Why are syphilis cases increasing?

[00:00:00] Host Amber Smith: Upstate Medical University in Syracuse, New York invites you to be "The Informed Patient" with the podcast that features experts from Central New York's only academic medical center. I'm your host, Amber Smith. The rate of syphilis infections in the United States continues to rise, by 80% since 2018, and news reports say we're recording the highest rate of new infections since 1950. Here to explain what's going on is Dr. Elizabeth Asiago Reddy. She's the chief of infectious disease at Upstate Medical University. Welcome back to "The Informed Patient," Dr. Asiago Reddy.

[00:00:37] Elizabeth Asiago Reddy, MD: Thank you so much for having me, Amber.

[00:00:40] Host Amber Smith: So why are national rates of syphilis rising?

[00:00:44] Elizabeth Asiago Reddy, MD: There are a couple different factors at play here. One of them is reduced condom use, which we've been seeing a trend ever since approximately 2010. And we believe a lot of that has to do with the reduction in severity of illness associated with HIV, once we had really good medications to treat HIV. So we saw a peak in condom use in the early 2000s associated with the HIV epidemic, and we're obviously very happy to see the improved treatments and accessibility for HIV care, but that does seem to have been associated with a reduction in condom use that has continued over time. So we're seeing this year over year that people are using condoms less frequently than they used to.

Another factor is dating apps. A lot of people are attributing dating apps to a general rise in sexually transmitted infections. It's a lot easier to find partners and potentially easier to find anonymous partners, and it can be more difficult to track down partners and treat people who might have been exposed to a sexually transmitted infection. In a situation where people are traveling outside of their hometown, potentially, for sexual encounters, or having sexual encounters with people that they don't know as well. So that's another feature.

And I think as it relates to syphilis in particular, one of the things that seems to have contributed in the last couple of years is that there's a possibility that people are having more open relationships, be that by choice, so with or without their knowledge that their partner might be having other partners. And as a result, there is more of a rise in syphilis now among women, which was not the case for the previous years before these last couple of years.

[00:02:44] Host Amber Smith: So, by comparison, what's happening with the rates of gonorrhea, because that's another sexually transmitted disease. Is that going up as well?

[00:02:55] Elizabeth Asiago Reddy, MD: Our data for the last year indicated a drop in gonorrhea nationally, um, and a kind of a stabilization in gonorrhea locally. It's a little bit hard to say because the timeframe is shorter. So with syphilis, unfortunately, we've seen a pretty steady increase over the last five to six years, actually even over the last 10 years. Whereas the numbers for stabilization or drop in gonorrhea are, it's a much smaller timeframe, so it's a little bit hard say whether or not that trend will hold.

For syphilis one of the things that concerns me and that's unique to gonorrhea is that the testing is different. So syphilis is done through a blood test, and it is not always routinely done as part of a package of tests that might be done when somebody presents for either gynecologic care or with concern that they might have a sexually transmitted infection. So it's important that that be looked for, and it's not always done.

[00:03:57] Host Amber Smith: So we've been talking about nationally. Does the national picture look the same in Central New York? Are we seeing a rise, as well, with syphilis?

[00:04:06] Elizabeth Asiago Reddy, MD: We have seen, as I mentioned, a general rise over the last 10 years. There have been some cases where, some years where it's ebbed and flowed a little bit in terms of the numbers. But unfortunately we've seen a couple of years where the numbers have risen quite a bit. They might be a little bit down the next year, and then they're back up the following year. So the trend is, unfortunately, one that matches the national trend, which is one of general increase.

[00:04:34] Host Amber Smith: I read that the state with the highest rate of infectious syphilis, 84 cases per 100,000 people, was South Dakota, and that state has a lot of wide open spaces. What's going on with South Dakota?

[00:04:46] Elizabeth Asiago Reddy, MD: So part of that seems to be related to an excess risk among Native Americans. And there's a large population of Native Americans in South Dakota. So I believe that that's a big part of what's happening in that state. And that's reflective of, we know that sexually transmitted infections, obviously, are going to concentrate in groups of people who are seeking the same partners. So. despite the fact that I mentioned that people are seeking partners online, we still overall tend to have partners that match us as it relates to race and ethnicity.

And so there are certain ethnic groups and racial groups that have higher prevalence of certain sexually transmitted infections, and that concentration of syphilis among Native Americans, I suspect, that's exactly what's going on.

[00:05:40] Host Amber Smith: I know syphilis is caused by a bacteria. Where does that bacteria come from, and how does it infect humans to begin with?

