CLIMATE AND HEALTH IN NEW ZEALAND- Medical Audiences
CLIMATE AND HEALTH SCRIPT FOR NZ MEDICAL AUDIENCESNew Zealands climate is changing. We have warmer winters and hotter summers. Wet areas are gettingwetter and dry areas drier, with more frequent drought, more heavy rains and more powerful storms.How do these changes affect our health?HEAT WAVE Extreme heat causes more deaths than any other type of extreme weather event. A heatwave in Europe in the summer of 2003 caused 70,000 deaths. Another in Russia in 2010 killed56,000 people.DISEASE SPECIFIC MORTALITY Old, young, people with chronic diseases, outdoor workers andthose taking beta blockers, diuretics, antipsychotics, antidepressants, and anticholinergics aremore susceptible to heat related illness and death. Pregnant women and their unborn babies are alsoaffected with increased rates of congenital anomalies and preterm birth. City dwellers are at higher riskdue to the urban heat island effect: with absorption and radiation of heat from dark asphalt andcement, it can be 9 deg hotter in cities than the surrounding suburbs. Human response to extreme heatalso depends on timing, location and duration. We adapt to higher temperatures over time, so extremeheat causes more harm when it occurs earlier in the summer. The mortality threshold depends onwhether the population is accustomed to a hot climate. Aussies, for example, are less susceptible thanKiwis. Heat effects are cumulative in the short term. The impact of a given temperature on day 6 is 2-5x greater than the same temperature on day 1. When you think about heat waves, you may imaginelittle old ladies keeling over alone in their apartments, but heat waves fill hospitals with increased EDvisits and admissions for heart, lung, and kidney disease. A heat wave in Australia in 2009 bumped uphospital admissions 14-fold and increased ED visits for ischemic heart disease in middle aged patientsby almost 40%. Heat waves dont just kill us, they make us kill each other. Extreme heat increasesaggression and results in increased rates of assault, murder, domestic violence, suicides and psychiatricholds for being a danger to others.TASMANIA FUTURE HEAT WAVES I could not find projections on extreme heat for NZ,Tasmania was the closest. There the number of hot summer days will double to triple by the end of thecentury. Heat waves will quadruple in frequency and, in the northern third of the island last anywherefrom a week to month longer than they do now.FOOD POISONING Increased ambient air temperature affects food safety even when not extreme.The most common cause of FP in NZ is campylobacter from inadequately cooked chicken. Rates havebeen rising steadily since the 80s. In 2011 a study in 3 meat processing facilities found camplyobacterin 99% of samples. Warm weather promotes rapid spread of the campylobacter in poultry flocks andincreases the multiplication of bacteria at every step between the farm and your fork. Every 1 degreeincrease in temperature raises the incidence of campylobacter and salmonella by 2-5%.VIBRIO AND SEA SURFACE TEMPERATURE Whats true for warm air is also true for warmwater, which increases the amount of Vibrio bacteria in shellfish. Despite monitoring and closingcommercial shellfish operations when bacteria counts are high, the US has had a dramatic increase inVibrio infections. There are two common pathogenic marine Vibrios, vulnificus and parahemolyticus.Vibrio parahemolyticus generally causes gastroenteritis and occasionally septicemia. Vulnificus causesgastroenteritis in 10% of cases and those are the lucky ones. 90% of the time it causes primarysepticemia which is 50% fatal. The very young, very old, and people with liver disease and impairedimmune function are more susceptible. In the US Vibrio causes 95% of seafood related deaths.The prevalence of Vibrio in NZ shellfish has increased since the 1980s. In the summer of 2009 V.parahemolyticus was found in 95% of sampled commercial shellfish although only a small percentagehad the genes for pathogenicity. Vibrio vulnificus was present in 17% of samples. There was a clear
