11 things we learned about Zika from a top disease expert

The top disease expert in the U.S., Tom Frieden of the Center for Disease Control, popped down to Miami last week for the CityLab conference to talk Zika and other diseases.

While here he gave a super honest, interesting talk about where he sees the Zika virus and other infectious diseases heading — and what he learned from the experience here in Miami this year.

Even a bottle cap full of water can be a mosquito breeding ground.

How small can a pool of water be and still be a mosquito breeding ground? Frieden gave examples: Bottlecaps, bromeliad plants, a coffee cop left on the street, and even the top of that coffee cap. That’s really, really small.

Our mosquito control found hot spots in surprising places.

Construction sites, with all their standing water, have been a big problem in Miami, so the mayors are working on imposing regulations to promote drainage at construction sites. Elevator pits are also a big problem.

An Aedes Aegypti mosquito is really good at biting people.

In one blood meal, it bites an average of four to five people. And you won’t feel it when it bites you.

But it doesn’t go very far.

They fly about 400 feet in their whole lifetime, which is about a month.

We did really well fighting Zika in Wynwood. But even doing everything right isn’t enough.

“In Wynwood they did everything possible. They have an excellent mosquito control program here, one of the best in the world,” Frieden said. “They had more than 100 teams working at one point.”

But they still had new cases pop up.

“The really important experience with Wynwood is that despite doing everything right, they still had very high mosquito counts,” he said.


Insecticides, while controversial, are really effective.

They’re a last resort option for the CDC, but “literally within a day [of spraying in Wynwood], the mosquito counts went to zero” and “90 percent” of mosquitoes in the traps were killed, Frieden said.

Those numbers still haven’t rebounded, nor have there been new cases in Wynwood.

But we simply don’t have the technology to totally stop Zika.

“Here’s the plain truth. Zika and other diseases spread by Aedes Aegypti are really not controllable with current technologies… we will see this become endemic in the hemisphere,” he said.

A vaccine could accomplish this, but there isn’t one yet.

It will be several more years before we have a vaccine.

“With Zika and viruses like Zika, our immune response to it is very strong,” which makes a vaccine a strong option.

It usually takes five to 10 years to bring it to market, Frieden said, but he said he hopes the Zika vaccine can be ready in two to three years.

The CDC would be stoked if they could wipe out Aedes Aegypti.

Although there are real concerns about eliminating certain species, Frieden says they don’t apply to Aedes Aegypti.

“It’s an invasive species. It’s not native to this hemisphere,” Frieden said.

It also carries many other diseases, including malaria, which kills 400,000 people a year.

Its elimination wouldn’t have much of an effect on bird and bat populations because there are many other species of mosquitoes out there, he said.

“Zika is going to cause birth defects and tremendous disruption… for years to come. If we could get rid of this mosquito, I would be very happy,” he added.

Zika takes a long time to show its worst effects, which makes it hard to get money to fight it.

Congress failed to pass money for Zika prevention or treatment for months. It pretty much totally stalled while the parties bickered over the funding package.

“Zika was a part large problem because it was theoretical for people. Second it was babies who were going to be born six to 9 months from now” who would show the effects.

But the fact that this prevented us from taking any action taught Congress a lesson, Frieden thinks. Also it probably changed their thinking on emergency funding — right now the CDC has $2.5 million for urgent needs in a budget of $14 billion. Frieden says that needs to grow a lot and quickly.

This is the new normal.

Outbreaks like this year’s Zika outbreak are happening more and more often.

“Our emergency operations center has been activated 91 percent of days I’ve been director. This is the new normal,” Frieden said, adding that the CDC now expects to find at least one new pathogen a year.

“No one would have predicted Zika. We’ve never before had a mosquito-borne cause of birth defects… that is sexually transmitted as well.”