Smoke from Wildfires

AIRNOW is a cross-agency U.S. government website devoted to air quality and its impact upon human health. The fire season has begun with a vengeance in California, with approximately 1100 fires burning today. Because of the tremendous number of wildfires burning in California, an unprecedented portion of the state is suffering hazy, smoke-laden air. Utilizing information from AIRNOW and other sources, including the American Lung Association and Environmental Protection Agency, here is a brief overview of important considerations related to what will undoubtedly be a very active fire season.

First and foremost, smoke from fires can affect your health. A person does not acclimate to smoke in any way, and repeated exposures can diminish lung function. So, avoidance is very important.

The discussion of intense exposure to heat and smoke when in the immediate proximity of a raging forest fire is a separate topic, because there are considerations of becoming burned, asphyxiated from lack of oxygen, affected by carbon monoxide, and injured by other severe, acute causations. The focus of what follows is exposure to smoke exposure of a degree to create a hazy horizon, where you can see, smell, and taste the smoke, and must make a decision to what extent, if any, you should modify your behavior and activities.

Healthy persons are usually not at a major risk from such smoke. But of course, it's always a good idea to avoid breathing smoke if you can help it. Smoke is not good for you.

Smoke is a mixture of gases and fine particles produced when wood and other organic matter burn. It reflects the fuel, so can contain products of combustion from rubber, plastics, and any other material consumed in the blaze. Firefighters have the greatest exposures to smoke, and they are often affected. It has been estimated that nearly 40 to 50% of medical encounters by wildland firefighters are for respiratory problems. Whether or not this statistic can be perfectly extrapolated to a non-firefighter population passively exposed to wildfire-generated smoke is not known, but it is highly likely that respiratory ailments and diminished lung function would be a logical result of exposure to smoke.

What's in the smoke. Some of the combustion products of concern include these classes of materials: particulate matter (organic and inorganic), carbon monoxide, ozone, organic acids, polynuclear aromatic hydrocarbons, volatile and semi-volatile organic compounds, and free radicals. These are present or absent in varying degrees depending on the fuel burned, temperature of the fire, suppression method(s) used, and other factors. Therefore, the toxicity of the smoke may vary, but for the purposes of this discussion, all smoke from wildland fires should be considered comparable.

Because particulate matter dominates in proportion within wildland fire smoke, the greatest health threat from smoke comes from the fine particles, which are often microscopic. The particles easily get into the eyes and respiratory system, where they can cause health problems such as burning eyes (conjunctivitis), irritated throat, runny nose (sometimes associated with an allergic response), and illnesses such as bronchitis (cough). Fine particles also can worsen chronic heart and lung diseases. Because death rates from these conditions have been noted to rise in a smoky environment, the smoke has been linked to premature deaths in people with these conditions, in a fashion analogous to increased mortality during heat waves.

Persons who are more susceptible to ill effects at lower smoke levels are those heart disease (congestive heart failure, symptomatic angina, cardiomyopathy), lung disease (asthma, reactive airway disease, chronic obstructive pulmonary disease [COPD]), and any medical condition in which oxygen delivery and heart and lung function are essential for health and wellness.

Older adults appear to be at increased risk of being affected by smoke, as do children with high activity levels. Firefighters, athletes, soldiers, and others who exercise in smoky conditions often report feeling poorly, sometimes up to the point of incapacitation.

It is not difficult to know if smoke is affecting you, if you develop symptoms. It is less easy to know if you are being affected if the impact is subtle. Obvious symptoms are irritated and reddened eyes; painful throat; fatigue; decreased exercise tolerance; palpitations; chest pain; shortness of breath or inability to draw a deep breath; coughing; wheezing; sinus irriation; headache; or worsening of pre-existing conditions that manifest any of these symptoms.

Prevention is key. One must know how to limit exposure to smoke:

Pay attention to local air quality reports, and to the Environmental Protection Agency's Air Quality Index (AQI)(more about this below). Stay alert for any news coverage or health warnings related to smoke. You can check out news on current status of wildfires by going to the website http://www.nifc.gov/

Use visibility guides, if they're available. Not every community has a monitor that measures particle levels in the air. In the western United States, some areas without air quality monitors have developed guidelines to help people estimate the AQI based on how far they can see.

Common sense is the cornerstone of everything we do in wilderness medicine. If it's smoky outside, do not plan to exert yourself. Do not run the race and consider keeping your children indoors. If you develop smoke-related symptoms, curtail any contributing activities and seek an environment away from the smoke. Ordinary dust masks are designed to filter out large particles, so do not count on them to diminish exposure to small particulate matter found in smoke.

The air indoors is also important during times of high smoke levels outdoors. So, you should keep indoor air as clean as possible. Unless it is extremely hot outside and you need to open windows and doors for air circulation, you should keep them closed. If you have an air conditioner, allow it to run, with the fresh air intake closed and the filter clean. Certain air cleaners might decrease particulate matter indoors, but be certain that the device does not emit ozone. Do not vacuum or smoke tobacco products, and do not burn anything that will emit smoke. If it becomes too hot inside a building or enclosure, find a cooler shelter, so that you are not overcome by the heat. When driving a car in smoky areas, keep the windows and vents closed.

AIR QUALITY INDEX (AQI) FOR PARTICLES

The AQI (see the color chart above) is an index for reporting daily air quality that indicates how clean or polluted is the air, and what associated health effects might be of concern. The EPA calculates the AQI for five major air pollutants regulated by the Clean Air Act: ground-level ozone, particle pollution (also known as particulate matter), carbon monoxide, sulfur dioxide, and nitrogen dioxide. Ground-level ozone and airborne particles are the two pollutants that pose the greatest threat to human health in the U.S. In the setting of smoke from a wildland fire, it is the particulate matter that is of greatest concern.

