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Biotech / Medical : GUMM - Eliminate the Common Cold -- Ignore unavailable to you. Want to Upgrade?


To: Bo Didley who wrote (5155)10/16/2004 4:08:37 PM
From: Frank_Ching  Respond to of 5582
 
The Linus Pauling Institute. Intranasal zinc (zinc nasal gels and nasal sprays)

lpi.oregonstate.edu

Intranasal zinc (zinc nasal gels and nasal sprays)

Intranasal zinc preparations designed to be applied directly to the nasal epithelium (cells lining the nasal passages) are also marketed as over-the-counter cold remedies. While two placebo-controlled trials found that intranasal zinc gluconate modestly shortened the duration of cold symptoms (35, 36), two other placebo-controlled studies found intranasal zinc to be of no benefit (37, 38). In the most rigorously controlled of these studies, intranasal zinc gluconate did not affect the severity or duration of cold symptoms in volunteers inoculated with rhinovirus, a common cause of colds (37). Of concern are several case reports of individuals experiencing loss of the sense of smell (anosmia) after using intranasal zinc as a cold remedy (39,40). Since zinc-associated anosmia may be irreversible, intranasal zinc preparations should be avoided.

Last updated 12/16/2003 Copyright 2001-2003 The Linus Pauling Institute

--------------------------------------------------------------------------------

Disclaimer

The Linus Pauling Institute Micronutrient Information Center provides scientific information on health aspects of micronutrients and phytochemicals for the general public. The information is made available with the understanding that the author and publisher are not providing medical, psychological, or nutritional counseling services on this site. The information should not be used in place of a consultation with a competent health care or nutrition professional.

The information on micronutrients and phytochemicals contained on this Web site does not cover all possible uses, actions, precautions, side effects, and interactions. It is not intended as medical advice for individual problems. Liability for individual actions or omissions based upon the contents of this site is expressly disclaimed.




To: Bo Didley who wrote (5155)10/23/2004 1:29:44 PM
From: Frank_Ching  Respond to of 5582
 
Merck: "Colds caused by rhinoviruses occur more commonly in the spring and fall; different viruses cause colds during other times of the year."

"Other

Zinc (lozenges or nasal gel) Metallic taste"

merck.com

Common Cold


The common cold is a viral infection of the lining of the nose, sinuses, throat, and large airways.

Common colds are among the most common illnesses. Many different viruses cause colds, but the rhinoviruses (of which there are 100 subtypes) are implicated more often than others. Colds caused by rhinoviruses occur more commonly in the spring and fall; different viruses cause colds during other times of the year.

Colds mainly spread when a person's hands come in contact with nasal secretions from an infected person. These secretions contain cold viruses. When the person touches his mouth, nose, or eyes, the viruses gain entry to the body and produce a new cold. Less often, colds are spread when a person breathes air that contains droplets that were coughed or sneezed out by an infected person. A cold is most contagious in the first 1 or 2 days after symptoms develop. Becoming chilled does not cause colds, nor does it increase a person's susceptibility to infection. A person's general health and eating habits also do not seem to affect susceptibility to infection, nor does having an abnormality of the nose or throat (such as enlarged tonsils or adenoids).

Symptoms and Diagnosis

Symptoms of the cold start 1 to 3 days after infection. Usually, the first symptom is discomfort in the nose or throat. Later, the person starts sneezing, has a runny nose, and feels mildly ill. Fever is not common, but a mild fever may develop at the beginning of the illness. At first, the secretions from the nose are watery and clear and can be annoyingly plentiful; eventually they become thicker, opaque, yellow-green, and less abundant. Many people also develop a cough. Symptoms usually disappear in 4 to 10 days, although a cough often lasts into the second week.

Complications may prolong the illness. Rhinovirus infection often triggers asthma attacks in people with asthma. Some people develop bacterial infections of the middle ear (otitis media) or sinuses because of a cold. These infections develop because congestion in the nose blocks the normal drainage of those areas, allowing bacteria to grow in collections of blocked secretions. Other people develop bacterial infections of the lower airways (secondary bronchitis or pneumonia).

Doctors are usually able to diagnose a cold from the typical symptoms. A high fever, severe headache, rash, difficulty breathing, or chest pain suggests that the infection is not a simple cold. Laboratory tests usually are not needed to diagnose a cold. If complications are suspected, doctors may order blood tests and x-rays.

Prevention

Because so many different viruses cause colds and because each virus changes slightly over time, an effective vaccine has not yet been developed. The best preventive measure is practicing good hygiene. Because many cold viruses are spread through contact with the secretions of an infected person, both the sick person and the people in his household and office should wash their hands frequently. Sneezing and coughing should be done into tissues, which should then be carefully disposed of. When possible, the sick person should sleep in a separate room. People who are coughing or sneezing from a cold should not go to work or school where they might infect others. Cleaning shared objects and surfaces can also help to reduce the spread of common cold viruses.

Despite their popularity, echinacea and high-dose vitamin C (up to 2,000 milligrams per day) have not been shown to prevent colds. When sprayed into the nose, the substance interferon reduces the chance of acquiring a rhinovirus cold. However, interferon causes irritation and bleeding of the nose and does not work against other cold viruses. Interferon nasal spray is not commercially available in the United States.

Treatment

A person with a cold should stay warm and comfortable and try to avoid spreading the infection to others. Anyone with a fever or severe symptoms should rest at home. Drinking fluids and inhaling steam or mist from a vaporizer may help to keep secretions loose and easier to expel.

Currently available antiviral drugs are not effective against colds. An experimental antiviral drug called pleconarilSome Trade Names
PICOVIR
reduces the duration and severity of cold symptoms and may become available in the near future. Antibiotics do not help people with colds, even when the nose or cough produces colored mucus.

Echinacea (see Medicinal Herbs and Nutraceuticals: Echinacea), zinc preparations, and vitamin C have been suggested as therapy for colds. Small studies have shown them to be effective, but the effectiveness has not been confirmed in rigorous, large clinical studies.

