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CDC: Autism Rate Up To 1 in 68 Kids, But Still No Why

A new CDC analysis of autism prevalence shows a nearly 30 percent jump in cases between 2008 and 2010: that means 1 out of every 68 eight-year-olds in the U.S. is diagnosed with the disorder.

But health officials still don’t agree on what’s driving the increase. Debate continues to rage over whether the increase in cases is due to changing definitions and greater awareness of autism spectrum disorders, or if it’s due to some environmental or other factor.

Karen Weintraub reports for USA Today:

…virtually every grade in every elementary school has at least one child with autism – a seemingly astonishing rise for a condition that was nearly unheard of a generation ago.

What’s still unknown is the driver of that increase. Many experts believe the rise is largely due to better awareness and diagnosis rather than a true increase in the number of children with the condition.

(Jesse Costa/WBUR)

(Jesse Costa/WBUR)

“We don’t know the extent those factors explain in terms of the increase, but we clearly know they do play a role,” said Coleen Boyle, director of the National Center on Birth Defects and Developmental Disabilities at the CDC. “Our system tells us what’s going on. It (only) gives us clues as to the why.”

The aging of parents is also known to be a factor; the chances of autism increase with the age of parents at conception.

“But that’s not the whole story is it?” said Robert Ring, chief science officer for Autism Speaks, a research and advocacy group. Whether something in the environment could be causing the uptick remains “the million-dollar question,” Ring said.

Despite their concern, experts said they were not surprised by the increase, because other data had suggested the numbers would continue to climb. In New Jersey, for instance, autism rates were 50% higher than in the rest of the nation in 2000, and they remained that much higher in 2010 – suggesting the national rates will continue to rise to catch up, said Walter Zahorodny, a psychologist who directs the New Jersey Autism Study. “To me it seems like autism prevalence can only get higher,” Continue reading

Study Finds Fivefold Increase In Alzheimer’s Deaths: Why It Matters

JAQ'S PhotoStorage/flickr

JAQ’S PhotoStorage/flickr

By Nell Lake
Guest contributor

Consider a hypothetical 70-year-old woman; she could be your mother, your sister, your wife. Call her Margaret. She’s becoming ever-more forgetful; one day she gets lost on her way home from the grocery store. A neurologist diagnoses Alzheimer’s.

Over the next five years, Margaret’s thinking continues to decline. She speaks less, confuses words, falls often. She needs a wheelchair, becomes incontinent. No longer able to manage her care, you move her to a nursing home. A year later, the disease has spread to the part of Margaret’s brain that controls swallowing; she has difficulty eating. Because of this she “aspirates” her food — bits of it enter her lungs, and Margaret develops pneumonia. Within weeks, her lungs stop working, and Margaret dies.

Margaret’s story is a difficult one, but common. It also illustrates a conundrum: Did Margaret die of pneumonia, or Alzheimer’s?

On some level, the answer doesn’t matter much: death is death. But as a matter of public health, the answer is deeply important: funding for medical research, new treatments and ultimately, someday, a cure, tends to flow toward the most widespread and deadly diseases. That’s why a new study out this week is getting so much attention; should its findings become widely accepted, they could substantially increase the pace and effectiveness of Alzheimer’s research in the U.S.

Massive Underreporting

The study, published Wednesday in the journal Neurology, confirmed what clinicians and researchers have long assumed: Alzheimer’s deaths have been greatly underreported.

The research found that 500,000 people die each year from Alzheimer’s — more than five times the number most recently reported by the CDC. That makes Alzheimer’s the third leading cause of death in the United States, after heart disease and cancer. Currently the CDC ranks Alzheimer’s sixth as a cause of mortality, with 84,000 deaths reported on death certificates.

The new report’s fuller accounting of Alzheimer’s deaths reinforces a basic but frequently overlooked fact: The illness is entirely fatal. A progressive brain disease that gradually impairs memory, reasoning and personality, Alzheimer’s eventually damages all brain functions, so that even walking, eating and breathing become impossible. Alzheimer’s kills because the brain is no longer able to keep the body alive. Continue reading

New Home Birth Data: Numbers Rise A Bit, Controversy Remains Unchanged

A new CDC analysis of trends in out-of-hospital births from 1990-2012 found that home births are on the rise — but only a tiny bit.

The federal agency reports that 1.36 percent of U.S. births occurred outside a hospital in 2012, up
from 1.26 percent in 2011. Those new numbers mark the highest level of non-hospital births since 1975, according to the CDC.

In terms of actual births, that means 53,635 births in the U.S. took place out of a hospital in 2012, including 35,184 home births and 15,577 birthing center births, the CDC says.

