The Zika virus and Chester County

by Nathaniel Smith, The Times of Chester County, 9/1/16

Getting rid of standing water is more effective than spraying

News has come around lately that “Pennsylvania Is Now One Of The Top States With Zika Virus ” (Phoenixville Patch, 8/23/16). Currently PA ranks 5th in the number of diagnosed Zika cases. Of course, no one knows how many undiagnosed cases there are anywhere.

Quick quiz: how is Zika spread? If you answered “by mosquitoes,” you’re only half right. It’s our fault too.

It’s important to focus on this note in the article: “All of the cases were travel-related, according to the Centers for Disease Control and Prevention.”

That means no human has acquired Zika from a mosquito in PA. Although the prime mosquito host for Zika, aedes aegypti, does exist in Pennsylvania, it doesn’t do well this far north (yet).

The fact is that Zika is spread not only by mosquitoes but also by people, whether through sexual contact (CDC offers explicit advice on this aspect) or from carrying the virus (usually without symptoms) and being bitten by a mosquito that in turn bites someone else, who thus acquires the disease. The aedes albopictus mosquito, often called “Asian tiger,” has become very numerous in PA but fortunately does not seem to transmit Zika very well (yet).

Spraying pesticides is a limited, short-term fix that leaves many adult mosquitoes alive and does not affect eggs and larvae but harms many forms of life and can lead to acquired immunity. Mosquitoes breed over 500 times faster than people, so they will become immune to whatever we do against them much faster than we can evolve to resist them. Mosquitoes in Puerto Rico and Florida are already becoming resistant to permethrin, the standard anti-mosquito pesticide.

This is all not good news, except that in PA we do have some time to get ready for present and future mosquito-borne diseases….

read more at The Times of Chester County

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Inovio Pharmaceutical’s DNA Vaccine for Zika Virus Induces Robust Immune Responses in Preclinical Study

Inovio Pharmaceutical, 2/17/16

Biotech begins clinical manufacturing; expects to test Zika vaccine in humans in 2016

PLYMOUTH MEETING, Pa., Feb. 17, 2016 (GLOBE NEWSWIRE) — Inovio Pharmaceuticals, Inc. (NASDAQ:INO) announced today that preclinical testing of its synthetic vaccine for the Zika virus induced robust and durable immune responses, demonstrating the potential for a SynCon® vaccine to prevent and treat infections from this harmful pathogen. Health authorities have observed neurological and autoimmune complications potentially associated with Zika virus, including microcephaly in newborns and Guillain-Barre syndrome. Inovio is developing its Zika vaccine with GeneOne Life Sciences (KSE:011000) and academic collaborators.

Read more at Inovio Pharmaceutical. Read about the current clinical trial in Puerto Rico here.

What we can learn from anti-zika spraying

by Nathaniel Smith, Politics: A View from West Chester, 8/9/16

Zika virus is transmitted by mosquitoes and people.

So, health authorities have been working on the twin challenges of eradicating mosquitoes and educating people.

Transmission of Zika virus from mosquitoes to people (and vice versa) in the continental US has occurred only in one small tropical enclave: a square mile (or now it seems even less) of Miami. Pennsylvanians might worry about catching zika from travelers returning from the Rio Olympics but not from mosquitoes this summer so far north. (1)

However, we should be worrying about the effects of being sprayed with pesticides, of which there is really no safe level for the environment and human exposure.

As someone involved in the current campaign to cut down on both mosquitoes and pesticide spraying in West Chester, I think we can learn a lot from zika, even if it is not currently being transmitted by mosquitoes anywhere near us.

Many insects, like the viruses that attack the human body, reproduce quickly and can develop resistance to whatever we throw against them. As doctors turn from one antibiotic to another to find one that still kills a given virus, so health officials experiment to see what still kills different mosquito species.

The Aedes aegypti mosquito, the chief transmitter of zika, is particularly problematic for traditional mosquito elimination programs and the standard anti-mosquito pesticide permethrin, a pesticide usually applied from ground-based equipment such as trucks. (2)

Aedes aegypti has been acquiring immunity in Thailand (3) to permethrin and even to DDT (which was banned in the US in 1972 after severe impacts such as almost driving our national bird into extinction); and similarly in Mexico (4) and, more recently, in Puerto Rico (5) and now Florida. (6)

As time goes on, scientists have to look farther up the pesticide chain—with further likely risks—to find more effective pesticides. This is not good news….

aerial spraying

read more and see end notes at Politics: A View from West Chester, 8/9/16

Zika Surge in Miami Neighborhood Prompts Travel Warning

By PAM BELLUCK, New York Times, AUG. 1, 2016,

This excerpt details why we find reliance on pesticides to solve mosquito problems not only undesirable but potentially unreliable:

…Dr. Thomas R. Frieden, the director of the C.D.C., said that the Aedes aegypti mosquito, which transmits the Zika virus, has proved to be a wily adversary in Wynwood, a crowded, urban neighborhood in north Miami where all the cases were found. The mosquito may be resistant to the insecticides being used or may be able to hide in standing water.

“Aggressive mosquito control measures don’t seem to be working as well as we would like,” he said in a press briefing on Monday.

The authorities had expected additional cases of Zika infection linked to the neighborhood, he said. But officials were particularly concerned by indications over the weekend that “moderately high” numbers of Aedes aegypti mosquitoes and their larvae were still being found in a one-square-mile section in Wynwood, an area of warehouses, art galleries, restaurants, bars, apartments and condominiums….

read the full article at New York Times