Stories tagged disease

May
08
2008

Fighting AIDS in Africa: Many people are at risk, but officials disagree over the best approach.
Fighting AIDS in Africa: Many people are at risk, but officials disagree over the best approach.Courtesy Stig Nygaard

Two years ago, an article in the journal Science noted that rates of AIDS infection were falling in Zimbabwe, south east Africa, thanks to the “ABC” program. “ABC” stands for “Abstinence, Be faithful, use Condoms” – three things that help prevent the spread of sexually-transmitted diseases. Other countries using the ABC approach, including Uganda and Kenya, also report success in stemming the tide of AIDS.

The report was in the news again lately as Congress debates funding for the President's Emergency Plan for AIDS Relief (PEPFAR). Rep. Chris Smith of NJ cited this and other studies as evidence of the program effectiveness. (An argument for continuing the funding can be found here. )

The program is controversial, however, because it adds a moral dimension to medical treatment. Many aid workers don’t want to be in the position of telling people how to live, or imposing a particular view of right and wrong behavior on another culture. They would rather just treat the disease. OTOH, this particular disease spreads through a particular behavior. Programs that rely exclusively on condoms without any behavioral component have had little success against the AIDS epidemic.

Some people see this controversy as playing politics with a world health crisis. But others take it very seriously. In 2005, Brazil refused to accept US funds for their AIDS program because it came with the requirement that workers try to discourage prostitution. Many aid groups argue that such a provision hurts their ability to reach the people who need help the most. The government argues that discouraging prostitution and sex trafficking makes all kinds of sense when combating an STD.

It would be good to get this sorted out soon, since there is no vaccine against AIDS, and some scientists believe it may be impossible to ever make one.

What do you think? Should aid workers try to combat disease by changing people’s behavior? Or should they just stick to medicine? And should government funding come with such restrictions? Leave us a comment.

Jan
18
2008

Aedes aegypti mosquito
Aedes aegypti mosquitoCourtesy Photo courtesy Centers for Disease Control and Prevention
A re-emerging threat
Dengue fever is making a come back in South America and some fear it could become a problem again in the US as well. The year 2007 was an epidemic record-breaking year there was an 11% increase in reported dengue cases when comparing 2006 to 2007. Some even fear it could be spreading to the US. There was a recent article in the Los Angeles Times about it reappearing in the US.
What is dengue fever?
Dengue is a viral infection spread by the predominantly urban species Aedes aegypti mosquitoes. In recent years dengue has become a major international public health concern. Dengue is found in tropical and sub-tropical regions around the world, predominantly in urban and semi-urban areas.
Dengue fever is a severe, flu-like illness that affects infants, young children and adults, but seldom causes death. Dengue haemorrhagic fever is a potentially deadly complication that is characterized by high fever, haemorrhagic phenomena--often with enlargement of the liver--and in severe cases, circulatory failure.
Why is dengue making a come back?
Potential reasons include climate influences like global warming, El Niño / Southern Oscillation and La Niña, both of which influence the intensity and duration of the rainy seasons and hurricanes or induce intense droughts and damage to biodiversity. Another potential cause is population growth and increased opportunities for mosquitoes to breed.
On the other hand, micro factors exist that are dependent on the agent (virus) and the vector (mosquito)—which at times exhibits a growing resistance to insecticides—and the host, all of which closely influence the manifestation of the disease and its more serious forms.

Jan
12
2008

Brain scan of an Alzheimer’s patient
Brain scan of an Alzheimer’s patientCourtesy NIH/National Institute on Aging

Doctors in California have developed a treatment for Alzheimer’s disease, in which patients show tremendous improvement within minutes.

Alzheimer’s is a disease of the brain which can severely impair memory, thinking and behavior. The researchers noticed that Alzheimer’s patients have very high levels of a protein called TNF, which is known to regulate brain activity. The treatment involves injecting an anti-TNF drug into the patient’s spinal fluid. The drug, Etanercept, has already been approved by the FDA for treatment of other diseases. The study involved only a small number of patients, but the strong positive results of this early test give hope that an effective treatment for Alzheimer’s could be on the horizon.