Several popular nonprescription remedies that help the symptoms of a cold are available (see Over-the-Counter Drugs: Cold Remedies). Because they do not cure the infection, which usually resolves after a week anyway, doctors feel that their use is optional, depending on how bad the person feels. Several different types of drugs are used to relieve cold symptoms: decongestants help open clogged nasal passages, antihistamines help dry a runny nose, and cough syrups make coughing easier by thinning secretions or suppressing cough. These drugs are most often sold as combinations but can also be obtained individually. Antihistamines can cause drowsiness and are particularly problematic in older people.

AspirinSome Trade Names
ECOTRIN
ASPERGUM
is generally not recommended for children because in that age group it is associated with an increased risk of Reye's syndrome. Cough suppressants are not routinely recommended because coughing is a good way to clear secretions and debris from the airways during a viral infection. However, a severe cough that interferes with sleep or causes great discomfort can be treated with a cough suppressant.




Nonprescription Cold Remedies



Type
Drug
Side Effects


Analgesics/Antipyretics (relieve aches and pains, reduce fever)


Acetaminophen Minimal

Aspirin Reye's syndrome possible in children with influenza, stomach irritation

Nonsteroidal anti- inflammatory drugs such as ibuprofen and naproxen Stomach irritation

Antihistamines (open nasal passages, help relieve sneezing)


Brompheniramine
Chlorpheniramine
Clemastine
Diphenhydramine
All can cause drowsiness, dry mouth, blurred vision, difficulty urinating, constipation, and, in older people, light-headedness on standing and confusion

Cough suppressants (reduce cough)


Benzonatate Confusion, stomach upset

Codeine Constipation, drowsiness, difficulty urinating, stomach upset

Dextromethorphan Minimal; confusion, nervousness and irritability at high doses

Decongestants (nasal spray) (open clogged nasal passages)


Naphazoline
Oxymetazoline
Phenylephrine
Xylometazoline
Rebound congestion (worse congestion when drug wears off)

Decongestant (oral) (dries runny nose)


Pseudoephedrine Palpitations, high blood pressure, nervousness, insomnia

Expectorant (loosens mucus)


Guaifenesin Minimal, headache and stomach upset at high doses

Other


Zinc (lozenges or nasal gel) Metallic taste










To: Bo Didley who wrote (5155)10/23/2004 1:59:57 PM
From: Frank_Ching  Respond to of 5582
 
Common Cold Caused By Multiple Viruses, New Study Reveals
sciencedaily.com

February 2, 1998--A recent study investigating causes of the common cold affirms that most colds are caused by viruses, but only half are a result of infection with the rhinovirus, the virus most often implicated in colds. These findings support the recommendations that antibiotics, which do not work on viral infections, not be used to treat cold symptoms. The study appears in the February 1998 issue of the Journal of Clinical Microbiology.

Researchers from the National Public Health Institute of Finland report on a study of 200 cases of the common cold in university students over a one-year period. Student participants were asked to identify when they had a cold, based on a set of symptoms, and contact a study office, set up at the university, within two days of the appearance of the symptoms. The students were then tested to determine the cause of the symptoms.

In 138 of the 200 cases, the researchers were able to identify an infectious agent as the cause. Rhinovirus was found to be the cause of 105, or just over half the cases in the study. Other causes of cold symptoms included coronavirus, influenza A virus, and respiratory syncitial virus (RSV). All of these viruses are known to cause symptoms associated with colds. Nearly all the colds with a known cause were found to be caused by a viral infection. Only 7 patients were found to have bacterial infections, but six were also found to have a viral infection as well.

"These findings are consistent with our recommendations that antibiotics not be used to treat common cold symptoms" says Stuart Levy, president-elect of the American Society for Microbiology. "Almost all cases of the common cold are caused by viruses and antibiotics do not work on viral infections. The unnecessary and inappropriate use of antibiotics to treat cold symptoms is contributing to the development of antibiotic-resistant bacteria.

Despite this research and previous studies showing that antibiotics are of little use in treating the common cold, it is estimated that up to 60% of patients with common colds receive some type of antibiotic. This results in an estimated cost of $37.5 million per year in the United States for unnecessary prescriptions on top of the risk of developing antibiotic resistance.

Mild upper respiratory illness, also known as the common cold, is identified by a set of symptoms. These symptoms can include inflamed sinuses, nasal congestion and a sore throat. Studies done as early as the 1960s have identified rhinovirus as a frequent cause of colds, but the number of cases in which rhinovirus was detected has been as low as 25 percent. Although diagnostic methods have improved greatly since then, no studies into the cause of the common cold have been published recently.

The researchers say that individuals who develop colds do not need to have their doctors test for the cause. The price of diagnosis ($700 per patient in this study) is too high and only in rare cases will it affect treatment.

The Journal of Clinical Microbiology is a publication of the American Society for Microbiology (ASM). With over 40,000 members worldwide, the ASM is the oldest and largest single biological membership organization in the world.

--------------------------------------------------------------------------------

This story has been adapted from a news release issued by American Society For Microbiology.