[00:05:49] Elizabeth Asiago Reddy, MD: So syphilis is actually, this form of treponema, which is the type of bacteria that this is, Treponema pallidum, it really only causes infections in humans. So it's endemic in humans. There are other types of Treponems that infect other species, but Treponema pallidum is unique to our species, in terms of the diversity of diseases that it causes or illness that it causes. And it is spread by close contact. And that's another unique feature of syphilis that is a little bit different from some of the other sexually transmitted infections, in that it is very efficiently spread by all forms of sexual contact, including oral sex.

And so that is something that some people practice when they are trying to reduce their risk of HIV infections. HIV is not well transmitted through oral sex at all. It's extremely rarely transmitted through oral sex. But that is not the case for syphilis.

So what syphilis does at the early stages is that it causes what's called a painless chancre. So that is a wound or ulceration at the site where the infection first occurred. So that's usually going to be on one of our mucus membranes, whether oral or genital, and it has a very unique property of being able to shut down the nervous response, the nervous system response in that area. And that causes that sore to be painless. So if you actually see one of these, you could be very surprised that it's not really painful. Occasionally it is painful, but most of the time it's not painful. And so that allows these source to go unrecognized in the majority of people who are suffering from them. So that is the way that this continues to spread to other people, because they don't realize that they have anything going on.

They have a sexual encounter. There's close contact with that chancre that has the syphilis bacteria in it, and that spreads to their partner at that time without them potentially even realizing that they have a problem.

[00:07:51] Host Amber Smith: This is Upstate's "The Informed Patient" podcast. I'm your host, Amber Smith. I'm talking with Upstate infectious disease chief, Dr. Elizabeth Asiago Reddy about syphilis.

So beyond this canker, did you call it?

[00:08:07] Elizabeth Asiago Reddy, MD: Chancre.

[00:08:08] Host Amber Smith: What are the symptoms beyond that? Or are there any? How would a person begin to learn that they're infected?

[00:08:15] Elizabeth Asiago Reddy, MD: One of the reasons that we worry a lot about syphilis is that it is a systemic infection, and that is different from some of our other common sexually transmitted infections.

So gonorrhea, chlamydia, even HPV, they almost exclusively live at the site of infection. They very rarely, with the exception of occasional cases of gonorrhea, but they very rarely will spread to other places outside of the site of infection. Syphilis is different. Syphilis is a systemic infection. So once you get stuck with syphilis, unless it's treated in that primary stage where that chancre wound is present. So if it happens to be treated early, you may catch it before it spreads to other parts of the body.

Otherwise, within the first, usually probably about 21 days, but anywhere from 21 to 90 days after the initial infection, it will spread throughout the body. It goes to the lymph nodes at the site of infection, and then from there it goes throughout the bloodstream. It very frequently actually goes into the central nervous system as well. And so we worry about it because it can cause a very large number of symptoms or potentially no symptoms.

We already reviewed that first thing that you might catch or might not catch, which is the chancre. So, certainly any ulceration, genital ulceration that you've not already become familiar with. So, for example, for people who unfortunately have herpes outbreaks, they may be very familiar with that particular pattern in their own body. Aside from that, certainly any new genital ulceration would be something that you would want to have a provider look at.But a lot of times, as I said, people don't even realize that that has happened. So that is your primary stage of syphilis.

The secondary stage of syphilis is extremely diverse in terms of how it could present. Many people don't have any symptoms at all, and they may pass through that stage without even realizing that anything has happened to them. Other individuals can have a whole range of symptoms that include things as vague as just feeling tired, feeling under the weather, potentially some low grade fevers or some lymph nodes that could be swollen either at the site of infection or throughout the body. But others can have very serious signs and symptoms at that stage of infection, which could include things like meningitis, eye infections, changes in their hearing due to central nervous system infections, skin rash. The classic skin rash is present on the palms and soles, but it can be present literally anywhere in the body. It can also impact particular organs within the body. The liver is probably the most common one to be impacted during that relatively early stage that we call secondary syphilis. So those are the manifestations of secondary syphilis

That typically is going to last from about 90 days after initial infection through the approximately... So if people develop symptoms that are severe, most of the time they're going to be seeking medical attention, right? And those symptoms may not go away until they're treated. If their symptoms are mild, then those symptoms may disappear on their own over the course of a couple of months, and the body kind of hides the infection at that point. Once that happens, the person has entered a latent phase.

