Jul
25
2020

The Immune System Changes With Age

By | autoimmune disease, diet, fish oil, food, immune system, Infectious Disease, lifestyle, omega-3 fatty acids, vaccinations, Vitamins and supplements

When we are young, we do not think about our immune system, but the immune system changes with age. When we are older than age 60, we notice that we may be taking longer to recover from a flu.

How does the immune system work?

There are two parts to the immune system, the innate immune system and the adaptive immune system. The innate immune system works to protect us from bacteria, viruses, toxins and fungi from the time we are born. The adaptive immune system uses B lymphocytes from the bone marrow to produce antibodies against viruses. This provides often lifelong immunity against this specific virus, but takes 3 to 5 days to kick in. Vaccinations can also trigger antibody production to protect us from viruses in the future. Both the adaptive and the innate immune system work together closely.

What are the ingredients for a fully functioning immune system?

The immune system consists of various immune organs that are distributed throughout the body. The bone marrow produces lymphocytes, granulocytes, macrophages, eosinophils and basophils. The adenoids in the back of the nasal passages and the tonsils in the back of the throat contain a lot of lymphocytes that are ready to protect us from colds and flus. We have lymph nodes throughout the body and they are connected with lymphatic vessels. The lymph nodes filter the lymph fluid that travels in the lymphatic vessels.

Other sites of lymphocyte production

The small intestine contains the Peyer’s patches, a collection of lymphocytes that protect our gut from invading bacteria or viruses. The spleen is located in the left abdominal cavity under the diaphragm. It removes old red blood cells and provides lymphocytes for the immune system. The thymus gland is located between the breast bone and the trachea. It changes bone marrow derived lymphocytes (B cells) into T lymphocytes that can process antigens from viruses and pass them on to the adaptive immune system for a full antibody response.

Cellular interactions between various players of the immune system

Back in the 1970’s it was already known that there were bone marrow derived B lymphocytes and thymus processed T lymphocytes. We knew then that B cells were involved in antibody production (adaptive immunity). T lymphocytes were thought to turn into killer T lymphocytes to kill cancer cells. But some T cells were T helper cells to process antigen and present it to B lymphocytes for antibody production.

More research since then refined what we know about the cells of the immune system.

Natural killer cells (NK cells)

Natural killer cells (NK cells) are part of the innate immune system. They attack cancer cells and cells that are infected by viruses. It takes about 3 days for their full action to develop. NK cells utilize the cell surface histocompatibility complex to decide whether to destroy a cell or not. T cell lymphocytes do not have the ability to do that. In the Covid-19 coronavirus situation NK cells play an important role to combat the disease right away.

Monocytes

They are large white blood cells that can differentiate further into macrophages and dendritic cells. Monocytes are part of the innate immunity, but they have an antigen presenting capability, which makes them also part of the adaptive immunity.

Memory T cells

The immune system learns to adapt to viruses and bacteria that we have come in contact with. The reason for the memory of the immune cells are the memory T cells. They replicate like stem cells, which keeps a clone of T lymphocytes, T helper cells and cytotoxic T killer cells in the background. They circulate through the body including the lymph glands and the spleen.

Immunosenescence as we age

There are several factors that come together, which age our immune system. The term for this is “immunosenescence“. There are genetic differences and differences due to the sex hormones. Estrogens increase the response of the immune system. In contrast, progesterone and androgens (including testosterone) decrease the immune response. This may be the reason why women tend to live longer than men.

As we age there are more and more memory T cells (both cytotoxic T cells and T helper cells). This weakens the formation of the natural killer cells (NK cells) of the innate immune system. Even the initiation of the adaptive immune system can be slower when we age and also the response to the flu vaccine. In addition, this can pave the way to autoimmune diseases.

The immune system changes with age: Evidence of immunosenescence

The following 3 factors show whether a person has immunosenescence:

  • The immune system has difficulties to respond to new viruses/bacteria or to vaccines
  • Accumulation of memory T cells crowding out cells of the rest of the immune system
  • Low-grade inflammation that is chronic and persists (“inflamm-aging”)

The process of immunosenescence starts with the involution of the thymus gland around the time of puberty. At that time the sex hormone secretion is highest. At the same time a growth factor from the bone marrow and the thymus gland decreases. It has the name interleukin-7 (IL-7). The end result is a slow decrease of the innate immune system with age and a more substantial weakening of the adaptive immune system due to a lack of naïve T and B cells. 

