What’s happened with the recent outbreaks of Ebola and Zika? You might be a tad interested, given that Ebola kills 50% of those infected and Zika wreaks havoc on the newborn children of pregnant moms. Much like HIV, these bugs are two of the heavy hitters in the world of viruses. And they are all transmitted through sex. Great.
To educate my colleagues on these rapacious sexually transmitted diseases, I assembled an A-list of scientists and clinicians, including those on the outbreak response teams, at the American Society of Andrology meeting. It was an incredibly informative half-day symposium that shed invaluable light on these brutal infections.
Ebola
The recent West African epidemic of Ebola was not the first, but it was by far the largest we’ve ever seen. And, according to Dr. Mary Choi from the CDC who was part of the Ebola response team, it is now officially over. This virus normally lives in fruit bats and ascends up the food chain from there. Dr. Choi hypothesizes that infected animals were unknowingly hunted and then touched or consumed by humans, leading to the epidemic. Of serious concern is her recent finding that an Ebola survivor transmitted Ebola by sexual intercourse to a partner over 500 days after his infection cleared! Exactly how long the Ebola lives in semen is still unknown, but appears to be much longer than its lifespan in other body fluids, like saliva and urine. Currently, the CDC recommends barrier-protected intercourse for 1 year among Ebola survivors.
What’s also fascinating is that an Ebola vaccine was “already in the bottle” at the time of the Ebola outbreak, according to NIH virologist Dr. Barney Graham. And, as soon as the outbreak occurred, the vaccine very quickly sped through three stages of clinical trials to determine safety and tolerability. Within 6 months, extremely fast for any drug, it was brought to the front lines of the Ebola outbreak. But alas, the epidemic was under control by the time the vaccine hit the ground and it’s still unclear how effective it really is. For me, based on this speedy and strategic U.S. effort, it was worth every penny of the taxes I paid this year!
Zika
The first Zika epidemic occurred 66 years ago in Nigeria. According to Dr. Gabriela Paz-Bailey of the CDC, the recent epidemic was the fourth one, the largest and is also now over. And because of the ease of international travel nowadays, infected persons were found in 80 countries. The host is a mosquito that transmits the disease similar to dengue fever. The infection causes a typical flu-like syndrome, which is good, but most infections (80%) go unnoticed, which is bad. Although not deadly, Zika infected pregnant women are at very high risk (6-42%) of having fetuses with deadly and often grossly disfiguring abnormalities like microcephaly, club foot and eye and ear defects. Good to hear that Dr. Barney Graham feels that a Zika vaccine is close to ready because this virus is built like others in its class (West Nile and Dengue) and should be amendable to a vaccine. Similar to Ebola, semen is Zika’s last refuge,remaining there much longer than expected after the infection clears, leading to current CDC recommendations of safe sex for 6 months after travelling to a Zika infected area.
Sex
Now that these epidemics have passed, as a sexpert my big question is: What’ sup with the persistence of these viruses in semen? For that we listened to Dr. John Brooks, also of the CDC and an expert on HIV transmission, tell the story of HIV and sex. This is exactly the situation with HIV, which we now have 35+ years of experience diagnosing and treating. At first lethal, HIV is now a chronic condition that is kept under control with a variety of safe antiviral agents. In fact, Dr. Brooks announced the CDC’s recent historic announcement of “U=U” (undetectable=untransmittable) regarding HIV. He explained that when viral titers of HIV in semen are kept low with treatment, no sexual transmission of disease has occurred. Hopefully, our knowledge of HIV can be applied to these two new ugly viruses on the block.
I am so proud of what this team of clinicians and scientists has accomplished in the face of some of the sneakiest and virulent diseases that have faced humanity since the bubonic plague in the 14thcentury. As Tom Hanks said: “A hero is somebody who voluntarily walks into the unknown.” By any measure, they are our public health heroes.
This article first appeared on Dr. Turek’s blog.