To: Bo Didley who wrote (5155)10/23/2004 2:09:55 PM
From: Frank_Ching  Respond to of 5582
 
Frequency: In the US: Common colds most frequently occur from September to April in temperate climates. RV infections, which are present throughout the year, account for the initial increase in cold incidence during the fall and a second incidence peak at the end of the spring season. Colds occurring from October through March are caused by the successive appearance of numerous viruses, including parainfluenza, coronavirus, RSV, and influenza virus. Adenoviral infections occur at a constant rate throughout the season.

emedicine.com

Rhinovirus Infection

Last Updated: August 31, 2004 Rate this Article
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Synonyms and related keywords: RV infection, common cold, upper respiratory infection, URI

AUTHOR INFORMATION Section 1 of 9
Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Bibliography



Author: Mai Ngoc Nguyen, MD, Staff Physician, Department of Pediatrics, Mattel Children's Hospital, University of California at Los Angeles
Coauthor(s): James D Korb, MD, Program Director, Department of Pediatrics, Children's Hospital of Orange County


Mai Ngoc Nguyen, MD, is a member of the following medical societies: American Academy of Pediatrics, and American Medical Association

Editor(s): José Rafael Romero, MD, Director of Pediatric Infectious Diseases Fellowship Program, Associate Professor, Department of Pediatrics, Combined Division of Pediatric Infectious Diseases, Creighton University/University of Nebraska Medical Center; Robert Konop, PharmD, Clinical Assistant Professor, Department of Pharmacy, Section of Clinical Pharmacology, University of Minnesota; Larry I Lutwick, MD, Director, Division of Infectious Diseases, Veterans Affairs New York Harbor Health Care System, Professor, Department of Internal Medicine, State University of New York at Downstate; Robert W Tolan, Jr, MD, Chief of Pediatric Infectious Diseases, St. Peter's University Hospital and Capital Health System, Clinical Associate Professor of Pediatrics, Drexel University College of Medicine; and Russell Steele, MD, Professor and Vice Chairman, Department of Pediatrics, Head, Division of Infectious Diseases, Louisiana State University Health Sciences Center
INTRODUCTION Section 2 of 9
Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Bibliography



Background: Rhinoviruses (RVs) are small (30 nm), nonenveloped viruses that contain a single-strand ribonucleic acid (RNA) genome within an icosahedral (20-sided) capsid. RVs belong to the Picornaviridae family, which includes the genera Enterovirus (polioviruses, coxsackieviruses groups A and B, echoviruses, numbered enteroviruses) and Hepatovirus (hepatitis A virus). Approximately 101 serotypes are identified currently.

This review focuses on the common cold because it most frequently is associated with RV. Nasopharyngitis, croup, and pneumonia, which uncommonly are caused by RV, also are discussed briefly. RV plays a significant role in the pathogenesis of otitis media and asthma exacerbations. Although incidence and prevalence are high, most cases are mild and self-limited.

Pathophysiology: RV can be transmitted by aerosol or direct contact. Primary site of inoculation is the nasal mucosa, although the conjunctiva may be involved to a lesser extent. RV attaches to respiratory epithelium and spreads locally. The major human RV receptor is intercellular adhesion molecule-1 (ICAM-1). The natural response of the human defense system to injury involves ICAM-1, which aids the binding between endothelial cells and leukocytes. RV takes advantage of the ICAM-1 by using it as a receptor for attachment. In addition, RV uses ICAM-1 for subsequent viral uncoating during cell invasion. Some RV serotypes also up-regulate the ICAM-1 expression on human epithelial cells to increase infection susceptibility.

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

RV is shed in large amounts, with as many as 1 million infectious virions per milliliter 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 for as many 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 such as interleukin-8. Nasal mucociliary transport is reduced markedly 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 (eg, adenoviruses, influenza viruses) also can cause common colds but are more likely to cause acute nasopharyngitis and more severe respiratory infections.

Mycoplasma pneumoniae occasionally can present with common cold symptoms before developing into more extensive respiratory disease. Other pathogens include Coccidioides immitis, Histoplasma capsulatum, Bordetella pertussis, Chlamydia psittaci, and Coxiella burnetii.

Recent clinical studies indicate sinus involvement in common colds. CT scan abnormalities (eg, opacification, air-fluid levels, mucosal thickening) are present in adults with common colds that resolve over 1-2 weeks without antibiotic therapy.

Folklore to the contrary, no good clinical evidence reports that colds are acquired by exposure to cold weather, getting wet, or becoming chilled.

Frequency:

In the US: Common colds most frequently occur from September to April in temperate climates. RV infections, which are present throughout the year, account for the initial increase in cold incidence during the fall and a second incidence peak at the end of the spring season. Colds occurring from October through March are caused by the successive appearance of numerous viruses, including parainfluenza, coronavirus, RSV, and influenza virus. Adenoviral infections occur at a constant rate throughout the season.
Numerous studies demonstrate common cold incidence to be highest in preschool and elementary school-aged children. An average of 3-8 colds per year is observed in this age group, with an even higher incidence for children attending day care and preschool. Given the numerous viral agents involved and the many serotypes of several viruses (especially RV), younger children having new colds each month during the winter season is not unusual. Adults and adolescents typically have 2-4 colds per year.

Internationally: Seasonal increase in incidence during the winter months is observed worldwide.
Mortality/Morbidity: The most common manifestation of RV, the common cold, is mild and self-limited. However, rarely severe respiratory disease, including bronchiolitis and pneumonia, can occur in infants.

Race: American Indian and Eskimo people are more likely to develop the common cold and appear to have more frequent complications such as otitis media. These findings may be explained as much by environmental conditions (eg, poverty, overcrowding) as by ethnicity.

Age: Since antibodies to viral serotypes develop over time, highest incidence is found in infants and younger children. In addition, younger children are more likely to have the frequent, close, personal contact necessary to transmit RV. Contrary to the experience of adults, children also may be more contagious due to having higher virus concentrations in secretions and longer duration of viral shedding. CLINICAL Section 3 of 9
Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Bibliography



History: RV directly can cause or indirectly can predispose to a variety of upper respiratory tract infections (URTI) and lower respiratory tract infections (LRTI), which are less common.

Common cold
Nose dryness or irritation often is the first symptom and is followed within hours by profuse watery rhinorrhea, nasal congestion, and sneezing.

A sore throat or throat irritation is common.
Malaise, headache, and cough also are common symptoms of the common cold.

Fever is absent or low grade. Infants and preschoolers are more likely to experience fevers, which are often 38-39°C.
Nasal secretions typically become thicker and colored after the first few days of illness.