(Source: CDC)

(Source: CDC)

Here are some more findings from the CDC news release:

• In 2012, 1 in 49 births to non-Hispanic white women were out-of-hospital births;

•The percentage of out-of-hospital births was generally higher in the northwestern United States and lower in the southeastern United States;

•Out-of-hospital births generally had a lower risk profile than hospital births.

Continue reading

The Good News, Bad News Story On Measles

Back of female with measles/ Wellcome Library, London. Wellcome Images/flickr

Back of female with measles/ Wellcome Library, London. Wellcome Images/flickr

By Alexandra Morris
CommonHealth Intern

Lately, when you hear about measles in the news, the reports tend to be grim: outbreaks in 2011 and 2013 in the U.S., parents who are choosing not to vaccinate their children for religious or philosophical reasons. But a new report from the CDC this week paints a bigger – and far more heartening – picture: from 2000 to 2012, 13.8 million deaths were prevented through measles immunizations globally. In other words, a population roughly the size of New England is still alive thanks to the measles vaccine.

Deaths from measles have dropped 78% since 2000. “These figures represent historic lows for estimated measles deaths globally,” said James Goodson, a co-author of the CDC report published in this week’s Morbidity and Mortality Weekly Report.

Since 2000, the Measles and Rubella Initiative – a partnership between various agencies including the CDC and the World Health Organization – has provided over a billion doses of measles vaccinations worldwide.

Measles was eliminated in the U.S. in 2000, but there have been a couple of recent spikes in cases. Just last year, there were three times as many measles infections in the U.S. than in previous years. In raw numbers, that translates to 189 cases, according to the CDC. While that doesn’t seem like a lot, such a highly contagious disease can spread rapidly, especially among people who haven’t been vaccinated.

Countries around the world are also aiming to eliminate measles by 2020 or earlier. Europe, for example, set a goal of measles elimination by 2015. But it doesn’t look like they’re on track to meet that goal, said Goodson. That may be due in part to parents’ fears about the possibility of vaccine side effects.

In 1998, a British medical journal issued a report suggesting the measles vaccine was linked to autism cases, which led to a sharp decline in vaccinations. Although the report was discredited, and later retracted by the journal, parent and anti-vaccine groups continue to fight against routine immunizations.

Misinformation is a major threat to vaccine efforts, say public health officials. Continue reading

CDC: Millions Acquire Antibiotic-Resistant Infections, Thousands Die Annually

The CDC reports today that more than two million people a year in the U.S. get infections that are resistant to antibiotics and at least 23,000 people die as a result.

In a new report called Antibiotic Resistance Threats in the United States, 2013, the public health agency ranks the antibiotic-resistant germs most threatening to human health. Here’s more from the CDC website:

The threats are ranked in categories: urgent, serious, and concerning.
Threats were assessed according to seven factors associated with resistant infections: health impact, economic impact, how common the infection is, a 10-year projection of how common it could become, how easily it spreads, availability of effective antibiotics, and barriers to prevention. Infections classified as urgent threats include carbapenem-resistant Enterobacteriaceae (CRE), drug-resistant gonorrhea, and Clostridium difficile, a serious diarrheal infection usually associated with antibiotic use. C. difficile causes about 250,000 hospitalizations and at least 14,000 deaths every year in the United States.

“Antibiotic resistance is rising for many different pathogens that are threats to health,” said CDC Director Tom Frieden, M.D., M.P.H. “If we don’t act now, our medicine cabinet will be empty and we won’t have the antibiotics we need to save lives.”

In addition to the toll on human life, antibiotic-resistant infections add considerable and avoidable costs to the already overburdened U.S. health care system. Studies have estimated that, in the United States, antibiotic resistance adds $20 billion in excess direct health care costs, with additional costs to society for lost productivity as high as $35 billion a year. The use of antibiotics is the single most important factor leading to antibiotic resistance. Up to 50 percent of all the antibiotics prescribed for people are not needed or are not prescribed appropriately. Continue reading

Despite Mounting Evidence, High School Girls Keep Tanning

(valerieyermal/flickr)

You’re surely aware of all of the information out there clearly explaining why tanning salons are absolutely, unquestionably not a good idea?

Evidently, young America has yet to get the memo.

As a new report from JAMA Internal Medicine found:

Among non-Hispanic white female high school students, 29.3% engaged in indoor tanning and 16.7% engaged in frequent indoor tanning during the previous 12 months. The prevalence of indoor tanning and frequent indoor tanning increased with age.

