STD Awareness: The Curious Case of Chancroid

Haemophilus ducreyi arrange themselves in parallel rows, which researchers have called “railroad tracks,” “schools of fish,” and “fingerprints.” Image: Mike Miller, CDC

Earlier this year, I asked a room full of scientists and medical professionals to raise their hands if they’d ever heard of chancroid. Everyone sat there, motionless, confused by the odd syllables I had uttered — shan kroyd. If you’ve never heard of chancroid, you’re not alone.

Chancroid is a sexually transmitted disease (STD) brought to you by Haemophilus ducreyi, a type of bacteria that can pass through microscopic tears in the skin during sexual contact. When one partner is infected, there is a 1 in 3 chance the other will become infected. An infection can cause painful sores and swollen lymph nodes, most often in the genital region. About half of people with chancroid infections will experience “buboes,” or swollen lymph glands that might rupture. Before it could be cured with antibiotics, a persistent infection could cause permanent skin damage.


Humanity can make chancroid the first STD to go extinct.


One reason you probably haven’t heard of chancroid is that, in the developed world at least, it has mostly disappeared. In fact, researchers believe chancroid can be completely wiped off the planet — which would make it the first STD ever to be forced into extinction. How amazing would that be?

Chancroid has been hopping from loin to loin since at least the days of the ancient Greeks, and was common until the 20th century, when rates began to decline. Thanks to antibiotics, U.S. chancroid rates decreased 80-fold between 1947 and 1997, all but vanishing by the late 1950s. It was virtually unheard of until there was another spike in the 1980s, correlating with the crack epidemic. But, since 1987, cases have been steadily declining. Continue reading

STD Awareness: Antibiotic-Resistant Syphilis

Treponema pallidum under a microscope. Image: Dr. Edwin P. Ewing, Jr., CDC

The image to your right, with lively yellow splotches against a pale green background, is not a long-lost Jackson Pollack piece, and the dark squiggly lines aren’t strands of paint haphazardly splattered onto a canvas. In fact, those squiggly lines are magnified images of the spiral-shaped bacteria species Treponema pallidum. You might not have heard of T. pallidum, but you’ve probably heard of syphilis, the sexually transmitted disease (STD) that these bacteria cause. While syphilis isn’t as common as other STDs, like chlamydia and HPV, it’s still out there, and occasionally communities experience outbreaks. It’s always best for sexually active people to be screened for STDs and practice safer sex.


The evolution of syphilis strains that are resistant to certain antibiotics underscores the need to use antibiotics properly.


Syphilis can inflict serious long-term damage — in fact, before the introduction of antibiotics, syphilis was the worst STD out there! Known as the Great Pox when it descended upon Europe 500 years ago, it could cause large and painful boils. Eventually, natural selection led to T. pallidum’s evolution into a form with milder symptoms, which benefited the bacteria by enabling its less boil-ridden (and presumably more attractive) human hosts to spread it farther and wider. Nevertheless, the symptoms of syphilis, if present, still include infectious sores, and when the disease goes untreated, it can cause severe, possibly fatal, damage to the nervous system.

Back in the day, there were myriad inadequate “treatments” for syphilis, ranging from straight-up quackery to the use of partially effective but toxic chemicals such as mercury. But a century ago, in 1912, a new arsenic-based chemical called Neosalvarsan was hailed as a “magic bullet.” Unfortunately, this treatment took weeks or even more than a year to administer — and had dangerous side effects. Quack treatments continued to flourish, and it wasn’t until the widespread adoption of penicillin in the 1940s that an effective cure with few side effects was available.

But natural selection endures; in fact, by flooding T. pallidum’s habitat with certain antibiotics, we’ve created an environment that favors the organism’s evolution against us. While not as immediately threatening as antibiotic-resistant gonorrhea, syphilis has been quietly evolving resistance to some of the antibiotics we use to treat it. This underscores the importance of using antibiotics correctly and emphasizing safer-sex practices, such as using latex condoms during vaginal or anal intercourse and during oral contact with a penis. Continue reading

Over 90 Percent of What Planned Parenthood Does, Part 9: Treating Urinary Tract Infections

Urinary tract infections occur when certain bacteria invade the urethra.

Welcome to the latest installment of “Over 90 Percent of What Planned Parenthood Does,” a series on Planned Parenthood Advocates of Arizona’s blog that highlights Planned Parenthood’s diverse array of services — the ones Jon Kyl doesn’t know about.

A urinary tract infection (UTI) affects the urinary system, most notably the urethra. Symptoms might include an increased urge to urinate, accompanied by a burning sensation; urine might be cloudy or bloody. Among adults, UTIs are 50 times more common in people with vaginas than in people with penises, probably due to the shorter distance bacteria travel from the bowel. If you have a vagina, there is more than a 50 percent chance that you’ll have at least one UTI in your lifetime. And, if you’re unlucky enough to be in this group, there’s a 20 percent chance that you’ll develop recurrent UTIs (three or more infections yearly). Annually, UTIs prompt an estimated 8 million visits to health-care providers, costing at least $1 billion.


How can urinary tract infections be prevented?


Although symptoms often recede without medical intervention, it’s important to seek treatment for persistent UTIs because the infection could spread. If you are or have been sexually active, it is also important to ensure you don’t actually have a sexually transmitted disease.

