Prior Dengue Infections Likely Cause Worse Zika Infections

April 30, 2016

There are yet new reasons to avoid mosquito bites… and to eliminate mosquito breeding sites. We’ve written extensive articles on this where you can find lots of critical details … see  Continue reading Chikungunya & Dengue Virus Information    and  Continue reading Dengue Fact Sheet 

Now Zika brings new risks.
Dengue infections cause human immune systems to create a special kind of antibodies, called sub-neutralizing antibodies, that persist in our bodies for the rest of our lives … These Dengue virus induced sub-neutralizing antibodies cause every future Dengue infection to cause the patient worse, and worse symptoms, sometimes ending with Dengue Hemorhaggic Fever and possibly death.

In short, the most recent high quality lab studies show that anti-DENV HMAbs, cross-react, DO NOT NEUTRALIZE, and …instead … greatly enhance ZIKV infections … in vitro.

Generally, we paraphrase important scientific articles, but I believe that this article explains itself:

For decades, human infections with Zika virus (ZIKV), a mosquito-transmitted flavivirus, were sporadic, associated with mild disease, and went underreported since symptoms were similar to other acute febrile diseases endemic in the same regions. Recent reports of severe disease associated with ZIKV, including Guillain-Barre syndrome and severe fetal abnormalities, have greatly heightened awareness.

Given its recent history of rapid spread in immune naive populations, it is anticipated that ZIKV will continue to spread in the Americas and globally in regions where competent Aedes mosquito vectors are found. Globally, dengue virus (DENV) is the most common mosquito-transmitted human flavivirus and is both well-established and the source of outbreaks in areas of recent ZIKV introduction.

DENV and ZIKV are closely related, resulting in substantial antigenic overlap. Through a mechanism known as antibody-dependent enhancement (ADE), anti-DENV antibodies can enhance the infectivity of DENV for certain classes of immune cells, causing increased viral production that correlates with severe disease outcomes.

Similarly, ZIKV has been shown to undergo ADE in response to antibodies generated by other flaviviruses. However, response to DENV antibodies has not yet been investigated.

Methodology / Principal Findings
We tested the neutralizing and enhancing potential of well-characterized broadly neutralizing human anti-DENV monoclonal antibodies (HMAbs) and human DENV immune sera against ZIKV using neutralization and ADE assays.

We show that anti-DENV HMAbs, cross-react, do not neutralize, and greatly enhance ZIKV infection in vitro.

DENV immune sera had varying degrees of neutralization against ZIKV and similarly enhanced ZIKV infection. Conclusions / Significance Our results suggest that pre-existing DENV immunity will enhance ZIKV infection in vivo and may increase disease severity.

A clear understanding of the interplay between ZIKV and DENV will be critical in informing public health responses in regions where these viruses co-circulate and will be particularly valuable for ZIKV and DENV vaccine design and implementation strategies.

Continue reading to find out how to STOP Dengue,  Chikungunya,  and Zika viruses … and protect yourself  and loved ones… at    Continue reading Dengue Fact Sheet 

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Feel free to copy while giving proper attribution: YucaLandia/Surviving Yucatan.
© Steven M. Fry

Read-on MacDuff . . .

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7 Responses to Prior Dengue Infections Likely Cause Worse Zika Infections

  1. sdibaja says:

    Thanks for keeping us informed.
    My wife and I got Chikungunya in October 2015, we are mostly over it just now. Does this new information have a bearing on Chikungunya?
    Thanks, Peter in Baja

  2. Thank you for this – I think!
    I had dengue in November and it was pretty awful. It left me with a light-headedness that made it difficult for me to wak without a cane. As that began to lift and I could walk better and better, I got the flu for the first time in nearly forty years.
    Locals of the village I had been in told me it was my weakened immune system that made me more sucestible to the flu, and I am guessing they are right.
    In any event, the second bout of illness combined with high fever has left me again with that light-headedness, and it has continued for three months.
    I now preach to the masses (well, not quite) about mosquitos and mosquito borne illnesses and will soon have a blog post of my own about this,

  3. Susan Swanson says:

    Thank you for always keeping us well-informed on a wide variety of issues.

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