These numbers  — about 1/3 of high schoolers tanning within the past year — are surprisingly static. A study done by the CDC in 2010 also found about a third of young white women reported indoor tanning.

What’s going amiss? I talked to Emily Colson, a high school senior in South Carolina whose experience closely mirrors the study’s findings. She first started using tanning beds as a freshman, relying on them for occasions with high expectations, like prom and the first week of summer. “I don’t like being pale or being pasty – I think I look a lot better when I’m tanner,” she said. Continue reading

New CDC Estimate: 300K Americans Diagnosed With Lyme Disease Each Year

Tick

If you follow Lyme disease at all, you know that there’s no question that the official prevalence figures fail to capture the true extent of the toll those nasty little disease-spreading deer ticks take. The only question is just how far the official figures fall short of reality.

WBUR’s Lyme Disease series last summer cited these official figures for Massachusetts: 2-4,000 confirmed cases each year. But everyone knows those numbers are laughably low. Dr. Catherine Brown of the Massachusetts Department of Public Health said a more realistic figure might be the 12-14,000 positive lab tests for Lyme disease reported statewide each year. But that’s clearly still low. A leading tick expert estimated that in much of Massachusetts, about 1 percent of the population contracts Lyme each year.

Now, at a major conference on Lyme disease and other tick-borne illnesses under way in Boston, federal health authorities have just released their own more realistic estimate, and it’s about ten-fold their old one. From the CDC press release:

Preliminary estimates released by the Centers for Disease Control and Prevention indicate that the number of Americans diagnosed with Lyme disease each year is around 300,000. The preliminary estimates were presented Sunday night in Boston at the 2013 International Conference on Lyme Borreliosis and Other Tick-Borne Diseases.

This early estimate is based on findings from three ongoing CDC studies that use different methods, but all aim to define the approximate number of people diagnosed with Lyme disease each year. The first project analyzes medical claims information for approximately 22 million insured people annually for six years, the second project is based on a survey of clinical laboratories and the third project analyzes self-reported Lyme disease cases from a survey of the general public.

Each year, more than 30,000 cases of Lyme disease are reported to CDC, making it the most commonly reported tick-borne illness in the United States. The new estimate suggests that the total number of people diagnosed with Lyme disease is roughly 10 times higher than the yearly reported number. This new estimate supports studies published in the 1990s indicating that the true number of cases is between 3- and 12-fold higher than the number of reported cases. Continue reading

Worry About New ‘World Threat’ Virus? Specialist: We Just Don’t Know

You may have seen this headline last week: “World Health Organization says new virus may be ‘threat to entire world.‘” And if you’re like me, you may have been surprised by your own ho-hum reaction. Is this a crying-wolf situation? Have we been warned about too many potentially scary viruses over the last few years? Or are we just getting more used to living with viral uncertainty? Here, Dr. Paul Sax, clinical director of the Division of Infectious Diseases at Brigham and Women’s Hospital, writes about his own reaction to this latest outbreak in the face of insufficient information.

By Dr. Paul E. Sax
Guest contributor

From one of my close friends — a non-MD — comes this alarming video.

And here’s his email:

Concerned? Terrified? I bet your department is buzzing about this.

Um, not quite — especially since, among the 49 cases in the world (apparently there are five more than the WHO reported), exactly zero have occurred thus far in the United States. As of May 29, 2013, it hasn’t even cracked the front page of the CDC site.

Is MERS-CoV — short for Middle East Respiratory Syndrome Coronavirus — potentially of great concern? Of course. The WHO response seems right, especially with the parallels to SARS.

Coronoviruses (these are not the new Middle East virus) are a group of viruses that have a halo, or crown-like (corona) appearance when viewed under an electron microscope. (Wikimedia Commons)

Coronoviruses (this image is not of the new Middle East virus) are a group of viruses that have a halo, or crown-like (corona) appearance when viewed under an electron microscope. (Wikimedia Commons)

But do we garden-variety infectious disease specialists know how serious it will be on a global basis? Of course not. As with the first SARS cases, the first anthrax cases, the first West Nile cases, the first hantavirus cases, even the first AIDS cases — we really don’t have enough points on the graph yet to make any sort of confident predictions.

And from a practical perspective, the clinical unfamiliarity doesn’t help. If someone walked into our emergency room tomorrow with fever, cough, and respiratory symptoms, would we know how to distinguish MERS-CoV — from the hundreds (OK, thousands) of other causes of similar illnesses?

Initially, not a chance. The denominator of people with these complaints is just too gargantuan. It will probably take someone with a particularly severe respiratory illness, along with the appropriate exposure (“He just returned from a 10-day business trip to Riyadh”) for an astute clinician to make the connection.

