Bringing chronic disease epidemiology and infectious disease epidemiology back together

Quantitatively estimated the global burden of disease of chronic and infectious diseases interface in 2002

Work, Health, and COVID-19

Health-care provision for displaced populations arriving from Ukraine

The Real Millennium Bugs

Chronic non-communicable diseases have become a major threat to humanity. International studies have shown that of 57 million deaths worldwide in 2008, 36 million (63%) were caused by chronic non-communic- able diseases; of these, 29 million (80%) occurred in low and middle income countries. The WHO predicts that if the current trend continues, the annual number of deaths due to chronic non-communicable diseases will increase to 55 million by 2030. Due to acceleration of industrialization and urbanization, along with population aging and rapid changes of people's lifestyle, the morbidity and mortality from chronic diseases are rapidly increasing in China. Therefore, dealing with the prevalence of chronic non- communicable diseases has become one of the current major health issues for China to address. On the basis of summarizing the status of major chronic diseases in China, analyzing the key issues and key factors in chronic disease prevention and control, and reviewing and summarizing the experience from the previous projects, this paper proposes the following recommendations as strategies for chronic disease prevention and control and development of relevant system, which China should adopt. All relevant government departments should formulate corresponding policies; establish a coordinated and efficient work system with rational structure and clear division of tasks and responsibilities within the system. Implementation and development of integrated medicine in system is necessary. Work norms and requirements will then improve the performance and efficiency in chronic disease preven- tion and control in China. of the 57 million deaths in the world in 2008, 36 million (63%) died of non-communicable chronic diseases. These chronic diseases include cardiovascular disease (48%), cancer (21%), chronic respiratory disease (12%) and diabetes (3.5%). Among the deaths from chronic non- communicable diseases, 29 million (80%) occurred in low and middle-income countries. In these countries, 48% of deaths are premature deaths (death before 70 years old); this is much higher than the 26% in high-income countries. According to WHO estimates, the deaths caused by non- communicable chronic diseases will increase to 55 million by 2030 if the current trend continues (The 66th World Health Assembly, 2013; The World Health Organization, 2013). Therefore, responding to the epidemic of chronic non-communicable diseases is an issue the developing world must urgently address.