The AQI is reported as a numerical rating that runs from 0 to 500. The higher the AQI value, the greater the level of air pollution and the greater the health concern. For example, an AQI value of 50 represents good air quality with little potential to affect public health, while an AQI value over 300 represents hazardous air quality. When AQI values are above 100, air quality is considered to be unhealthy, at first for sensitive (to the harmful components) groups of people, then for everyone as AQI values get higher.

The AQI categories are:

0 to 50 Green Good
51 to 100 Yellow Moderate
101 to 150 Orange Unhealthy for Sensitive Groups
151 to 200 Red Unhealthy
201 to 300 Purple Very Unhealthy
301 to 500 Maroon Hazardous

Each category corresponds to a different level of health concern. The six levels of health concern are:

"Good" - The AQI value is between 0 and 50. Air quality is considered satisfactory, and air pollution poses little or no risk.

"Moderate" - The AQI value is between 51 and 100. Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a small number of people.

"Unhealthy for Sensitive Groups" - The AQI value is between 101 and 150. Members of sensitive groups may experience health effects. The general public is not likely to be affected when the AQI is in this range.

"Unhealthy" - The AQI value is between 151 and 200. Everyone may begin to experience health effects. Members of sensitive groups may experience more serious health effects.

"Very Unhealthy" - The AQI value is between 201 and 300. This triggers a health alert, because everyone may experience more serious health effects.

"Hazardous" - The AQI value is over 300. This triggers health warnings of an emergency nature. The entire population is more likely to be affected.

People living in close proximity to the fire-stricken areas should remain indoors and avoid inhalation of smoke, ashes, and particulate matter in the area. Ordinary dust masks, designed to filter out large particles, will not help as they still allow the more dangerous smaller particles to pass through. HEPA filter masks can remove nearly all airborne particles 0.3 micrometers (microns) in diameter, but they are more expensive and may be difficult to use for people with lung disease, because it can be hard to draw air through them.

If outdoor trips in smoky areas are necessary, breathing through a damp cloth may help filter out some of the particles that are floating in the air, but this is a temporizing measure only and should not be counted upon to significantly diminish smoke exposure for more than a few minutes.

Preview the 25th Anniversary & Annual Meeting of the Wilderness Medical Society, which will be held in Snowmass, Colorado July 25-30, 2008.

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The DAN Guide to Dive Medical Frequently Asked Questions (FAQ)

The DAN Guide to Dive Medical Frequently Asked Questions (FAQs) is a book to which I and other dive medicine authorities have contributed. This compilation of questions and answers by the Divers Alert Network (DAN) is available through DAN or from Best Publishing Company.

Here is the table of contents:

SECTION 1 - GENERAL
• Mask squeeze
• The scuba blues: DAN examines the possibilities behind flu-like symptoms following a dive
• Hand and foot edema after a dive
• To mix or not to mix: Is there a conflict with pseudoephedrine and enriched air diving?
• A tangled question: Is there a connection between aluminum scuba tanks and Alzheimer’s
• Post-dive symptoms
• Identifying the problem: DAN offers assistance in helping the non-diving companion to determine when or if the partner needs to call DAN
• Basic instincts: DAN explores a hypothetical underwater emergency using a medical perspective
• The training perspective: Dealing with the injured or panicked diver at depth

SECTION 2 – CARDIOVASCULAR
• Cardiovascular fitness and diving
• Pacemakers and diving
• Vasovagal and carotid sinus syncopes

SECTION 3 – DECOMPRESSION SICKNESS
• Return to diving: DAN takes a look at getting back in the water after experiencing decompression illness
• Diving after flying
• The industry examines flying after diving
• Low living, high diving: DAN discusses living at a subsea level and diving above sea level

SECTION 4 – DENTAL
• Dental work and diving
• Realignment: DAN talks about diving with dental braces
• Root canal
• Toothy wisdom: DAN sinks its teeth into dental issues & diving

SECTION 5 – EAR, NOSE AND THROAT
• Before the pressure gets too great, equalize
• The trauma of barotrauma
• Unplugged: DAN examines the use of earplugs

SECTION 6 – FITNESS TO DIVE
• Exercise training and scuba diving
• Fitness issues for divers with musculoskeletal problems
• Healthy, but overweight

SECTION 7 – GASTROINTESTINAL
• Gastrointestinal issues

SECTION 8 – HEMATOLOGY (BLOOD)
• Risk of diving with hemophilia

SECTION 9 – MARINE LIFE
• I’ve been stung: What should I do?
• Taking the sting out of jellyfish envenomations
• No fish tale: If you eat fish, it’s good to know about ciguatera – before you get sick

SECTION 10 – MUSCULOSKELETAL
• Diving & the body systems
• Lupus
• Diving after bone fractures

SECTION 11 – NERVOUS SYSTEM
• CNS considerations in scuba diving

SECTION 12 – OPHTHALMOLOGY (EYES)
• High pressure ophthalmology
• Eye surgery for divers
• The eyes have it: Mask defoggers

SECTION 13 – PSYCHOLOGICAL
• Psychological issues in diving – Part I: Depression, manic depression, and drugs
• Psychological issues in diving – Part II: How anxieties and phobias can affect diving
• Psychological issues in diving – Part III: Schizophrenia, marijuana and alcohol use

SECTION 14 – RESPIRATORY (BREATHING)
• Pulmonary considerations in diving
• Breathing easy
• Tight squeeze: Discomfort in a diver’s lungs and windpipe can come from a number of irritating sources

SECTION 15 – WOMEN’S ISSUES
• DAN explores fitness and diving issues for women

SECTION 16 – DECOMPRESSION ILLNESS AND SYMPTOM RECOGNITION

INDEX

The book carries a 2003 copyright, so there are a number of topics, including mine - entitled “I’ve Been Stung: What Should I Do?” – that would benefit from updates. Divers will be the beneficiaries of many new drugs and medical devices, so it is important that information about these as they relate to diving be kept current. As we learn more about the long-term effects of surgeries and medical conditions, opinions may be modified. However, despite the advances in medicine in general and in dive medicine in particular that have occurred since 2003 and that will continue to occur, there is a wealth of information in the book, so it should be useful to anyone who is a scuba diver or who intends to take up diving.