NOTE: As always when we discuss medical treatment on Science Buzz, it is important to point out – we are not doctors. We cannot give medical advice, nor should you take medical advice from anyone over the Internet. If you have questions about this treatment, you need to consult your physician.

Jan
12
2008

So fragile, so vulnerable -- so what do you do?: How would you allocate funds to protect the Earth from disaster?
So fragile, so vulnerable -- so what do you do?: How would you allocate funds to protect the Earth from disaster?Courtesy NASA

The Lifeboat Foundation, a nonprofit organization dedicated to finding solutions to global challenges, has an interesting poll on its blog. Let’s say you had an extra $100 million lying around, and you could spend it to protect the Earth and all its people from the following threats:

  • Deadly diseases
  • Global warming
  • Invasion from outer space
  • Abusive governments
  • Nanotechnology run amok
  • Nuclear holocaust
  • Asteroid collision
  • Intelligent computers run amok
  • Simulation shut down
  • Other

How would you distribute the $100 million? You might think all of these issues are important, but you’ve only got so much money. How would you spend it? (You can go to the Lifeboat blog and cast your vote, and see how other people have voted.)

Actually, a similar survey has already been run by Danish political scientist Bjorn Lomborg. He runs the Copenhagen Consensus, a program which invites world leaders to prioritize their efforts based on what actions would produce the greatest benefits. They found that every dollar spent on health issues, such as AIDS, malnutrition and malaria, produced up to $40 worth of benefits, while money spent on other worthy causes often generated much less.

As for me, I’d also put most of my money on deadly diseases – this is something we know is real. I’d probably also put a chunk on “other” for environmental protection – pollution, deforestation, species loss.

This is not to dismiss all of the other threats. I certainly worry about some crackpot getting a hold of nuclear weapons. But full-scale nuclear holocaust seems a lot less likely now than it did back during the Cold War. Abusive governments? A local problem, to be sure, but not one likely to threaten the planet and all life on it.

The others seem rather far-fetched to me. Global warming? My skepticism over the threat this poses is well-documented elsewhere on this blog, though certainly others disagree with me. Asteroid collision? Happens once every 100 million years or so; killer germs emerge once a generation. Invasion from outer space? Get real – if interstellar travel were possible, wouldn’t the space men be here by now? Nanotechnology turning everything into gray goo? A casual familiarity with nano shows that such fears are vastly overrated. Artificial intelligence ruling the world? They’ve been promising AI since the early ‘60s – I’m still waiting.

My favorite, though, is “Simulation shut down.” Basically, this means that nothing in this world is real – you, I, and everything on Earth are just part of a massive virtual game run on a gigantic computer operated by some intelligent being in another dimension, and we need to prevent him/her/it from turning the computer off. While this would certainly explain a few anomalies I’ve noticed in the Universe (I mean, come on, penguins?), epistemologically, there is no way we could possibly know whether or not this was true. And even if it was, how could our $100 million virtual dollars have any effect on the being running the program?

What about you? How would you spend a theoretical $100 million to save the Earth? Leave a note in the comments.

Jan
10
2008

Hookworms in the lining of the intestines: All together now: "ewwwwwwwwwwww."
Hookworms in the lining of the intestines: All together now: "ewwwwwwwwwwww."Courtesy Centers for Disease Control and Prevention

Cleanliness is next to godliness, but is it possible to have too much of a good thing? For several decades, immunological diseases -- such as hay fever, asthma, diabetes and multiple sclerosis – have been increasing in developed countries, but are uncommon in many undeveloped regions. Medical researcher Joel Weinstock theorizes that modern life is too clean – by scrupulously avoiding dirt, bugs and germs, our immune systems don’t develop properly, leading to the diseases listed above. Weinstock goes so far as to speculate that exposure to hookworm, pinworm, and other intestinal parasites may have been the trigger necessary for developing a healthy immune system. As these parasites have been eradicated, immunological diseases have skyrocketed.

The theory is currently being tested in the lab. Weinstock doesn’t advocate the return of worm infestations. But he does think that getting your hands dirty once in a while can help keep your body in balance.