Irritability or restlessness is common.
Nasal obstruction can interfere with sleep and feeding.

Posttussive vomiting can occur.

Symptoms in adults and adolescents usually resolve by day 7; however, symptoms often last 10-14 days in younger children.
Acute otitis media
Viral URIs are common precipitating factors for acute otitis media (AOM), probably by causing respiratory mucosal inflammation, leading to eustachian tube obstruction.

Respiratory viruses are found in either the middle ear fluid or nasopharynx in approximately 40% of patients with AOM.
As many as 24% of patients with AOM have RV present in nasopharyngeal secretions. RV also has been obtained from middle ear fluid.

Patients whose symptoms are refractory to treatment with antibiotics are more likely to have positive viral cultures from the middle ear.
Sinusitis
Viral respiratory infections commonly cause more frequent and more severe asthma exacerbations in individuals of all ages.

Preceding RV infection can lead to bacterial superinfection.
Asthma exacerbations
Viral URI is the most common trigger for asthma exacerbations in children of all ages.

For children younger than 5 years, RV and RSV are the most commonly implicated pathogens. RV is the most commonly implicated pathogen for older children.
LRTI: RV may cause both pneumonia and bronchiolitis in infants.
Croup: RV may cause laryngotracheobronchitis in infants.
Acute nasopharyngitis
The patient's physical examination reveals nasal discharge and a sore throat, including throat inflammation (eg, erythema, exudate, ulcers). Fever is common and can be high.

Acute nasopharyngitis most commonly is caused by adenovirus, enteroviruses, influenza, and parainfluenza.

RV is an uncommon cause of acute nasopharyngitis.

Common colds, by definition, do not have objective evidence of pharyngeal irritation.
Cystic fibrosis: RV is the implicated virus in as many as 57% of respiratory exacerbations.
Transmission modes
RV possesses a variety of transmission modes and can infect a huge population at any given time.

Aerosol transmission is the most common transmission mode for respiratory tract infections (RTIs). Transmission occurs when small airborne particles are inhaled or large droplets are touched directly.

Direct hand contact with infected secretions or indirect contact with fomites that contain secretions also is important. Patients then infect themselves by touching their noses or conjunctivae.

Highly contagious behavior includes nose blowing, sneezing, and physically transferring infected secretions onto environmental surfaces or paper tissue.
Contrary to popular belief, behaviors such as kissing, talking, coughing, or even drooling do not contribute highly to the spread of disease.

Infection rates approximate 50% within the family household and range from zero to 50% within schools, which indicates that transmission requires long-term contacts with infected individuals. Brief exposures to others in places such as the movies, shopping malls, friends' houses, or doctors' offices present low risks of infection transmission.

Incubation period is approximately 2-4 days.

Because children carry the fewest antibodies, children attending school are the most common reservoirs of RV infection.
Physical:

Common cold
The common cold usually is afebrile, although temperatures of 38-39°C are possible in younger children.
Profuse nasal discharge can be clear and watery or mucopurulent. Purulent secretions are common after the first few days of illness and do not imply bacterial sinusitis unless secretions persist for more than 10-14 days.
Edema and erythema of nasal mucosa occur.
Despite the sore throat symptom, the pharynx has a normal appearance, without any erythema, exudate, or ulceration.
Mildly enlarged nontender cervical lymph nodes are present.
Causes:

Factors that increase infection risk and severity
Smoking increases risk of respiratory infection by approximately 50%.
Very young or old individuals are at greater risk, possibly because of decreased immunity.
Exposure to infected contacts increases infection risk.
Touching the conjunctiva or nose with contaminated fingers and/or objects increases infection risk.
Crowding leads to increased transmission.
Men may have a slightly, probably insignificant, higher risk.
Feeding on breast milk has little, if any, effect on the incidence of common colds.
Underlying chronic medical conditions, including anatomic, metabolic, genetic, or immunologic disorders (ie, tracheoesophageal fistulas, congenital heart disease, cystic fibrosis, immunodeficiencies) increase infection risk and severity.
DIFFERENTIALS Section 4 of 9
Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Bibliography



Allergic Rhinitis
Bronchiolitis
Bronchitis, Acute and Chronic
Pertussis
Pneumonia
Sinusitis

Other Problems to be Considered:

Acute nasopharyngitis

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Allergic Rhinitis

Bronchiolitis

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Pertussis

Pneumonia

Sinusitis



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WORKUP Section 5 of 9
Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Bibliography



Lab Studies:

Diagnostic studies generally are unnecessary for patients with the common cold.
Clinical signs and symptoms of the common cold, by definition, are similar regardless of the infectious etiology.
In addition, with approximately 100 different serotypes of RV alone, assisting the diagnosis by serologic methods is economically impractical.
WBC has little value in the workup of the common cold.
If a specific viral diagnosis is desired, the virus can be cultured from nasal secretions.
Nasal washings are more sensitive than throat specimens.
Direct antigen tests are routinely available for influenza and RSV. Some centers offer direct antigen tests for parainfluenza and adenovirus.
Imaging Studies:

Routine use of imaging studies is unnecessary.
More than 85% of patients with the common cold have sinus abnormalities on CT scan. Do not make a bacterial sinusitis diagnosis if symptom duration is fewer than 10-14 days.
TREATMENT Section 6 of 9
Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Bibliography



Medical Care:

The following treatment options are still experimental and not proven:
Developing a vaccine: Development of a vaccine is nearly impossible because of the numerous serotypes. No antiviral agents for treating infections exist.

Accelerating nasal drainage: Hot chicken soup causes a temperature increase that accelerates nasal drainage. Be aware of possible hypernatremia.

Providing inhaled, warm, humidified air: Nasal hyperthermia is based on the fact that increased temperatures inhibit RV replication in vitro. Inhaled, warm, humidified air (40 L/min at 40-44ºC in nostrils) has produced inconsistent findings among several studies.