Preview the 25th Anniversary & Annual Meeting of the Wilderness Medical Society, which will be held in Snowmass, Colorado July 25-30, 2008.

Tags: DAN, Divers Alert Network, wilderness medicine, outdoor medicine, healthline

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Thank You to Shrink Rap for Grand Rounds

Thank you to Shrink Rap for including my second post in a series about medical professionals and the environment in this week's edition of Grand Rounds, which is entitled "Shrink Rap Grand Rounds: The iPhone 3G Edition." Grand Rounds is a weekly compilation of posts related to health care compiled by a host, who makes a great effort to compile an interesting collection for readers.

"Shrink Rap" is "a blog by psychiatrists for psychiatrists. A place to talk; no one has to listen. All patient vignettes are confabulated; the psychiatrists, however, are mostly real. Topics include psychotherapy, humor, depression, bipolar, anxiety, schizophrenia, medications, antidepressants, antipsychotics, ethics, psychopharmacology, forensic and correctional psychiatry, psychology, mental health, chocolate, and emotional support ducks. Don't ask."

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Outdoor Medicine and the Environment 2

In the first post on this topic, I put forward a framework of environmental issues that are among those on the forefront of discussion across science, industry, government, and the media. It is increasingly the case that environmental remediation recommendations are topics of great debate, for many reasons. Some reputable authorities do not agree with the proposed causation or acuity of environmental problems. Others astutely observe that some of the solutions proposed, such as diversion of crops for alternative fuels, may contribute to hunger and economic consequences that are more disruptive than expensive fuel, or even the consumption of fossil fuels.

Because the nature and magnitude of environmental changes have only recently come to be recognized, it is difficult to predict the attribution of inevitable to natural cycles, or whether the forces of nature are becoming unbalanced. Some suggest that while human activities have an effect on climate, there is not proof that this affects global temperature. For instance, there may be years during which global temperature declines. Others acknowledge the inevitability of global climate change, but recommend adaptation or geoengineering solutions.23 Opponents of those who predict irreversible global climate change and warming argue that until the precise nature and rate of these phenomena can be established, governments and industries should be tentative and cautious about making expensive policy decisions.24 Still, others point out that by focusing attention on global warming, there is a risk of not properly addressing more important environmental and health issues.

I am increasingly convinced that persons who argue against the magnitude and timing of global climate change are not doing so out of personal interests. They truly believe that our current surge in environmentalism is an over-reaction to a situation that may not be as dangerous as has been proposed. Wherein lies the burden of proof? Is it upon the conservationists, or those who demand data to support initiation of policies and practices with wide-reaching economic consequences? I think it is a shared responsibility. Beyond the data, we must certainly act with common sense.

Certain issues seem to me to be beyond calculated inaction. Developing alternative sources to substitute for fossil fuel consumption is widely supported. How can preservation of fossil fuels be bad, unless in the preservation, man unleashes some greater hardship upon the planet or its inhabitants? We are probably not yet at the stage where we should accept starvation in Africa as a consequence of our attempts to promote ethanol production for automobile fuel, but if we do not find a solution to pumping oil into our tanks, will be be creating even greater misery downstream? Despite the fact that there is almost universal assent and agreement on many issues, politics, economics, and special interests delay progress.

I cannot speak for everyone, but I have an opinion about the response needed from the medical profession. If one believes that there are situations upon which we should soon act, significant behavioral changes will be needed to begin to reverse apparent deleterious trends. Achieving global environmental change requires public and private efforts, led by a massive educational effort that should include all institutions of higher learning, including schools of medicine. By virtue of their knowledge and experience, physicians are rightfully concerned about individual and population health. However, the germs and disease processes with which we have become familiar may not pose as great a threat as what might result from such environmental eventualities as the melting of the polar caps.

It is my feeling that the time has come to broaden what the medical profession (and in particular, those with an interest in wilderness medicine) must learn, expanding awareness by educating physicians about the best environmental science. Given the hypothetical and known links of global climate change to human health, and the increasing concern that this change is accelerating, it is our duty to become informed.

Accordingly, in response to the environmental imperatives, an educational action plan is appropriate for the medical profession. Nelson25 noted about environmental studies, “ . . . the subject matter is all-encompassing. It includes . . . the air, water, minerals, soil, forests, oceans, lakes and rivers, as well as all living things in the seas and on land, the relationship and influence of each on the others, plus economics, politics, religion, culture, and philosophy. And, although we will never know or understand more than a small fraction of the endless intricacies of nature’s works, we can comprehend and learn the general principles that should guide our conduct as a society, if we are to preserve a livable habitat. The proposition is, quite simply, that we must conduct our activities in such a way as to protect the integrity of our ecosystems and their resources. . . ”

REFERENCES
23. Foreign Policy Web site. Why climate change can’t be stopped. http://www.foreignpolicy.com/story/cms.php?story_id=3980. Accessed December 9, 2007.
24. Botkin DB. Global warming delusions. Wall Street Journal. October 17, 2007;A19.
25. Nelson G. A clean environment and a prosperous economy: can we have both? J Wilderness Med. 1991;2(1):1-6.

image courtesy of www.theeagle.com

Preview the 25th Anniversary & Annual Meeting of the Wilderness Medical Society, which will be held in Snowmass, Colorado July 25-30, 2008.

