Saturday, September 22, 2012

West Nile Virus and how to avoid it:  published in the Sun Sept. 22, 2012


Evil, blood-sucking pests, mosquitoes are responsible for more human misery, disease, and death than any other insect.  Yellow fever, malaria, dengue, encephalitis, and now West Nile virus are all transmitted by mosquitoes.  As someone who has suffered a bout of malaria, I would shed no tears if mosquitoes were an endangered species, but alas, they are thriving.  (To be fair, mosquitoes are an important source of food for bats and birds, but we are not discussing that virtue today.)

 

Texas is currently the epicenter of a small epidemic of West Nile disease; more than 1200 confirmed cases and 50 deaths in Texas this year.  Forty percent of all the cases in the US have been in Texas.

 

Mindy Powell, a registered nurse, told me about her 80 year old relative in the Dallas area who recently died of the most severe form of West Nile, called neuroinvasive because it attacks the brain.  One day this active outdoor enthusiast and fisherman thought he might be getting a cold, but rapidly worsened.  He called his daughter to come over.  By the time she arrived, her father was unable to walk.  At the emergency room he became confused and lost consciousness.  After three weeks in the ICU on a ventilator, he passed away.

 

Dr. Virginia Headley, epidemiologist with the Williamson County and Cities Health District (WCCHD), stated that six people in Williamson County have had the neuroinvasive form of West Nile this year.  Of those six, one died and two formerly independent elderly adults are in nursing homes recovering.  More commonly, people infected with West Nile virus get a fever and other symptoms, but the brain is not affected, and they eventually recover.

 

For every person who is diagnosed with West Nile fever, at least 4 others are infected but never know it because they have no symptoms.  We know this because donated blood from healthy people is checked for antibodies to the virus.  Between 2003 and 2008, the CDC analyzed all the donated blood in the US and discovered that about 1% of the population had already been infected.  A study in Houston found that among homeless men who had lived outside for a year, more than 16% had developed antibodies to West Nile.  Once you have had the virus and recovered, you are probably immune, but it might be too soon to know if the immunity lasts for life.

 

So what can we do to control this situation?  Pesticides can be sprayed in an emergency, but pesticides only knock down the adult mosquito population temporarily and are not practical in rural areas.  Pesticides don’t get at the root cause which is too many nice breeding places for mosquitoes.  As Dr. Chip Riggins, executive director at the WCCHD, explained, “Aerial spraying is an adjunct to other things.  You can spray all day long and if you don’t have the public helping, it won’t work for long.”

 

Last week’s rain provided lots and lots of stagnant water to breed mosquitoes.  Some kinds of mosquitoes can go from an egg to a biting adult within 5 days, especially in warm weather, so we will start to see mosquitoes now from the recent rains.

 

I decided to take a trip around my house to see if I could find any breeding areas, supposing of course that I would not, because who wants to think that her own home is a public health hazard.  Immediately upon stepping out, I saw that the birdbath was teeming with wiggly mosquito larvae.  Disgusted, I dumped it out.  Next I found a bucket with water in it and a saucer under a plant.

 

Deborah Marlow, deputy director of environmental health services, has been interested in ecological methods to control pests since her college days.  Deborah studied mosquitofish, a minnow also known as Gambusia affinis, as predators of mosquito larvae.  A Gambusia minnow can eat its body weight in larvae every day.  A dozen mosquitofish can keep an abandoned swimming pool mosquito free for months.  My friends Bob and Janine Hall also use mosquitofish in their aquaponics gardens and horse troughs.  Janine said she bought the minnows at McIntire’s nursery several years ago and doesn’t even have to feed them.  They not only live off the mosquito larvae but they reproduce prolifically.  Whenever the Halls build a new aquaponics bed, Janine just dips some more mosquitofish out of the horse trough.  The mosquitofish are not sensitive about water quality either.  The only time the minnows ever died was the year it stayed below freezing for three days straight and the horse trough froze into a solid block of ice.

 

Mosquito dunks are another way to control larvae in standing water that cannot be drained.  The dunks contain spores of Bacillus thuringiensis israelensis, called Bt for short.  When the spores are eaten by a mosquito larva, a toxin paralyzes the larva’s intestine, causing it to die of starvation or septicemia.  Luckily, birds, fish, and animals are completely resistant to the toxin in Bt.  In 1959, an intrepid group of volunteers ingested a gram of Bt daily.  Some of the volunteers inhaled an additional dose as well.  After five days of this regimen all the volunteers were completely unaffected.  I don’t think you would be allowed to do an experiment like that these days.

Mosquitofish in a pond at McIntire's Garden Center

Clint Hawes at The Feed Store demonstrating mosquito dunks

Bill Stump checking a gutter for standing water

 

Tips for Avoiding West Nile Infections (from DSHS and CDC websites)

 

1.  Use insect repellent containing DEET, picaridin, or oil of lemon eucalyptus.

 

2.  Dress in long sleeves and long pants when you are outside.

 

3.  Stay indoors at dusk and dawn, when mosquitoes are most active.

 

4.  Drain standing water where mosquitoes breed.  Common breeding sites include old tires, flower pots, and clogged rain gutters.  Toys, buckets, and tarps that aren’t pulled taut can also collect water. 