Causes of UTIs

When certain species of fecal bacteria wend their way from the bowel into your urethra, they might initiate an infection. Up to 90 percent of UTIs are caused by certain strains of Escherichia coli; the rest are caused by Staphylococcus saprophyticus, Proteus mirabilis, Klebsiella pneumoniae, and a few other species. Continue reading

STD Awareness: Syphilis

Treponema pallidum, the causative agent of syphilis, is seen in this electron micrograph adhering to a surface with the tapered end of its structure. Image obtained from the CDC’s Public Health Image Library.

Treponema pallidum, the causative agent of syphilis, is seen in this electron micrograph adhering to a surface with the tapered end of its structure. Image: Public Health Image Library, CDC

When syphilis first descended upon Europe, it was seen as a new plague, and anxiety and blame coalesced around this mysterious scourge. Was it a punishment from God? Was it introduced by a hated Other? Was it caused by the stars’ alignment or the presence of “bad air”? The panic it provoked foreshadowed the hysteria that surrounded the emergence of HIV in the 1980s, as syphilitics were discriminated against, feared, or thought to have received punishment for their “unbridled lust.”

We now know that syphilis is not caused by supernatural forces, foreigners, or “bad air,” but rather by a species of spiral-shaped bacteria called Treponema pallidum, which can cause infections in the vagina, anus, urethra, or penis, as well as the lips and mouth. It is mostly spread by sexual contact — vaginal or anal intercourse, as well as oral sex — in which one person comes into contact with a syphilis sore. These sores can be hidden on the cervix or in the vagina, urethra, rectum, or mouth, making it not immediately apparent that one is infected with syphilis. Syphilis can also spread to a fetus during pregnancy. Sexually active people can reduce their risk of contracting syphilis by using latex barrier methods such as condoms or dental dams. Continue reading

STD Awareness: Bacterial Vaginosis and Chancroid

Editor’s Note: Please see our post of November 2, 2015 to learn if bacterial vaginosis (BV) can cause sores, and to get the scoop on whether or not it’s actually an STD.

Sexually transmitted diseases can be caused by viruses, bacteria, protozoans, and even animals. Bacterial vaginosis and chancroid are both infections caused by bacteria, which means that they can be treated with antibiotics. While bacterial vaginosis only affects people with vaginas, chancroid disproportionately affects people with penises. You can seek diagnosis and treatment for bacterial vaginosis and chancroid at a Planned Parenthood health center, as well as health clinics, private health-care providers, and health departments.

Bacterial vaginosis is caused by an imbalance of bacteria species in the vagina. Image: renjith krishnan / FreeDigitalPhotos.net

Bacterial vaginosis is caused by an imbalance of bacteria species in the vagina. Image: renjith krishnan / FreeDigitalPhotos.net

Bacterial Vaginosis
Bacterial vaginosis seems to be most commonly caused by the bacteria species Gardnerella vaginalis. Scientists aren’t quite sure how this infection is caused, but risk seems to correlate with a change in sexual partners, having multiple sexual partners, douching, or using an intrauterine device; it can also occur in females who have never been sexually active. It is more common in pregnant women. There is no counterpart to this infection in males, although G. vaginalis can be found in their urethras; this raises the possibility that bacterial vaginosis can be sexually transmitted, in which case it could be directly transmitted between two females or indirectly transmitted from one female to another via a male.

Bacterial vaginosis seems to result from an imbalance in the vaginal flora (“flora” is a somewhat fanciful term for the bacteria that live in your body; under normal circumstances they are harmless and even beneficial). Vaginas usually are habitat to a population of bacteria called Lactobacillus, which produce hydrogen peroxide as a byproduct. When the number of Lactobacillus declines, G. vaginalis is able to move in on Lactobacillus’ old territory. The decrease in Lactobacillus and increase in G. vaginalis leads to a rise in the vagina’s pH. The new vaginal environment is less acidic and more alkaline; a vaginal pH of more than 4.5 is one criterion for the diagnosis of bacterial vaginosis. Another symptom includes a vaginal discharge that may smell somewhat fishy. There might also be genital itching or pain during urination. It is also possible not to have symptoms. Continue reading

Can Cranberry Juice Cure Urinary Tract Infections?

Cranberry products have a reputation for fighting urinary tract infections. But is this reputation deserved? Image: FreeDigitalPhotos

An increased urge to urinate. A burning sensation when you do. These are two of the signs of a urinary tract infection (UTI), an incredibly unpleasant condition that can seem to come out of nowhere. Anyone can get a UTI, but among adults they are about 50 times more common in females than in males. Certain microorganisms cause these infections, often when bacteria from feces are introduced into the urinary tract. Although symptoms often clear up without medical intervention, it is very important to seek treatment for a persistent UTI because the infection could spread and become much more serious. (If you are or have been sexually active, it is also important to make sure you don’t actually have a sexually transmitted infection.)

Cranberry products — either as juice (sweetened, unsweetened, or blended with other fruit juices) or capsules — are considered by many to be an effective home remedy for UTIs. While cranberries are a well-known and accessible treatment, the evidence for their efficacy is not very strong. Why, then, are they such a popular treatment? It could be due simply to the placebo effect, an amazing phenomenon in which our expectations help shape our experiences. It could be that symptoms often clear up on their own, but we attribute our improvement to whatever remedies we happened to be trying at the time. It could be that drinking extra fluids (e.g., cranberry juice) helps flush the bacteria from our bodies as we urinate more. Or, it’s possible that cranberries do help clear up UTIs, but we just don’t have solid evidence yet. Continue reading