Chronic viruses can weaken the immune system further

The varicella herpes zoster virus causes chickenpox. In some people the chickenpox virus can persist, but the immune system actively keeps it controlled. In the 60’s or 70’s when the immune system is weakened from aging, there can be a flare-up as shingles, a localized form of the chickenpox virus.

Another virus, the human cytomegalovirus can cause a chronic infection that often persists lifelong. In this case the immune system is chronically weakened because of a massive accumulation of T memory cells, which keeps the human cytomegalovirus infection at bay.

What we need when the immune system changes with age 

Vitamin A

Both the innate and adaptive immunity depend on vitamin A and its metabolites. The skin cells and mucosal cells function as a barrier, which is important for the innate immunity. The skin/mucosal lining of the eye, the respiratory tract, the gastrointestinal and genitourinary tracts help the innate immunity to keep viruses and bacteria out of the body. Vitamin A is important to support macrophages, neutrophils and natural killer (NK) cells. In addition, vitamin A supports the adaptive immune system, namely T and B lymphocytes, so that the body can produce specific antibodies against viruses.

I do not take vitamin A supplements as I eat diversified foods like spinach, vegetables, poultry, Brussels sprout, fish and dairy products that contain vitamin A and carotenoids.

Vitamin C

This vitamin is a powerful antioxidant. It can neutralize reactive oxygen species, which are produced when the immune cells fight viruses and bacteria. Neutrophils, lymphocytes and phagocytes are all supported by vitamin C. Vitamin C and E co-operate in their antioxidant functions. Vitamin C is essential for a strong antibody response with bacterial or viral infections. I take 1000 mg of vitamin C once daily.

Vitamin D

The immune system is very dependent on vitamin D as the immune cells all contain vitamin D receptors. People who have less than 10 ng/mL of vitamin D in the blood are vitamin D deficient. They have much higher death rates when they get infected with the Covid-19 coronavirus.

Vitamin D regulates the expression of target genes. At the center is the vitamin D receptor, which is a nuclear transcription factor. Together with the retinoic X receptor (from vitamin A) the vitamin D receptor binds small sequences of DNA. They have the name “vitamin D response elements” and are capable of initiating a cascade of molecular interactions. The result is a modulation of specific genes. Researchers identified thousands of vitamin D response elements that regulate between 100 and 1250 genes.

You need enough vitamin D for your immune system

When enough vitamin D is present in the blood (more than 30 ng/mL) the immune system releases the peptides cathelicidins and defensins, which effectively destroy bacteria and viruses.

Vitamin D has mainly an inhibitory function regarding adaptive immunity. It inhibits antibody production from B cells and also dampens the effect of T cells. Researchers reported that vitamin D3 is useful in the treatment of autoimmune diseases.

I am a slow absorber of vitamin D3 as repeat blood vitamin D levels showed. I need 10,000 IU of vitamin D3 daily to get a blood level of 50-80 ng/mL (=125-200 nmol/L). This is the higher range of normal. Everybody is different. Ask your physician to check your blood level of vitamin D. Toxic vitamin D blood levels are only starting above 150 ng/mL (= 375 nmol/L).

Vitamin E

This is a vitamin that is fat soluble and helps the body to maintain its cell membranes. But researchers found that vitamin E also stimulates the T cell-mediated immune response. This is particularly important for the aging person to prevent respiratory tract infections. I take 125 mg of Annatto tocotrienols per day (this is the most potent form of vitamin E).

Vitamin B6

This vitamin is important for antibody production by B cells. Vitamin B6 regulates the metabolism of amino acids, which in turn form proteins. Antibodies and cytokines require vitamin B6. The T helper immune cells that initiate an adaptive immune response depend on vitamin B6 as well. I take a multi B complex vitamin (Mega B 50) twice per day, so I supplement with a total of 100 mg of vitamin B6 daily.

Folate

Folic acid is a coenzyme for the metabolism of nucleic acids and amino acids. Studies in humans and animals have shown that folate deficiency leads to increased susceptibility to infections. People with folate deficiency develop a megaloblastic anemia with immune weakness that leads to chronic infections. With my B complex supplement I get 2 mg of folic acid daily.

Vitamin B12

Methylation pathways depend on vitamin B12 as a coenzyme. Vitamin B12 is also involved as a coenzyme in the production of energy from fats and proteins. In addition, hemoglobin synthesis depends on vitamin B12. Patients with vitamin B12 deficiency develop pernicious anemia. These patients also have a weak immune system due to natural killer cell activity suppression and because circulating lymphocyte numbers are significantly decreased.

