What Are the Implications of Prolonged Zika Virus RNA Shedding?

Marta G. Cavalcanti, MD, PhD, physician at Infectious Diseases Clinic, Hospital Universitario Clementino Fraga Filho, UFRJ, Brazil, discusses how the period of RNA shedding correlates with the severity of complications associated with mono- or coinfection in Zika patients.

Interview Transcript (slightly modified for readability)

“Our results are suggesting that the longer the period is that you have RNA shedding—even in your blood samples or urine—you have more chances to have prolonged disease. There is a particular difference when you take a look in individuals with only Zika virus infection and individuals (as in my country where you have more than one arbovirus circulating at the same time) [that] have combinations of infections and in this group that we are calling the “coinfected group,” they have a different pattern in terms of disease development. What we saw is when you have Zika virus infection, only [Zika] infection, you can prolong the time of RNA shedding, but most probably you would be asymptomatic and the time for disease development actually is similar to any other groups that interrupt or just don’t have longer RNA shedding.

But when you have another infection, simultaneously, or even subsequently, you can see that RNA shedding is parallel with your development of disease and it might be also important for severity. For instance, in cases where you have immunosuppression—and that’s when you are worried—you maintain your RNA shedding for a very long time and that is actually occurring at the same time that the patient manifests no improvement in their disease, or symptoms. For instance, if you have a patient with liver transplantation or renal transplantation, you are going to see that they’re having loss of liver function or renal function.

If you have a patient that is immunosuppressed by drugs, like patients with inflammatory, chronic diseases, or collagenosis, they are not improving their symptoms, and it takes longer for them to stabilize it. Mortality was not analyzed in this particular study, but we have seen that it might be important to make the analysis as that as an outcome in particular groups, especially the ones with severe comorbidities, such as transplant patients, individuals with cancer, HIV patients (which is another particular story), and also individuals with immunosuppressive disease of other etiologies.”