relationship between Vibrio levels and water temperature.PARALYTIC SHELLFISH POISONING Warmer oceans also promote harmful algae blooms whichform heat stable neurotoxins that accumulate in fish and shellfish. Paralytic shellfish poisoning canrange from tingling of the lips and hot/cold reversal to flaccid paralysis and respiratory failure. Themortality rate ranges from 9-15%. There have been 29 hospitalizations for PSP in the Waikato districtsince mid December from shellfish obtained in the Bay of Plenty, where warnings are still in place. Awarning on the West Coast began in October and was only recently lifted. Ciguatera is another algaltoxin which concentrates up the food chain to large tropical reef fish, causing GI and neurologicsymptoms. Ciguatera does not affected fish caught in NZ waters but does affect Pacific Islanders in NZwho eat fish from their home countries. In one survey over half of NZ Pacific Islanders queriedreported eating seafood brought back by relatives in the past 12 months.BLUE GREEN ALGAE Warmer water temperature combined with nutrient rich runoff from heavyrain in agricultural areas causes cyanobacteria blooms in fresh water. These produce several toxins, themost common being microcystin. Microcystin causes hepatitis with acute ingestion and liver cancerwith prolonged low level exposure. It cannot be destroyed by boiling. Children and pets are mostvulnerable to acute exposures because of their small size and tendency to play at the waters edge wherethe algae is thickest. With a thick layer of algal scum at the shore, toxin concentration is increased 100fold. With a strong wind blowing lake scum in to the shoreline concentrations can increase 1000 fold.Fish and shellfish can concentrate microcystins. There is currently a public health warning for shellfishwith high microcystin levels in Hokianga Harbour due to an algae bloom in Lake Omapereupstream. Three other lakes in northern north island are currently closed to recreational use due to highlevels of microcystin.MOSQUITO BORNE INFECTIONS The US and Australia are experiencing rapid spread andemergence of mosquito borne arboviruses such as Dengue, West Nile and its Australian cousinKunjin, Ross River, Murray Valley Fever; Japanese, St Louis, Eastern, Western and EquineEncephalitis. New Zealand has mosquitos that are capable of transmitting many of these diseases inthe lab and there are doubtless viremic travelers bringing them into the country, but thus far there havenot been any infections contracted here. Climate change increases transmission of mosquito bornediseases. West Nile Virus is a case in point. Infection is most often subclinical, one in 5 have a selflimited febrile illness, and 1 in 150 develop neuroinvasive disease with encephalitis or poliomyelitis.Survivors of this severe form frequently have lasting neurologic deficits. WNV first appeared in theUS in NY in 1999 and in 4 years had spread across the country. Climate change has been implicated inthis rapid spread. Researchers matched 16,000 confirmed cases from 17 states with weather datashowing increased rates of infection with increased temperature and heavy rainfall. Warmertemperatures extend the mosquito breeding season, decrease time to maturity, and speed multiplicationof virus so you get more mosquitos who are more likely to bite, and each bite is more likely to infect.DENGUE Dengue is another mosquito borne viral infection reemerging in the US and Australia.According to the WHO dengue is the most rapidly spreading mosquito borne infection in the world.Dengue, sometimes called “breakbone fever” due to intense joint pain, has 3 clinical syndromes.Dengue Fever, a severe flu like illness with arthralgias; Dengue Hemorrhagic Fever for which theclinical hallmarks are thrombocytopenia and hemorrhage, and Dengue Shock Syndrome with thirdspacing of fluid into the lungs and peritoneum, hypovolemia and hypotension. The US and Australiaeradicated dengue by mosquito control measures but it has returned. The US has had 11 outbreakssince 1980 and a tripling of hospital admissions from 2000 to 2007, and Australia has had 40outbreaks since 1995.DENGUE SPREAD shows the spread of dengue in the Americas in recent years from the warmestregions around the equator to the warming regions to the north and the south
