Flu 2017 - The Good News And The Bad News

“Flu season is around the corner. Here’s what to expect this year from the American Council on Science and Health.”

— Dr. Dale

From Flu 2017 - The Good News And The Bad News

New reports out of Australia contain some sobering news. The number of influenza cases this year is 2.5-times that of the same time period last year. Since the flu season down under begins in July, these data may give us a glimpse of what to expect in the US this winter.  New South Wales, which has the highest population of any state in the country, had more than 35,000 confirmed flu cases in August. To put this in perspective, the previous record for most cases in a month was 16,686 this past July. August 2016 had 13,602 cases and August 2015 had 12,901. 

A very bad year

Clearly, the flu is hitting Australia very hard. Does this mean that we are in particular danger this year? Dr. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases (NIAID) says not necessarily, because of the unpredictability of the virus.

"There's nothing really unusual about this year except that it's a high year in Australia, which is what you see every once in a while... [Australia's curve] is clearly much higher than the curve of last year... All the flu-ologists, myself included, say the only thing that you can predict about influenza is that it's going to be unpredictable." 

Dr. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases

Good news, bad news

Although it is troubling to see a record number of cases in Australia, the good news is that this year's vaccine matches quite well with the predominant Australian strain, H3N2 (1). The bad news is that vaccines are less effective against H3N2, which causes more severe disease than most other strains. Dr. Vicky Sheppeard, the director of communicable diseases at the New South Wales Health Department explains:

[Early data indicates the four flu strains in the vaccine are well-matched to circulating viruses,"  [but] It is known that one of the strains in the vaccine [H3N2] is less effective in preventing infection, despite a good match."

Dr. Vicky Sheppeard, the director of communicable diseases, NSW Health

So, even though, as Dr. Fauci points out, that vaccine which will be used this year is "essentially identical" to the vaccine being used in Australia, "An intelligent guess, therefore, is that the north will probably have a bad flu season." 

And, just like the composition of each year's vaccine, which must be decided six months before the start of the flu season (2), predicting what the flu will finally do is at best as an educated guess. Dr. Paul Offit, the chief of the division of infectious diseases at Children’s Hospital of Philadelphia, and a former American Council advisor concurs.

Preventing influenza infections is one of the most difficult tasks in medicine. Every year the virus mutates. Some years the virus is particularly aggressive; some years not. It's like predicting the stock market.

Dr. Paul Offit, the chief of the division of infectious diseases at Children’s Hospital of Philadelphia

What to do? As is the case frequently in medicine, there is no ideal drug or vaccine for a particular condition. So the risks of an imperfect treatment must be weighed against its benefits. With flu, this is a no-brainer. Even in years where the coverage (match of circulating strains and those in the vaccine) is terrible (3), I roll up my sleeve. Flu is a very serious disease (4) and the vaccine is very safe. Adverse effects, if any, are mild and transient. One serious adverse effect, Guillain-Barré syndrome (GBS) is estimated to occur in 1-2 people per million vaccinations.

There is the information. I hope you make the right decision.

Notes:

(1) H stands for hemagglutinin, a viral surface protein, which is responsible for binding the virus to the host cell and enabling it to fuse with the host cell membrane, allowing it to penetrate the cell. N stands for neuraminidase, a viral enzyme that is responsible for cleaving the virus from the membrane once it enters the cell. Both proteins are essential for replication of influenza virus. 

(2) Selecting the strains covered in each year's vaccine is a daunting task. Investigators must make an educated guess of which strains to include based on predominant strains circulating in Asia and Australia six months in advance since it takes that long to grow the vaccine in eggs. Sometimes the predominant strain in Asia will end up not being be the predominant strain in the US. Worse still, even when the circulating strains and those chosen for the vaccine may be a perfect match, the vaccine can still be ineffective. This is partly because the virus can mutate during that time, which renders the vaccine less effective, or even ineffective. 

(3) The 2014-5 season vaccine was very ineffective. It reduced illness by only 19%  far less than a "good" vaccine (50-60%). But 19% is still better than nothing.

(4) Flu kills between 3,300 and 49,000 people per year in the US. The average is about 36,000. For perspective, here are annual mortality figures for selected cancers;

• Breast - 40,000
• Prostate - 27,000
• Colon - 50,000
• Lung - 156,000

The New Science On Anxiety And Gut Health

“Gut health is so important! Great read.”