When somebody is in a latent phase, it may be usually years before this could potentially come back. And in about 20% to 30% of people, if it's totally untreated, it will come back, and it can come back with very devastating, damaging effects in late stages.

[00:12:02] Host Amber Smith: So it can come back years later?

[00:12:04] Elizabeth Asiago Reddy, MD: Correct. Yeah.

[00:12:05] Host Amber Smith: And you wouldn't necessarily even know that you ever had it or were ever infected, but years later you find out you have it.

[00:12:11] Elizabeth Asiago Reddy, MD: Correct. Yeah. So these are reasons why we take this infection very seriously.

[00:12:16] Host Amber Smith: So can it be diagnosed with a blood test?

[00:12:19] Elizabeth Asiago Reddy, MD: Yes. And that is, aside from a very classic looking chancre, the blood test currently is one of the few ways of diagnosing this. So we used to use something called dark-field microscopy, and that is a specific type of microscope setting that can see the Treponem bacterium. But that has fallen out of favor. It's rarely used anymore, and it's largely unavailable.

We're seeking molecular tests, which it would be a PCR (polymerase chain reaction) based test, which obviously we're using to diagnose a lot of other infections. For reasons that we don't understand very well we do not have as much luck diagnosing syphilis with molecular assays as we would like. So right now there are some that are available more for research purposes than for clinical purposes. And essentially what we rely on are blood tests that look at the immune response to syphilis, so an antibody tests.

[00:13:20] Host Amber Smith: But this blood test, you would have to be, as the provider, you would have to be suspecting that it might be this, right?

[00:13:28] Elizabeth Asiago Reddy, MD: This is where some of our challenge is coming with respect to rising rates of syphilis is, we still don't have a perfect idea of who needs to be tested.

There are recommendations by the CDC (Centers for Disease Control and Prevention) and the United States Preventive Services Task Force, so for people who are men who have sex with men, as well as people who have multiple sex partners, or sex workers, and definitely people who are pregnant because of the elevated risk of passing syphilis on during pregnancy. Outside of those particular groups we are likely to miss people, and we just don't always know who are the best people who should be tested.

And the problem that potentially exists with universal testing is, first of all, it's hard to test universally for anything. And second of all, there are some false positives with these tests. So it just becomes more of a challenge of sorting out what's a true positive versus a false positive if you start to test a larger number of people. So that is where I think some of this comes from in terms of the rise in syphilis, is that we are not testing all of the right people, but because of the challenges associated with testing, we're still determining who are the best people to be tested.

[00:14:40] Host Amber Smith: Well, I'd like to ask you about treatment. Is penicillin effective?

[00:14:45] Elizabeth Asiago Reddy, MD: Penicillin is highly effective, and it is the defacto treatment for syphilis. We have run into some problems recently in the last couple of years with shortages of penicillin. So, the ideal way to treat this is with either one or three shots of penicillin intramuscularly -- and it depends on the stage that the person is in, whether they would require one or three shots -- and that really does an outstanding job of eliminating the infection in virtually everyone. There are rare cases where we might need to repeat treatment or offer a more intensive treatment intravenously. But in the vast majority of people, that is the optimal treatment.

So when we're dealing with a shortage, how do we handle it? We revert to our second line treatment, which is oral doxycycline, and we don't have as good of data for the efficacy over the long run of doxycycline. It definitely is efficacious, but it may be slightly less efficacious compared to penicillin. So it's certainly our preference to use penicillin. There are certain cases of allergy where we need to use doxycycline. And then ceftriaxone is an antibiotic that's in the same kind of general family as penicillin and can be used for people with penicillin allergies, however we don't have a long acting version of ceftriaxone, so that complicates its use for many patients. Because if we were to use that, we would actually have to have people coming back in every day for doses, which is obviously, difficult, inconvenient, and potentially painful since it's an injectable medication.

[00:16:28] Host Amber Smith: You are listening to Upstate's "The Informed Patient" podcast. I'm your host, Amber Smith, and I'm talking with Upstate infectious disease chief Dr. Elizabeth Asiago Reddy, about syphilis.

So after treatment, does that eliminate the trouble? You talked about the latent stage. Does that do away with that, so the threat is gone?

