STD Awareness: The Curious Case of Chancroid

Posted on September 11, 2017 by Anna C.

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 →

Why Do Newborns Need the Hepatitis B Vaccine?

Posted on May 1, 2017 by Anna C.

The first vaccine a baby receives — within hours or days of birth — protects them from hepatitis B virus (HBV). In a lot of people’s minds, HBV is associated with drug use and sexual activity — which stigmatizes people who have been infected with HBV or are carriers of the virus. Unfortunately, this stigma causes a lot of people to question why babies even need to be vaccinated against it, often pointing to “Big Pharma” conspiracy theories. A lot of other people are put off by the misconception that the HBV vaccine is made with human blood (it’s not).

May is Hepatitis Awareness Month, a time to learn about a childhood vaccine that’s saved millions of lives.

There are perfectly good reasons to vaccinate babies against HBV, mainly that HBV is the leading cause of liver cancer, itself one of the Top 10 types of cancer worldwide. Nine out of 10 infants born to a mother who is an HBV carrier will develop chronic infections and become carriers themselves — and a quarter of them will die prematurely of liver disease. Babies who develop chronic HBV infections are 63 times more likely to develop liver cancer than non-carriers, a connection that is 2 to 3 times stronger than the link between smoking and lung cancer.

When it comes to HBV, age at infection matters. Most people with chronic HBV infections are exposed at birth or in early childhood, when they are most likely to develop chronic, lifelong infections — whereas only 2 to 6 percent of infected adults will develop chronic infections, with only 15 percent of them eventually dying from liver disease. The fact that chronic infection risk is inversely correlated with age at infection means that birth is the time when a child is the most vulnerable to this virus — hence the importance of vaccinating as early as possible. Continue reading →

Hepatitis B Vaccine: The Importance of the Birth Dose

Posted on April 20, 2016 by Anna C.

Did you know that Saturday kicked off National Infant Immunization Week, which is part of a worldwide observance that shines the spotlight on the importance of vaccination? Most of us think of infant immunization as a tool to protect babies from childhood illnesses like chickenpox and whooping cough. But did you know that one infant immunization protects them from cancer later in life?

Globally, hepatitis B virus (HBV) is one of the top causes of cancer. Every year, it kills more than three-quarters of a million people worldwide. An HBV infection might be defeated by the immune system, but when it’s not, it can become a chronic infection. And chronic infections can lead to serious health outcomes, including cirrhosis and liver cancer. The younger you are, the less likely you’ll be able to fight off an HBV infection — 90 percent of infants infected with HBV will develop chronic infections, and 25 percent of them will go on to die prematurely after developing liver disease. Compare that to 2 to 6 percent of infected adults who will develop chronic infections.

Because infants are so vulnerable to developing chronic infections, vaccinating them against hepatitis B at birth makes sense.

Most people think of hepatitis as a bloodborne disease, and it is spread very efficiently when IV drug users share needles, during needle-stick accidents and other occupational injuries, or by using contaminated piercing needles, tattoo equipment, or acupuncture needles. Even sharing items like razors, toothbrushes, and nail clippers can do it, as the virus can survive outside of the human body for a week. HBV can also be spread by sexual contact, including vaginal and anal sex.

Lastly, babies and children can be at risk as the virus can be transmitted from mother to infant during birth, and during early childhood when risk of chronic infection is high. A significant number of people with chronic infections acquired them during early childhood, but we don’t know exactly how they got them, as their parents and other household contacts were negative for the virus or its antibodies. Since infants and children are at the highest risk for developing chronic infections, focusing on that population for prevention is very important.

Luckily, there’s a vaccine. Continue reading →

Teen Talk: What Is Kissing Disease?

Posted on February 8, 2016 by Anna C.

If you’re a total dork like me, you might have some plush microbes hanging out on your desk or in your bedroom. The one that represents Epstein-Barr virus is especially adorable (look to your right and try not to coo in delight!). I just want to grab it, cuddle up to it, and fall asleep in its pillowy purple-pink embrace.

In reality, Epstein-Barr virus, or EBV for short, is not the most warm-and-fuzzy microbe of the bunch. I’d way rather have a cold. Why? Because EBV causes mono, which is more whimsically known as the kissing disease. And, despite that cute moniker, kissing disease can be most unpleasant.

Take it from one mono survivor: “Mono stinks!”

First, an explanation of why mono is also called the kissing disease. Merely being in the presence of someone with mono won’t put you at risk, even if you’re both in the same room — you need to be actively swapping spit with them to be exposed to the virus. Kissing is probably the most famous way for two people to exchange saliva, but sharing cups, eating utensils, or toothbrushes can do it, too. After exposure to the virus, symptoms could show up in 4 to 6 weeks.