— Dr. Dale

From The New Science On Anxiety And Gut Health

While docs used to treat mental health conditions with a pill and a glass of water, the times are changing. Probiotics are arguably the new Prozac already—and now there’s a concrete case for combating anxiety with good bacteria, too.

In a new study conducted at the University of Cork in Ireland, researchers broke new ground in understanding the relationship between gut health and anxiety. While the microbiome-brain connection—AKA the link between digestive and mental health—has been established in other studies, this time they found a first-of-its-kind connection between gastrointestinal microbes and gene regulators in the brain (called microRNAs).

In the study, researchers discovered the mice living a germ-free life ended up having unusual amounts of anxiety.

“Gut microbes seem to influence miRNAs in the amygdala and the prefrontal cortex,” lead research Gerard Clarke said in a press release. “This is important because these miRNAs may affect physiological processes that are fundamental to the functioning of the central nervous system and in brain regions, such as the amygdala and prefrontal cortex, which are heavily implicated in anxiety and depression.”

In the study, researchers introduced gut bacteria to two groups of mice: One raised in a germ-free environment, and the other made up of mice raised in a normal environment. They discovered the mice living germ-free ended up having unusual amounts of anxiety, but they weren’t stuck with it: When they added the gut bacteria back in later on, they normalized the changes to the miRNAs, showing a healthy gut could be the answer to regulating the miRNAs.

Additional research still needs to be done, but this study is definitely a step in the right direction. If your probiotics seem to help keep your anxiety at a healthy level, keep doing what you’re doing: The little guys in your stomach are on your side.

HIV/AIDS and Aging Awareness Day - Learn more about HIV/AIDS

“HIV/AIDS and Aging Awareness Day is September 18th. Read this to learn more about HIV/AIDS.”

— Dr. Dale

From What Are HIV and AIDS?

About HIV & AIDS

HIV is a virus spread through certain body fluids that attacks the body’s immune system, specifically the CD4 cells, often called T cells. Over time, HIV can destroy so many of these cells that the body can’t fight off infections and disease. These special cells help the immune system fight off infections. Untreated, HIV reduces the number of CD4 cells (T cells) in the body. This damage to the immune system makes it harder and harder for the body to fight off infections and some other diseases. Opportunistic infections or cancers take advantage of a very weak immune system and signal that the person has AIDS. Learn more about the stages of HIV and how to know whether you’re infected.

What Is HIV?

HIV stands for human immunodeficiency virus. It is the virus that can lead to acquired immunodeficiency syndrome, or AIDS, if not treated. Unlike some other viruses, the human body can’t get rid of HIV completely, even with treatment. So once you get HIV, you have it for life.

HIV attacks the body’s immune system, specifically the CD4 cells (T cells), which help the immune system fight off infections. Untreated, HIV reduces the number of CD4 cells (T cells) in the body, making the person more likely to get other infections or infection-related cancers. Over time, HIV can destroy so many of these cells that the body can’t fight off infections and disease. These opportunistic infections or cancers take advantage of a very weak immune system and signal that the person has AIDS, the last stage of HIV infection.

No effective cure currently exists, but with proper medical care, HIV can be controlled. The medicine used to treat HIV is called antiretroviral therapy or ART. If taken the right way, every day, this medicine can dramatically prolong the lives of many people infected with HIV, keep them healthy, and greatly lower their chance of infecting others. Before the introduction of ART in the mid-1990s, people with HIV could progress to AIDS in just a few years. Today, someone diagnosed with HIV and treated before the disease is far advanced can live nearly as long as someone who does not have HIV.

What Is AIDS?

AIDS is the most severe phase of HIV infection. People with AIDS have such badly damaged immune systems that they get an increasing number of severe illnesses, called opportunistic infections.

What Are the Stages of HIV Infection?

Without treatment, HIV advances in stages, overwhelming your immune system and getting worse over time. The three stages of HIV infection are: (1) acute HIV infection, (2) clinical latency, and (3) AIDS (acquired immunodeficiency syndrome).

However, there’s good news: by using HIV medicines (called antiretroviral therapy or ART) consistently, you can prevent HIV from progressing to AIDS. ART helps control the virus so that you can live a longer, healthier life and greatly reduces the risk of transmitting HIV to others.