AEDESIn addition to effects on breeding and biting of mosquitos mentioned before for WNV, climate changeis increasing the geographic range of dengue mosquito vectors. Researchers at Wellington School ofMedicine and the Univ of Waikato developed a computer program to predict the effect of climatechange on the expansion of exotic mosquito populations, in New Zealand including those thattransmit dengue. Aedes aegypti, or Yellow Fever Mosquito, is the most efficient vector for dengue. Itlives only in tropical and subtropical climates because it cant survive cold winters. Aedes aegypti couldnot live in NZ today. But by 2050, increased rainfall and warmer temperatures will provide conditionsin which it could thrive. Dengue is also transmitted by Aedes albopictus, the Asian Tiger Mosquito, anaggressive daytime biter and invader of territory around the world which can survive winter freezes andin the US is found as far north as Chicago. Both egypti and albopictus are daytime biters, so bed netsare ineffective for prevention. Albopictus has been intercepted at least 11 times at NZ North Islandports. If it were to get past Biosecurity, it could establish right now in Northland. With future climatechange it could find expand along the entire coastline of the North Island and in very warm years evenreach the South Island. In addition to dengue, albopictus is a vector for Yellow Fever and Ross RiverVirus. Immuno-naive populations are extremely vulnerable to arbovirus epidemics. In 1979 RRVentered Fiji via an infected Australian tourist causing an outbreak of 50,000 cases and then spread toother islands ultimately infecting over 500,000 people.AMOEBIC MENINGOENCEPHALITIS is a rare infection affecting healthy children which isalmost 100% fatal. In NZ Naegleria infection is a consequence of immersing the head in thermal pools.In the US weve also seen cases from swimming in warm southern lakes, but the child in this photo wasthe first one to die of amoebic meningitis after swimming in a lake in Minnesota, 500 miles north ofany previously diagnosed infection. The map needs updating now that a second Minnesota child hasdied. NZ doesnt have long temp records for its lakes but measurements in Lake Taupo show it haswarmed almost 1 degree since 1970 and NZ rivers have also warmed slightly over the last decade. Lowwater levels during droughts will increase seasonal water temperatures and the risk of amoebicmeningitis for young swimmers.MASS DISLOCATION In the US since 2005 over 7 million people have been evacuated fromtheir homes due to extreme weather events. One big lesson from Katrina was that the biggest healthimpact was not illness or injury from flood waters, but people with chronic diseases decompensatingbecause they were disconnected from their usual source of care. Outbreaks of communicable diseaseare also common in shelters where large numbers of people live in close quarters. Aside from thephysical consequences, these experiences leave emotional scars : 30% of people affected by major firesand hurricanes develop symptoms of Post Traumatic Stress Disorder.Worldwide, environmental events now create more refugees than war and genocide. Poorer countrieswill bear the brunt of climate change and some of their refugees will come to NZ bringing diseases ofpoverty with them. Asia and the Pacific Islands are considered to be one of the areas most vulnerable toclimate change. By 2050 over 100 million of their inhabitants will be displaced by rising seas, failedcrops, and extreme weather. Asia and the Pacific Islands also have one third of the worlds MDR TBand Asian -Pacific Islander immigrants to the US are 20 times more likely than Europeans to developactive tuberculosis in their new home country.POLLEN CO2 acts as fertilizer, especially for weeds and increases pollen production. The graphshows ragweed pollen production with preindustrial, current and future CO2 levels. High pollen levelscause flare ups of allergies and increased ER visits for asthma. New Zealand has one of the highestprevalances of asthma and allergic disease in the world and rising rates of hospitalization for asthmaexacerbations.Climate change is also increasing the length of ragweeds flowering season and itsallergenicity and increasing the geographic range of common allergenic plants.