[00:16:49] Elizabeth Asiago Reddy, MD: It does. And I would be remiss to not bring up the fact that part of the reason we know this is because of the Tuskegee experiments, which are horrific experiments that were conducted in the US South on African American people without their knowledge, to see what would happen in untreated syphilis. So this is a situation where, it's one of the many elements that go into mistrust in the US medical system for Black individuals and other people of color, other minority groups. So unfortunately, and tragically, this is how we know this information, that if people are treated, they do not experience these long-term outcomes. And if people are untreated, they have that, like I said, about 30%, 20% to 30% risk of experiencing bad long-term outcomes.

There may be some difference now in modern society, compared to a long time ago because of people's general health and then also because we use antibiotics for a lot of different reasons. So for somebody to reach old age, never having taken antibiotics in the US is becoming less common. So it's possible that someone could be inadvertently treated for syphilis over the course of their lives. But certainly that's not something we would want to take a risk on. And we obviously want to treat people when they need to be treated.

[00:18:14] Host Amber Smith: Well, we don't have a vaccine for syphilis yet, do we?

[00:18:17] Elizabeth Asiago Reddy, MD: We do not. There has been some effort to work on that. I am not aware of anything that looks imminent. Gonorrhea is another story actually, just to mention that anecdotally. There is more work on gonorrhea vaccination, and there's some promise with gonorrhea vaccination.

[00:18:34] Host Amber Smith: You mentioned pregnancy. What happens if a woman gets syphilis when she's pregnant?

[00:18:40] Elizabeth Asiago Reddy, MD: This is very dangerous, and this is one of the things that we're extremely concerned about because we've had a drastic increase in the number of infants who have been born with congenital syphilis or pregnancies lost because of syphilis during pregnancy. So the most dangerous time to acquire syphilis is in the first trimester of pregnancy, with a close follow by the second trimester of pregnancy.

But anytime during pregnancy is dangerous. So within the first and second trimester of pregnancy, the majority of cases without treatment are going to end up being transmitted to the unborn infant, or fetus. And the consequences can be very grave, ranging from loss of pregnancy completely to very severe congenital malformations as well as other chronic infections -- so infections of the bone, infections of the central nervous system. And, the later in pregnancy that exposure occurs, the less likely it is that significant malformations occur, but nonetheless, the infant can still experience very significant signs of infection to include meningitis.

So the results can be really devastating and have very significant long-term consequences for the health of the infant.

[00:20:01] Host Amber Smith: So does the baby get the syphilis through the umbilical cord or during the birth process?

[00:20:08] Elizabeth Asiago Reddy, MD: Either one could occur. When this happens early on in pregnancy, then it's -- because I was mentioning that this is a systemic infection that has a bloodborne component to it -- it would be transmitted directly through the bloodstream throughout the course of the pregnancy, from a parent to child.

[00:20:24] Host Amber Smith: I see. Now, is congenital syphilis appreciably different from just regular syphilis?

[00:20:31] Elizabeth Asiago Reddy, MD: Yeah. Well, many of the same signs and symptoms exist, but they are more severe. Because as you can imagine, if these infections occur while body organs are actually still in the process of being formed, such a severe infection can impact the proper formation of those organs.

So that's why, or one of the reasons why the earlier in pregnancy it is, the more devastating it is because there can be a more significant impact on the actual growth and development of the fetus.

Treatment during pregnancy can prevent these devastating outcomes. So it is extremely important to test during pregnancy. And some of the testing recommendations were revamped when we started to see a rise in numbers.

And in New York State, it does appear that that has made a difference because New York State, I think, did a good job of getting the word out. And testing has increased significantly. So, actually, there should be testing during the first trimester and the third trimester, with an additional recommendation to test during the second trimester if there's anyconcerns about risk. And most people in New York State have just applied that very liberally across the board and tested three times during pregnancy.

I just want to make sure I say that, that hope is not lost. If you test positive during pregnancy, you should be treated, and that will very significantly help to prevent infection or to cure any infection that might have pre-existed.

[00:21:56] Host Amber Smith: So are all pregnant women tested without regard to whether they think they're at risk or not?

[00:22:01] Elizabeth Asiago Reddy, MD: Yes, and that's what I'm saying. So the first and third trimester testing was very strongly recommended in New York State across the board, regardless of risk. And then we had this recommendation for second trimester testing, which could be applied, depending on the potential risk. And I really, I know at Upstate and many of the community OBGyns (obstetrician/gynecologists) that I've discussed this with, they just decided I'm just going to do it in every trimester because I don't know what people's risks are. That is the reality.

We really don't, and that's kind of what I was mentioning before. We don't always do a good job of appreciating what people's risks are. And so even though it may be a small percentage of pregnant patients who are impacted, then it becomes a very devastating situation if we miss even one of those.

