Bite!!! Life in a Warmer, Wetter World

Bookmark and Share

Link suite overview: On vector-borne disease and climate change, connecting the infinitesimal and the invisible, Dopey Does DDT, the need for ecosystems thinking & bugs gone borg

Links become part of the TrackerNews searchable database.

It is a midsummer night’s feast and we are on the menu. Nibbled and sipped by winged vampires and  blood-sucking squatters, we scratch, swat and fret. But the bugs, annoying though they may be, are merely messengers. Virus, bacteria, rickettsia, protozoans and helminths—those are the ones turning the whole predator / prey equation on its head.

From a safe distance, preferably behind screens, pants tucked sensibly into socks and doused in parfum-de-DEET, the elegance of the big picture is both undeniable and astonishing. This is the web of life at its webbiest, connecting the fates of the infinitesimal to the invisible—shifts in weather patterns, changes in climate—and everything in between.

A bird flies a little further north than usual one spring, staking out territory in what, for it, is literally new territory.  A warmer, more humid world has brought earlier thaws and later freezes to this particular neck of the woods. Which is also  good news for the bird’s passengers: the ticks on its body, mites on its wings, virus and bacteria in its blood. Occasionally even something as big as a snail manages to survive the journey, berthed in a bird’s gut, likely carrying a parasitic payload of its own.

For everything we can see changing in the landscape—tundra to forest, swamp to sea, lake to desert—there is so much more going on at the edges of detection.

A deer tick finds itself in grasslands favored by voles rather than the forest, where white-footed mice rule the leaf litter. But a blood meal is a blood meal. So the tick latches on and borrelia—the bacteria carried by the tick that causes Lyme Disease—sets up shop in a new animal host. This is the Disease Cycle as jazz, constantly riffing theme and variation. Innovation as making do.

While global trade and travel do a mighty job of mixing up the pot, speeding the spread of pathogens and invasive species, climate change alters the basic recipe. How do you restore a tundra whose permafrost has melted? Or a rainforest weakened by repeated periods of drought? How do you make plans for a world in transition to a “new normal”?

Pollution, carbon emissions, deforestation—all at least hold out the possibility of reversal: things can be done, if only we would do them.

Climate change is a dragon awakened.

BITE!!!

“Bite!,” the new link suite-story on the TrackerNews aggregator, surveys a variety of vector-borne diseases, all on the rise due, at least in part, to climate change: Cold-blooded insects prefer a warmer, wetter world.

It is not their only stroke of luck. Tight budgets in the US have put mosquito abatement districts in the political cross-hairs as an easy target for “saving” taxpayers money, no matter the expense of taxpayer illness. Lose the public abatement districts and there would be no coordinated surveillance for West Nile virus. Or for dengue, which has recently established a foothold in Florida decades after it was eradicated. Or for the next headline horror—chikungunya?—on the horizon. The standard bureaucratic spin about”the best science available” falls flat when the “best” is barely any at all.

Bugs—and the bugs they carry—won’t disappear even if the data do.

Funding actually needs to go up. Way up, according to Peter Hotez, president of the American Society of Tropical Medicine and Hygiene, dengue is “a bigger threat than many of the biodefense pathogens that we’re spending huge amounts of money on. Dengue and other vector-borne diseases are a true homeland security threat.”

Really, though, they are a global security threat and public health disaster. For every breakthrough…

…there are setbacks.  Babesia, a parasite carried by ticks—including the tick that transmits Lyme Disease—causing a malaria-like illness, is on the ascent. Diagnosis and treatment an be tricky. There is no vaccine. Further complicating matters, a single tick can deliver both babesia and borrelia.

Humans are hardly the only animal hosts under assault:

  • Moose are facing a similar fate from “winter ticks.” These are ticks that latch onto to moose in the fall, burrow into their coats and feed all winter. It used to be a moose might pick up 30,000 ticks, a horrifying but survivable number. But a shifting climate means snow melts earlier. Ticks fall off onto dry ground in the spring, allowing more to survive. Their breeding season is longer, too. Now “ghost moose” have been found with over 100,000 ticks. Like the baby fish, they are being bled to death.

****

****

DOPEY DOES DDT

Meanwhile, cases of  leishmaniasis, a parasitic disease carried by sand flies, are also on the rise, bedeviling everyone from soldiers in Afghanistan to the  beleaguered residents of the world’s newest country, South Sudan. Efforts in India to eradicate the disease by 2010 failed spectacularly.

Yet simply getting rid of sand flies could lead to other problems: As larvae, they eat garbage.

Single-focus wars-on-fill-in-the-blank-disease rarely work (only smallpox and the cattle scourge rinderpest have been effectively wiped out, and notably neither were vector-borne).