Using aroma rubs, homeopathic and/or herbal remedies, and ultrafine high-volume filtration systems: These treatment options have yet to be studied.

Using experimental drugs: Many experimental drugs currently are in trials or have not been approved for consumer use. These include capsid-binding agents, pirodavir, WIN 54954, intranasal interferon (IF), virus receptor blockers, antireceptor antibodies, and soluble ICAM-1.
Most treatment provides supportive measures for respiratory illness symptoms. Conventional treatments for the common cold include the following:
Obtaining phenol-alcohol environment and solution (Lysol) to disinfect the environment

Washing hands

Obtaining rest, plenty of fluids, and reassurance that the usual viral course is 6-10 days
Positioning mattress at a 45° angle

Providing comfortable surrounding temperature and adequate humidity: This treatment method soothes irritated nasopharyngeal mucosa and helps eliminate nasal secretions by preventing dryness.

Using decongestants: Decongestants and antihistamines are not recommended for children younger than 6 months.
Using nasal saline drops with bulb syringe nostril aspiration: This treatment can help infants with congestion and obstruction.

Discontinuing smoking or using alcohol
Consultations: Refer to an allergist if patient has chronic rhinitis unresponsive to environmental and pharmacologic intervention.
MEDICATION Section 7 of 9
Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Bibliography



Symptomatic treatment with analgesics, decongestants, antihistamines, and antitussives is currently the mainstay of therapy. Some clinicians advocate supplementation with vitamin C; however, high doses in children are not recommended. Zinc lozenges are not practical because of the metallic taste. The investigational agent pleconaril may be approved soon. Pleconaril is a capsid-binding isoxazole drug that induces conformational changes after binding to the RV shell, leading to altered receptor attachment. It inhibits viral uncoating, thus inhibiting replication.
Other drugs that are currently experimental or not approved for rhinovirus include the following:

Interferon alpha: Most effective for cold prevention, interferon alpha is ineffective for established colds. When administered through nasal spray, 80% of secondary RV colds were prevented. Interferon alpha is not cost-effective. Significant adverse effects exist.

Pirodavir: A substituted phenoxy-pyridazinamine, pirodavir possesses broad antipicornavirus activity. Clinical studies demonstrate no decrease in viral shedding or symptoms.

WIN 54954: A methylisoxazole derivative, WIN 54954 has no significant antiviral or clinical effects.

Virus receptor blockers: These drugs are hypothesized to block virus internalization to prevent replication.

Antireceptor antibody: Tests demonstrate no decrease in infection frequency.

Soluble ICAM-1: This drug consists of a molecule that blocks replication by binding receptor sites and inhibiting viral attachment and internalization. Currently, no clinical trials exist.

