NewYork:Oxford Summary Measures of Population Health: Concepts order vardenafil 10 mg without a prescription erectile dysfunction 60784, Ethics buy 20mg vardenafil free shipping erectile dysfunction at the age of 20, Measure- University cheap vardenafil 20mg with visa impotence vitamins. World Mortality in 2000: Life Tables for 191 Empirical Validation, and Application. Mauritius Health Sector Reform, National Burden of from Tobacco in Developed Countries: Indirect Estimates from Disease Study, Final Report of Consultancy. Report of the Ad Hoc Committee on Health Research United States Department of Health and Human Services. World Health Report Collaboration with the Pan-American Health Organization, Department 2002. Measuring the Global Burden of Disease and Risk Factors, 1990–2001 | 13 Part I Global Burden of Disease and Risk Factors Chapter 2 Demographic and Epidemiological Characteristics of Major Regions, 1990–2001 Alan D. Lopez, Stephen Begg, and Ed Bos Health status is both a determinant of population change, between age and mortality and morbidity. Second, each largely through population aging, and a consequence of of the dynamic processes inﬂuencing population size and population growth, with smaller family size associated with growth, structure, and distribution, namely, fertility, lower mortality, and of economic and social development. Thus, Studies of the interrelationship between demographic any discussion of disease control priorities and of the trends and health have typically focused on health as the health system for delivering interventions requires an independent or determining variable. Indeed, a population’s understanding of the demographic context and how it is health status inﬂuences all components of population changing. In addition to the obvious direct effect of individual This chapter begins by providing an overview of global health status on mortality and morbidity, it has a direct population trends in each major region of the world and the impact on fertility, largely through improved child survival, current size and composition of the population. Given this but also through the biological capability of a sick woman volume’s focus on the descriptive epidemiology of diseases, to bear children. Processes such as screening potential injuries, and risk factors, we then examine trends in mortal- migrants for disease are also mechanisms whereby health ity over the past decade in more detail as background status exerts a direct impact on population change, and thus against which the current assessment of the disease burden on population size and composition. This includes both an In contrast, demographic variables inﬂuence health assessment of trends in age-speciﬁc mortality and summary through two interrelated phenomena. First, a population’s measures of the age schedule of mortality, such as life size, composition by age and sex, and geographical distribu- expectancy and the probability of dying within certain age tion have a direct inﬂuence on overall health status. Age has ranges, as well as a speciﬁc discussion of trends in the main a particularly marked effect on the pattern and extent of ill- causes of child mortality. In addi- child mortality should remain a priority for global health tion to total population, the baseline assessment includes a development efforts, and the moral imperative to do so breakdown of population by sex and age (in ﬁve-year aggre- remains as relevant today as it was 30 years ago, when efforts gates). Fertility is speciﬁed as age-speciﬁc fertility rates for to improve child survival became increasingly organized females and mortality rates are based on survival probabili- and focused; and (c) the resulting emphasis by the global ties from life tables. Age-speciﬁc patterns of migration are public health community on reducing child mortality has also incorporated for countries in which migration ﬂows are yielded vastly more epidemiological information that can be observed or are thought to occur. It does and sex structure of the population and its rate of growth not provide information about the adjustments made to and comparative measures of fertility and mortality. Basic information on population size and composi- tion is available for most countries for 1990, and with the Sources of Population Data and Methodology exception of Sub-Saharan Africa, for 2000 (or thereabouts) as well (table 2. Around both dates, censuses covered The population and mortality estimates for various regions more than 90 percent of populations in all the regions summarized here are based on different data sources and except Sub-Saharan Africa. Lopez, Stephen Begg, and Ed Bos the model pattern, in which case the country-speciﬁc pat- size, with East Asia and the Paciﬁc accounting for about tern is followed (United Nations 2003). Thus,abouthalf theworld’spopulation on the basis of the cohort component methodology. This live in the low- and middle-income countries of these two approach applies estimated trends in birth and death rates regions. The