So how should we infectious disease doctors, who are supposed to know everything, respond to these emails in the interim? Continue reading

More On Google Flu Trends: Brilliant Predictor Or Cautionary Tale

In case you missed this excellent post on whether ‘Google Flu Trends’ is prescient or wrong, you’ve got a second chance to hear the details today on Radio Boston.

The segment features MIT computer science graduate student Keith Winstein (and my former colleague at The Wall Street Journal) exploring what might account for the dramatic divergence between Google’s flu data and the official CDC flu numbers. “This could be a cautionary tale about the perils of relying on these “Big Data” predictive models in situations where accuracy is important,” Winstein said in an interview with CommonHealth.

Here are some more of his thoughts:

The issue that’s interesting from the computer science perspective is this: Google Flu Trends launched to much fanfare in 2008 — it was even on the front page of the New York Times — with this idea that, as the head of Google.org said at the time, they could out-perform the CDC’s very expensive surveillance system, just by looking at the words that people were Googling for and running them through some statistical tools.

It’s a provocative claim and if true, it bodes well for being able to track all kinds of things that might be relevant to public health. Google has since launched Flu Trends sites for countries around the world, and a dengue fever site.

So this is an interesting idea, that you could do public health surveillance and out-perform the public health authorities [which use lab tests and reports from ‘sentinel’ medical sites] just by looking at what people were searching for.

‘It is often a problem with computers that they only tell us things we already know.’
Google was very clear that it wouldn’t replace the CDC, but they have said they would out-perform the CDC. And because they’re about 10 days earlier than the CDC, they might be able to save lives by directing anti-viral drugs and vaccines to afflicted regions.

And their initial paper in the journal Nature said the Google Flu Trends predictions were 97% accurate…

That was astounding. However, it is often a problem with computers that they only tell us things we already know. When you give a computer something unexpected, it does not handle it as well as a person would.

Shortly after that report of 97% accuracy, we had that unexpected swine flu, which was a different time of year from the normal flu season, and it was different symptoms from normal, and so Google’s site didn’t work very well.

[Carey asks: And the accuracy went down to 20-something percent?]

To a 29 percent correlation, and it had just been 97 percent. So it was not accurate. Continue reading

Is ‘Google Flu Trends’ Prescient Or Wrong?

flu graph

Google in blue, CDC in red. Note the dramatic divergence toward 2013. (Keith Winstein, MIT)

Has Google’s much-celebrated flu estimator, Google Flu Trends, gotten a bit, shall we say, over-enthusiastic?

Last week, a friend commented to Keith Winstein, an MIT computer science graduate student and former health care reporter at The Wall Street Journal: “Whoa. This flu season seems to be the worst ever. Check out Google Flu Trends.”

Hmmm, Winstein responded. When he checked, he saw that the official CDC numbers showed the flu getting worse, but not nearly at Google’s level. (See the graph above.) The dramatic divergence between the Google data and the official CDC numbers struck him: Was Google, he wondered, prescient or wrong?

He began to explore — as much as a heavy grad-student schedule allows — and shares his thoughts here. Our conversation, lightly edited:

I accept the caveat that these predictive algorithms are not your speciality, but still, from highly informed, casual observation, what are you seeing, in a highly preliminary sort of way?

Well, I’m certainly not an expert on the flu. The issue that’s interesting from the computer science perspective is this: Google Flu Trends launched to much fanfare in 2008 — it was even on the front page of the New York Times — with this idea that, as the head of Google.org said at the time, they could out-perform the CDC’s very expensive surveillance system, just by looking at the words that people were Googling for and running them through some statistical tools.

It’s a provocative claim and if true, it bodes well for being able to track all kinds of things that might be relevant to public health. Google has since launched Flu Trends sites for countries around the world, and a dengue fever site.

So this is an interesting idea, that you could do public health surveillance and out-perform the public health authorities [which use lab tests and reports from ‘sentinel’ medical sites] just by looking at what people were searching for.

‘It is often a problem with computers that they only tell us things we already know.’

Google was very clear that it wouldn’t replace the CDC, but they have said they would out-perform the CDC. And because they’re about 10 days earlier than the CDC, they might be able to save lives by directing anti-viral drugs and vaccines to afflicted regions.

And their initial paper in the journal Nature said the Google Flu Trends predictions were 97% accurate…

That was astounding. However, it is often a problem with computers that they only tell us things we already know. When you give a computer something unexpected, it does not handle it as well as a person would.

Continue reading