A new vaccine designed to fight AIDS has failed to show positive results during its first human tests. Researchers hope to learn what went wrong, and use that to make better vaccines in the future.

Jan
08
2008

An alternate theory holds that dinosaurs died of embarrassment: A Fredrogersaurus, obviously wishing he were dead, extinct, or just anywhere but here.
An alternate theory holds that dinosaurs died of embarrassment: A Fredrogersaurus, obviously wishing he were dead, extinct, or just anywhere but here.Courtesy Elston

Biting insects spread all kinds of diseases. (You can learn all about this in the Science Museum’s newest exhibit, Disease Detectives.) Now a scientists thinks they may have also helped kill off the dinosaurs. George Poinar, a professor of zoology at Oregon State University, notes that many insects from dinosaur times have been preserved in amber. Many of them carry microbes that can cause malaria, dysentery and other illnesses. He speculates that these illnesses could have been the major cause of the dinosaurs’ long, slow demise. The asteroid impact / volcanic activity / climate change simply finished them off.

Poinar and his wife Roberta have published a book, What Bugged The Dinosaurs? Insects, Disease And Death In The Cretaceous. In it they also note that, late in the dinosaur era, flowering plants spread rapidly, helped along by newly-evolved insect pollinators. This sudden change in available food may have also played a hand in the dinos’ extinction.

Nov
27
2007

Would have cancer killed Lincoln?: An author/physician theorizes that Abraham Lincoln would have soon died from a rare form of cancer if he had not been assassinated at Ford's Theater in 1865.
Would have cancer killed Lincoln?: An author/physician theorizes that Abraham Lincoln would have soon died from a rare form of cancer if he had not been assassinated at Ford's Theater in 1865.Courtesy Civics Online
I just finished reading an incredible book about Abraham Lincoln – Team of Rivals: The Political Genius of Abraham Lincoln -- by Doris Kearns Godwin. Of course, it ends with his assassination at Ford’s Theater right after the end of the Civil War.

Much to my surprise today, I come across a headline that at the time of his death, Lincoln may have only had about six months to live due to the effects of a rare type of cancer. Doctor/author John G. Sotos makes the case for Lincoln’s cancer diagnosis in an upcoming book.

One thing that struck me in Team of Rivals, which is written based on thousands of letters and diaries written by Lincoln’s associates during the time he was alive, was that most were first impressed and/or put off by his unusual appearance. Sotos theorizes that those appearances were related to Lincoln’s cancer.

Sotos thinks Lincoln suffered from MEN 2B, a genetic form of cancer that can account for unusual height along with unusual facial features – lumps of nervous tissue on the eyelids, tongue and lips. Sotos also thinks one of Lincoln’s sons died from the same type of cancer

And CSI-type techniques may come into play to see if Sotos is right. A small sampling of DNA is all that ‘s needed to check the condition of chromosome 10 of Lincoln’s genetic code to see if it shows signs of MEN 2B. Samples of his DNA can be collected from any of the many blood-stained fabrics that have been preserved from Lincoln’s death, or from the eight skull fragments that were preserved from the president’s autopsy.

If it is determined that Lincoln had MEN 2B, he’d be the earliest recorded case of that type of cancer. But as news of this theory has spread, there are already other members of the medical community saying that it isn’t possible.

What do you think? Should efforts be made to test some of Lincoln’s remains for MEN 2B? Or should we leave the remains alone and keep it a mystery? Share your thoughts here with other Science Buzz readers.

If you want to learn more about this, here’s the link to an extensive Washington Post article on the topic.

Nov
12
2007


People who are overweight stand a greater risk of dying from some diseases, but not for othersCourtesy Roger Cullman

Pretty bad. People who are overweight are more likely to die from diabetes and kidney failure than the general population. And people who are obese are more likely to die from heart disease and certain types of cancer.

These common-sense truths were reconfirmed last week by a report from the Centers for Disease Control, which analyzed decades of data from 39,000 Americans. However, the news was not all bad. For instance, obese people had the same overall mortality rate from cancer as the population as a whole. Which means that while they were at greater risk of dying from cancers that attack fatty tissues (including the breast, uterus, ovaries, kidneys, colon, throat and pancreas), they were actually less likely to die from other forms of cancer.

