STD Awareness: Is Chlamydia Bad?

chlamydiaPerhaps your sexual partner has informed you that they have been diagnosed with chlamydia, and you need to get tested, too. Maybe you’ve been notified by the health department that you might have been exposed to chlamydia. And it’s possible that you barely know what chlamydia even is, let alone how much you should be worried about it.

Chlamydia is one of the most common sexually transmitted diseases (STDs) out there, especially among young people. It can be spread by oral, vaginal, and anal sex, particularly when condoms or dental dams were not used correctly or at all. It is often a “silent” infection, meaning that most people with chlamydia don’t experience symptoms — you can’t assume you don’t have it because you feel fine, and you can’t assume your partner doesn’t have it because they look fine. If you’re sexually active, the best way to protect yourself is to know your partner’s STD status and to practice safer sex.


Chlamydia increases risk for HIV, leads to fertility and pregnancy problems, and might increase cancer risk.


The good news about chlamydia is that it’s easy to cure — but first, you need to know you have it! And that’s why it’s important for sexually active people to receive regular STD screening. Left untreated, chlamydia can increase risk of acquiring HIV, can hurt fertility in both males and females, can be harmful during pregnancy, and might even increase risk for a certain type of cancer. So why let it wreak havoc on your body when you could just get tested and take a quick round of antibiotics?

To find out just how seriously you should take chlamydia, let’s answer a few common questions about it.

Can Chlamydia Increase HIV Risk?

Chlamydia does not cause HIV. Chlamydia is caused by a type of bacteria, while HIV is a virus that causes a fatal disease called AIDS. However, many STDs, including chlamydia, can increase risk for an HIV infection, meaning that someone with an untreated chlamydia infection is more likely to be infected with HIV if exposed to the virus. Continue reading

STD Awareness: Sexual Transmission of Zika Virus

Zika

Zika virus. Image: Cynthia Goldsmith, CDC

I first heard of Zika virus in an epidemiology class, when another student made on offhand remark: “Did you know Zika virus can be transmitted sexually?” Ever vigilant for material for the STD Awareness column, I excitedly scribbled the name of the virus in my notes. But upon further investigation, I found that there were only a couple of documented cases of the sexual transmission of this virus that no one had heard of, and decided there was no reason to freak people out about yet another potential STD when rates of more common STDs, like chlamydia and gonorrhea, were on the upswing.

A year later, Zika virus was splashed across headlines on a daily basis, mostly for its newfound association with birth defects, but also in light of revelations that it could be transmitted by sex.


Access to condoms and reliable contraception is more vital than ever.


While Zika virus is usually transmitted by mosquito bites, the discovery that it can be sexually transmitted made it the only known virus that could be spread both sexually and by mosquitoes. It’s also the only known mosquito-borne virus that can cross the placenta to harm a fetus. Like several other viruses, including CMV and rubella, Zika is implicated in serious birth defects. But many health authorities worry that its potential as a sexually transmitted pathogen is dangerously underestimated. As of August 31, there have been 23 confirmed sexually transmitted cases of Zika virus in the United States — but sexual transmission will rise as the virus jumps into local mosquitoes, which will also make it difficult or impossible to tell if a sexually active Zika patient got the virus from sex or directly from a mosquito.

Earlier this year, sexually transmitted Zika virus in Texas made headlines, with many journalists incorrectly proclaiming it the first known case of sexual transmission. In fact, Zika’s sexual transmission was first documented in 2008, before “Zika” was a household name and the married couple who published their experience in a scientific paper thought they could share their STD status in relative obscurity. Despite referring to themselves as “Patient 1” and “Patient 3,” a science reporter quickly figured it out and (with their permission) revealed their identities in a 2011 article — still years before Zika-bearing mosquitoes would hit the Americas and trigger a microcephaly epidemic that propelled the virus to infamy. Continue reading

STD Awareness: Gonorrhea’s Ever-Growing Resistance to Antibiotics

gonococci

Gonococci, the bacteria that cause gonorrhea.