Treatment with cyanocobalamin reverses the immune weakness rapidly and treats pernicious anemia at the same time. I take 50 micrograms twice per day as part of the Mega-B50 multivitamin tablet. But I also inject 1000 micrograms of vitamin B12 every 6 months subcutaneously to be sure it is absorbed into the body. In older age the intrinsic factor from the stomach lining, which is required for absorption of vitamin B12 in the small intestine, can be missing, leading to vitamin B12 deficiency despite swallowing supplements.

Minerals required for a good immune response

Researchers identified five minerals that are essential for a strong immune system. They are zinc, iron, selenium, copper and magnesium.

Zinc

Zinc is important for a normal function of the innate and adaptive immune system. As zinc cannot be stored in the body, taking regular zinc supplements (30 to 50 mg daily) is important. I take 50 mg of amino acid chelated zinc daily.

Iron

Iron is important for cell oxygen transport and storage, DNA synthesis and for mounting an effective immune response. In particular it is the T cell differentiation and proliferation where iron is needed. Iron deficient people get a lot of infections because the immune system is paralyzed. I eat one spinach salad or steamed spinach daily, which gives me enough iron supply per day.

Selenium

Selenium is a trace mineral that is important for a normal immune response and for cancer prevention. When selenium is missing, both the adaptive and innate immune system are suffering. In this case viruses are more virulent. With selenium supplementation cell-mediated immunity is improved and the immune response to viruses is more potent. I take 200 micrograms of selenium per day.

Copper

Deficiency in copper results in a very low neutrophil blood count and causes susceptibility to infections. Copper is a trace mineral that participates in several enzymatic reactions. It is important for the innate immune response to bacterial infections. A well-balanced Mediterranean diet contains enough copper, which is why I do not supplement with extra copper.

Magnesium

An important cofactor for vitamin D in the body is magnesium. Magnesium participates in many enzymatic reactions. Between vitamin D and magnesium, the immune system is strengthened. I take 150 mg of magnesium citrate twice per day. By the way, magnesium also helps us to get a restful sleep, if we take it at bedtime.

Other dietary factors that strengthen the immune system

Polyunsaturated omega-3 fatty acids

It is important to note that polyunsaturated omega-3 fatty acids are essential for the body and help to modulate the immune system. I take 1800 mg of omega-3 (EPA/DHA) twice per day. I also like to eat fish and seafood at least 3 times per week.

Probiotics

Prebiotics benefit both the innate and the adaptive immune system. They strengthen the epithelial gut barrier, which is an important innate immune defence. Probiotics also lower the risk for Clostridium difficile gut infections. I take one probiotic every morning.

The Immune System Changes With Age

The Immune System Changes With Age

Conclusion

The immune system consists of different organs like the bone marrow, the spleen, lymph glands, Peyer’s patches in the gut, the thymus gland and more. There is the innate immune system, which responds immediately to a virus like the Covid-19 coronavirus. The adaptive immune response involves antibody production against, for instance, the measle virus or the mumps virus. With the aging process the immune system slows down (immunosenescence). This involves an accumulation of memory T cells and a depletion of natural killer cells (NK cells). This means that the innate immunity is getting weaker as we age and chronic inflammation occurs more often. This is the reason why people above the age of 65 get more severe symptoms from the Covid-19 coronavirus. They are also more affected by influenza-type illnesses.

Take supplements to strengthen the immune system

I reviewed the cofactors of a healthy immune system in some detail. It is important that you pay attention to these, particularly the vitamin D3 intake. With a strong immune system, we can survive viral infections better, including the current Covid-19 coronavirus. Future research will likely detect how to reactivate a sluggish immune system in older people. This way vaccination responses following flu injections will become more reliable in seniors.

Oct
05
2013

Fighting Back Against The Flu

By | Fitness, Infectious Disease, Lung Disease, Nutrition, Prevention, Stress management, Vitamins and supplements

Every year there is concern about the upcoming flu season. Mostly the discussion centers on the composition of the latest flu bugs and what type of strains would be included in the latest vaccine recommended. The first flu case of the season has just been reported in a child. Here I am going to review what you can do to minimize your probability of getting the flu, or if you get it, how to minimize the severity of the illness.

The immune system

We know for some time that the antibody-mediated immune system is what helps overcome flus. The body’s immune system produces antibodies against the flu via T-helper cells that recognize the glycoprotein (hemagglutinin) of the flu virus and pass a signal on to B cells (bone marrow derived lymphocytes), which in turn are turned on to produce a lot of antibodies (Ref.1). These protect you from future flus of this type. If you have pre-existing antibodies that fit the bug in circulation you are OK ,and you will usually not get the disease.

