Lindsay C. Malloy: While pregnant with my second child, I had a false positive Zika test
My experience isn't rare, she writes, and we need more funding for better testing and support
Editor’s Note: Lindsay C. Malloy is a psychology professor at Florida International University. The opinions expressed are her own.
I live in Miami. I’m pregnant. I tested positive for the Zika virus.
At least that’s what I was told, and that’s what I believed for six long, painful weeks. They were excruciating weeks of waiting for a special test that only the Centers for Disease Control and Prevention can do to confirm whether I had, in fact, contracted Zika during the beginning of my first trimester – a crucial period of time for a fetus’ brain and nervous system development.
I endured over 40 anxiety-provoking days carrying my second baby, one that I wasn’t sure I would be able to keep, before learning that my test result was – thankfully – a false positive.
I am a scientist. I’ve published many scientific papers. I’ve never published anything about my personal life, and even now, I am not entirely comfortable with the idea. But as Zika continues to spread, other women and families should be aware of what my family went through as they navigate testing and diagnosis themselves. We could have known more. My husband and I could have avoided a living hell during what should have been a joyous time in our lives.
Facing this situation hits home for me in more ways than one. My husband is an entomologist who has done mosquito research. We knew how to protect ourselves while trying to conceive, and the critical importance of doing so. I had been reading about Zika for months, feeling heartbroken for pregnant women in Brazil and worried that the virus would travel to Miami (which, of course, it did).
But at 36, I didn’t have the luxury of waiting for a Zika vaccine before trying for another baby so we took extreme precautions from day one. We wore loose-fitting long sleeves and long pants, and socks and shoes, every day – with DEET on our rare bits of exposed skin. We severely limited our outdoor time. If you’ve ever been to Miami in August, you know that the sweat pools in your lower back within moments of stepping outside, even when standing still in the shade, so imagine chasing after a toddler with almost every inch of your skin covered in 90 degree heat with 90% humidity. We were a spectacle, drawing stares at our local park, but it was worth dramatically decreasing our quality of life, we thought, in order to protect ourselves from Zika.
I found out that I was pregnant with my second child very early on. We were thrilled. Despite our extreme precautions, I had my blood drawn for my free Zika test just one week later.
I was shocked to receive the call from my OB – my Zika antibody test was positive, meaning that I had likely been exposed to the virus in the past 12 weeks. My entire world stopped. Through sobs, I said that my positive result simply wasn’t possible. We had made our lives miserable to (successfully) avoid mosquito bites. We had never traveled to the active transmission zones. It made no sense.
There was more. Because of potential “cross reactivity” with other flaviviruses, the antibody test is not enough to confirm a past Zika infection. Only the plaque reduction neutralization test (PRNT) can do that with certainty. My blood was sent to the CDC for a PRNT right away, while my husband and I racked our brains to find out what could have gone wrong. We concluded that he must have contracted Zika and transmitted it to me sexually. A few weeks before – the weekend that I became pregnant, as it happens - he had some of the symptoms – joint pain and feverishness. We tried to get him tested for Zika to confirm our suspicions, but we were told that the health department would only test pregnant women – even though Zika is known to be a transmittable disease.
Testing at a private lab could cost up to $800. Based on our precautions and the steep cost, we did not have him tested. But now, we inferred that it was Zika, and that he had given it to me at the worst possible time in terms of fetal development – in the first trimester. The doctors told me that false positives were possible. They implored me to wait for the test results from the CDC before deciding whether or how to proceed with the pregnancy. This gave me a glimmer of hope, which at the time I considered dangerous.
I cried through my first ultrasound and my husband looked at me worryingly when the technician asked if we wanted photos. I didn’t want to look at the screen or get “attached” to the idea of being pregnant. We were considering an early termination. We met with a group of specialist OBs for a “Zika consultation.” Another traumatic ultrasound. All we heard from doctors was choruses of, “We just don’t know yet … the virus is so new … we need more data …. no one knows…” I had been reading the empirical research for months so I knew that there was no clear prognosis. While it is certainly not a given that Zika infections during pregnancy result in birth defects, we knew there was a fairly high chance that our baby would be affected in some way by the virus, potentially catastrophically.
Throughout this horrible time, I couldn’t stop wondering: What were the chances of a false positive? One in 100? One in 1,000?
Turns out, they were much higher than that. A few weeks later I found data published by the CDC showing astronomically high rates of false positives on the antibody tests . Specifically, in a sample of 222 pregnant women who tested positive on the antibody test (like I did), PRNTs revealed that 38% were actually negative for Zika. That’s a more than 1 in 3 false positive rate! Another 10% tested positive for dengue fever instead of Zika. When I shared these data with my doctors, they said they had not seen them.
Eventually, my PRNT came back – six weeks to the day from receipt of my false positive result and over seven weeks from when my blood was drawn. I was over 12 weeks pregnant by then. I could see from the test’s date of completion that it took almost a week for the results to travel from the CDC to the health department to my doctor and finally to me. The waiting was agonizing but the reality is that this delay could mean the difference between a woman being able to terminate an affected pregnancy – if she so desired - or not. Despite the fact that pregnant women’s tests are supposed to be prioritized, my husband’s tests came back weeks before mine.
My exasperating and traumatic experience was, at least in part, a failure of our government to fund and prioritize science and public health – to appropriately support the CDC, which has been working fervently to understand Zika and its effects. In February 2016, the Obama administration requested $1.9 billion in emergency funds to combat the Zika virus – six months before active transmission began in Miami. They knew it was coming. They needed money for mosquito control, the education of health providers and citizens, and for testing and diagnosis. Congress did not fund a Zika bill until late September 2016 – a full two months after active transmission began. Republicans had repeatedly inserted “poison pill” legislation into the Zika bills, including legislation targeting Planned Parenthood.
If Congress had empowered the CDC to establish more efficient reporting systems, we might already have better and more refined tests. The Zika virus is here to stay and scientists and public health officials need continued funding to learn more so that other vulnerable pregnant women do not find themselves in my position. Instead, Congress played a political game with our lives and the lives of other families, and to me, it is absolutely unforgivable.
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We are having a daughter in June. We are extremely thankful for her health and grateful that this saga is behind us. But the threat is not really behind us – there are still months ahead of protecting myself from mosquitos potentially carrying Zika. I think about it – and about all the many people similarly at risk – every time I step outside.