****

In the early 1940s, the Walt Disney Company produced a series of short educational films, among them, “Winged Scourge,” in which the Seven Dwarfs (yes, those seven dwarfs) take on Public Enemy Number 1: the Mosquito—”wanted dead or alive”… (HT to epidemiologist and author of the marvelous Aetiology blog Tara C. Smith)

Wrapped in gobsmacking kitsch is a matter-0f-fact portrayal of then state-of-the-art pest control: drain wetlands, coat breeding ponds with oil and waterways with Paris Green, spray copious amounts of insecticide (likely DDT, given the time frame), put up screens, seal building cracks and use bed nets. It worked, too, at least for a while,  if you don’t count the cascade of eco-disasters that followed.

****

****

Not only is there a need for an “ecosystems thinking” approach, but one that can accommodate fast-changing landscapes. What was, isn’t any more. What is, won’t be for long.

The climate dragon is awake, scattering clouds of mosquitoes, flies, fleas, mites, ticks and lice as it yawns, stretches and shakes off a millenia-long slumber.

RELATED:

  • Under Our Skin, documentary by Andy Abrahams Wilson chronic Lyme Disease / website

Vaccines!: The Good Fight, Funding Struggle, Breaking the “Cold Chain” and a Bit of Biomimicry

TrackerNews “Tumblr” posts are short intros to new link suites on the aggregator.  However, the Vaccines! post ran a bit longer than usual, so we have decided to reprint here as well. – Ed.

Few things bring as much “bang for the buck” in global public health as vaccines. It is simply a lot cheaper to prevent a disease than to pay for treatment and the cascade of downstream costs (orphaned children, food for people too ill to farm or keep jobs, etc.) Yet in the current economic downturn, funding cuts have forced even high profile programs such as polio eradication and HIV vaccine research to make some fraught decisions about which initiatives to pursue and which to drop.

Which isn’t to say there isn’t a lot of money vaccines. Sales jumped nearly 30% between 2007 to 2009, from $18.5 billion to $26 billion, with flu jabs accounting for $5 billion, and Gardasil, Merck’s controversial vaccine designed to prevent cervical cancer, hauling in just over $1 billion. Per year.

Some vaccines provide subtle but significant side-benefits. Use of vaccines against diarrheal and pneumococcal diseases, for example,  have led to a decrease in antibiotic resistance in local populations. Fewer antibiotics overall are needed, which cuts down on the opportunities for resistance genes to evolve. Those who need antibiotics are more likely to actually benefit from them.

Likewise, GALVmed’s focus on livestock and poultry vaccines not only benefits animals, but also the hundreds of millions of rural poor in developing countries who rely on them for food and income. A measly 5%  of international aid goes toward agriculture, yet it is much cheaper to help people grow their own food than to ship stockpiles of emergency grain.

Breakthroughs in vaccine delivery and storage have significantly increased the effectiveness of immunization programs. Breaking the “cold chain” has become a rallying cry for a raft of new technologies. Traditionally, vaccines have had to be kept chilled throughout the entire journey from high-tech lab to off-the-grid clinics. A new bi-chambered syringe, which keeps the vaccine in a freeze-dried form until needed, may change that.

Vaccines with longer shelf lives should also cut down on costs. An estimated $260 million worth of swine flu vaccine had to be thrown out in the U.S. when it hit its expiration date over the summer.

Research continues on “edible vaccines,” a.k.a. “plant-based pharmaceuticals,” a.k.a. “molecular farming.” Although not quite the headline-darling they were five years ago, in large part due to concerns over GMOs, 20 years of research has more than proved the concept. It is possible to snack one’s way to immunity.

Since human researchers have yet to invent anything Nature doesn’t already do at some level (see “jumping genes), it begs the question whether foods naturally provide a degree of vaccination. For example, could this be a contributing factor for why not everyone gets sick drinking contaminated water? Is it possible that plants, which are known to take up pathogens via water (e.g., e.coli in lettuce), slurp up low levels of local germs, triggering an antibody response in those who eat them?

Of course, this is just speculation. But if anyone out there knows of any research, or is inspired to do the research, please keep us posted at TrackerNews. We love this sort of thing. Nobody does balance better than Nature.

The link suite includes articles and videos on:

  • Breaking the “cold chain” with a smarter syringe
  • Malaria vaccine possible by 2015
  • Vaccinating the middle man: protecting robins against West Nile and mosquitoes against plasmodium
  • Dengue trials for an all-four-strains vaccine in Australia
  • Why the money might run out before polio does
  • Hurdles slowing down progress on TB jab
  • Fungus to fight fungus – vaccinating trees
  • Is eradication futile?
  • and more…

All links become part of the TrackersNews’ searchable archive.