smallest region in terms of population size is the and migration by age and sex to a baseline age and sex struc- Middle East and North Africa, with just 5 percent of the ture. Just over 10 percent of the world’s popu- age-speciﬁc fertility and mortality rates and migration and lation live in Sub-Saharan Africa. Another 15 percent live in the size of the initial age groups (base year population) high-income countries, a proportion that is declining. While many other factors contribute to mortality gates are thus weighted by the different population sizes of and fertility levels, the age distribution of a population is an individual countries. As a result, the with almost 45 percent of the population of Sub-Saharan age and sex structures reported here, as well as any indica- Africa being younger than 15, compared with 20 percent of tors derived from them (such as crude birth and death rates) the population in high-income countries, where fertility are not strictly internally consistent. As a result, the large, however, as the estimated age-speciﬁc mortality rates median age of the population has increased in all regions. Population Size and Growth These changes in the relative age distribution of popula- Between 1990 and 2001, global population increased from tions since 1990 reﬂect changes in the growth rates of dif- about 5. During the decade,the growth rate Middle East and North Africa), as well as the world as a in developing regions ranged from 0. The highest growth Estimates at the global level conceal large differences in rates during this period were in the 40- through 55-year-old population growth among regions, which in turn consist of age group and among those over 70. Europe and Central Asia, where the impact of the regional The World Bank regions (see map 1 inside the front cover conﬂicts in the early 1990s on demographic structure is of this volume) vary substantially in terms of population particularly evident. Demographic and Epidemiological Characteristics of Major Regions, 1990–2001 | 19 Table 2. Along with the progressive aging of the population, the relative to females accounts for the sharp decline in the pop- relentless trend toward increasing urbanization has contin- ulation sex ratio after age 50 or thereabouts. Almost half the bers of males and females in the population, with the pro- world’s population lived in urban areas in 2001, up 4 per- portion of males being slightly higher in Europe and Central centage points from 1990. The increase in urbanization was Asia and in the high-income regions (51 to 52 percent) than particularly marked in East Asia and the Paciﬁc (increase in East Asia and the Paciﬁc and South Asia (49 percent). Overall, 42 percent Fertility of the population in low- and middle-income countries now live in urban areas. Differential mortality fertility levels vary a good deal among regions, all low- and and, to a limited extent, migration, shape the sex ratio at middle-income regions witnessed large declines in fertility other ages (ﬁgure 2. Overall fertility levels in low- and girls and for women during their childbearing years leads at middle-income countries fell by almost 20 percent over the ﬁrst to an increasing and then to a constant sex ratio to decade,a remarkable decline,with levels falling by as much as about age 45, after which male mortality is higher. Excess 33 percent in the Middle East and North Africa, and even by mortality of adult males in Europe and Central Asia explains 10 percent in Sub-Saharan Africa. However, fertility rates in the particularly low sex ratio observed there (Lopez and Sub-Saharan Africa remain high, with the total fertility rate others 2002). Fertility is below replacement levels (about broad categories depending on the available data: direct esti- two children) in all but ﬁve high-income countries (Brunei mation from complete vital registration, estimates from Darussalam, Israel, Kuwait, Qatar, and the United Arab vital registration corrected for undercounting, and estimates Emirates), as well as in most countries in Europe and Central derived from models based on child mortality levels. When fertility drops to below replacement levels, popu- Mathers and others (2005) review the availability and qual- lationgrowthoftencontinuesforseveraldecades,asthenum- ity of mortality data and group the 192 member states of the berof birthsexceedsthenumberof deathsbecauseof thehigh World Health Organization into broad categories according proportion of women of childbearing age. The approximately 40 percent of remaining coun- mortality by sex across regions contribute to the variable tries either have no recent data or no data at all that can be pattern of population sex ratios described earlier. The used to estimate causes of death or the level of adult mor- theory of demographic transition suggests that the rapid tality directly. To help interpret vival by the global public health community have yielded the broad regional demographic patterns described earlier, a either direct or indirect estimates of child