Saturday, September 3, 2016

Zika update 9-3-16

Electron microscope image of Zika virus. Credit:
Purdue University/Kuhn and Rossmann research groups via The Verge


This has been a pretty bad week for news on Zika virus overall, but there has been some good news.

Among the bad news, the announcement that the limited funding to fight Zika virus in the US is almost gone was the most disheartening. Earlier this year, the CDC was allocated $222 million to fight Zika as a temporary measure until a larger funding bill was passed by Congress. However, that bill has been tied up in Congress as there is a fight over an attempt to prevent any funding from going to Planned Parenthood. Given that Zika can cause severe birth defects if a pregnant woman catches it, it only makes sense to have all options on the table for dealing with this virus. Right now, the CDC has spent $194 million of what they have. President Obama has shifted more funds to vaccine development, but this is only a temporary measure as well. Congress is set to vote on the funding bill again once they return from their recess, so hopefully they can come to a compromise and this vital funding can be dispensed.

Meanwhile, the outbreak in Florida has continued and health officials there have reported more cases of local Zika transmission and also detected Zika in the local mosquito population. Taken alone, this isn't terrible news. However, due to not only the recent findings that Zika can be passed from an infected female mosquito to her eggs, the recent hurricane that dumped a lot of water on Florida, and the continued fight against deploying the genetically engineered Aedes aegypti mosquitoes that pass on a lethal gene to their offspring, this has significant implications for the epidemiology of Zika in the US. Worldwide, the vertical transmission can help explain the spread of this virus and inform the decisions of researchers and healthcare officials in combating this virus. Because the virus can survive in its vector, reducing the vector population is one of the best ways to combat it. The GE mosquitoes are very effective at reducing the vector population without needing pesticide applications that can sometimes have unintended effects, such as the accidental killing of bees in South Carolina recently.

Worldwide, there is more bad news for Zika. A large outbreak has begun in Singapore with over 150 testing positive for the virus and likely many more are infected. There has also been a case of travel related Zika that made it to Malaysia from Singapore. Officials are taking steps to try and limit the chance of local transmission of Zika, but since the vector is endemic, it may just be a matter of time before it spreads, much like what happened in Florida.

The WHO has also recently expanded the recognized range of conditions caused by Zika to include other birth defects. The WHO recently held a press conference on it that they shared to Facebook. Making matters worse, new research has linked Zika virus to a worldwide increase in 
Guillain-BarrĂ©. 

But the news on Zika this week hasn't been all bad news. I recently mentioned a new study that described an improved method for screening existing compounds for activity against Zika. This is a promising approach to not only quickly screen drugs we already have, but also newly developed drugs to combat this virus.

Also on the good news side, Cuba is reporting great success in controlling Aedes aegypti and by extension Zika. As soon as Zika started spreading to the Caribbean in February, the Cuban government immediately took steps to combat the vector. They began spraying inside peoples homes and taking steps to eliminate standing water where the mosquito can breed. Their approach may not work in other countries as the government is led by a single party and has great control over the population. This can be seen with what has happened with attempts to control the vector in the USA; deployment of an effective and safe control measure being blocked by protesters.

Perhaps if the US had started trying to control the vector back in February, we could have avoided the outbreak that we have now, but we waited until the virus had local transmission before much of the general population agreed it was a problem. Hopefully, we can take decisive action now and stop further spread of Zika and complete work on a vaccine. But we need funding to do so.