[00:22:42] Host Amber Smith: Now, it used to be that the county health department would ask someone who tests positive for syphilis to reveal all of their sexual partners, and then the county health department would try to reach those people and let them know. Do they still do that, do you know?

[00:22:57] Elizabeth Asiago Reddy, MD: That is still done, and it obviously can be a difficult job, but it's very important.

So we do ask people to reveal their sexual partners, and of course we can't know for sure that all the information we receive is accurate. But, overall the tendency has been for people to be concerned about their partners and to provide us with that information. And the health department does this notification anonymously. So if somebody who has been impacted by syphilis themselves wants to be the person who is telling their partners, that's OK. But also it can be done anonymously through the health department.

So somebody might get a call saying, "we have been notified that you were exposed to syphilis." And the recommendation is that if that exposure has occurred within the last 90 days, that person should be empirically treated because it's difficult to know whether somebody might be in the window period at that point and not be manifesting symptoms but have still been infected. Whereas if it's greater than 90 days, then the recommendation is for testing.

[00:23:59] Host Amber Smith: Now, someone who learns they may have been exposed to syphilis may panic. What advice do you offer these people?

[00:24:06] Elizabeth Asiago Reddy, MD: I think it's better to know and be tested and treated if you need to than to not know. So yes, of course it's disconcerting and it's information that is not welcome to, really, anybody. But at the same time, it offers you the opportunity to get the treatment that you need.

[00:24:22] Host Amber Smith: Do they need to stop having any sexual contact until they figure out whether they are infected or not?

[00:24:29] Elizabeth Asiago Reddy, MD: Yes. That is our recommendation for all sexually transmitted infections with the possible exception of human papillomavirus because that is so universal. But with all sexually transmitted infections, we are recommending that people do not have sex during the active phase of their treatment, so until their signs and symptoms have resolved. And we will provide them with information about what we think would be a reasonable amount of time, where they would no longer be likely to spread that to somebody else.

[00:24:54] Host Amber Smith: If someone already had syphilis, are they more or less likely to get it again, or could they get it again?

[00:25:01] Elizabeth Asiago Reddy, MD: They can get it again. There's some information about this from older literature. It's not very clear. There may be some degree of immunity that occurs over time, but it is not, it's definitely not universal. So, people can get reinfected, and we follow their blood tests. There are certain parts of the blood test that will stay stable over time, and there are other blood tests that change over time, as a result of exposure. So we look at those to try and figure out whether someone might have a new infection.

[00:25:34] Host Amber Smith: Well, let me ask you about syphilis in general. Does it occur in outbreaks, like, every generation, or is it just always present?

[00:25:43] Elizabeth Asiago Reddy, MD: It has been largely present, over the long run. In fact, if you look at the numbers, you mentioned 1950. If you look at the numbers pre 1950, we had a ton of syphilis going on, much more so than we do now, because we didn't really know how to test for it, and we didn't have any treatment for it either. And so once we actually had ready access to penicillin, that was when the decision was made to require people to become tested before they married.

And that resulted in a huge drop in syphilis all the way up until about 2013, 20 14. So there was a period of time in the early 2000s when there was a lot of condom use going on, and we said at that point, well, we may be able to eliminate syphilis completely, because it was so low and it was so infrequent. But unfortunately that changed pretty drastically, and then we've had these steady increases ever since then.

So it has been around, and it's very universal. It's around throughout the world, and there's a lot of historical evidence of famous people who either suffered the consequences of the illness itself or of the treatments, which used to be things like mercury and other poisons.

[00:26:56] Host Amber Smith: Wow. Interesting.

Well, Dr. Asiago Reddy, thank you so much for taking time to tell us about syphilis.

[00:27:01] Elizabeth Asiago Reddy, MD: Thank you for having me.

[00:27:03] Host Amber Smith: My guest has been Dr. Elizabeth Asiago Reddy. She's the chief of infectious disease at Upstate Medical University. "The Informed Patient" is a podcast covering health, science and medicine, brought to you by Upstate Medical University in Syracuse, New York, and produced by Jim Howe. Find our archive of previous episodes at upstate.edu/informed. If you enjoyed this episode, please tell a friend to listen too. And you can rate and review "The Informed Patient" podcast on Spotify, Apple Podcasts, YouTube, or wherever you tune in. This is your host, Amber Smith, thanking you for listening.