The factors that protect you from the flu

However, there are many other factors that support your immune system. I will discuss the most important factors in more detail here.

1. We do know that vitamin D3 strengthens the immune system. I would recommend 1000 to 2000 IU per day in the wintertime, but up to 4000 IU or 5000 IU per day during an active epidemic would be reasonable. There is less flu when people are taking Vitamin D3 supplements.

Influenza A was reduced in school children supplemented with 1200IU of vitamin D3. This study recommended higher doses of 2000 to 7000 IU of vitamin D3 per day; but it also stated that as a precaution serum vitamin D levels should be monitored (technically it is serum 25-hydroxy-vitamin D levels that are measured) to avoid vitamin D toxicity. Normal levels are between 40-70 nanograms per ml. Toxic levels are above 100 nanograms per ml. Your family doctor can order a serum 25-hydroxy-vitamin D level for you.

2. Eating fruit and vegetables is important for maintaining a healthy immune system. In a randomized study from Belfast, UK elderly volunteers (82 of them, aged 65 to 85) were assigned to either eat 2 portions or 5 portions of fruit and vegetables per day over 16 weeks. At 12 weeks into the trial both groups received a Pneumovax II vaccination, and the antibody response was measured at the end of the 16th week of the study.  There was a significant increase in antibody binding capacity to pneumococcal capsular polysaccharide in the 5 portion fruit and vegetable group compared to the 2 portion group that had no such increase. The authors concluded that there is a measurable improvement of the immune system when an older population increases their fruit and vegetable intake.

3. Avoid stress, because stress has been shown to weaken the immune system. This review shows that the immune system is weakened by the stress response via the elevated corticosteroid hormones (the stress hormone ACTH stimulates cortisol release from the adrenal glands). The stress of social isolation is also contributing to the weakening of the immune system in older people.

Fighting Back Against The Flu

Fighting Back Against The Flu

4. Exercise moderately and your immune system will get strengthened. Over exercising should be avoided as too much cortisol is released from your adrenal glands, which is toxic to lymphocytes thus weakening your immune system.

5.  Socializing is good for you as studies have shown that you live 2 ½ years longer. This study here is from Connecticut, but other studies confirmed this as well.

6. Make love. The endorphins that are released in the process stimulate the immune system.

7. Take probiotics, because they help your gut flora to stay normal. A normal gut flora promotes a stronger immune system as the Peyer’s patches (clumps of immune cells) in the gut wall are intimately linked to the immune system. In this way probiotics indirectly support your immune system.

8. Avoid smoking.  Smokers have more upper and lower respiratory tract infections than non-smokers. Here is information that explains this as well.

9. Get enough sleep. The circadian rhythm of your hormones ensures that your hormones function at their optimal level. Melatonin from the pineal gland is important in triggering the circadian rhythm, but melatonin itself supports the immune system as well. Your adrenal glands need resetting overnight so that cortisol is secreted according to your stress level, not too much and not too little. Overstimulation from performance sports, grief reactions, car accidents, injuries etc. lead to a surplus of cortisol and weakening of the immune system.

10. Take your flu shot (but without thimerosal) every year, but take it as a single shot (without thimerosal as a preservative). This CDC link explains that single shot flu vaccines are available without thimerosal. I recommend this type of flu vaccine. The central nervous system is extremely sensitive to nanograms of mercury, and it is for this reason that I would not buy into the argument of the CDC that one should not be concerned about safety of thimerosal. The newest for this flu season is the quadrivalent (or four-strain) flu vaccine, which is now available in pharmacies throughout the US.

11. Vitamins and supplements support your immune system, particularly vitamin D3. DHEA, which is available over the counter in the US stimulates antibody production when the flu vaccine is given, particularly in the elderly, in other words DHEA strengthens the immune system Vitamin C is known to support the immune system and is rapidly depleted in those who suffer from any viral infection. There are other nutrients that are useful to stimulate your immune system.

12. Consider herbs: Echinacea, Siberian ginseng, Asian and American ginseng, astragalus, garlic, and shiitake, reishi (also called “lingzhi mushroom”) and maitake mushrooms have all been shown to stimulate the immune system with negligible side effects.

13. Wash your hands, particularly when there is a flu going around. Door knobs for instance are known to keep live viruses for 2 to 8 hours, so washing your hands will reduce the amount of virus you are exposed to.