OZONE Ground level ozone, commonly called smog, is a potent respiratory irritant. It is formedwhen nitrogen oxides and VOCs combine in the presence of sunlight. The warmer and sunnier theweather, the more ozone is produced. New Zealand generally has good air quality and even Auckland,which has the worst air quality in the country, has levels of ozone below the safety standards set by theMinistry for the Environment. Thats great for people who dont have asthma, but increases in groundlevel ozone, even when they remain below environmental standards, make asthma worse. Studiesshow that ozone increases reactivity to dust mites in adults and use of beta agonist medication inchildren. Warmer temperatures would increase ozone levels in Auckland and adversely affect peoplewith asthma. Since 1 in 6 adults and 1 in 4 children in New Zealand are asthmatic, even a small effectcould have large consequences.DROUGHT Drought is becoming more frequent in NZ. In the US, farmers in drought affected areashave increased rates of suicide. Climate change is expected to increase the frequency and severity ofdrought, especially in Canterbury, Otago, and Northland.HUNGER Crop failures raise food prices. At the moment, the round of extreme weather events inAustralia has increased the price of fruit and veg in NZ. In the last national nutrition survey, 40% ofNew Zealand households were moderately to severely food insecure. Price increases worsen foodinsecurity and health: Kids from food insecure families are more likely to be hospitalized and in poorhealth. Iron deficiency anemia, which is associated with poor school performance and irreversibledevelopmental deficits, is 11x more common in preschool children from food insecure households, and8x more common in primary grades. Food prices determine not only how much but what kind of foodpeople eat. Food insecure adults fill up on cheap empty calories and have increased rates of obesity anddiabetes. In addition to its general impact on the poor, droughts disproportionately affect the nutritional,spiritual, and mental health of aboriginal people who depend on fishing and gathering as part of theirtraditional diet and the nutrition of rural residents who depend on fishing and hunting as sources ofprotein.AUSTRALIAN DUST/AUCKLAND Loss of surface vegetation during droughts leads to desertexpansion and dust storms. Dust emissions in Australia have doubled since the 1990s. Big Australiandust storms like the ones in 2009 increased particulate levels in the northern half of the North Islandand the West Coast of the South Island. Elevated particulate levels are associated with worsening ofasthma and COPD. In Asia, increased admissions for heart and lung disease are seen for up to monthafter dust storms and studies show transiently decreased pulmonary function in children.VALLEY FEVER Dust storms carry bacteria, fungi, toxins and heavy metals. In Africa dust stormsare followed by huge outbreaks (like 250,000 people) of meningococcal meningitis. In California andArizona we are seeing epidemic level increases of coccidiodomycosis or Valley Fever, a fungalpneumonia caused by inhaling dust containing fungal spores. Another effect of dust storms in the USis an increase in MVAs due to low visibility.GROUNDWATER TOXICITY Droughts increase the concentration of contaminants in groundwater, affecting those who get their drinking water from public and private wells. Nitrate is the mostcommon contaminant in NZ. As you can see from the map, elevated nitrate levels are widespread.Areas at high risk are those with shallow aquifers and high levels of agricultural nitrogen input.Elevated nitrate intake in pregnant women results in increased rates of miscarriage and congenitaldefects. In babies under 6 months, gut bacteria convert the nitrate to nitrite causingmethemoglobinemia, or blue baby syndrome. Long term exposure has been associated with bladderand gastric cancers.WAIKATO WATER CONTAMINANTS Here are the most recent groundwater test results forWaikato. The community source well samples were all taken at schools.
BUSH FIRE Climate change has increased the frequency and size of wildfires. Wildfire smokecontains potent respiratory irritants, carcinogens, nitrogen oxides, VOCs, and fine particulates. Fireecologists predict that climate change will cause more severe fire weather and fire danger, especially inthe Bay of Plenty, the east of both islands and the central Wellington and Nelson regions. By 2080the fire risk will more than double for Gisborne, Napier and Christchurch, and the high risk timewill be a month longer.The biggest health impacts from fires are from fine particulates. An active wildfire can release as muchas a ton per minute. During the 2008 Northern California fires, fine particulate levels in theSacramento Valley were 7 times higher than the EPA hazard limit. Fine particles cause upper andlower airway inflammation and can pass from the alveoli into the bloodstream. Studies examininghospital records during and after fires show a rise in ER visits, admissions, and deaths for asthma,bronchitis, pneumonia, MI, and CVA, particularly in the elderly. Studies following the 2003 SoCalfires showed a 34% increase in hospital admissions for respiratory conditions, primarily among thevery young (under 5) and very old, and decreased birth weights for babies exposed in utero in anytrimester. Fine particulates from fire are more toxic to the lungs than those from other air pollution.Researchers exposed mice to particulates collected during the 2008 California fires and found increasedprotein and leukocytes and decreased macrophages on pulmonary lavage compared with equal dosescollected from urban sources.ER VISITS NORTH CAROLINA This slide is from an EPA study comparing emergency room visitsfor cardiopulmonary diagnoses in rural counties exposed to smoke from a peat bog fire (the blue dots)with comparable counties ( the white dots ) not affected by the fire.COMBINED SEWER OVERFLOW Combined sewer overflow is a type of sewer system where thesame pipes that carry away our raw sewage do double duty for storm runoff. 