Stories tagged infectious 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.

May
04
2008

China hopes to do the right thing

With the upcoming Olympics, China is in the spotlight. The Chinese Health Ministry, scrambling to fend off cover-up allegations, issued a nationwide alert Saturday over a virus that has killed 24 children and sickened more than 4,000 others.

Enterovirus-71 can be deadly

In milder cases, EV71 can cause cold like symptoms, diarrhea and sores on the hands, feet and mouth. But more severe cases can cause fluid to accumulate on the brain, resulting in polio-like paralysis and death (the journal Genetic Vaccines and Therapy). Public health officials expect the number of cases to peak in June or July. There is no effective antiviral treatment for severe EV71 infections, and no vaccine is available. This disease also has broken out in Hong Kong, Taiwan, Singapore and Vietnam, although no deaths have been reported there.

Cover your coughs and wash your hands

The viruses mainly strike children aged 10 and younger and is easily spread by sneezing or coughing. A public awareness campaign is ongoing, stressing the need for good personal hygiene, mostly by hand washing.

Sources: CNN and Los Angeles Times

If you are interested in learning more about cholera go to Science Museum of Minnesota's Disease Detectives website and explore cholera and four other important diseases through time. Cholera is also highlighted in a New-York Historical Society exhibition called PLAGUE in GOTHAM! Cholera in Nineteenth-Century New York. Click here to read an article about the exhibition in the New York Times.

The government began an unprecedented effort Friday to give vaccine critics a say in shaping how the nation researches safety questions surrounding immunizations.

A government-appointed working group is charged with picking the most important safety questions for the Centers for Disease Control and Prevention to research over the next five years. (Wired News)

Apr
08
2008

Don't touch my blood buddy: Alligator blood has been found to be high in certain peptides that are great at killing viruses, including HIV.
Don't touch my blood buddy: Alligator blood has been found to be high in certain peptides that are great at killing viruses, including HIV.Courtesy Bill Swindaman
Have you ever wondered why you never see alligators in the waiting room at the clinic?

For one thing, alligators have really bad medical insurance. But the bigger reason they stay so healthy is in their blood. New research has shown that alligator blood can kill off 23 different strains of bacteria. In effect, the gators have antibiotics in their blood.

Researchers started looking into alligator blood after noticing that the creatures rarely get infections despite all the wounds they suffer in their violent lives.

Why does any of this matter to us? The discovery could have huge impacts for our health. For one thing, experiments have shown the alligator blood is able to destroy much of HIV, the virus that leads to AIDS.

More specifically, alligator blood (and the blood of many other reptiles) is high in peptides, which are fragments of proteins). Learning more about these peptides could lead to the creation of medicines we’d be able to use to fight off strong viruses like HIV.

The full details are available at this link.

Don’t worry. You won’t be getting any transfusions of alligator blood the next time you’re at the hospital. Researchers estimate that pills or creams with the peptides that are also present in alligator blood might be ready for the human marketplace within the next seven years.

Apr
07
2008

Measles rash: This young boy has a 3 day old rash caused by the measles virus.
Measles rash: This young boy has a 3 day old rash caused by the measles virus.Courtesy CDC PHIL #1152

Recently, twelve people were diagnosed with measles in San Diego, another nine in Pima County Arizona. In Salzburg, Austria 180 people have been infected during a recent outbreak. Thankfully there haven’t been any deaths from these latest outbreaks.

People in Nigeria’s northern Katsina state have not been as lucky. At the moment they are facing a measles epidemic which has killed nearly two hundred children in the past three months, and infected thousands.

What’s going on?
It seams that parents, for a variety of reasons, are fearful of giving their children vaccinations. For nearly everyone, the measles vaccination is safe and effective and if you want more information about the vaccine click here. Measles outbreaks aren’t very common in the U.S., fewer than 100 per year. But in the pre-vaccine era, 3-4 million measles cases occurred every year in the US. This resulted in approximately 450 deaths, 28,000 hospitalizations and 1,000 children with chronic disabilities from measles encephalitis each year. These two outbreaks in the US serve as a reminder that unvaccinated people remain at risk for measles and that measles spreads rapidly without proper controls.

According to the WHO, around the world measles still kills 250,000 people each year. Most of these deaths occur in undeveloped nations where people don’t have access to vaccinations and healthcare. But it appears the problem in both Austria and Nigeria are unvaccinated children. In Nigeria many parents are afraid to vaccinate as reported in the VOA:

Katsina state's director of disease control, Halliru Idris, tells VOA that the outbreak is mostly affecting young people who have not been immunized. "I can tell you that over 95 percent of all the children that have measles are those whose parents have not allowed them to receive immunization," he said.
A handful of radical Islamic clerics instigated a boycott of infant vaccinations in northern Nigeria in 2003 and 2004, alleging that immunization was a western ploy to render Muslim girls infertile. Though the dispute has been resolved, parents still tend to avoid immunization.