For folks who are overweight but not obese, the picture is even more complicated. Neither cancer nor heart disease killed this group at higher-than-average rates. In fact, researchers found lower mortality in this group for all other causes of death, including infectious diseases and accidents.

The researchers aren’t sure why this should be. One theory is that carrying a little extra fat – but not too much – gives the bodies the energy reserves it needs to fight off illness.

Another possibility is raised by the way the study defined “overweight” and “obese.” They did not measure the patients’ body fat directly, but rather used a mathematical calculation known as the Body Mass Index or BMI. This widely-used tool gives doctors a rough estimate of a person’s body fat – a number over 25 classifies a person as “overweight.” A BMI 30 or higher qualifies as “obese.”

The trouble is, BMI basically divides weight by height (with a couple other calculations thrown in for fun). The greater the weight, the higher the BMI for a given height. The problem is, people can add weight as fat, or they can add weight as muscle. Somebody who exercises a lot may be strong, healthy… and have a BMI that qualifies as overweight.

If that’s the case, then that would explain why the “overweight” group fights off disease and injury so well. Which is good news if you’re fit, but not so good news if you’re flabby.

Jul
27
2007

Staphylococcus aureus: There are some other photos of staph out there, but they all seem to involve a ton of pus.     (Photo by Estherase on flickr.com)
Staphylococcus aureus: There are some other photos of staph out there, but they all seem to involve a ton of pus. (Photo by Estherase on flickr.com)Courtesy Esther Simpson
Hand washing, nose picking, good hygiene, we all know about this stuff right? Do it, do it in the sanitary privacy of your bathroom, and do it, respectively. Dirty hands spread germs, and germs spread infections – we know this, and, consequently, are as clean as a nation of whistles. Or are we?

I recently catalogued ten everyday and seemingly harmless activities that I do, and then researched their hygienic ups and downs. I urge you to follow along, see which activities you do, and then tally up your hygiene score. I think you might be surprised…

1) Put dirty laundry in the washing machine.
2) Prepare a ham sandwich.
3) Give/receive a high-five.
4) Turn on a light switch.
5) Wash your hands.
6) Clean the cat box using only your fingers.
7) Touch a friend’s face.
8) Pet the dog.
9) Hold hands with a stranger.
10) Become hospitalized.

Okay. Now, being honest, figure out your score using this key:
1) –3, 2) –1, 3) –6, 4) –5, 5) +10, 6) –15, 7) –9, 8) –4, 9) –11, 10) –31.

And, remember, if you’ve washed your hands more than once, you get points for each time. Also, if you have, say, cleaned more than one cat box with just your fingers, take away fifteen points for each time.

So… how did you score? Uh huh, I thought so.

The score for the last item, becoming hospitalized, may be something of a surprise to you. However, a recent article in The New York Times has highlighted the huge difference that increased sanitary conditions makes in cutting infection rates. Simple things like more frequent hand washing, glove wearing, and better isolating patients known to carry certain pathogens has cut infection rates in hospitals as much as 78 percent.

It seems obvious enough, although some hospital administrators are hesitant to commit to change, fearing the increased costs associated with some procedures, and citing the fact that isolated patients often receive less attention from hospital staff, and are more likely to suffer from falls, bedsores, and increased stress.

Dealing with infections acquired in the hospital, on the other hand, can be dangerous and extremely expensive. One of the main culprits is methicillin-resistant Staphylococcus aureus, or MRSA. MRSA can be carried into hospitals by patients who demonstrate no symptoms, and can be passed by unwashed hands. If MRSA gets into a wound, it can cause anything from a painful sore to a fatal infection. By screening patients as they enter care, though, MRSA has been all but eliminated in countries like The Netherlands and Finland. Some states in the US are required to test certain high-risk patients for bacterium like MRSA, but very few hospitals screen all incoming patients.

Should the government require hospitals to screen all patients for MRSA? It’s not cheap, but it would save lives and probably money in the long run.
And could you possible think of a better way to clean the litter box than my tried-and-true bare hands method? Honestly?