Conclusion

There is no single solution to prevent the flu, but we can all minimize our exposure to the virus and strengthen our immune system. Although it is wise to get a yearly flu shot to boost your immune system (without thimerosal as a preservative) just before the epidemics come around, this alone is not as good as combining the non-specific factors mentioned here with it. Particularly vitamin D3 (2000 IU to 4000 IU per day) and the old stand-by vitamin C (1000 mg to 2000 mg daily) will stimulate your immune system. Spice up your dinners with mushrooms that stimulate your immune system (maitake, shiitake, reishi mushrooms). Go to bed early enough to allow your circadian hormone rhythms to be reset overnight as you sleep. This will stimulate your immune system (from melatonin and DHEA of your adrenal glands).

More info on the Flu: http://nethealthbook.com/infectious-disease/respiratory-infections/flu/

References:

1. Long: Principles and Practice of Pediatric Infectious Diseases, 4th ed. Prevention. Vaccine. © 2012 Saunders

Last edited Nov. 7, 2014

Oct
01
2006

Antiviral Drugs Not For Flu Prevention

By | Infectious Disease, Lung Disease, Prevention

With the arrival of the fall and winter season concerns about viral illnesses crop up. The most common ailment is the flu, which occurs seasonally. Prevention measures come in the forefront, and over-the-counter remedies and herbal supplements make their appearance.
Yet at this point the most effective measures remain very basic: good hygiene, hand washing, non-exposure to people who have the flu and non-sharing of personal items that could carry the virus. Flu shots for flu prevention remain the single most effective way to prevent widespread epidemics.
Antiviral agents zanamivir (also known as Relenza) and oseltamivir (Tamiflu) have come under discussion. They have been very effective in the treatment of influenza symptoms. It is not too late to treat with oseltamivir after the patient has been infected with the flu, as the drug prevents lower respiratory tract complications. For the symptomatic relief of influenza 75 mg per day were 61% effective, and 150 mg were 73% effective. Using the drugs strictly as a prophylaxis proved to be a fallacy. Results showed that neither zanamivir nor oseltamivir prevented influenza-like illnesses.

Antiviral Drugs Not For Flu Prevention

Antiviral Drugs Not For Flu Prevention

Even though both antiviral agents are not 100 % effective, they still can be useful in the setting of a flu pandemic. They are also of help in population groups with chronic health problems or immunocompromised persons to whom any viral infection can be serious.

More info about the flu: http://nethealthbook.com/infectious-disease/respiratory-infections/flu/

Reference: The Medical Post, September 1, 2006, page 61

Last edited November 1, 2014

May
01
2005

Bird Flu Can Affect Humans

By | Infectious Disease, Lung Disease

Avian Influenza has received significant attention in the media: some articles label it as the new threat in influenza viruses, while others dismiss it as ” only a flu that will infect birds.” Outbreaks have been reported mainly from Asia, but the nasty virus has made it into poultry farms in North America. There is concern that avian influenza could be transmitted from uncooked birds or bird products onto humans. Avian influenza A has indeed been detected in imported frozen duck meat and infected poultry eggs.
Of particular concern is the virus strain H5N2, as it has the propensity to mutate rapidly. At this point the risk of human-to-human, and transmission remains low, but acquiring the infection from sick birds is a reality. The course tends to be more severe in people older than 12 years, while the disease in children tended to be milder and self-limiting. The symptoms in the adult age group presented as follows:
-Fever (100% of the affected patients)
-Upper respiratory tract infections (67%)
-Pneumonia (58%)
-Gastrointestinal symptoms (50%)
Abnormal laboratory test results were:
-Elevated serum aminotransferases (50%)
-Pancytopenia and bone marrow hemophagocytosis (16%)
Guidelines from the Center for Disease Control suggest that travelers to countries experiencing outbreaks of avian flu should avoid areas with live poultry (live animal markets or poultry farms).

Bird Flu Can Affect Humans

Bird Flu Can Affect Humans

Hand hygiene in the form of soap and water or alcohol-base hand sanitizers is important. All poultry products should be cooked, as heat is effective in killing viruses. It is also important to inform the health care provider about flu-like symptoms associated with recent travel; so avian influenza can be considered.
The current influenza vaccines have no protective value against the avian flu. Studies suggest that anti-viral prescription medication may work. As the viruses are becoming resistant to current medications, they are expected to have limitations in successful treatment.