700+ cities in US with 40million people have CSO systems.. When there is heavy rain, these systems are overwhelmed and thewater, mixed with sewage, overflows: into streets, rivers and lakes. Auckland and Whangarei dumpraw or partially treated sewage in their harbors with heavy rainfall. The health consequences can besevere. In Milwaukee in 1993, a city water plant with its intake near a Combined Sewer Overflowoutlet in Lake Michigan, got contaminated with cryptosporidium, sickening 400,000 people.GASTROENTERITIS This is why the majority of drinking water contamination cases in urbanwatersheds and nearly 70% of all gastroenteritis outbreaks occur after heavy rainstorms. In 2011, NZhad 45 such outbreaks of gastroenteritis from contaminated drinking water. Last year Darfield had125 cases of campylobacter linked to drinking water contamination associated with heavy rainfall.Children are the ones most likely to get severely ill. This slide shows how childrens visits to theemergency room for gastroenteritis (black line) match up with a model based on heavy rainfall (blueline).Hospital admissions of kids with diarrhea triple after heavy rain.FLOODS due to heavy rain are the most frequent natural disaster in NZ and these will become morefrequent. Coastal flooding and storm surges will increase in the future due to sea level rise and morepowerful storms fueled by warmer ocean temperatures. By 2030 sea level is predicted to rise about 18cm, doubling to tripling the risk of 100 year floods. Sea levels will rise up to a meter by the end ofthe century and flooding is predicted to increase 5 to 20 fold.MOLD Mold is a major health hazard in the aftermath of flooding but it doesnt always take floods togrow mold. New Zealands 89,000 leaky houses, are vulnerable to mold from heavy rainfall. TheUniversity of Otagos Housing and Health Program estimates these homes result in an additional
$26 million in health costs every year. Mold exposure triggers exacerbations of allergies and asthma. Itmay be a cause of asthma as well. A researcher at University of Cincinnati has been following a groupof children at risk of asthma due to their family history. He found that children exposed to mold in thehome as infants had 3x higher rate of asthma by age 7.LEPTOSPIROSIS Leptospirosis is an infection which causes hepatitis and acute renal failure that istransmitted to humans when the urine of infected animals comes into contact with broken skin or intactmucous membranes. Reservoirs include wild mammals, livestock, domestic pets and rats. NZ hasexperience with this as an occupational disease of farmers and meat handlers, but most casesworldwide are caused by contact with flood waters or runoff contaminated with animal urine. InCalifornia lepto is considered an emerging disease with a small but increasing number of human casesin the past decade resulting from recreational contact with contaminated water. Even with recentvaccination programs, lepto is endemic in livestock and working dogs in New Zealand, who present aready reservoir for transmission to humans in the aftermath of heavy rains.You may have noticed that the old, the young, people with cardiopulmonary disease and diabetes suffermost from climates health impacts because they are more sensitive and less able to adapt. They are likethe canaries in the coal mine whose deaths warned warn miners to ascend when there were toxic levelsof carbon dioxide underground. But when our canaries, our children and our parents, get sick from toomuch carbon dioxide, we have nowhere else to go.DIAGNOSIS: ITS US We have met the enemy and he is us. Were burning so much fossil fuel thatweve overwhelmed our planets capacity for homeostasis. Right now about 25% of the CO2 we emitdissolves in our oceans (which are 30% more acidic as a result) and another 25% is absorbed by ourforests but the other 50% goes into atmosphere, forming a blanket around the earth which traps thesuns heat. How do we know its not a natural fluctuation? Here is a record of CO2 levels looking back600,000 years and you can see that they now are by far the highest they have ever been.PROGNOSIS Whats the prognosis looking forward? (Review each graph in detail in your ownwords) In best case, CO2 levels stabilize, they dont come down for thousands of years. Temperaturekeeps rising (use oven preheat analogy) but tops out at 2-3 degree C increase. In worst case, emissionsand atmospheric levels rise and temperatures increase for 4-6 degrees C.PUBLIC HEALTH EMERGENCY Unfortunately were following the worst case scenario and arefacing what The Lancet has called the greatest public health threat of the 21st century. Its a public healthemergency, not because everyone will drop dead tomorrow, but because if we dont act now, it will betoo late. Carbon dioxide is the gift that keeps on giving. What we put in the atmosphere today andtomorrow will keep warming our planet and making people sick for hundreds to thousands of years.So is there anything we can do? Yes. Chronic disease analogy.HOT GLOBE As doctors we have an important role to play in developing a rational response toclimate change. We are trusted and respected members of our communities. We have a long historyof acting to protect the publics health. And we have a skill we take for granted which is in shortsupply out in the world: the ability to translate science into everyday language. We must help thepublic and policymakers understand that climate change is affecting our health here and now; that if wecontinue business as usual, the future will be catastrophic; and that we will not be able to adapt toepidemics and contaminated air, food and water.PUMP Some of you may thinking now about ways to shrink your personal carbon footprint butindividual lifestyle and consumer choices are too little too late. We have 18 years to cut our greenhousegas emissions in half or face the worst case scenario. Theres only one way to bring about that kind ofchange and thats as a society together.