These are the three stages of HIV infection:

Acute HIV Infection Stage

Within 2 to 4 weeks after infection, many, but not all, people develop flu-like symptoms, often described as “the worst flu ever.” Symptoms can include fever, swollen glands, sore throat, rash, muscle and joint aches and pains, and headache. This is called “acute retroviral syndrome” (ARS) or “primary HIV infection,” and it’s the body’s natural response to the HIV infection. People who think that they may have been infected recently and are in the acute stage of HIV infection should seek medical care right away. Starting treatment at this stage can have significant benefits to your health.

During this early period of infection, large amounts of virus are being produced in your body. The virus uses CD4 cells to replicate and destroys them in the process. Because of this, your CD4 cells can fall rapidly. Eventually your immune response will begin to bring the level of virus in your body back down to a level called a viral set point, which is a relatively stable level of virus in your body. At this point, your CD4 count begins to increase, but it may not return to pre-infection levels. It may be particularly beneficial to your health to begin ART during this stage.

During the acute HIV infection stage, you are at very high risk of transmitting HIV to your sexual or needle-sharing partners because the levels of HIV in your blood stream are extremely high. For this reason, it is very important to take steps to reduce your risk of transmission.

Clinical Latency Stage

After the acute stage of HIV infection, the disease moves into a stage called the “clinical latency” stage. “Latency” means a period where a virus is living or developing in a person without producing symptoms. During the clinical latency stage, people who are infected with HIV experience no symptoms, or only mild ones. (This stage is sometimes called “asymptomatic HIV infection” or “chronic HIV infection.”)

During the clinical latency stage, the HIV virus continues to reproduce at very low levels, even if it cannot be detected with standard laboratory tests. If you take ART, you may live with clinical latency for decades and never progress to AIDS because treatment helps keep the virus in check. (Read more about HIV treatment.)

People in this symptom-free stage are still able to transmit HIV to others, The risk of transmission is greatly reduced by HIV transmission. In studies looking at the effects of HIV treatment on transmission, no new HIV infections have been linked to someone with very low or undetectable (suppressed) viral load.

For people who are not on ART, the clinical latency stage lasts an average of 10 years, but some people may progress through this stage faster. As the disease progressions, eventually your viral load will begin to rise and your CD4 count will begin to decline. As this happens, you may begin to have constitutional symptoms of HIV as the virus levels increase in your body before you develop AIDS.

AIDS

This is the stage of HIV infection that occurs when your immune system is badly damaged and you become vulnerable to opportunistic infections. When the number of your CD4 cells falls below 200 cells per cubic millimeter of blood (200 cells/mm3), you are considered to have progressed to AIDS. (In someone with a healthy immune system, CD4 counts are between 500 and 1,600 cells/mm3.) You are also considered to have progressed to AIDS if you develop one or more opportunistic illnesses, regardless of your CD4 count.

Without treatment, people who progress to AIDS typically survive about 3 years. Once you have a dangerous opportunistic illness, life-expectancy without treatment falls to about 1 year. ART can be helpful for people who have AIDS when diagnosed and can be lifesaving. Treatment is likely to benefit people with HIV no matter when it is started, but people who start ART soon after they get HIV experience more benefits from treatment than do people who start treatment after they have developed AIDS.

In the United States, most people with HIV do not develop AIDS because effective ART stops disease progression. People with HIV who are diagnosed early can have a life span that is about the same as someone like them who does not HIV.

People living with HIV may progress through these stages at different rates, depending on a variety of factors, including their genetic makeup, how healthy they were before they were infected, how much virus they were exposed to and its genetic characteristics, how soon after infection they are diagnosed and linked to care and treatment, whether they see their healthcare provider regularly and take their HIV medications as directed, and different health-related choices they make, such as decisions to eat a healthful diet, exercise, and not smoke.

Is There a Cure for HIV?

No effective cure currently exists for HIV. But with proper medical care, HIV can be controlled. Treatment for HIV is called antiretroviral therapy or ART. If taken the right way, every day, ART can dramatically prolong the lives of many people infected with HIV, keep them healthy, and greatly lower their chance of infecting others. Before the introduction of ART in the mid-1990s, people with HIV could progress to AIDS (the last stage of HIV infection) in a few years. Today, someone diagnosed with HIV and treated before the disease is far advanced can live nearly as long as someone who does not have HIV.

Learn about how to protect yourself, and get information tailored to meet your needs from CDC’s HIV Risk Reduction Tool (BETA).