Drug Category: Analgesic and antipyretic agents -- For relief of pain, discomfort, or fever. Inhibits central synthesis and release of prostaglandins that mediate effect of endogenous pyrogens in hypothalamus; thus, promotes return of set-point temperature to normal. Ibuprofen also possesses anti-inflammatory properties.Drug Name
Ibuprofen (Motrin, Advil) -- One of few NSAIDs indicated for reduction of fever.
Adult Dose 200-400 mg PO q4-6h while symptoms persist, not to exceed 3.2 g/d
Pediatric Dose 5-10 mg/kg/dose PO q6-8h, not to exceed 40 mg/kg/d
Contraindications Documented hypersensitivity; aspirin; active GI bleeding and ulcer disease
Interactions Coadministration with aspirin increases risk of inducing serious NSAID-related adverse effects; probenecid may increase concentrations and, possibly, toxicity of NSAIDs; may decrease effect of hydralazine, captopril, and beta-blockers; may decrease diuretic effects of furosemide and thiazides; may increase PT when taking anticoagulants (instruct patients to watch for signs of bleeding); may increase risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently
Pregnancy C - Safety for use during pregnancy has not been established.
Precautions Category D in third trimester of pregnancy; caution in congestive heart failure, hypertension, and decreased renal and hepatic function; caution in anticoagulation abnormalities or during anticoagulant therapy; caution in infants and young children; do not use in neonates secondary to CNS effects
Drug Name
Acetaminophen (Tylenol, Feverall, Tempra) -- Reduces fever by acting directly on hypothalamic heat-regulating centers, which increases dissipation of body heat via vasodilation and sweating.
Adult Dose 325-650 mg PO q4-6h or 1000 mg tid/qid, not to exceed 4 g/d
Pediatric Dose 10-15 mg/kg/dose PO/PR q4-6h, not to exceed 4 g/d
Contraindications Documented hypersensitivity; known G-6-PD deficiency
Interactions Rifampin can reduce acetaminophen analgesic effects; coadministration with barbiturates, carbamazepine, hydantoins, and isoniazid may increase hepatotoxicity
Pregnancy B - Usually safe but benefits must outweigh the risks.
Precautions Contained in many OTC products, and combined use with these products may result in cumulative doses exceeding recommended maximum dose; caution parents regarding varying concentrations of OTC products
Drug Category: Antihistamines -- Relieve runny nose, watery eyes, or other allergiclike symptoms. Act by competitive inhibition of histamine at H1 receptor. This mediates wheal and flare reactions, bronchial constriction, mucous secretions, smooth muscle contraction, edema, hypotension, CNS depression, and cardiac arrhythmias.Drug Name
Brompheniramine (Dimetapp, Dimetane) -- Alkylamine antihistamine primarily used for treating allergic symptoms.
Adult Dose Regular release: 4 mg PO q4-6h
SR: 8 mg PO q8-12h; 12 mg PO q12h
Pediatric Dose <6 years: 0.5 mg/kg/d PO divided q6-8h, not to exceed 6-8 mg/d
6-12 years: 2-4 mg/dose PO q6-8h, not to exceed 12-16 mg/d
>12 years: Administer as in adults
Contraindications Documented hypersensitivity; narrow-angle glaucoma; bladder neck obstruction; concurrent use of MAOIs
Interactions Potentiates effect of CNS depressants; MAOIs, sympathomimetics; propranolol
Pregnancy B - Usually safe but benefits must outweigh the risks.
Precautions High blood pressure; heart disease; diabetes; thyroid disease; asthma; glaucoma
Drug Category: Decongestants -- Relieve congestion of nasal passages or sinuses.Drug Name
Pseudoephedrine (Sudafed) -- Stimulates vasoconstriction by directly activating alpha-adrenergic receptors of respiratory mucosa. Also induces bronchial relaxation and increases heart rate and contractility by stimulating beta-adrenergic receptors.
Adult Dose 60 mg q4-6h or 120 mg SR q12h, not to exceed 240 mg/d
Pediatric Dose 6-12 years: 4 mg/kg/d PO divided q6h
>12 years: 30-60 mg/dose PO q6-8h, not to exceed 240 mg/d
Contraindications Documented hypersensitivity; severe anemia; postural hypertension or hypotension; closed-angle glaucoma; head trauma; cerebral hemorrhage
Interactions Propranolol, MAOIs, and sympathomimetic agents may increase toxicity; methyldopa and reserpine may reduce effects
Pregnancy B - Usually safe but benefits must outweigh the risks.
Precautions Hyperthyroidism; diabetes mellitus; prostatic hypertrophy; mild-to-moderate hypertension; arrhythmia; hyperglycemia
Drug Name
Phenylephrine nasal (Neo-Synephrine) -- Strong postsynaptic alpha-receptor stimulant with little beta-adrenergic activity; produces vasoconstriction of arterioles, which decreases congestion.
Adult Dose 2-3 gtt or 1-2 sprays intranasally of 0.5% solution q4h
Pediatric Dose 6-12 months: 1-2 gtt intranasally of 0.16% solution q3h prn
1-6 years: 2-3 gtt intranasally of 0.125% solution q4h prn
6-12 years: 2-3 gtt intranasally or 1-2 sprays of 0.25% solution q4h prn
>12 years: 2-3 gtt intranasally or 1-2 sprays of 0.5% solution q4h
Contraindications Documented hypersensitivity; pheochromocytoma and severe hypertension; acute pancreatitis; hepatitis; myocardial disease; severe coronary disease; peripheral or mesenteric vascular thrombosis
Interactions Bretylium may potentiate action of vasopressors on adrenergic receptors, possibly resulting in arrhythmias; MAOIs significantly may enhance adrenergic effects, and pressor response may be increased 2- to 3-fold; guanethidine may increase pressor response of direct-acting vasopressors, possibly resulting in severe hypertension
Pregnancy C - Safety for use during pregnancy has not been established.
Precautions Arrhythmia; hyperthyroidism; hyperglycemia
Drug Category: Antitussive agents -- Act either centrally or peripherally on cough reflex or combination of both. Central acting agents increase threshold of cough center in brain to incoming stimuli, whereas those acting peripherally decrease sensitivity of receptors in respiratory tract.Drug Name
Dextromethorphan (Robitussin, Delsym) -- Antitussive and/or expectorant that comes as single entity or in variety of cough and cold preparations in various combinations.
Adult Dose Regular release: 10-30 mg PO q4-8h, not to exceed 120 mg/d
SR: 60 mg PO bid
Pediatric Dose 1-3 months: 0.5-1 mg PO q6-8h
3-6 months: 1-2 mg PO q6-8h
7 months to 1 year: 2-4 mg PO q6-8h
2-6 years: 2.5-7.5 mg PO q4-8h, not to exceed 30 mg/d
6-12 years: 5-10 mg PO q4-6h, not to exceed 60 mg/d
>12 years: Administer as in adults
Contraindications Documented hypersensitivity
Interactions May decrease hypotensive effects of guanethidine; MAOIs significantly may enhance adrenergic effects
Pregnancy C - Safety for use during pregnancy has not been established.
Precautions High blood pressure or tachycardia; thyroid disorders; diabetes mellitus
Drug Name
Codeine -- For symptomatic relief of cough. Helpful for pain of intercostal muscle strain associated with cough. Binds to opiate receptors in CNS, causing inhibition of ascending pain pathways, altering perception and response to pain.
Adult Dose 10-20 mg/dose PO q4-6h prn for cough, not to exceed 120 mg/d
Pediatric Dose 1-1.5 mg/kg/d PO divided q4-6h prn
Contraindications Documented hypersensitivity; children <2 y
Interactions CNS depressants; TCAs may potentiate codeine effects; phenothiazine may antagonize analgesic effect; dextromethorphan may enhance analgesic effect
Pregnancy D - Unsafe in pregnancy
Precautions Hypersensitivity reactions to other phenanthrene-derivative opioid agonists; respiratory diseases; severe liver and/or renal insufficiency
Drug Category: Antipicornaviral agents -- Experimental agents that may reduce duration and severity of respiratory symptoms.Drug Name
Pleconaril (Picovir) -- Capsid-binding isoxazole drug that induces conformational changes, leading to altered receptor attachment. Also inhibits viral uncoating. May be licensed for use soon.
Adult Dose Experimental dose: 200-400 mg PO tid pc
Pediatric Dose Experimental dose: 5 mg/kg/dose PO q8-12h pc
Contraindications Documented hypersensitivity
Interactions None reported
Pregnancy C - Safety for use during pregnancy has not been established.
Precautions Renal or hepatic dysfunction; pregnancy because data are lacking
Drug Category: Vitamin C -- May decrease severity and duration (large doses not recommended for children).Drug Name
Ascorbic acid (Vita-C) -- Effect on cold severity and duration is still controversial. Vitamin C comes in variety of formulations.
Adult Dose Dietary supplement: 50-200 mg/d PO
Prevention and treatment of cold: 1-3 g/d PO
Pediatric Dose Dietary supplement: 35-100 mg/d PO
Contraindications Documented hypersensitivity; pregnancy if large doses administered
Interactions Decreases effects of warfarin and fluphenazine; increases aspirin levels
Pregnancy A - Safe in pregnancy
Precautions Prolonged high doses may cause renal calculi, especially in patients with diabetes
FOLLOW-UP Section 8 of 9
Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Bibliography



Further Outpatient Care:

Advocate supportive measures such as rest, analgesics, and adequate hydration.
Instruct per Patient Education.
Deterrence/Prevention:

Avoid aspirin if a child has a viral illness because Reye syndrome complication is possible.
Prognosis:

Complete recovery usually is observed within 7 days for adolescents and adults and within 10-14 days for children. Occasionally, a child's cough and congestion linger for 2-3 weeks.