More info about the Flu: http://nethealthbook.com/infectious-disease/respiratory-infections/flu/

Reference: The Canadian Journal of CME, April 2005, page 49

Look for more info about the bird flu at the CDC site of the US

Last edited October 28, 2014

Feb
01
2005

News About The Flu

By | Infectious Disease, Lung Disease, Prevention

Every couple of years new influenza strains seem to develop in Asia and spread thru the rest of the world. When summer comes, the flu season is forgotten and the cycle repeats itself in fall and winter.

Recently there were local outbreaks of two avian influenza strains that according to the name should only affect birds (the “asian bird flu”). Based on research from these two bird flu experiences there seems to be a new way of looking at the development of human influenzas. It appears that new strains of human influenza are born in the bird population of Asia where the virus mutates into new strains. From there it spreads into human care takers (bird-to-human spread) and their contacts. Eventually the virus adapts to the human host and effective human-to-human transmission is incorporated into the DNA of the virus. Now the time is ready for a flu epidemic. It is not clear yet how long this human-to-human transmission switch takes (how many months or years). Here are more details regarding the recent two local outbreaks of asian bird flus:

1. Recently Dr. Arnold Bosman published a study in Holland. He was the health officer in charge of investigating an outbreak of influenza A, type H7N7, affecting a number of chicken farms in Holland between March and May 2003. This was the time of the SARS epidemic that caught all of the media attention at that time. About 86 poultry workers had been infected with flu like illness that caused a viral conjunctivitis of the eyes. However, one veterinarian who was in close contact with the infected birds died from respiratory distress syndrome. Using very sensitive PCR facilitated DNA test they were able to show that these infected people had all the same bird flu with the influenza strain A (type H7N7). When contacts of these people were tested a surprisingly large number, about 1000 with an estimated total of about 2000, people were also positive for antibodies to this particular more harmless strain of bird influenza.

2. The second development is regarding the recent infection of a bird flu in Vietnam that has caused many deaths. This is a much more aggressive influenza A (H5N1), which is the other bird flu that is of concern for the rest of the world. In Vietnam this bird flu type has a mortality of 76%, in other words with this new type of flu 3 out of 4 people die who get it. It all started in December of 2003 and here are the latest details about this flu type.

News About The Flu

News About The Flu

With the new study from Holland the concern among infection specialists is that there likely are a lot more healthy appearing people who become carriers of the disease (like the 2000 contacts in Holland). Experts feel that this type of flu presently might be in the stage of adapting to the human-to-human transmission mode (so far mostly bird-to-human transmission has taken place, which is still a barrier to mass transmission). When the virus has learnt to adapt to human-to-human transmission, there could be a flu pandemic with a new human strain of influenza A (type H5N1) that would rapidly sweep the world.

A Quebec/Canada company (ID Biomedical) is working on an influenza vaccine for the H5N1 virus, in preparation for a possible pandemic. The demand will be so great when a pandemic would happen, that the company is thinking of stockpiling this vaccine so that it would be available when bad news should strike.

In the meantime antiviral antibiotics such as Tamiflu (=oseltamivir) at a dose of 75 mg twice per day for 5 days started within the first two days of the flu aborts the flu effectively according to the experts. Unfortunately this antiviral antibiotic directed against the N1 component of the virus is expensive.

More background information about the flu (medically termed “influenza”): http://nethealthbook.com/infectious-disease/respiratory-infections/flu/

Reference: The Medical Post, Jan. 18, 2005, P. 2 and 56

Last edited October 27, 2014

Dec
01
2004

New Drug Zaps the Avian Flu

By | Infectious Disease, Lung Disease, Prevention

Introduction

Flu shots are considered the most useful precaution to control influenza, but a new drug zaps the avian flu, Tamiflu.  The avian influenza virus threatens commercial chicken flocks. This influenza type has the ability to infect humans as well; it has been a threat in Asian countries. Current influenza vaccinations do not provide immunity against the avian flu. The annual vaccination programs cannot possibly target all of the various types of influenza viruses.

Tamiflu effective against influenza A, B and avian flu viruses

British researchers have found that the neuraminidase inhibitor, which is effective against all subtypes of influenza A and B viruses, is also effective against avian influenza viruses. Senior scientist Shobana Balasingam from Queen Mary School of Medicine in London states that there is no current vaccine available should a pandemic influenza of the avian flu subtype H5N1 emerge.

