission of Hepatitis B

Hepatitis B virus is transmitted between people by contact with the blood or other body fluids (i.e. semen and vaginal fluid) of an infected person. It has the same way of transmitting the virus like the human immunodeficiency virus (HIV), but HBV is 50 to 100 times more infectious. Unlike HIV, HBV can survive outside the body for at least 7 days. During that time, the virus can still cause infection if it enters the body of a person who is not infected.

Common modes of transmission in developing countries are:

• perinatal (from mother to baby at birth)
• early childhood infections (inapparent infection through close interpersonal contact with infected household contacts)
• unsafe injections practices
• blood transfusions
• sexual contact

In many developed countries (e.g. those in Western Europe and North America), patterns of transmission are different than those mentioned above. Today, the majority of infections in these countries are transmitted during young adulthood by sexual activity and injecting drug use. HBV is a major infectious occupational hazard of health workers.

HBV is not spread by contaminated food or water, and cannot be spread casually in the workplace.

The virus incubation period is 90 days on average, but can vary from about 30 to 180 days. HBV may be detected 30 to 60 days after infection and persist for widely variable periods of time.

Symptoms of Hepatitis B

Hepatitis B virus can cause:

·         acute illness with symptoms that last several weeks

·         yellowing of the skin and eyes (jaundice)

·         dark urine

·         extreme fatigue

·         nausea

·         vomiting

·         abdominal pain

People can take several months to a year to recover from the symptoms. HBV can also cause a chronic liver infection that can later develop into cirrhosis of the liver or liver cancer. 

Hepatitis B

Key facts

• Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease.
• The virus is transmitted through contact with the blood or other body fluids of an infected person - not through casual contact.
• The hepatitis B virus is 50 to 100 times more infectious than HIV.
• Hepatitis B virus is an important occupational hazard for health workers.
• Hepatitis B is preventable with a safe and effective vaccine.

Poxviridae

History:

• 1200 B.C. small pox killed pharaoh Ramses V.
• Spanish decimated the Aztecs in the 16th century.
• Edward Jenner found a vaccination for smallpox in 1796.
• WHO vaccination program in 1950. WHO declared small pox eradicated in 1980

Structure of viruses and its classification:

• Smallpox and vaccinia belongs to a group of viruses called orthopoxvirus.
  
• Largest family of viruses.
• has a unique oval shape.
• Antigenically complex.
• can remain stable in air for hours.
• linear dsDNA.

Viral disease and host defense:

• can attack humans only.
• can be spread by respiratory secretions.
• always associated with skin lesions.
• at least 9 pox viruses cause disease in humans.
  
• 12-7 days of incubation.
• influenza-like symptoms initially .
• characteristics pustules.
• scarring of skins.
• neurological damage.
• blindness
• death

Molecular biology research and viral therapy:

• Edward Jenner was the one that found the vaccination for small pox. he used cowpox from milkmaids and vaccinated 8 year old James Phipps. he then challenged smallpox.
• vaccinia can be evolved from cowpox or smallpox. they can also be used as a vector.
• smallpox can be eradicated because there is no other reservoir for the virus other than humans.
• the virus causes only acute infection from which the patients dies, or he obtains lifelong immunity.
• the virus is also an effective immunogen.
• the virus is not infectious during incubation but during its symptoms.
• it can be spread by aerosol or air droplets.
  
• best defense is vaccination.

Other uses of poxviridae:

• smallpox is used by terrorists to cause an outbreak in countries that they intend to terrorize.
  

Rhinovirus

Rhinovirus

Viral Therapy

There are no medicines that will cure the common cold. Given time, the body's immune system will make antibodies to fight the infection and the cold will get better on its own. Antibiotics have no effect on colds because they do not kill viruses. A very large number of medications are available for the treatment of cold symptoms. These include antihistamines, decongestants, and pain relievers.