This is the water pump in London made famous by Dr. John Snow, who has been called the father ofpublic health. Back in the 1800s during a cholera outbreak, Dr Snow mapped the homes of the choleravictims and traced the source back to this pump. So what did he do? Did he go from door to doortelling people not to drink the water? No. He took the handle off the pump. Thats how you treat apublic health emergency. To take the handle off the pump we need public policy that lowers greenhousegas emissions as quickly as possible. Ive only been in NZ a month and would not presume to tell youwhat policies you need, but Ill share what doctors are doing in the US. We are organizing to support 3national policies. First, for our EPA to regulate CO2 as a hazardous pollutant. Second, Governmentinvestment in public transit and ACTIVE TRANSPORTATION. This is a win win proposition.The health benefits and savings would be enormous. We know that cities and countries with higherrates of biking and walking to work have lower rates of obesity, diabetes, and hypertension. Peoplewho live in walkable neighborhoods weigh an average of 10# less than residents of more dispersedareas. A10 lb weight loss cuts the risk of diabetes, heart disease, and breast cancer in half. Mass transitis also active transit because we walk to and from the station. When Charlotte NC put in a light railsystem they did a before and after study and found that new rail commuters lowered their risk ofobesity by 80%.NHS SAVINGS This shows the anticipated savings to Englands National Health Service from a planto increase active travel just in London. In Kiwi currency thats 1.5 billion dollars.Finally we need to make our homes and workplaces energy efficient and speed the transition toclean energy.Let me tell you a story about a nonprofit hospital system in the US which is about the size of WDHB.They have 40 primary care clinics, 3 regional hospitals, a tertiary teaching hospital with 300-somebeds, and 6000 employees. In the US, health care is responsible for 8% of our greenhouse gasemissions. This hospital decided that being big CO2 emitters was incompatible with their mission toimprove the health of their communities. In 2008 they developed a strategic plan to power theirfacilities with 100% clean energy by 2014. First they improved their energy efficiency, reducingenergy use by 20% and saving over a million dollars a year in utility bills. Then they set up cogeneration projects with a local brewery and county landfill. They put up solar panels, bought a windfarm, joined with local dairy farmers to buy a manure biodigester, built a new sustainably designedfacility, and are on track to meet their goal of 100% clean energy next year. And they are prospering. Itcan be done and its up to us to choose which future we want. We can take the handle off the fossil fuelpump and get the climate crisis under controlOR WE CAN CONTINUE BUSINESS AS USUAL and end up in a world that is 4-6 degrees warmer.All the health effects Ive told you about are happening with a global temperature rise of less than 1degree. Imagine 6 degrees and remember that when we release CO2 into the atmosphere, werechoosing the future and we cant take it back.If you still arent sure about the dangers of climate change, take time to research it for yourself.The risk is far too great to just wait and see. If youre convinced we need to address the climatecrisis, join Ora Taiao, the NZ Climate and Health Council. Their website and a contact email areon the slide. If you are ready to speak out, start giving this presentation or one like it for yourcolleagues or your community. You can find the link to download my slides and notes at thewebsite of our US doctors group Climate 911 or look for them on Slideshare. Thanks for yourattention and Im happy to answer any questions.NO PLANET B