New Drug Zaps Avian Flu

New Drug Zaps the Avian Flu

Tamiflu works best, if the patient takes it 24 to 48 hours after influenza symptoms start.  In two placebo-controlled, double-blind clinical trials 849 adult patients experienced a reduction of flu symptoms of 1.3 days. They started Tamiflu 40 hours after the beginning of flu symptoms. Patients took 75mg for 5 consecutive days. When another group started Tamiflu 24 hours after the onset of flu symptoms, the treatment outcome improved significantly. However, a higher dose of Tamiflu (150 mg twice per day) did not improve the treatment.

Prevention of influenza with Tamiflu

A clinical trial with 1559 non immunized adults showed an overall protection rate of 74% for all groups. There were some locations in Virginia where the infection rate was higher than in the rest of the US. Tamiflu achieved a protection rate of 82%. In cases where no vaccine is available against a new flu type, Tamiflu is a good alternative to protect the population against a new epidemic.

Reference

The Medical Post, November 23, 2004, page 14

Jan
01
2004

Flu Season Not Over Yet

By | Health, Infectious Disease, Lung Disease, Prevention

Influenza type A is the cause of many flu epidemics including the one that recently affected the northern hemisphere. It is known to change its surface characteristics from time to time. This has occurred in the southern hemisphere (Australia and New Zealand) during the summer of 2003 and the same new type has caused the recent epidemic in Canada, the US and Europe.

Prior strains of flu viruses in recent years were variants of the Panama strain, that’s why the infection specialists decided in the beginning of 2003 to suggest a Panama strain type vaccine to be used for protection for this flu winter season. However, 70% of the cases tested in Canada by the end of November turned out to be influenza type A/Fujian,full name A/Fujian/411/2002(H3N2), different from type A/Panama, full name A/Panama/2007/99(H3N2), according to Dr. Theresa Tam. She is a specialist in the division of respiratory diseases at the Health Canada Centre for Infectious Disease Prevention and Control. Similar observations regarding a shift from the type a/Panama to the type A/Fujian strain of the flu virus has also been reported in the US and in Europe. It appears that those who have been vaccinated with the type A/Panama vaccine have had partial protection from this new flu as some of the flu virus characterisitics (e.g. the H3N2 determinants) are the same.

Dr. Tam mentioned that the recent deaths in children from the flu in the US, England and Canada would likely be explained by the fact that in the last 3 years there have not been any H3 type flus and the flus that did circulate were relatively mild. This means that children have not developed enough background resistance to fight a flu when it comes. Most adults have background resistance, but older people are loosing some of the resistance due to aging. Dr. Tam explained that not too many children have had the flu vaccination. One would expect that children are most vulnerable for the flu and this explains why these deaths would have occurred.

Flu Season Not Over Yet

Flu Season Not Over Yet

Production of flu vaccines that protect from flus: One of the problems with getting the best match for an upcoming flu season is the lag period between the decision to produce a certain type of flu vaccine and the mass production of the vaccine to serve a world population. This can take 6 to 8 months. A new technique of vaccine production is being investigated, called “reverse genetics”, where the lag period may only be a few weeks.

Dr. Webster, an infectious disease specialist at the St. Jude Children’s Research Hospital in Memphis, has produced a vaccine with this method against an avian flu with the characteristics H5N1(different from the others mentioned above). This is an older flu transmitted by birds that has resurfaced earlier in 2003 again. However, this vaccine that has been produced in cell culture and not in egg cultures, has only been tested in animal models, not in humans yet. Both Dr. Webster and Dr. Tam agree that human trials under FDA guidelines are needed to test these newer vaccines utilizing reverse genetics. Regulatory and patent issues need to be settled for this to happen.

Use of antiviral drugs: Another issue is that type A influenza can be treated with antiviral antibiotics, but every flu season these types of drugs tend to run short. Each country should have a national stockpile of these antiviral drugs (such as Tamiflu) so that enough stock is available in case of a serious epidemic where the vaccine may not fit the flu strain that comes around. This is not happening at the present.

What is needed is that international discussions take place through the Global Health Security Network (right now consisting of the G7 countries and Mexico), Dr.Tam said.

Conclusion: The flu season has started early this season. Many people have died because of a lack of vaccination. Some of those who were vaccinated against the flu may have caught the flu as the fit this year with regard to the vaccine was not the best. However, they likely survived the flu, whereas those who did not have the vaccine were more likely to have experienced the flu more severely and some of these have died. It is not too late to get the flu vaccine before the spring season. Typically there is another peak of the flu between February and April.

Based in part on The Medical Post, Dec.9, 2003 (p.1 and 73).