Ever since the advent of effective antibacterial therapies less than a century ago, humans with access to these drugs can easily cure gonorrhea. Most of us in the developed world have forgotten that this disease was once a leading cause of infertility in women and blindness in babies — sulfa drugs and antibiotics not only erased these infections from our bodies, they also erased memories of gonorrhea’s dangers from our collective consciousness.


There are two drugs remaining to treat gonorrhea, and resistance to them is climbing higher as the years march on.


Unfortunately, thanks to their talent for genetic gymnastics, gonococci, the bacteria that cause gonorrhea, have been evolving resistance to every drug we’ve thrown at them — to tetracycline, to penicillin, and more recently to fluoroquinolones. One class of antibiotics remains to treat gonorrhea: cephalosporins. In 2013, Centers for Disease Control and Prevention (CDC) Director Tom Frieden warned that we could find ourselves in a “post-antibiotic era” – unless we take precautions. And, just two weeks ago, the latest study from the CDC’s Gonococcal Isolate Surveillance Project sounded the alarm that the post-antibiotic era is drawing ever closer, especially when it comes to gonorrhea.

Azithromycin and ceftriaxone, the two drugs that are used in combination to deliver a one-two punch to invading gonococci, are the best antibiotics remaining in our arsenal. Azithromycin is taken by mouth, while ceftriaxone is administered by a shot, and when taken together they team up to target different weak points in gonococci’s armor. Azithromycin interferes with the bacteria’s ability to make proteins, shutting the cells down, while ceftriaxone causes the cell wall to fall apart. However, the gonococci can acquire resistance. For example, in the case of azithromycin, a resistant bacterium can spit out the drug before it has a chance to kill it, or it can change the shape of its protein-making apparatus such that the drug can’t attach to it.  Continue reading

STD Awareness: What Does “Congenital Syphilis” Mean?

Treponema pallidum, the bacteria that causes syphilis

Treponema pallidum, the bacteria that causes syphilis

Congenital syphilis, for centuries a leading cause of infant mortality, is often thought of as an antique affliction, relegated to history books — but it is on the rise again. Between 2012 and 2014, there was a spike in congenital syphilis rates, which increased by 38 percent and are now the highest they’ve been in the United States since 2001. As of 2014, the last year for which we have data, more babies were born with syphilis than with HIV.

The word “congenital” simply means that the baby was born with syphilis after being infected in the womb. When an expecting mother has syphilis, the bacteria that cause the disease can cross the placenta to infect the fetus — and will do so 70 percent of the time. As many as 40 percent of babies infected with syphilis during pregnancy will be stillborn or will die soon after birth. It can also cause rashes, bone deformities, severe anemia, jaundice, blindness, and deafness. Congenital syphilis is especially tragic because it’s almost completely preventable, especially when expecting mothers have access to adequate prenatal care and antibiotics. Penicillin is 98 percent effective in preventing congenital syphilis when it is administered at the appropriate time and at the correct dosage.


More babies are being born with syphilis — but this trend can be reversed with wider access to prenatal care.


Incidence of congenital syphilis is growing across all regions of the country, but rates are highest in the South, followed by the West. Rates have also been increasing across ethnic groups, but, compared to white mothers, congenital syphilis rates are more than 10 times higher among African-American mothers and more than 3 times higher among Latina mothers, illustrating the need to increase access to prenatal care for all expecting mothers — and to ensure that this prenatal care is adequate.

Anyone receiving prenatal care should be screened for syphilis at their first visit, and some pregnant people — including those at increased risk or in areas where congenital syphilis rates are high — should be screened a second time at the beginning of the third trimester and again at delivery. Continue reading

STD Awareness: June Is National Congenital Cytomegalovirus Awareness Month

CMVPop quiz: Can you name the virus that most commonly infects developing fetuses when they are still in the womb?

Here’s a hint: June is National Congenital Cytomegalovirus Awareness Month.

In case that clue didn’t make it obvious enough, I’ll tell you the answer. The most common infection among developing fetuses is caused by a virus you might not have heard of: cytomegalovirus, or CMV. Around 30,000 children are born with this infection every year, and some of these babies will go on to develop serious problems because of it. National Congenital Cytomegalovirus Awareness Month is a time to learn about how CMV can affect pregnancy.