Tags: climate change, environment, global warming, ozone,wilderness medicine, outdoor medicine, healthline

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Wilderness Medicine at Weill-Cornell Medical College

This just came in from my good friend Dr. Jay Lemery, who practices emergency medicine in New York City, and who is a rising star in the field of wilderness medicine:

"Please forward to any interested students. Thank you!

Weill-Cornell Medical College Combined Elective in: Emergency Medicine & Wilderness and Environmental Medicine (MED 130: September 29- October 25, 2008

We are pleased to announce our semi-annual elective for the 2009 fall semester. This will be a combined 1-month elective in Emergency Medicine and Wilderness Medicine:

[Emergency Medicine: September 29 - October 12 at New York-Presbyterian Hospital/Weill Cornell Medical Center; October 13 - 25 Wilderness Medicine. Third & 4th year medical students are eligible.

Emergency Medicine: 2-week clinical elective at the Weill Cornell Campus of NY-Presbyterian Hospital

Wilderness Medicine: We offer a state of the art course loaded with hands-on medical training. This program has been previously taught and has had superlative reviews from students. Week 1 in New York City will consist of lectures, workshops, trips to the Bronx Botanical Garden (Botanical Medicinals) and the Bronx Zoo (Reptile House), and Principles of Disaster Response taught by our EMS Special Operations Team. Week 2 will take place in the backcountry of the Adirondacks, involving High Peak and Lake Champlain ecosystems.

Space will be limited, and we will accommodate on a first-come, first-served basis. Third and 4th year medical students are encouraged to enroll at: http://www.nypemergency.org/residency/

Please direct any questions to Dr. Jay Lemery, who is the course director, at lemery@med.cornell.edu.

The goal of the Department of Emergency Medicine's Wilderness Medicine & Environmental Preparedness Elective for medical students is to offer an introduction to backcountry care and to teach improvisational treatment skills to students. The knowledge and skill sets required for medical care in severe, adverse environments will be applicable for patients in the wilderness as well as in the settings of man-made or natural disasters. Our experienced faculty and guest instructors, working closely with the faculty from Cornell Outdoor Education (COE) at our Ithaca campus, will utilize all of the desired knowledge and proficiency in leading large groups into the backcountry. The curriculum combines lectures, hands-on scenarios and case-based learning. We anticipate that this course will be helpful to any senior medical student applying to any of a variety of clinical residency programs."

Preview the 25th Anniversary & Annual Meeting of the Wilderness Medical Society, which will be held in Snowmass, Colorado July 25-30, 2008.

Tags: Jay Lemery, Weill Cornell Medical College, wilderness medicine, outdoor medicine, healthline

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Thank You to Marianas Eye for Grand Rounds

Thank you to Marianas Eye for including my post about artesunate for falciparum malaria in this week's edition of Grand Rounds, which is entitled "Grand Rounds from the South Pacific." Grand Rounds is a weekly compilation of posts related to health care compiled by a host, who makes a great effort to compile an interesting collection for readers.

Marianas Eye is "a Saipan blog about life on a tropical island through the eyes of South Pacific eye surgeon, Dr. David Khorram. Here you will find island adventure, food, culture, humor, travel, medicine, and random thoughts about living a fulfilling life (along with an occasional gory eye picture thrown in, just to keep things fresh.) It is very entertaining, informative, and a reading pleasure.

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Get Outdoors - 2nd Anniversary of Medicine for the Outdoors

This post marks the 2nd anniversary of this Medicine for the Outdoors blog. With this post, we're at 319 posts and still going strong. It wouldn't be possible without you, the readers. If you can take a moment to let a few friends know about the blog and have them sign up as subscribers, we can keep up the momentum. Send along your comments and help stimulate the discussions. The more energetic your participation, the better. I'm certain that there is no shortage of expertise among the readership, so please share your knowledge and experiences with us.

I recently read a brief notation in Scientific American that “Americans are losing interest in going outdoors.” This comment was offered by a writer who based his opinion on “researchers” who “analyzed trends in visits to parks and forests and in licenses for activities such as hunting and fishing.” He noted that these visits appear to have been declining at roughly one percent per year since 1991, and then concluded that “electronic diversions may be taking over, and that increasing school and work pressure(s) and a fear he calls “stranger danger” may be contributing.

If this is true, then it is worrisome, but before we draw conclusions, I think we need to know how representative the statistics referenced are for the outdoor enthusiast population at large. Are visits to parks and forests, which may require expensive modes of transportation, indicative of how many individuals spend their time on local outdoor activities? Are hunters and fishermen representative for cyclists, rock climbers, skiers, scuba divers, scouts, mountaineers, and all of the other outdoor and adventure enthusiasts? I cannot be certain, but I doubt it. My observations, and those of many others, is actually quite the opposite – namely, that outdoor recreation is one of the fastest growing modes of recreation. People love to be outside, and in our desk-sitting modern society, it's a good thing.

So, let’s not throw out the baby with the bathwater. The average American probably eats too much, has too much body fat, and doesn’t get enough exercise. Children today certainly have more opportunities to become couch potatoes, and often consider a workout to be a session with Nintendo or Guitar Hero. I recall my youth, and how much time I tried to be outside, even in a relatively urban environment, and watch children today spend more time indoors, less time exploring, and far less time on adventure. I share the author’s concern that we may be approaching a time when exploration and adventure are more intimidating and of necessity occur within a more structured and restricted environment.

But if we observe all of this in its totality, being outdoors is not restricted to such activities as a hike in the woods or a float down a river. If your child kicks a soccer ball, throws a Frisbee, or swings a baseball bat, he or she is outside. If you play golf, walk the dog, or wash your car at the park, you are outside. It may be more difficult to find fresh air, but it is out there. We will all be more conservation minded if we set a goal to be outside without having to wear an N95 filter mask and gradually expand, not contract, our protected wilderness areas. If a decline in the statistics noted by the author in Scientific American represent anything about which we should be concerned, it is that in the diminution of exposure to the outdoors, we run the risk of losing interest. For the sake of future generations, we cannot afford to do that.