Last edited December 8, 2012

Oct
02
2003

Flu Shot Cuts Death Rate Into Half

By | Infectious Disease, Lung Disease, Prevention

An earlier publication in the New England Journal of Medicine in March 2003 has shown that the death rate of people 65 years or older who were vaccinated against the flu, dropped into half when they were exposed to the flu and were compared to non-vaccinated controls. On Oct. 9, 2003 Dr. Megan Wren, associate director of the internal medicine residency at Barnes-Jewish Hospital and Washington University School of Medicine, reminded physicians that with the upcoming flu season it is important to include everybody who is healthy at age 50 or older (as the CDC has suggested now for 3 years) with influenza vaccination . Many physicians are still not aware that the rules have been changed to incude younger persons.

Below are recommendations of who should get a vaccination (in table form).

Dr. Wren pointed out that the risk from a flu vaccination is minimal. Contrary to public belief the flu vaccine does not cause fever, unwellness or muscle aches. The only effect is a mildly sore arm at the site of injection.

Flu Shot Cuts Death Rate Into Half

Flu Shot Cuts Death Rate Into Half

This year the FDA has approved a live flu vaccine that is administered as a nasal spray. This is a live modified flu virus that has been “trained” to only multiply in the colder nasal cavity, but not in the warmer airways. Like with all live viral vaccines pregnant women are not allowed to take this.

Who should get the flu vaccine ?
Group of people:
Comments:
all people age 50 or over the immune system weakens with age, that’s why complications of the flu are more common in this age group
women who will be in the 2nd or 3rd trimester of a pregnancy during November through to March protects the fetus from the flu virus in the most vulnerable period of the  development of the fetus
chronic heart disease or lung disease (including asthma) the flu affects the lungs and the heart most readily
chronic kidney or liver disease these chronic diseases weaken the immune system
people without a spleen and cancer patients the immune system is weak in these patients
children and adults with any chronic disease including diabetes chronic illnesses weaken the immune system in young and old
people on imunosuppressive medications the immune system is weak in these patients
all close family members of any of the above people the CDC hopes that this stops the spread of the flu into this vulnerable group of patients

Dr. Wren also mentioned that people with chronic illnesses, with immune deficiencies (e.g. AIDS and cancer patients) and healthy patients over the age of 50 cannot take this live vaccine. All others from age 5 to 49 can take it, but presently this is still very costly (one nasal mist application in 2003 is about 50.00$ US).

Last edited December 9, 2012

Apr
01
2003

Flu Shots Prevent Heart Disease, Lung Disease, Strokes And Deaths

By | Heart Disease, Infectious Disease, Lung Disease, Prevention, Stroke

It has been known for some time that flu shots would be beneficial. But it was not known until now whether in larger field studies people who are 65 years or older would benefit significantly and to what degree from yearly influenza vaccinations (“flu shots”).

The April 3rd, 2003 issue of The New England Journal of Medicine published the answer to this question. Dr. Nichol from the University of Minnesota, Minneapolis, and his collegues have followed 140,055 patients of whom 55.5% were vaccinated against the flu in the 1998/1999 flu season.

They also followed 146,328 subjects during the 1999-2000 flu season of whom 59.7% were vaccinated against the flu. Below is a breakdown how they fared when compared to non-immunized controls (see table).

Flu Shots Prevent Heart Disease, Lung Disease, Strokes And Deaths

Flu Shots Prevent Heart Disease, Lung Disease, Strokes And Deaths

The examiners of this study concluded that high risk patients (asthma patients, patients with diabetes, cancer, elderly patients, arthritic patients and patients with high blood pressure) should have a yearly Flu vaccination.

Patients after Flu vaccinations. How did they do?
(based on 1998/99 and 1999/2000 flu seasons)
Complications: Observation:
 Comments:
Heart disease: reduced 19% this included heart failure and heart attacks
Hospitalization for stroke: reduced 16% to 23% often hospitalization for stroke patients can be weeks and months, often resulting in other complications due to bacterial superinfections, falls or clots
Pneumonia and
influenza rate: 		reduced
29% to 32%		 this can lead to heart attacks and deaths from bacteria in the blood
Death rates: reduced 48% to 50% all of the deadly complications from getting the Flu remarkably reduced by Flu shots!

However, in my opinion anybody would benefit from regular Flu vaccinations as this boosts the immune system in general protecting against other infections and colds as well.

Here is a link to a chapter on the flu in Net Health Book.

Last edited October 25, 2014