|
Influenza A (H1N1) “Swine Flu”
Since April 2009, Influenza A (H1N1) "Swine Flu" has almost literally swept the world, and The World Health Organisation was forced to officially declare the virus a global pandemic on 11 June.
Its spread has been so rapid primarily due to the fact that no individual has previous immunity to this strain of virus, and with large numbers of people expected to be sick over the coming winter, resulting school and workplace absences may have a big impact on all of our day to day lives in months to come (1).
The most recent official update from the World Health Organisation states that as of June 24th there are 386 confirmed cases of Swine Flu in New Zealand (2), and with routine testing being phased out the actual number of infections may be many more.
Considerable pressure may be placed on health care providers, and this makes immune and antiviral support a necessary focus of patient care for all health practitioners. Many practitioners however are uncertain as to the nature of the virus, and the treatment options available. We at ProHerb have therefore compiled some relevant information in order to assist practitioners in making the best clinical decisions for their patients.
The Virus
Transmission
Swine flu is spread via close contact droplet transmission, in a similar way to other influenza viruses. Infected droplets do not remain suspended in the air and generally travel less than two metres. It is unknown how long swine flu incubates within a person, but public health experts believe is it likely to be one to four days, and possibly as many as seven days. Children, especially younger children, might be infectious for up to 10 days (3).
Clinical picture & Complications
So far Influenza A (H1N1) 'Swine Flu' has produced only mild to moderate illness in most people, with symptoms including fever, chills, headache, upper respiratory tract symptoms, myalgias, arthralgias, and fatigue. 40% of swine flu patients have had nausea, vomiting, or diahorrea.
The disease however may lead to more serious complications, particularly in at risk groups including:
· Children under 5;
· People aged 65 and older;
· Pregnant women;
· Adults and children who have chronic pulmonary, cardiovascular, hepatic, hematological, neurologic, neuromuscular, or metabolic disorders;
· Adults and children who have immunosuppression (including immunosuppression caused by medications or by HIV);
· Residents of nursing homes and other chronic-care facilities.
Clinicians should expect complications to be similar to seasonal influenza: exacerbation of underlying chronic medical conditions, upper respiratory tract disease (sinusitis, otitis media, croup) lower respiratory tract disease (pneumonia, bronchiolitis, status asthmaticus), cardiac (myocarditis, pericarditis), musculoskeletal (myositis, rhabdomyolysis), neurologic (acute and post-infectious encephalopathy, encephalitis, febrile seizures, status epilepticus), toxic shock syndrome, and secondary bacterial pneumonia with or without sepsis. (3)
Treatment
Treatment via inhibition of viral replication: Neuraminidase and Haemagglutinin
There are two major proteins on the surface of influenza virus particles: Neuraminidase and haemagglutinin.
Influenza neuraminidase exists as a mushroom-shape projection on the surface of the influenza virus. The neuraminidase cleaves the cellular receptor sialic acid residues where the budding, newly formed viruses are attached. This cleavage releases the progeny viruses that now can invade new cells for further replication. Without neuraminidase the infection would be limited to one round of replication, which rarely is enough virus to cause disease. Neuraminidase may also help the viral invasion of the upper airway cells by cleaving the sialic acid moieties on the mucin that bathes the airway epithelial cells making them more vulnerable to attack.
Haemagglutinin mediates the attachment of the virus to host cells. Minor changes in haemagglutinin occur through point mutations in the viral genome (antigenic drift). Major changes occur as the result of wholesale swapping of genetic material with reservoirs of different viruses in other animal hosts (antigenic shift-e.g. in the case of swine flu)
· Tamiflu works by inhibiting neuraminidase.
· Neuraminidase is also inhibited by Baical skullcap (Andrographis Compound).
· Haemagglutinin is inhibited by cyanidin from Elderberry (Elderberry BioComplex).
· The effect of St John’s Wort on neuraminidase and haemagglutinin is unknown at this stage, however its antiviral action is believed involve the interaction of hypericin with one or both of these proteins.
Elderberry
Sambucus nigra has long been recognised as a valuable plant in the treatment of colds and flu. However extracts of the berries and flower of the Elder tree have very different properties and are not to be confused.
Elderflower is useful in treating colds and flu due to its anticatarrhal and diaphoretic actions, but it does not posses any active antiviral properties. It is the Elderberry extract which actively fights viral infection, and this may be linked to the presence of the cyanidin base cyanidin-3-O-glucoside.
Elderberry extract is based on the dried juice of the elderberry. The cyanidin is only stable in dry form.
Elderberry contains only one cyanidin base, namely cyanidin-3-O-glucoside. Cyanidin is a particular type of anthocyanidin, not to be confused with anthocyanins which are glycosides of anthocyanidins. Of all the anthocyanidins, Cyanidin-3-O-glucoside (kuromanin) has been found to have the highest ORAC (oxygen radical absorbance capacity) activity, therefore in addition to their antiviral effect Elderberries also possess powerful antioxidant ability.
Cyanidin-3-O-glucoside has been shown in vitro and in vivo to have the following effects:
· Anticancer (increases apoptosis, chemoprotective, reduces tumour growth and metastasis).
