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

STD Awareness: Are Condoms Really Necessary?

condoms in packetsCondoms are one of the best ways for sexually active people to avoid sexually transmitted diseases (STDs), but many worry that people are becoming more lax about protecting themselves. There are all kinds of myths swirling around about condoms — such as that they aren’t effective or that they kill the mood. And, thanks to anti-HIV medications, some people no longer see condom use as a matter of life or death.

The Centers for Disease Control and Prevention (CDC) recently announced that 2014 saw record highs in chlamydia, syphilis, and gonorrhea, which is a stark reminder that condoms protect against more than just HIV. So, even if you’re using medications to protect yourself from HIV, remember that syphilis is making a comeback, and can cause serious damage or even death when untreated, and that gonorrhea is rapidly evolving resistance to the last good drugs we have to treat it. Condoms are just as relevant as ever!

HIV

In 2014, the CDC announced it would start using the term “condomless sex” instead of “unprotected sex” to recognize that people could engage in condom-free sex, but still protect themselves from HIV by using Truvada, or pre-exposure prophylaxis (PrEP). Truvada is the first drug approved by the FDA to prevent HIV, and it can be taken by HIV-negative individuals to help their body ward off the virus before an infection can establish itself. The pill must be taken daily — using it inconsistently reduces its effectiveness. Continue reading

STD Awareness: Mycoplasma genitalium

Image of Mycoplasma genitalium adapted from American Society for Microbiology.

“I’m not small, I’m just streamlined!” Image of Mycoplasma genitalium adapted from American Society for Microbiology.

In November and December of last year, headlines touting a “new” STD made an ever-so-minor flurry across the Internet. CNN referred to it as “mycoplasma genitalium, or MG” — Mycoplasma genitalium is the name of the teardrop-shaped bacteria that can cause several diseases in the urinary or reproductive tracts, such as urethritis and pelvic inflammatory disease.

M. genitalium is the smallest living organism known to science, having “devolved” from more complex organisms — but that doesn’t mean it can’t pack a punch! While these bacteria have surely been around for millennia, we only discovered them in the 1980s. Since then, we’ve known that M. genitalium fits the profile of a sexually transmitted pathogen — the only reason it made the news last year was that a team of British researchers published further evidence that this bug is indeed sexually transmitted and capable of causing disease.


Genital mycoplasmas can be cured — but a doctor needs to know what she’s looking for in order to prescribe the correct antibiotic!


An infection with M. genitalium could more generally be called a “genital mycoplasma.” The term “genital mycoplasmas” refers to a category of several different species of sexually transmitted bacteria, most notably Mycoplasma genitalium, but also less common species, such as Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum. M. genitalium is considered an “emerging pathogen,” because it is only over the past couple of decades that technology has allowed us to study these bacteria, along with other genital mycoplasmas.

Risk factors for infection include multiple sexual partners and not using condoms during sex. It is thought that most people with an M. genitalium infection don’t have immediate symptoms — 94 percent of infected men and 56 percent of infected women won’t notice anything amiss. That doesn’t mean it can’t do damage. Continue reading