Inherent in outdoor activities are risks, as we well know from current environmental hazards such as the wildfires in northern California, and tornadoes and floods in our heartland. There will always be a need for sound medical practice and advice in the outdoors, which by definition sounds words of caution. But Medicine for the Outdoors exists because every wilderness is a magnificent place, and I will always be a proponent of seizing opportunities to run rivers, slide down dunes, hike trails, dive on reefs, and spend nights under the stars. Wilderness medicine is mostly about taking care of fundamentally healthy individuals who get into trouble doing the things they love, and so it is doubly gratifying.

photo by Brenda Tiernan

Preview the 25th Anniversary & Annual Meeting of the Wilderness Medical Society, which will be held in Snowmass, Colorado July 25-30, 2008.

Tags: Medicine for the Outdoors, wilderness medicine, outdoor medicine, healthline

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Artesunate for Falciparum Malaria

Malaria is an infectious disease that can be devastating. More than a million persons die each year out of hundreds of millions of cases of the disease. Malaria is caused by infection with one of four microscopic parasites: Plasmodium falciparum, P. vivax, P. malariae, or P. ovale. These are transmitted in the wild by the bite of an infected Anopheles mosquito. Most cases of malaria acquired by U.S. citizens are contracted in sub-Saharan Africa; most of the remainder are linked to travel in Southeast Asia, Central and South America, the Indian subcontinent, the Middle East, and Oceania.

When a female mosquito bites a human infected with malaria, it ingests an immature form of the parasite. In approximately two weeks, the parasite matures within the mosquito. When the infected mosquito bites a non-infected human, it releases malaria sporozoites (an immature form of the parasite), which mature in the human liver to become merozoites, and which then invade red blood cells. From these locations, the organisms can penetrate the vital organs, such as the brain, lungs, liver, and kidneys. Within a few days, the infected red blood cells burst and the parasites infect more red blood cells. The incubation period between acquisition of the parasites and the onset of symptoms is 8 to 40 days, depending on the species. Up to a third of victims may not show the disease until after 60 days from the time of the initial mosquito bite. Typical symptoms include a flu-like illness, with headache, chills, sweats, fatigue, loss of appetite, muscle aches, nausea, and vomiting. These are soon followed by episodes of headache, intense chills, high fever, and sweating. Jaundice and anemia may occur. The episodes last 1 to 8 hours and are separated by 2 to 3 days.

The most serious illnesses and deaths are attributed to Plasmodium falciparum.Persons infected with falciparum malaria may become dreadfully ill, with episodes of fever and chills at closer intervals than suffered with the other forms of malaria, and lasting sometimes for more than 30 hours. Severe malaria can be fatal or lead to anemia, heart and kidney failure, and/or coma; untreated infections can cause recurrent illness for years. Identification of the specific plasmodium is accomplished by observing the parasites under the microscope in blood smears.

In an article entitled "Artesunate for the treatment of severe falciparum malaria" (New England Journal of Medicine 358:1829-36), Dr. Philip J. Rosenthal notes that the most important new class of antimalarial drugs is the artemisinins, which are natural products that were first developed in China in the 1960s. Artemether (an artemisinin, or quinghaosu, derivative) has been shown to be as effective as quinine in the treatment of severe P. falciparum malaria. Other artemesinin derivatives include artesunate, artemotil, and dihydroartemisinin. One key advantage of these agents is that they are active against all of the red blood cell stages of the parasite. Also, so far there is limited if any resistance to these agents. Because all artemisinins are very effective in killing the parasites, they are rapidly cleared from the blood stream, so must be used in combination with longer acting drugs. Artemisinin-based drugs are used in combination with other drugs, such as mefloquine, lumefantrine, amodiaquine, or piperaquine as first-line therapies for uncomplicated malaria in countries other than the U.S. In the United States, intravenous artemesinin is still considered an investigational drug, so must be obtained from the Centers for Disease Control (CDC). It is used for 3 days, then followed by a longer-acting oral drug such as doxycycline, clindamycin, atovaquone-proguanil, or mefloquine.

Unfortunately, there is not yet a useful vaccine against malaria. Avoidance of mosquito bites is key to prevention. Because the Anopheles mosquito tends to feed during the evening and nighttime, it is particularly important to sleep under nets or screens; spray living quarters (with, for instance, a pyrethrin-containing product) and clothing (with, for example, permethrin 0.5%, Duranon, or Permanone; or concentrated Perma-Kill 4 Week Tick Killer, diluted and applied to clothing); and wear adequate clothing and insect repellent (N,N-diethyl-3-methylbenzamide, called DEET) at these times.

In an article entitled "Fake Artesunate In Southeast Asia" by Paul Newton, Stephane Proux, Michael Green, Frank Smithuis, Jan Rozendaal, Sompol Prakongpan, Kesinee Chotivanich, Mayfong Mayxay, Sornchai Looareesuwan, Jeremy Farrar, Francois Nosten, and Nicholas J White, the Global Pharma Health Fund instructs that artesunate is a key antimalarial drug in the treatment of multidrug-resistant Plasmodium falciparum malaria in southeast Asia. The authors investigated the distribution of counterfeit artesunate tablets using a special dye technique. Of 104 shop-bought "artesunate" samples from Cambodia, Laos, Myanmar (Burma), Thailand, and Vietnam, 38% did not contain artesunate. This illicit and murderous trade in counterfeit antimalarials is a great threat to the lives of patients with malaria.