· Antihistamines block the action of histamine. They relieve sneezing, runny nose, itchy eyes, and congestion. Side effects include a dry mouth and drowsiness. For this reason, antihistamines should not be taken by people who must drive or operate heavy machinery.
· However, aspirin should never be given to children younger than 12, and all kids and teens under age 19 shouldn't take aspirin during viral illnesses, because such use may increase the risk of developing Reye syndrome, a rare but serious condition that can be fatal.
· Decongestants reduce blood flow and shrink tissues in the nose and make it easier to breathe. A side effect is nervousness and an inability to sleep. People with heart disease and high blood pressure should not use decongestants.
· Nasal sprays and nose drops can also help to reduce nasal congestion. These products are used to apply a decongestant directly to the nose. It can take effect and act more strongly, therefore, than decongestants in pills or liquids. One problem with nasal sprays and nose drops is that people may become dependent on them. Once an individual stops using the products, he or she may experience withdrawal symptoms. For that reason, nasal sprays and nose drops should not be used for more than a few days.

Cold symptoms can also be relieved by some simple self-care steps. These include:
~Drinking plenty of fluids, but avoiding acidic juices (such as grapefruit juice) that may irritate the throat
~Gargling with warm salt water for a sore throat
~Not smoking
~Getting plenty of rest
~Using a cool-mist room humidifier to ease congestion and sore throat
~Rubbing a lubricant such as Vaseline under the nose to prevent irritation from frequent nose-blowing
~Removing mucus from the nose of infants who are too young to blow their noses. Infant nasal aspirators are available for this purpose

Rhinovirus

Molecular Biology Research

RESEARCHERS FIND THAT HOTEL GUESTS WITH COLDS CAN LEAVE THEIR GERMS BEHIND AFTER CHECK OUT

A group of researchers led bya team the University of Virginia Health System found that adults infected with rhinovirus, the cause of half of all colds, may contaminate many objects used in daily life, leaving an infectious gift for others who follow them. The experiments, conducted in hotel roomsin San Francisco, Califonia. Most are aware that handshaking and other forms of skin to skin contact can result in catching someone else's cold, but many may assume that viruses can't live long on hard surfaces in living environments.

Dr. Owen Hendley, professor of pediatrics in the Division of Pediatric Infectious Diseases at the UVa Health System who will present the research, cautions that this assumption may not be completely true."To my surprise, in a hotel room occupied overnight by an adult with a cold, everything from television remote controls, telephones, light switches and faucets were contaminated with rhinovirus," said Hendley.

To begin the study, people with colds were recruited to spend 5 hours awake in hotel rooms before going to bed and 2 awake hours in their rooms the next morning. The volunteers had no visitors and were asked to wash their hands only after using the bathroom. At the time of check out, participants were asked to identify objects they had touched. After they left, ten of the touched objects in the subject's room were tested for the presence of rhinovirus. Thirty five percent of the objects had residual virus, demonstrating that people with colds do not have to be present for their germs to linger.

In order to infect an individual, germs must reach the eyes or the nose, usually by way of a person's own fingers. So researchers then set out to learn if germs lingering in the environment can make the leap from surfaces to fingers.In order to test this leap, researchers invited six of the participants to return to the hotel several months later. This time, virus-containing mucus taken at the time of the participants' colds, which had been stored, was used to contaminate two sets of light switches, telephone key pads and telephone handsets in two different rooms. In one room, the mucus was allowed to dry for one hour. In the second room, the mucus dried overnight. The participants were asked to dial phone numbers, hold the handsets and flip on light switches in both rooms. Sixty percent of the contacts with contaminated objects that dried for an hour resulted in rhinovirus transfer to fingertips. Thirty-three percent of contacts with objects that dried overnight resulted in rhinovirus transfer to fingertips.

Reverse transcription-polymerase chain reaction was used to detect rhinovirus ribonucleic acid (RNA). The RNA of rhinovirus is surrounded by proteins that help it bind to other cells. Without a host cell, the virus cannot replicate, making it even more surprising that it survived overnight to be detected and transferred. "While transmission of rhinovirus through dried nasal mucus on surfaces is not efficient, people still should understand that the virus remains available for transfer at least one day," said Hendley. "The next time you stay in a hotel, knowing that rhinovirus may be left from the last guest, you may wonder how meticulous the clean up crew was in their work."

Rhinovirus

Host Defence
Take a look at the funny video that i have put up to for further understanding on this virus.



Rhinovirus transmitted by aerosol or direct contact. The primary site of inoculation is the nasal and conjunctiva may be involved to a lesser extent. Rhinovirus attaches to respiratory epithelium and spreads locally.