mortality for all but review of trends in mortality and the causes underlying such a handful of countries (Hill and others 1999; Lopez and trends is useful. Based on a careful review of the time trend of Demographic and Epidemiological Characteristics of Major Regions, 1990–2001 | 21 Low- and middle-income countries East Asia and Pacific Europe and Central Asia 80 60 40 20 0 Latin America and the Caribbean Middle East and North Africa South Asia 80 60 40 20 0 Sub-Saharan Africa High-income countries World 80 60 40 20 0 5 0 5 5 0 5 5 0 5 Average annual percentage change Average annual percentage change Average annual percentage change Source: Calculated from United Nations 2003. These countries include China unavailable for only about 10 countries that together account and India, where application of such methods suggest that for about 2 percent of child deaths (Lopez and others 2002).
There is simply no evidence taking this will not offer you a high to show that these therapies work buy vardenafil from india erectile dysfunction biking. These plants also Parkinson’s disease is a very active do not have carbidopa (see page area of research discount 20mg vardenafil with amex erectile dysfunction treatment psychological causes. At early stages of Parkinson’s order vardenafil now erectile dysfunction cause of divorce, In general, it depends on the type of wearing-off or “off-times” (see treatment you have. For this levodopa, you should notice clear reason, you do not have to take your improvement in your movement and medication on an exact schedule. You can continue to improve tremor (although not always do this, as long as your medication at lower doses). If you do not, then your treatment (or diagnosis) may need to If you do start to notice “off-times”, be changed. This will help The other dopamine medications also prevent any wearing-off, so you can help, but the difference may not be as have better control of your symptoms dramatic. There is no one set rule for this, and it depends on Usually it is best to take pills an how the medications affect you. You will just need to keep in might: mind that its effect may not be as strong this time. Another option to consider is a smart phone application, which can set up reminders for you. For this reason, you might not notice any difference if you have not taken Not necessarily. Your body tends to be would slowly notice your symptoms able to ‘store’ medication to have a coming back and getting worse with more long-lasting effect. Finally, you might begin to notice more non-motor symptoms over time Should I save them for when I’m (e. These changes cannot No, do not stop taking your be treated with dopamine medication. Dopamine medication works very well Studies have shown no benefts to for people with Parkinson’s. Treatment as the disease advances over time is there to help you to carry out your and more of your dopamine neurons daily activities, so you can lead a age, you will need a stronger dose fulflled and productive life. You may also not be possible if we stop or delay need to take your medications more treatment. However, at that point, there will be other It is true that on average if you treatments you can consider delay levodopa (that is, start other with your doctor to control medications frst), you get dyskinesia this. For young people, we and fuctuations later (see page sometimes start with other 44-49 to learn more). However, since medications (see page 54-57 these medications are less effective, to learn more), especially if your you would also have less control symptoms are relatively mild. Keep in mind that dyskinesia is a sign that your Research has shown that all people treatment is working well, (just a bit need levodopa and that delaying ‘too well’ in this moment). If anything, it only makes your dyskinesia right away: quality of life (your overall level of • If you are 70 or over when your health, comfort and well-being) Parkinson’s started, it is not slightly worse. In other words, putting likely that dyskinesia will ever be up with disability for years to save a a big problem. Is levodopa toxic to my dopamine doses of dopamine medications for over 30 years), no nerve cell damage neurons? When levodopa was frst It can sometimes feel as though these developed, people wondered if medications are making you worse. This is because, over time, you need However, over time, it has become more and the disease is continuing clear that this is not true. However, this has to do people who were wrongly diagnosed with the disease changing, not your with Parkinson’s (and took very high medications doing damage. Can dopamine treatments slow It is only in situations where people received very poor treatment (and the progression? That said, we are a very long way off from putting stem cells inside Stem cells (also known as the ‘cells of you to replace missing cells. We of youth’) are cells that are not yet cannot simply place stem cells into specialized. This is because stem cells and divide, and have the potential to have to: become