To determine the malaria risk within a specific country and to learn of the most recent recommendations for prophylaxis and drug therapy, you can seek information from one of many sources on the Internet, such as http://www.cdc.gov/malaria/

Preview the 25th Anniversary & Annual Meeting of the Wilderness Medical Society, which will be held in Snowmass, Colorado July 25-30, 2008.

Tags: malaria, artesunate, wilderness medicine, outdoor medicine, healthline

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Thank You to NHS Blog Doctor for Grand Rounds

Thank you to NHS Blog Doctor for including my post about outdoor medicine and the environment in this week's edition of Grand Rounds. Grand Rounds is a weekly compilation of posts related to health care compiled by a host, who makes a great effort to compile an interesting collection for readers.

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Typhoid Fever Vaccine

Typhoid fever is caused by the bacteria Salmonella typhi, which are transmitted among humans through ingestion of contaminated food or water. Most cases are acquired abroad under conditions of poor hygiene.

After an incubation period of 10 to 14 days, victims suffer fever with or without diarrhea and abdominal pain. Most victims also complain of headache, fatigue, and loss of appetite. “Rose spots,” which are 2 to 4 mm red spots on the trunk that blanch (lose their color) when pressed, are seen in some cases. The liver may become inflamed.

Most cases resolve in 3 to 4 weeks. The seriously stricken individual may suffer a severely inflamed bowel, bleeding from the gastrointestinal tract, pneumonia, heart failure, severe fever, and death.

A physician who diagnoses typhoid fever will treat the victim with an intravenous antibiotic. The layperson can use trimethoprim-sulfamethoxazole; administer one double-strength tablet twice a day for 2 to 3 weeks. You can also use ampicillin 100 mg per kg (2.2 lb) of body weight in four divided doses for 2 to 3 weeks. It is important to keep the victim from becoming dehydrated.

Injectable and oral vaccines to prevent typhoid fever are available to people traveling to areas of high risk. Typhim Vi polysaccharide vaccine is available for immunization against typhoid fever caused by Salmonella typhi. Immunization is recommended only for travelers who visit regions (e.g., Nepal, South Africa, Indonesia) known to harbor the disease. A single intramuscular injection is required, followed by booster injection at 2-year intervals, depending on the local disease risk. An oral vaccine (Vivotif Typhoid Vaccine Live Oral Ty21a [Berna]) is given as one capsule every other day for four doses in people age 6 years or older. A booster series is necessary every 5 years. Side effects, which include fever, headache, and flu-like symptoms, are more commonly associated with the injections than with the oral capsules.

According to Berna Products, here are some recommendations on how to take typhoid vaccine capsules:

DO's:

1. DO complete taking the capsules at least one week before traveling.
2. DO take each capsule on an empty stomach (1 hour before eating or 2 hours after eating).
3. DO take each capsule with a full glass of cool or lukewarm water.
4. DO keep capsules in the refrigerator.

DON'T's:

1. DON'T take the vaccine if you are taking antibiotics (consult your doctor).
2. DON'T take the vaccine with alcohol (wait at least 2 hours before drinking alcohol).
3. DON'T open or chew the capsules.
4. DON'T forget to skip a day between capsules.
5. DON'T forget to take all 4 capsules.

The capsules are designed to stay intact and only dissolve then they reach the small intestine. The capsules should be taken at approximately the same time each day. If a person has had an adverse reaction to the oral typhoid vaccine or any other enteric coated capsule in the past, the oral vaccine should not be taken. If the person has a fever, continued vomiting, or diarrhea/stomach illness, the oral vaccine should not be taken.

It is very important to remember that this vaccine is not foolproof, so even if a person is vaccinated, he or she should avoid potentially contaminated food and water.

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Outdoor Medicine and the Environment

I was recently fortunate to have a commentary entitled "Physicians and the Environment" published in the Journal of the American Medical Association. It was an invited piece, and reflected some of my thoughts about current environmental issues and the role of the medical profession in achieving the education necessary to be able to intelligently respond to these issues. I am going to use parts of that commentary to put this into context for the layperson, and am therefore including the references where appropriate from the original commentary.

As I have mentioned previously, there is every reason for persons involved and interested in wilderness and outdoor medicine to be advocates for preservation of the environment. The entire concept of "wilderness medicine" is predicated upon the existence and improvement of wilderness areas, which are among the most pressured and rapidly receding parts of planet Earth.

In many circumstances in the past, the medical profession has responded to adverse situations of global reach, such as epidemic diseases, genocide, the threat of nuclear war and natural disasters. As the world’s scientists, governments, and businesses now confront the state of the environment, all manner of health care professionals also must be prepared to respond, because in the final analysis, health matters are integral to the predicament, predictions and discussion. Beyond being just a reliable resource, given the magnitude and complexity of issues as they relate to human health, the medical profession should accept the challenge of becoming a leader in the discussions and debates.

Despite our preoccupation with armed conflicts and the economy, the environment is perhaps today’s most pressing global issue, as it contributes not only to direct effects, but to other situations of concern, such as economic decline and civil disobedience. Environmental conditions contribute to the presence or intensity of many medical conditions, such as temperature-related morbidity and mortality, health effects of extreme weather events (e.g., storms, floods, tornadoes, hurricanes, and precipitation extremes) and their sequelae (e.g., oceanic algae blooms), ecological change (e.g., the potency of certain harmful plants, such as poison oak), starvation, allergies, pollution-related health effects, water- and food-borne diseases, and vector- and rodent-borne diseases.1,2

As we learn more, it becomes apparent that the full eventual effects of global climate change and other environmental issues are not necessarily easily defined or well predicted. There are multiple views surrounding every issue. Some of the most important issues that need to be continuously examined from every angle include global warming, depletion of stratospheric ozone and increases in ground-level ozone, destruction of forests, polar melting, deficiencies in water production and sanitation, and human population growth and dynamics.