Patient Education:

Reassure family and patient that frequent colds are common at certain times of the year.
Advising parents that 6-12 colds per year can be normal for young children, especially if they are attending day care or preschool, is helpful.
Frequent self-limited colds do not indicate a problem with the child's immune system and do not require antibiotic treatment.
Because spread of secretions by contact with hands is a major route of transmission, encourage parents and patient to wash their hands frequently.
Advise patient to return to the clinic if fever exceeds 102°F, significant respiratory distress develops, or symptoms do not resolve in 10-14 days.
Advise patient that purulent nasal discharges commonly are observed after the first few days of the infection and do not indicate a bacterial infection or the need for antibiotics.
Patients with common colds do not need to be excluded from day care or preschool settings.
For excellent patient education resources, visit eMedicine's Cold and Flu Center. Also, see eMedicine's patient education article Colds.
BIBLIOGRAPHY Section 9 of 9
Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Bibliography



Arruda E, Hayden FG: Update on therapy of influenza and rhinovirus infections. In: Advances in Experimental Medicine and Biology. 1996; 394: 175-87.
Atmar RL, Dick EC, Byers RL: Rhinoviruses. In: Oski's Pediatrics, Principles and Practice, 3rd ed. 1999: 1084-1086, 1217, 1276-1280.
Bella J, Rossmann MG: Review: rhinoviruses and their ICAM receptors. J Struct Biol 1999 Dec 1; 128(1): 69-74[Medline].
Busse WW, Gern JE, Dick EC: The role of respiratory viruses in asthma. Ciba Foundation Symposium 1997; 206: 208-213.
Denny FW Jr: The clinical impact of human respiratory virus infections. Am J Respir Crit Care Med 1995 Oct; 152(4 Pt 2): S4-12[Medline].
Dershewitz RA, Macknin ML: The common cold. In: Ambulatory Pediatric Care, 3rd ed. 1999: 834-36.
Greve JM, Davis G, Meyer AM, et al: The major human rhinovirus receptor is ICAM-1. Cell 1989 Mar 10; 56(5): 839-47[Medline].
Monto AS: Viral respiratory infections in the community: epidemiology, agents, and interventions. Am J Med 1995 Dec 29; 99(6B): 24S-27S[Medline].
Peter G: Rhinovirus. In: 1997 Red Book: Report of the Committee on Infectious Diseases, 24th ed. 1997: 448.
Pitkaranta A, Hayden FG: Rhinoviruses: important respiratory pathogens. Ann Med 1998 Dec; 30(6): 529-37[Medline].
Romero JR: Pleconaril: a novel antipicornaviral drug. Expert Opin Investig Drugs 2001 Feb; 10(2): 369-79[Medline].
Siberry GK, Iannone R: The Harriet Lane Handbook, 15th ed. 2000.
Smith MB: Acute rhinitis and pharyngitis. In: Evidence-Based Pediatrics. 2000: 83-90.
Spiteri MA, Bianco A: The clinical and biological impact of viral respiratory infections on the human airway: focus on the rhinovirus. Monaldi Arch Chest Dis 1998 Feb; 53(1): 80-2[Medline].
Yamaya M, Sekizawa K: Rhinovirus infection of primary cultures of hum tracheal epithelium: role of ICAM-1 and IL-1 beta. Am J Physiology 1997; 273: L749-59.
Zambrano JC, Rakes GP: Virus-induced wheezing in children. Immunology and Allergy Clinics of North America 1998; 18: 35-47.

NOTE:
Medicine is a constantly changing science and not all therapies are clearly established. New research changes drug and treatment therapies daily. The authors, editors, and publisher of this journal have used their best efforts to provide information that is up-to-date and accurate and is generally accepted within medical standards at the time of publication. However, as medical science is constantly changing and human error is always possible, the authors, editors, and publisher or any other party involved with the publication of this article do not warrant the information in this article is accurate or complete, nor are they responsible for omissions or errors in the article or for the results of using this information. The reader should confirm the information in this article from other sources prior to use. In particular, all drug doses, indications, and contraindications should be confirmed in the package insert. FULL DISCLAIMER

Rhinovirus Infection excerpt

© Copyright 2004, eMedicine.com, Inc.



To: Bo Didley who wrote (5155)10/23/2004 2:15:01 PM
From: Frank_Ching  Respond to of 5582
 
"There are over 100 serologic virus types which cause cold symptoms and rhinoviruses are responsible for around 50% of all cases."

Rhinovirus From Wikipedia, the free encyclopedia.
en.wikipedia.org

Rhinovirus
Scientific classification
Kingdom: Virus
(+)ssRNA viruses
Family: Picornaviridae
"rhinoviruses are responsible for around 50% of all cases."

Genus: Rhinovirus

Species
Human rhinovirus A (HRV-A)
Human rhinovirus B (HRV-B)

A rhinovirus is a virus member of the family Picornaviridae. The rhinoviruses are single stranded positive sense RNA viruses. They are the most common viral infective agents in humans. The most well known disease caused by rhinoviruses is the common cold. There are over 100 serologic virus types which cause cold symptoms and rhinoviruses are responsible for around 50% of all cases.