· Gastroprotective
· Antioxidant
· Antiviral
· Antihyperglycaemic, increases insulin sensitivity
· Anti-inflammatory
“The ability of Elderberry to inhibit a wide range of influenza viruses from both humans and animals suggests that it may be effective against mutated viruses, making it an extremely valuable medicine in the event of an influenza epidemic or pandemic.”
Important Note: The active chemical constituent of Elderberry, Cyanidin, is not naturally stable in liquid form. Therefore ProHerb do NOT stock a liquid extract of Elderberry. Instead we are pleased to offer a stable, high quality dried extract in tablet form as Nutrimedicines “Elderberry BioComplex”
For more information about Elderberry contact nzhealthshop kirsten@nzhealthshop.co.nz
St Johns Wort
The antiviral action of St Johns Wort is thought to be linked to activity of hypericin and pseudohypericin, however the mechanism of action is as yet uncertain. Hypericin appears to act via interference with the viral cell membrane or cell surface recognition sites.
A very recent study found that a St John’s wort extract inhibited human influenza A virus (IAV) strain (H1N1) in vitro and in vivo, the same virus family which is causing the Swine flu. In the study, the antiviral effect of St John’s wort was compared to the antiviral drug, Ribavirin. Ribavirin interferes with RNA metabolism required for viral replication and St John’s wort may work in a similar way.
A dose of 2.7mg hypericin (900mg St Johns Wort) per day (equivalent to three MediHerb St Johns Wort tablets) has been shown to be effective as a preventative dose in the treatment of herpes simplex viruses, with double this dose to be used during acute outbreak (4)
Andrographis
Studies have shown Andrographis paniculata to both to enhance immune function and to alleviate the symptoms of colds and flu. Andrographolide stimulates Natural Killer (NK) cells, antibody-dependant cellular cytotoxicity, and antibody-dependant complement-mediated cytotoxicity. It also inhibits expression of a variety of inflammatory proteins.
One randomised, double blind study found that 1200mg/day for 5 days of an Andrographis extract had a high degree of effectiveness in reducing the prevalence and intensity of the symptoms of common cold. It appears to be particularly effective in reducing throat signs and symptoms.
Digestive Enzymes: Proteases & The Protein Coat
“All viruses are alike in that they have protein coats containing nucleic acid… Enzymes fight viruses by breaking up this protein” (Anthony J Cichoke)
Protease is a classification of a group of enzymes which act on protein molecules and assist in catalyzing reactions. These reactions, in effect help to change the molecular structure, or break down the protein molecules. Based on clinical studies, it is known that proteases are able to dissolve almost all proteins as long as they are not components of living cells. Normal living cells are protected against lysis by the inhibitor mechanism. Viruses, parasites, fungal forms, and bacteria are either protein or protected by protein. The introduction of oral proteases presents the ability of those enzymes to act upon the protein coating of viruses or any protein that is harmful to the body or does not belong. Enzymes can also break down undigested food protein, cellular debris, and toxins in the blood, sparing the immune system this task. The immune system can then concentrate its full action on the bacterial or parasitic invasion.
It should be noted that proteases when taken on an empty stomach are readily taken up into the mucosal cells of the intestine and passed into the blood circulation. Clinical observations have noted that upon high intake of oral protease, heavy metal concentrations have been significantly decreased in the blood. While in the blood, proteases are take up by alpha II-macroglobulin which ensures its survival in the body. This same alpha II-macroglobulin escorts the protease throughout the body and appears to have the same ability that white blood cells have for determining what does not belong. Once identified the alpha II-macroglobulin exposes the protease to the protein invader and digestion of that protein begins. (Robert McIlroy)
For more information about Digestive Enzymes contact ProHerb
Tamiflu
Tamiflu (Oseltamivir) may help to prevent and/or treat viral infection via inhibition of viral neuramidase. If a patient has been prescribed Tamiflu, it is unlikely that herbal medicines such as Elderberry, Echinacea or Andrographis will interact with its metabolism or cause any danger. Therefore concurrent herbal treatment may still be appropriate.
As Tamiflu is not metabolised by the same cytochrome P450 enzymes, St Johns Wort is unlikely to interact with this drug.
Side effects of Tamiflu may include nausea, vomiting, abdominal pain and headache (5)
Treatment protocols for Acute Infection
Lifestyle Enzymes Inflamase: 2 capsules 4 times per day on an empty stomach (1 hour before, or two hours after food)
MediHerb St Johns Wort: 3-6 tablets per day, or 7-13 mls per day High Grade Liquid Extract (equivalent to 2.7mg-5.4mg hypericin). Please note: at higher doses patients should be warned of the possibility of increased photosensitivity.
Nutrimedicine Elderberry BioComplex: 2 tablets twice per day (adult dose), or 1 tablet twice per day (children)
MediHerb Andrographis Complex: 2 tablets three to four times per day
Nutrimedicine Andrographis Compound: Containing Echinacea, Andrographis, and Baical Skullcap, this antiviral formula may provide symptomatic relief as well as enhanced immune function. 1 tablet 2-3 times per day.
MediHerb Herbal Throat Spray: 4 sprays as needed for relief of sore throats & local antimicrobial activity. Also useful to protect against viral invasion, particularly during travel or in crowded places.
|