There are and will be significant differences of opinions about what follows here. My comments are properly interpreted as being "pro-environment" or "green," leaning toward the perspective that advocates that there are significant environmental problems and that many of these can be attributed to the activities of humans. However, I most certainly acknowledge the rights and responsibilities of others to hold different viewpoints and opinions, and the value of their being skeptical about science and conclusions. The most important thing is that we do not become acrimonious or disengaged, because it will take all of our skills of observation, analysis, and collaboration to reach consensus on these matters in a timely fashion and in a way that promotes improvement, not conflict. The acts of remediation are expensive and potentially diverting (from other problems), so no significant change should be taken lightly.

Global Warming. Atmospheric accumulation of gases (predominately carbon dioxide, methane, nitrous oxide, and halocarbons) traps heat by the greenhouse effect.3 The Intergovernmental Panel on Climate Change predicted that average global temperature will continue to increase, and a major concern is the rate of warming.4 Compared with the century 1906-2005 required to raise the earth’s average atmospheric temperature by 0.56 degrees Centigrade, some suggest that only a decade may be needed to raise it another 0.28 degrees C.5 This rate of change has been created by burning fossil fuels in power plants and for transportation, a decline in carbon intensity reductions, and natural sinks removing a smaller proportion of emissions from the air.6 Each year, more than 1.2 cubic miles of oil, 3.5 billion metric tons of coal, and 100 trillion cubic feet of natural gas are burned worldwide, releasing 30 billion tons of carbon dioxide into the atmosphere.7 Without efforts to stabilize or decrease consumption of fossil fuels, the 14.9 billion metric tons of carbon emissions released by the United States, the European Union, China, and India in 2005 are projected to increase to 25.6 billion metric tons in 2030.8 Even if one disputes the precise numbers, we seem to be on an unsustainable spree of consumption. Is global warming due to rising carbon dioxide levels, and are these rising levels attributable to the activities of humans, or are these environmental "facts" part of a series of coincidences? We need to know the answer. How many barrels of oil, tons of coal, and cubic feet of natural gas can be extracted from the earth before we run out? At our current rates of consumption, when will this occur? We need to know the answers.

Depletion of Stratospheric Ozone. Chlorofluorocarbons and other ozone-depleting substances released into the atmosphere are major contributors to the destruction of ozone in the stratosphere. Depletion of the ozone layer exposes the earth’s inhabitants to increased amounts of harmful ultraviolet-B radiation. This contributes to skin cancer, cataract formation, suppression of the immune system, and damage to certain crops.9 This is counter-posed by accumulation of ozone at ground level, which contributes to lung disease and other health risks.

Destruction of Forests. Fires set to clear forests for agriculture and grazing release carbon dioxide, which is a contributing factor to global warming. According to the World Bank, approximately 22 million acres of rain forests are destroyed by intentional fires each year, accounting for approximately 20% of worldwide carbon dioxide emissions.10 Wildfires, often coinciding with droughts, generate additional atmospheric carbon dioxide.11 In preindustrial times, the atmospheric abundance of carbon dioxide was relatively constant at 280 ppm; in the 1950s, the level was 300 ppm; in 2006, it had attained 381 ppm; and in 2008 it is increasing.12 At what rate are these forests being re-planted? Can men and women continue to remove habitat, plants, animals, and minerals from planet Earth at current rates and be assured that this does not pose a catastrophic future for our populations of life forms? We need to know the answers.

Polar Melting. Consistent with the increase of global temperature, there is a loss of snow cover in the Northern Hemisphere, the amount of Arctic and Antarctic sea ice is diminishing, and glaciers are melting.13 Predictions suggest that in the next few centuries, sea levels could rise by as much as 17.8 cm to 6 m, and the Gulf Stream may be diminished or even eliminated.14 In low-lying coastal areas where populations cannot be protected by natural or artificial barriers, large numbers of climate refugees may be forced to migrate to other locations, thereby increasing population crowding. Global climate change also is predicted to contribute to flooding and fire risk; increase the intensity of cyclones (hurricanes) and heat waves; accelerate beach erosion and desertification; hasten species extinction; and diminish water and food (livestock, fish, and plants) availability.15 I have heard many arguments about animals, such as polar bears, that putatively face extinction because of hunting, habitat and climate change, loss of food supply, etc. Are important animal populations declining? Can or should we intervene in the decline of any species? What does history tell us about the effects of rising and falling sea level? We need to know the answers to these questions.

Deficiencies in Water Production and Sanitation. Sachs16 contends that global climate change will tighten the availability of water, and force migration of hundreds of millions of individuals over the course of a few decades. According to the United Nations, more than 5 billion persons on Earth may live under severe water stress by the year 2025.17 Currently, 1.1 billion persons lack adequate water worldwide, 2.6 billion lack adequate sanitation, and 1.8 million children die each year because of one or both of these deficiencies.18 The outdoors can be beautiful, marvelous, and a tonic for the body and spirit, but it can also be a cruel, terrifying environment of forced survival. What is the true status of our water supplies, nation by nation, region by region? We need to know.