The name comes from the Greek rhin, which means nose.



To: Bo Didley who wrote (5155)10/23/2004 2:22:13 PM
From: Frank_Ching  Respond to of 5582
 
"It is estimated that about one third of "colds" are caused by rhinovirus infections."

216.239.41.104

VIROLOGY - CHAPTER TEN

PICORNAVIRUSES - PART TWO

RHINOVIRUSES


Image © Jean-Yves Sgro. Institute for Molecular
Virology, University of Wisconsin. Used with permission


Rhinoviruses (Rhinos - nose (Greek)) are one of the families of viruses that can cause the common cold although many other viruses can infect the respiratory tract and cause cold-like symptoms. It is estimated that about one third of "colds" are caused by rhinovirus infections. There are more than 100 serotypes explaining why vaccines against rhinoviruses have proved difficult to develop. Rhinoviruses have a diameter of about 30nm and are positive strand RNA viruses with a naked nucleocapsid (figure 1). They are sensitive to low pH and, as might be expected from their symptoms, are spread by aerosols and infect the upper respiratory tract. They can also be spread by fomites such as hands and other forms of direct contact. Rhinoviruses are quite stable, lasting for hours on fomites, but are sensitive to temperature. Thus, they do not spread to the lower respiratory tract since they replicate best at a few degrees below normal body temperature. Although the most common route of infection is the nose, virus can also enter via the mouth and the eyes. There is usually no gastrointestinal involvement because of the acid lability of the virus. The virus is therefore not spread from the intestinal tract.
RHINOVIRUS DISEASE

There are nearly 62 million cases of the common cold annually in the US

52.2 million of these cases affect Americans under age 17

There are nearly 22 million school-loss days annually due to the common cold

There are approximately 45 million bed days annually associated with the common cold

Seventy-five percent of common colds suffered by children under 5 years are medically attended
Source: Vital and Health Statistics Series 10, No. 200

The symptoms of a rhinovirus infection are well known: discharging or blocked nasal passages often accompanied by sneezes, and perhaps a sore throat. This typical "runny nose" (rhinorhea) may be accompanied by a general malaise, cough, sore throat etc. The characteristic symptoms occur from one to four days after infection at which time extremely high titers of the rhinovirus are found in the nasal secretions (there can be as many as 1000 infectious virus particles per ml). It appears that one rhinovirus infectious virion particle is capable of initiating disease. The virus replicates itself primarily in epithelial cells of the nasal mucosa but there is little damage to the mucosa although infected cells may be sloughed off. There may be edema of connective tissue.

The symptoms experienced depend on the number of virus particles replicated. Infected cells produce a variety of molecules that such as histamine that result in increased nasal secretions. It is the production of such molecules rather than direct cellular destruction to accounts for the symptoms experienced by the patient. These molecules cause changes in vascular permeability

The primary infection results in IgA in nasal secretions and IgG in the bloodstream. Since these viruses do not enter the circulation, the mucosal IgA response is the most important. This leads to immunity and resolution of the disease although the levels of nasal IgA are rapidly reduced. Immunity against a particular serotype may last 1 to 2 years but as noted above there are many serotypes against which protection is not gained. As with infections by other viral infections, interferon production is the primary means of defense, preceding the antibody response. Interferon production may lead to the symptoms experienced by the patient (see Virus-Host Interactions). Many infected persons (about 50%) do not show symptoms of a rhinovirus infection but are nevertheless capable of passing on the infection. Although the lower respiratory tract is usually not affected, bronchopneumonia can occur in rhinovirus infections, particularly in children.


Figure 1 Human rhino virus © Dr J-Y Sgro, University of Wisconsin. Used with permission
EPIDEMIOLOGY

Rhinovirus infections usually occur at times of increased human contact, that is in the colder months of the year. Many different serotypes circulate simultaneously. Frequently children become infected and then pass the virus to adults after an incubation time of about two or three days. Often as many as one half of the contacts get a cold in this way. Antigenic variation occurs.

Many infections by other viruses cause symptoms that are similar to those of rhinoviruses. These include parainfluenzaviruses, coronaviruses and enteroviruses

RECEPTORS

Most rhinoviruses bind to a member of the immunoglobulin super-family of proteins, ICAM-1 which is found on the surfaces of epithelial and other cells. This molecule mediates cell-cell adhesion in a variety of epithelial cells. The expression of ICAM-1 is enhanced under inflammatory conditions such as occur in a rhinovirus infection which may lead to viral spread because of more available receptor molecules (positive feedback loop). Because of the specificity to ICAM-1, only humans are infected by human rhinoviruses.



Figure 2 Human diploid fibroblasts infected with Rhinovirus (100X). © Danny L. Wiedbrauk, William Beaumont Hospital, Royal Oak, Michigan USA and The MicrobeLibrary CULTURE

If it is necessary to identify the virus that gives rise to the typical "cold" symptoms, virus can be grown on cultured cells from nasal specimens. Usually, human fibroblasts are used and the laboratory looks for a typical cytopathic effect of refractile cells (figure 2). The cells are grown at around 33 degrees.

DIAGNOSIS

Many types of viruses give "cold"-like symptoms and it is usually unnecessary to carry out further identification. Usually it is enough to note the minor symptoms and the seasonal infections. There are specific antibody tests available but these are not generally used.

TREATMENT

There is usually no need to treat the infection although treatment of the symptoms may be used. This often consists of rehydration and keeping the airways unblocked. Physicians often prescribe aspirin to relive fever symptoms but this may exacerbate viral proliferation if body temperature is reduced since, as noted above, the virus is particularly temperature-sensitive. Interferon nasal sprays have little effect. Pleconaril is broadly active against rhinoviruses (see Anti-Viral Chemotherapy). The best way to avoid spreading the virus is interrupt the infection chain by hand washing.



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