The natural response of the human defense system to injury involves ICAM-1, which aids the binding between endothelial cells and leukocytes. Rhinovirus takes advantage of the ICAM-1 by using it as a receptor for attachment. In addition, Rhinovirus uses ICAM-1 for subsequent viral uncoating during cell invasion. Some Rhinovirus serotypes also up-regulate ICAM-1 expression on human epithelial cells to increase susceptibility to infection.



The optimal temperature for Rhinovirus replication is 33-35°C. Rhinovirus does not efficiently replicate at body temperature. This may explain why Rhinovirus replicates well in the nasal passages and upper tracheobronchial tree but less well in the lower respiratory tract. The incubation period is approximately 2-3 days. Viremia is uncommon.



Rhinovirus is shed in large amounts, with as many as 1 million infectious virions present per mL of nasal washings. Viral shedding can occur a few days before cold symptoms are recognized by the patient, peaks on days 2-7 of the illness, and may last as long as 3-4 weeks.



A local inflammatory response to the virus in the respiratory tract can lead to nasal discharge, nasal congestion, sneezing, and throat irritation. Damage to the nasal epithelium does not occur, and inflammation is mediated by the production of cytokines and other mediators.



Histamine concentrations in nasal secretions do not increase. By days 3-5 of the illness, nasal discharge can become mucopurulent from polymorphonuclear leukocytes that have migrated to the infection site in response to chemoattractants. Nasal mucociliary transport is markedly reduced during the illness and may be impaired for weeks. Both secretory immunoglobulin A and serum antibodies are involved in resolving the illness and protecting from reinfection.



Coronaviruses, reinfections with parainfluenza, and respiratory syncytial virus (RSV) are the most important of many other viruses that can cause common colds. Other viruses can also cause common colds but are more likely to cause acute nasopharyngitis and more severe respiratory infections.



Mycoplasma pneumoniae can occasionally present with common cold symptoms before developing into more extensive respiratory disease. Abnormalities on CT scan findings (mucosal thickening) are present in adults with common colds that resolve over 1-2 weeks without antibiotic therapy.

Rhinovirus

Rhinovirus

Viral disease

Colds are caused by more than two hundred different viruses. The most common groups of viruses are rhinoviruses and coronaviruses.

The virus can be passed in various ways. When an infected person coughs, sneezes, or speaks, for example, fluid droplets containing the virus are discharged. People nearby may breathe in the droplets and may then become infected.

Cold viruses can be passed from person to person through direct contact, such as shaking hands. The viruses can also be spread through nonliving objects, such as doorknobs, telephones, and toys. This method of transmission is common in day-care centers. A child with a cold may transfer the cold virus to a toy with which he or she is playing. When another child picks up the same toy, he or she may also pick up the cold virus.

Most colds are caused by rhinoviruses that are in invisible droplets in the air we breathe or on things we touch. More than 100 different rhinoviruses can infiltrate the protective lining of the nose and throat, triggering an immune system reaction that can cause a throat sore and headache, and make it hard to breathe through the nose.

Air that's dry — indoors or out — can lower resistance to infection by the viruses that cause colds. And so can being a smoker or being around someone who's smoking. People who smoke are more likely to catch a cold than people who don't — and their symptoms will probably be worse, last longer, and are more likely to lead to bronchitis or even pneumonia.

Rhinovirus

Rhinovirus

Viral structure & Classification

Rhinoviruses contain a single stranded RNA genome within an icosahedral capsid between 7.2 and 8.5kb in length. They are small (30 nm) non-enveloped viruses. At the 5′ end of the genome is a virus-encoded protein, and like mammalian mRNA, there is a 3′ tail. Structural proteins are encoded in the 5′ region of the genome and non structural at the end.

Rhinoviruses belong to the Picornaviridae family, which includes the genera Enterovirus and Hepatovirus. Approximately 101 serotypes have been identified.

Introduction

Welcome to our blog!
The author of this blogs are the DASS...

• Diana
• Atiqah
• Syafeeqah
• Syukri

In our blog, the topic that we will be sharing with you is Virology which is the study of viruses. This would include:

• the structure of viruses and its classification
• Viral disease and host defence
• Molecular biology research and viral therapy
• Other uses of viruses

And so feel free to leave us your comments and suggestions!