Human Population Growth and Dynamics. The human population is increasing exponentially, which has an unprecedented global effect on ecology and biodiversity. This effect takes place through overharvesting, introduction of nonnative species, pollution, and habitat fragmentation and destruction.19 As large, developing countries face increasing energy demands, they will undoubtedly burn increasing amounts of fossil fuels. The environmental conditions and climate changes that have been touted as major influences on health may potentially involve millions of individuals being injured or killed by floods, tsunamis, and cyclones; tens of millions afflicted by poorly controlled diseases that might emerge as a consequence of unchecked vectors (such as mosquitoes); hundreds of millions malnourished due to desertification, loss of crops, and insufficient potable drinking water; and ultimately, poor health and the loss of prosperity as individuals are crowded into a reduced landmass that may be too small to reasonably support their survival.20,21 The worldwide growth of the human population dramatically increases the possibility of loss of life-sustaining resource bases during large geological and weather events in a manner that limits human survival. Simply put, the more pins standing behind the lead pin when the bowling ball strikes, the more that are vulnerable to being struck down and swept away. We need to be very thoughtful about this, because hunger and economic deprivation inevitably lead to conflict and even war. So, basic human needs may trump our desire to divert crops, such as corn, to alternative fuels. We are already witnessing these effects.

While there are a wide variety of opinions about the timeline for such events, the arguments supporting environmental trends are substantiated by reasonable scientific observations.2,22 Proponents of accelerating global climate change suggest that given the rapidity of changes and their unforeseen consequences, successful adaptation would appear unlikely and unattainable. The most viable solution is to halt the inexorable assault on the environment as quickly and effectively as possible. Arguments that do not support these trends are espoused by dispassionate and intelligent individuals, who also care very much about their planet, but do not necessarily agree with the scientific conclusions indicating human-generated planetary degradation and climate change. Which faction is correct? Issue by issue, point by point, we need to know. What might be at stake are the futures of species and resources that cannot be easily regenerated, if they can be regenerated at all. On the other hand, if there are better approaches than those currently favored by environmentalists, then let them be identified and implemented.

image courtesy of National Museum of Australia Canberra

REFERENCES
1. Patz JA, McGeehin MA, Bernard SM, et al. The potential health impacts of climate variability and change for the United States: executive summary of the report of the health sector of the US national assessment. Environ Health Perspect. 2000;108(4):367-376.
2. Confalonieri U, Menne B, Akhtar KL, et al. Human health. In: Parry ML, Canziani OF, Palutikof JP, van der Linden PJ, Hanson CE, eds. Climate Change 2007: Impacts, Adaptation, and Vulnerability: Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, England: Cambridge University Press; 2007:391-431.
3. Collins W, Colman R, Haywood J, Manning MR, Mote P. The physical science behind climate change. Sci Am. 2007;297(2):64-73.
4. Parry ML, Canziani OF, Palutikof JP, van der Linden PJ, Hanson CE, eds. Climate Change 2007: Impacts, Adaptation and Vulnerability: Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel of Climate Change. Cambridge, England: Cambridge University Press; 2007.
5. Solomon SD, Qin M, Manning Z, et al. Climate Change 2007: The Physical Science Basis: Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, England: Cambridge University Press; 2007.
6. Canadell JG, Le Que´ re´ C, Raupach MR, et al. Contributions to accelerating atmospheric CO2 growth from economic activity, carbon intensity, and efficiency of natural sinks. Proc Natl Acad Sci U S A. 2007;104(47):18866-18870.
7. Project Genie. Web site. http://www.projectgenie.org.uk. Accessed December 1, 2007.
8. International Energy Agency. Web site. http://www.iea.org. Accessed November 29, 2007.
9. Longstreth J, de Gruijl FR, Kripke ML, et al. Health risks. In: Environmental Effects of Ozone Depletion: 1998 Assessment. Nairobi, Kenya: United Nations Environment Programme; 1998.
10. World Bank Group. Pilot program to conserve the Brazilian rain forest. http: //www.worldbank.org/rfpp/overview/overview_what.htm. Accessed December 9, 2007.
11. Wiedinmyer C, Neff JC. Estimates of CO2 from fires in the United States: implications for carbon management. Carbon Balance Manage. 2007;2:10.
12. National Oceanic and Atmospheric Administration, Earth System Research Laboratory, Global Monitoring Division. Trends in atmospheric carbon dioxide. http: //www.esrl.noaa.gov/gmd/ccgg/trends/. Accessed January 15, 2008.
13. Nicklen P. Vanishing sea ice. Natl Geogr Mag. 2007;211(6):32-55.
14. BBC Weather Centre. Climate change. http://www.bbc.co.uk/climate/impact /gulf_stream.shtml. Accessed December 10, 2007.
15. Trenberth KE. Warmer oceans, stronger hurricanes. Sci Am. 2007;297(5):45-51.
16. Sachs JD. Climate change refugees. http://www.sciam.com/article.cfm? chanID=sa006&articleID=E82F5561-E7F2-99DF-36D3CB7EB5DA209C&ref=rss. Accessed January 12, 2008.
17. United Nations Water for Life. Fact sheet on water and sanitation. http://www .un.org/waterforlifedecade/factsheet.html. Accessed December 8, 2007.
18. World Water Council. Water crisis. http://www.worldwatercouncil.org/index.php?id=25. Accessed January 20, 2008.
19. Biodiversity & Human Health Web site. The effect of human population on biodiversity. http://www.ecology.org/biod/habitat/human_pop1.html. Accessed December 9, 2007.
20. Kerr RA. Global warming is changing the world. Science. 2007;316(5822):188-190.
21. Campbell-Lendrum D, Corvalan C, Neira M. Global climate change: implications for international public health policy. Bull World Health Organ. 2007;85(3):235-237.
22. Meehl GA, Washington WM, Collins WD, et al. How much more global warming and sea level rise? Science. 2005;307(5716):1769-1771.

Preview the 25th Anniversary & Annual Meeting of the Wilderness Medical Society, which will be held in Snowmass, Colorado July 25-30, 2008.

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Thank You to The Happy Hospitalist for Grand Rounds

Thank you to The Happy Hospitalist for including my post about automated external defibrillators (AEDs) in this week's edition of Grand Rounds. Grand Rounds is a weekly compilation of posts related to health care compiled by a host, who makes a great effort to compile an interesting collection for readers.

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