Cytomegalovirus can damage developing brain cells early in an embryo’s gestation.


This year, it might be of even greater interest, given the parallels that can be drawn between CMV and Zika virus, the emerging pathogen that has been dominating headlines lately. First of all, both CMV and Zika virus can be transmitted sexually, though they are not the first things you think of when the topic of STDs comes up, as they are overshadowed by more famous sexually transmitted viruses like herpes and human papillomavirus. While many of us are infected with CMV as children, we can also be infected as adults, often through sexual transmission — the virus can be found in cervical and vaginal secretions, saliva, and semen. The sexual transmission of Zika virus is not as well understood, but we know it can be found in semen, and there are documented cases of men passing the virus to sex partners through vaginal and anal intercourse. It might even be transmitted from a male to a partner by oral sex.

Second of all, both CMV and Zika virus are associated with birth defects. However, while the connection between CMV and birth defects has been known to us for decades, it was only in April that the Centers for Disease Control and Prevention concluded that Zika virus can cause fetal brain defects (though we’re still waiting for conclusive proof). Microcephaly is probably the most infamous of the birth defects associated with Zika virus, as well as CMV, but it’s not well defined. When you get down to it, though, microcephaly just refers to an abnormally small head, which itself might be indicative of a brain that has failed to develop fully. Continue reading

STD Awareness: Which STDs Are Resistant to Antibiotics?

pillsYou’ve probably heard of MRSA, which is pronounced “mersa” and stands for methicillin-resistant Staphylococcus aureus — a strain of bacteria that is resistant to methicillin, as well as pretty much every other antibiotic out there. MRSA is an example of evolution by natural selection — what didn’t kill its ancestors made them stronger, spawning a drug-resistant strain.


There are drug-resistant strains of gonorrhea, trichomoniasis, and syphilis.


Evolution is the force behind life’s diversity. Normally, diversity is a good thing — but when it comes to microbes that cause diseases like gonorrhea, trichomoniasis, and syphilis, these organisms’ ability to evolve new defenses against our antimicrobial drugs isn’t good for us.

STDs have plagued us for millennia, but it wasn’t until the 20th century that we finally developed antibiotics, which gave us a powerful tool against many of our most formidable sexually transmitted foes. Suddenly, scourges like gonorrhea and syphilis could be quickly and easily treated with a dose of penicillin.

Problem solved, right? Nope. Enter evolution by natural selection. Continue reading

STD Awareness: Will STDs Go Away on Their Own?

teensCan gonorrhea go away without treatment? Does chlamydia eventually clear up? Can trichomoniasis go away on its own? These are the kinds of questions people pose to Google before Google sends them here — at least that’s what I learned by looking at the blog’s stats. They’re tricky questions to tackle, and for so many reasons.

Some viral STDs stay with you for life, such as herpes and HIV. Others, such as hepatitis B and human papillomavirus (HPV), can be prevented with vaccines but cannot be cured. It’s also possible for the immune system to defeat hepatitis B virus and HPV — but in some cases, these viruses are able to settle in for the long haul, causing chronic infections that can endure for life and even lead to cancer.


Left untreated, syphilis can kill, and gonorrhea can cause infertility.


Non-viral STDs, like chlamydia and gonorrhea, can be cured. However, they usually don’t have symptoms, or symptoms can come and go, making it seem like an infection went away when it actually didn’t. You can’t know your STD status without getting tested, and you can’t self-diagnose an STD based on symptoms and then assume the infection went away when symptoms subside. Getting tested can uncover a problem and clear the way for treatment.

Nonetheless, people want to know if an STD can go away by itself — but there aren’t many studies on the “natural history” of curable STDs like gonorrhea, chlamydia, and trichomoniasis. Studying the natural course of a curable infection would require that scientists put their subjects at risk of the dangers of long-term infection, and no ethics board would approve such an experiment. Continue reading