any type of cell in your body, • Survive your immune system (including a nerve cell). We are even now able become part of your current to make stem cells grow from adult brain network (and without tissue. So, Also, Parkinson’s disease affects unless there is a major, unexpected many areas of the brain. So, placing research breakthrough, it is not stem cells into only one area may not likely that you will have implanted help much. Still, there may be other, research over the last 25 years has unexpected ways that stem cells will be useful in the future. Does that mean there will be • protect the energy burning centers of your cells (called no new treatments to slow the mitochondria), progression? Researchers are: Some of these treatments might eventually dramatically change • testing ways to reduce synuclein the way that Parkinson’s disease (a chemical in your brain that is progresses over time. These linked with Parkinson’s) levels in treatments are already being tested your brain with Parkinson’s patients. So, • stop synuclein from sticking although we cannot know what will together to damage neurons happen, this is still a very exciting time in Parkinson’s research. It is really up to you to decide when you want let others know about your diagnosis. Your decision to tell others at work will depend on: Finally, keep in mind that in some • Your relationship with co-workers professions you must inform your and employers employer (mandatory disclosure). However, in harsher or highly- competitive work environments, Remember, being diagnosed with employers and coworkers may use Parkinson’s does not mean that your diagnosis as an ‘excuse’ to pass your career or work life is over. If you over for promotions or give you your medication is giving you good less interesting tasks. There are many reasons • Good distance judgment to be cautious about driving, such as: • slow reaction time or reactive • No trouble with memory and movements concentration • problems with perception (i. Also, if you are still driving, ask leep attacks while behind the a friend of family member to sit in the wheel) passenger seat and watch you. Usually, you should be able to drive safely if you have all of the following: Remember, Parkinson’s sometimes impairs your ability to stay awake, • Mild motor changes (that is, even causing sudden sleep attacks. Even if you normally drive well, never drive when you are • Good balance and can walk feeling ‘off’ or even a bit sleepy. Most government authorities require that you report any changes in your health situation.
Many die 3 Vector-Borne Infections – Primary Examples within their frst week of life buy vardenafil 20mg online erectile dysfunction treatment online, but some can persist almost indefnitely generic vardenafil 20mg with amex erectile dysfunction johnson city tn. They are limited by the damage that accumulates on their non-repairable wings and ap- pendages and do not age as much as they wear out 10mg vardenafil amex young person erectile dysfunction. Predation, desiccation and entrapment in water probably kill more mosquitoes than any other cause. West Nile vectors on the East Coast of the United States that emerge in August of one- year can over winter and become active in May of the following year for a lifespan of at least nine months. This becomes troublesome when we realize that their pro- gramming is also diverse and adaptable. Because the programs of Vectors shouldn’t be individual mosquitoes difer slightly from each other and only thought of as mere dumb the best programs survive long enough to produce progeny, their vessels or fying hypodermic programs are always getting better and adapting to changing con- needles. Like the Red Queen’s race in Alice in Wonderland, just think of them as tiny, well- to keep up, vector control operators must similarly adapt their programmed robots. Vectors, Specifcally Mosquitoes and ticks account for the majority of transmissions of the most important vector-borne diseases, although some close relatives of mosquitoes also get involved, including sand fies and black fies. Each of these organisms has unique habitat requirements and feeding behaviors, which can vary greatly, even within a closely related group. For example, dozens of species of Anopheles mosquitoes can transmit malaria around the world. The specifc habits of vectors provide the keys to controlling them and preventing them from spreading infection. Only the female mosquito can transmit disease because only she, and not the male, has the knife-like mouthparts needed to extract blood from her victims. Their bodies are so small (3 mm) they are hard to detect until after they begin biting. Unlike mosquitoes, black fies feed by slashing through the skin, and they never feed indoors. They can attack in such large numbers that their salivary fuids alone can cause a person to become ill, causing a condition called “black fy fever. They are typically found in structures with thatched roofs that ofer hiding places during the daytime. They are called “kissing