Second, an explanation of why mono can be so terrible. While not all teenagers and young adults who are infected with EBV will develop symptoms, those who do probably won’t enjoy the experience. Symptoms include extreme fatigue, head and body aches, sore throat, and fever. It’s bad enough to have those symptoms for a few days, but mono might seem to go on and on with no end in sight. Most people are better in 2 to 4 weeks, but even then it could take another few weeks to get back to 100 percent. And some unlucky people can experience these symptoms for six months or even longer! In addition to these nasty symptoms, serious complications are possible. Continue reading →

STD Awareness: Is Bacterial Vaginosis a Sexually Transmitted Disease?

Posted on November 2, 2015 by Anna C.

Gardnerella vaginalis under a microscope. Image: K.K. Jefferson/Virginia Commonwealth University

Bacterial vaginosis, or BV, is the most common vaginal infection among people 15 to 44 years of age. It’s caused by an overgrowth of harmful bacteria, such as Gardnerella vaginalis. A healthy vagina hosts thriving populations of Lactobacillus bacteria species, but when these “good” bacteria are crowded out by certain types of “bad” bacteria, the vaginal ecosystem can be shifted, causing BV.

There is a lot of confusion about BV. Is it a sexually transmitted disease (STD)? What are the symptoms? How can you avoid it?

All good questions. Let’s examine them one by one.

Is BV an STD?

The consensus seems to be that BV isn’t officially an STD, but even reliable sources have somewhat contradictory information. Planned Parenthood doesn’t list BV as an STD on their informational webpages. The Centers for Disease Control and Prevention (CDC) does include BV on their STD website, but also says that “BV is not considered an STD.”

On the other hand, the Office on Women’s Health says that “BV can … be caused by vaginal, oral, or anal sex” and that “you can get BV from male or female partners.” And there’s an entire chapter devoted to BV in the premier medical textbook on STDs, and its authors say that, while sexually inexperienced females can get BV, “the weight of evidence supports sexual transmission” of G. vaginalis, the bacteria species most famously implicated in BV infections.

The same webpage on which the CDC declared BV not to be an STD also says that it can be transferred between female sexual partners. Indeed, women who have sex with women have higher rates of BV. Since vaginal fluid could spread BV, partners can change condoms when a sex toy is passed from one to another, and use barriers like dental dams when engaging in cunnilingus (oral contact with the female genitalia) or rimming (oral contact with the anus).

What about heterosexual transmission? Continue reading →

STD Awareness: Do Sexually Transmitted Diseases Increase HIV Risk?

Posted on August 18, 2014 by Anna C.

You might have heard that having an STD like syphilis, herpes, or gonorrhea can make it easier to catch HIV, the virus that causes AIDS. But have you ever wondered if this was true? Maybe it’s just a simple correlation — for example, someone who doesn’t practice safer sex would be more likely to catch HIV along with any other STD. That doesn’t mean that one causes the other, does it?

Common STDs like herpes and trichomoniasis can increase HIV risk.

But it’s not a mere correlation. If you take one person with an STD and one person without an STD and expose them both to HIV through sexual contact, the person with the STD will be at least two to five times more likely to become infected with HIV. Why is that? First, many STDs can make you more susceptible to an HIV infection. Second, the immune response triggered by many sexually transmitted infections can summon the types of immune cells that HIV targets.

Furthermore, if a person with HIV is co-infected with another STD, he or she is more likely to transmit HIV to a partner. In other words, STDs can make a person with HIV more infectious. HIV is more likely to appear in their genital secretions, making it easier to transmit HIV through sexual activity. Continue reading →

My Partner Just Told Me They Have Herpes. I Don’t. Now What?

Posted on June 30, 2014 by Anna C.

Has your new partner just informed you that he or she has herpes? People have many reactions when hearing this kind of news — and, depending on how informed you are about herpes, your reaction might be tinged with panic or fear. If that’s your instinct, try to keep those feelings in check: Your partner might be feeling very vulnerable, so it’s best not to react with shunning or shaming.

More than 80 percent of people with genital herpes are unaware of their infections.

By being open about his or her STD status, your partner has demonstrated a sense of responsibility toward your sexual health and a respect for your ability to make informed decisions. It’s possible that your partner was not given this same consideration by the person from whom he or she contracted herpes — some people with genital herpes choose not to disclose their status, while most don’t even know they carry the virus in the first place.

Herpes is more widespread than most of us realize. It can be caused by one of two strains of the herpes simplex virus: HSV-1 or HSV-2. While HSV-1 is more commonly associated with cold sores and HSV-2 is more commonly associated with genital herpes, either virus can infect the genital area. One estimate states that 1 out of 5 American females and 1 out of 9 American males between 14 to 49 years of age have a genital HSV-2 infection.

Now that you know your partner has herpes, you might have some questions. How easy is it to transmit genital herpes from one partner to another? What can you do to minimize your chances of catching the virus? And, while it is certainly stigmatized in our culture, is herpes something to fear? Continue reading →