In Austria officials fear that school administrators at the private school where the outbreak began advised parents against vaccinating their students. An investigation is ongoing.

So what should we do?
In Iowa the public health response to one imported measles case cost approximately $150,000. Should parents who choose not to vaccinate their children be responsible for these expenses? How do we balance personal choice and the good of the community?

New research published in Science reported bacteria can survive by eating antibiotics as a food source. This finding goes a step further than resistance. For a good summary read a blog on The Scientist website.

Have you ever wondered what antibiotic resistance really means? And who is resistant to those drugs? For a very good explanation read the blog entry Drug Resistance, Explained in the New York Times. I enjoyed the History of Medicine at the end too.

Did you find this explanation helpful? Did you learn anything that surprised you?

Mar
30
2008

An infected corpse emerges from the permafrost: a grisly sight.
An infected corpse emerges from the permafrost: a grisly sight.Courtesy Antony Pranata
For those of us requiring a refresher, smallpox is an infection caused by the viruses variola major and variola minor, and is spread by coughing, sneezing, and transmission of bodily fluids. Extremely virulent, it has been found that smallpox infection can result from the inhalation of fewer than 10 viral particles. About one third of the people who contract v. major die, and those who survive often suffer from scarring, limb deformities, and blindness. Over the course of the 20th century alone, it is estimated that smallpox was responsible for at least 300 million deaths (possibly as many as 500 million) across the world.

Since as early as 1000 BC, people have attempted to combat the virus through inoculation, initially though methods like rubbing smallpox pus into skin lesions, or by inhaling ground up smallpox scabs (don’t judge—who here hasn’t snorted a scab or two in their day?). These techniques, called “variolation”, did in fact greatly reduce the mortality rate of those infected with smallpox, but it wasn’t until almost 1800 before the first true smallpox vaccination was created. Thanks to successful vaccination campaigns since then, in 1979 smallpox was announced to be, well, gone—it is the only human infectious disease that has been completely eradicated from nature.

So now we can go about our lives, playing Frisbee, painting by numbers, handling dead bodies, and squeezing pustules, with no fear of this horrible disease.

Though natural infections no longer occur, the smallpox virus itself is kind of a tenacious little creature, occasionally surviving for considerable lengths of time outside of a living body—a British construction worker, for instance, contracted the disease while demolishing a building that formerly housed smallpox victims, and Dutch researchers have found a living virus in a 13-year-old scab. The virus also tends to persist quite well when frozen, which brings us to the global warming issue.

When Europeans brought the disease to the Americas, native populations were devastated—smallpox killed them by the millions. Smallpox’s effect on Arctic groups was similar, and burying the bodies of victims in permafrost may have allowed for extremely long-term survival of the variola viruses.

This wouldn’t be a concern, except recently permafrost has shown itself to be a little less permanent than we’re used to. Global warming—which seems to be occurring more rapidly in the arctic—is thawing the permafrost, and exposing bodies that have been buried and preserved for hundreds of years. That some of these bodies very likely contain the smallpox virus has some people worried. A single encounter with the wrong corpse as it emerges from the permafrost could potentially result in an outbreak, and, having had no previous exposure to the virus, most of us would fare no better than the Native Americans did 400 years ago.

Not all knickers are twisted here, however. Some believe that the gradual thawing caused by global warming will actually reduce the chances of smallpox infection. The virus usually can’t survive being in a thawed body for more than a few days, so most infected bodies will lose their virulence before anyone is likely to encounter them. This depends on the type of permafrost, though—dry permafrost (as opposed to ice-rich permafrost) preserves bodies better, and would increase the chance of viral transmission, so never say never. And I never do.

Oh, wait.

Mar
26
2008

In Alamosa, Colorado the water is not safe to drink. It's contaminated with Salmonella bacteria. Although Salmonella outbreaks are pretty common, it is pretty rare to find it in a municipal water source. As of 11 a.m. Monday the 24th, 217 cases of Salmonella were reported, with 68 confirmed cases. For more information about this outbreak see the following links:
Colorado Department of Health
National Public Radio
CBS

I drink tap water and will continue to do so, it's safe and better for the environment. Where do you get your drinking water from and why?