bugs” due to their predilection for feeding on the soft skin of people’s faces, including lips. After feeding on the victim’s blood this insect releases its infected feces near the bite wound. Hard ticks feed only a few times during their lifespan, which tends to limit their odds of acquiring an infection. Never- theless, the longevity and host selectivity of hard ticks allows them to be relatively efcient vectors. Diseases vectored: Tick-borne Encephalitis, Lyme Disease, Tick-borne Relapsing Fever 5 Vector-Borne Infections – Primary Examples Important Vector-borne Diseases 1. Malaria Malaria exists in every tropical and subtropical landscape across the globe, some- times making seasonal excursions into temperate areas as well. The protozoan parasites that cause it have more complex genomes, metabolisms and life cycles than almost any other vector-borne threat. This complexity makes them a dif- fcult target for interventions such as drugs and vaccines because the parasite’s shape-shifting ways allow it to evade chemical and immunological defenses. They pose a moving target as well, intentionally changing their outer coating during each phase of their life cycle, and creating a diverse antigenic and metabolic ward- robe through sexual recombination, an engine of diversity creation unavailable to simpler microbes such as viruses and bacteria. Malarious Regions of the World Malaria endemicity Very high High Moderate Low No malaria Malaria is present in more than 100 countries, and imposes an economically signifcant burden on the populations of at least 80. Four species of parasites afect humans, but two of them, Plasmodium falciparum and P. In local populations most deaths occur in children between 6 months and 2 years old. The immune evasive- ness of malaria parasites prevents complete immunity from developing, but older children and adults who have experienced multiple infections, enjoy some level of protection from the most severe manifestations of the illness. Expatriates, tourists and urban dwellers share the immu- Dengue carrier, Aedes aegypti nological experience of an infant and thus remain particu- mosquito that has just taken a bloodmeal larly vulnerable to the life threatening aspects of this dis- ease. Certain complications, such as cerebral malaria, strike quickly, clogging small blood vessels in the brain to produce coma. Stories of expatriates falling ill on a Friday, putting of treatment till Monday and dying over the weekend are not uncommon. Tus, malaria prevention requires serious atten- tion when visiting areas where it is transmitted. Although no vaccine is currently available, prophylactic drugs and mea- sures that reduce exposure to night-biting Anopheles mos- quitoes, such as bed nets and repellents can be very efective. While malaria transmission occurs most frequently in rural areas, Dengue is a city disease. While the Anopheles vectors of malaria bite mainly at night, the Aedes vectors of dengue bite mainly in the Dengue is caused by one of daytime. Dengue fever can be painful (hence its nickname of “breakbone fever”) and Subsequent dengue infections debilitating but is generally not life threatening when frst acquired. Like malaria, dengue fever exists throughout the tropics, and seems particu- larly prevalent in Asia, the Middle East and Latin America, although poor report- ing in Africa may obscure its true prevalence there. Dengue in Africa appears to be mainly concentrated in the eastern half of the continent. No prophylactic drugs or vaccines are available to prevent dengue, but mea- sures that limit or prevent biting such as repellents or removal of water-bearing containers in which the mosquito vectors can breed does help. Arboviruses Dengue is not the only arthropod-borne virus (arbovirus) of concern in the world. A wide variety of often-dangerous viruses exist almost anywhere on the globe where mosquitoes are found. Although each of these individual viruses generally have restricted ranges and many afect relatively small populations, we consider them here as a group because of their collective importance. The following “rogues gallery” is far from exhaustive, but illustrates some of the more notorious pathogens as well as those that are currently in the news due to resurgence or expansion of their boundaries. Ch i k u n g u n y A Chikungunya tops this list because of its recent resurgence in places like India, Sri Lanka, Mauritius and countries in Europe involved in frequent tourism to these destinations. Concern has recently arisen that it will soon increase its range in Europe due to the spread of Asian Tiger mosquitoes (Aedes albopictus), which can act as signifcant vectors for this infection. Infection with chikungunya can be severe and temporarily debilitating but is generally not life threatening in otherwise healthy people. It is mainly transmitted by day-biting Aedes mosquitoes and can cycle in both urban and rural areas. In its rural incarnation, monkeys serve as maintenance hosts and tree-hole and bromeliad breeding mosquitoes transmit it.