 

5.  Make sure mosquitoes cannot enter rain barrels.  Use mosquito dunks or Gambusia minnows in water features and ponds.

 

6.  Install or repair screens on open windows.

 

7.  Remove brush and debris where adult mosquitoes hide.

 

Saturday, September 8, 2012

OUR Ecovillage

Published in the Sun September 8, 2012


Forced to survive on the produce from my own vegetable garden, I would certainly starve to death within one season.  I’ve never plucked a chicken, or butchered a hog, or even milked a cow with any success.  So why is the idea of homesteading so appealing to me, and to so many of my grocery store dependent peers?  Why do city dwellers yearn for a piece of rural property with poultry and fruit trees and a family harmoniously doing rustic chores?

 

My completely unsubstantiated theory is that humans have an evolutionary need to band together in small groups and work for food.  If you live in the city, food is everywhere; more food than you could possibly eat.  The thrill of the chase is gone.  Where is the satisfaction in buying a hamburger at a drive-up window?  By relying on agribusiness for nourishment, oil companies for energy, and Hollywood for entertainment, we have accepted the role of hungry baby birds, helplessly waiting with open mouths to devour what others regurgitate.

 

True self-sufficiency is not realistic in modern society (thank goodness) but we still have an urge to work together with friends and family; to plant, to build, to sweat, and to high five each other at the end of the day and say, “We did that ourselves.”

 

Last week I visited an ecovillage in British Columbia.  As described on the website, an ecovillage is a settlement in which “human activities are harmlessly integrated into the natural world in a way that is supportive of healthy human development and can be successfully continued into the indefinite future.”  This particular ecovillage, created in 1999, is called OUR (One United Resource) Ecovillage, and seems to have been started as a commune devoted to sustainable lifestyles.  At first 10 to 20 semi-permanent members were growing their own food and building small artistic houses out of cob, a mixture of clay, straw, and sand.  They planned to be a demonstration center where others could learn techniques of living close to the land, but nobody anticipated how wildly popular the concept would be.  The number of visitors and temporary residents exploded, reaching 10,000 a year.  People were coming from all over the world to see what was going on, revealing a tremendous hunger for getting back to nature.

 

 

Arriving at the gate of the 25 acre farm on Vancouver Island, my family and I were announced by a noisy flock of turkeys.  Patrick Jackson came out to greet us.  With a lovely South African accent and wavy blonde hair tied into a ponytail, Patrick looks like the aerial performer he used to be.  Patrick and his family have lived at the ecovillage since 2008, so he is an old-timer.  His job is to keep the legion of transient and unskilled volunteers working productively on the many building and agricultural projects that are in various stages of completion.

 

Patrick leads us to the outdoor dining area where a vegetarian lunch is just being served.  We have a bowl of onion soup with homemade croutons and vegetable slaw.  Patrick calls the kitchen a “zero mile eatery” because generally the meals consist of food grown on site.  They rarely serve meat, but they recently killed some chickens and are planning to butcher a pig in the fall.  A resident cow provides milk.

 

Brandy Gallagher, the executive director of OUR Ecovillage, sits down to visit while we eat lunch.  A social worker by training, she was raised in a commune in the wilderness.  Brandy describes herself as a “long, long term visionary.”  She explains that most communities like this one maintain a very low profile, staying as far away as possible from regulators and code enforcers.  Brandy has taken a different tack and tries to bring code enforcers around to her point of view; to compromise on acceptable ways to water the orchard with gray water and compost the latrine output.  I sense that sometimes the code people balk.  Brandy admits that she and the bank have different views of mortgage payments and community ownership, so the commune part of OUR Ecovillage is struggling a bit.  The education mission, in contrast, is proceeding full throttle.

 

Brandy rushes off and leaves me with a group of women who have just finished a two week permaculture design course.  They have been staying in tents and using a latrine.  The latrine is called the “Credit Union” because it takes deposits.  Withdrawals are also required; users have to take turns dumping the latrine bucket into the humanure composter.  One of the students, Rebecca, an ecology professor at Metropolitan State University in Denver, volunteers to give a tour.  We see the doomed pig enjoying a sunny day in a mud puddle.  Chickens and goats comingle around a coop near a greenhouse filled with produce.  Rebecca shows us a peach tree planted on the south side of a cob wall where it can soak up solar heat as the days get cooler.  She also shows us several of the latrines, which have apparently made quite an impression on her.

 

Most of the buildings, while quite artistic, are not completely finished.  I ask Rebecca how she, as a university scientist, interprets the non-linear thinking prevalent in the ecovillage.  She smiles and reminds me that solving humanity’s current problems will require all kinds of different thinking.
 
Rebecca and the peach tree soaking up solar warmth

My son Jeffrey in front of the "Credit Union"

A pig who doesn't know what's in store for her

A volunteer digging potatoes