The Central Harlem and Lower East Side districts of New York City are areas of low average economic status, the Central Harlem district being populated largely by Negroes, while in the Lower East Side persons of foreign birth or parentage predominate. Both districts are areas of high mortality, the death rate for all causes in each area in the period 1929–1933 showing an excess of approximately 4 per 1,000 over the rate for the entire City (1). In the same period, the tuberculosis death rate in Central Harlem was over three times as high as the rate for the City, exceeding the rate for all other health districts, and its infant and mortality rates were the highest observed. In the Lower East Side, mortality was excessive for diseases common to adults—the cardiovascular-renal diseases, cancer, diabetes, and pneumonia—reflecting the effect of the higher average age of its population. The high mortality rates and low average economic level common to the two districts assure comparability of the districts in respect to these factors. We thus have for experimental observation Negro and white groups in which certain variables are, to some extent, constant. The relative health status of the Negroes of Central Harlem and the predominantly foreign-born population of the Lower East Side as indicated by their illness rates is therefore of special interest. Data for such a comparative study were obtained in sickness surveys conducted by the United States Public Health Service and the Milbank Memorial Fund in the spring of 1933. The basic data for Negroes relate to 1,348 families in Health Area 12 of Central Harlem and were collected by the Milbank Memorial Fund in collaboration with the Emergency Work and Relief Bureau of New York City.2 Comparable data for white families were obtained in a sickness survey conducted by the United States Public Health Service and the Milbank Memorial Fund and relating to 7,436 families in poor areas of eight large cities, including 1,225 in the Lower East Side of New York City. A detailed description of the method and scope of the survey has been published previously (2). In both investigations a complete record of illness occurring during the three months prior to the date of the survey was obtained for each member of the family. The beginning dates of the three-month periods for the illness record extended approximately from December 20, 1932, to February 15, 1933. Information concerning continuity of employment, wages earned, and other income received by each member of the family was secured for each year from 1929 through 1932. The present report on the results of this survey in the Central Harlem and Lower East Side districts of New York City summarizes in part data previously published (3). Certain results of the survey of white wage-earning families in eight cities—Baltimore, Birmingham, Cleveland, Detroit, Pittsburgh, Syracuse, and New York City—are presented for comparison, including some data not previously published. The comparability of the surveyed groups in Central Harlem and the Lower East Side from the standpoint of occupational composition, economic level, and depression history is indicated by figures shown in Table 1, in which data for the total number of white surveyed families in eight cities are included for comparison. Skilled workers predominated among the wage-earners of the Negro families of Central Harlem and the white families of the Lower East Side. Both areas were affected similarly by the period of the economic depression, approximately two-thirds of the chief wage-earners in both districts being employed on full time in 1932, while the proportion of full-time workers in 1929 was between 80 and 90 per cent. The distribution of the surveyed families according to per capita family income for the year 1932 shows a somewhat higher proportion of the “poor,” and a lower proportion of the “comfortable,” in the Lower East Side than in the Central Harlem district (Table 2). In interpreting the Negro-white comparisons of morbidity, therefore, it should be remembered that the whites do not represent an “average” white group but were drawn from poorer areas. The disabling3 illness rate from all causes for the three-month survey period among Negroes of Central Harlem was 143 per 1,000 persons, this rate showing a small excess, 4 per cent, over the rate for the white population of the eight large cities, which was 138 per 1,000 (2). In the white population of the Lower East Side, the disabling illness rate was 157 per 1,000, representing an excess of 9 per cent over the Negro rate, and 14 per cent, over the rate for the eight large cities. When age adjusted rates are compared, the slight excess in the disabling illness rate of Central Harlem over the eight-city rate disappears, the age adjusted rate for Central Harlem, 136 per 1,000, being 1 per cent lower than the white rate for the eight cities combined. Age adjustment increases the rate for the Lower East Side to 159 per 1,000, which is 17 per cent higher than the age adjusted rate for Central Harlem, and 15 per cent higher than the eight-city rate. Variation with Age and Sex The above gross comparisons, however, conceal the true situation. The higher case rate in the Lower East Side than in Harlem arises in large part from the excess in rates for children under 10 years of age. The several groups of data used in this report suggest a fairly uniformly lower rate of sickness among Negro children under 15 than among comparable white children. It will appear later that the very high rate among surveyed children in the Lower East Side was due in part to the prevalence of measles in this area at the time of the survey. However, the rate for Negro children was lower than the average rate for white children in the eight cities. From Figure 1 it will be seen that after the age of 15 the case rates for disabling illness in Harlem were uniformly higher than those for both of the white surveyed groups. In the adult ages, rates for the Lower East Side show close agreement with those for the eight cities. The higher rates for Negroes accrued from the consistently excessive age-specific rates among Negro females. In fact, the rates of Harlem Negro males exceeded those among Lower East Side males only during the ages 15–24. (Table 3.) Expressed in summary fashion, the adjusted4 rate among Harlem males, 15 years of age and over, was approximately 12 per cent lower than among comparable white males in the Lower East Side and nearly 9 per cent lower than among adult males included in the surveys for eight cities. On the other hand, the corresponding sickness rate among Negro females 15 years of age and over in Harlem was 36 per cent higher than that observed among white women of comparable ages in the Lower East Side and about 28 per cent higher than that found for white females in the eight cities. Age-Specific Rate of Disabling Illness during a Three-Month Period in the Early Spring of 1933 among Persons in Negro and White Families in New York City and White Families in Eight Large Cities (Baltimore, Birmingham, Cleveland, Detroit, Pittsburgh, Syracuse, New York, and Brooklyn) The three surveyed groups showed the excess in the disabling illness rate for females, compared with that of males, which has been frequently observed. However, the excess in the rate for female Negroes in Central Harlem over that of Negro males was very much greater than the excess for females in both of the white groups. Disabling Illness by Cause The respiratory diseases were found to be the most frequent cause of illness in each of the three surveyed areas, the disabling illness rate due to these causes varying from 61, in the Lower East Side, to 72, in the Central Harlem district. (Figure 2 and Table 4.) For this group of diseases, the rate for Negroes thus exceeded the rates for both of the white surveyed groups. The digestive diseases and injuries due to accidents also appeared in higher rates among Negroes than among whites in the samples considered. On the other hand, the rate for the group of epidemic diseases among Negroes was notably low. In nonepidemic periods, Negro children appear to show low susceptibility to certain acute communicable diseases. In the Lower East Side, the rate for the epidemic diseases was over twice as high as that for the eight large cities; examination of the incidence of these diseases by specific cause indicated that measles was unduly prevalent in the area, the rate for this cause alone being 28.4 per 1,000 persons, compared with a rate of 6.0 per 1,000 for the Central Harlem district. Rate, during a Three-Month Period, of Disabling Illness Classified in Broad Diagnosis Groups: Negro and White Families in New York City and White Families in Eight Large Cities Surveyed in the Early Spring of 1933—Sole or Primary Causes Only Age Incidence for Certain Broad Disease Groups Classification of the disabling illnesses in broad disease groups according to age reveals certain important differences between the age incidence of certain diseases in the Negro and white surveyed groups. The figures, shown in Table 4, indicate that the excess in the disabling illness rate for respiratory diseases among the Negroes of the Central Harlem district arises from the higher Negro rates observed between the ages 25 and 54 years. The rates among Negro children were lower than among whites. This fact, together with the lower frequency of the epidemic diseases among Negro children, accounts for their relatively low incidence rate from all causes of illness, previously shown in Figure 1. The age-specific rates for Negroes for the group of chronic diseases, including the degenerative and nervous diseases, and rheumatism, show a slight excess over the white rates in the age periods 10 to 14 and 15 to 24 years. On the whole, however, the disabling illness rates for the chronic diseases among Negroes are low in consideration of their high mortality from certain of these causes. Illness Rates according to Income and Employment Status Although the total Negro and white groups represented in this survey were fairly comparable with regard to average low economic status, it is of interest to compare disabling illness rates between groups of Negroes and whites classified with respect to actual income5 and employment status. When this is done, as in Figures 3 and 4, several very interesting situations emerge. The occurrence of an epidemic of measles in the Lower East Side during the survey period resulted in an abnormally high illness rate. For the purpose of the subsequent comparison, the disabling illness rates for both the Negro and white population of New York have therefore been determined after the exclusion of illnesses due to epidemic diseases. Rate of Disabling Illness during a Three-Month Period among Persons Classified by Family Economic Status: Negro and White Families in New York City and White Families in Eight Large Cities Surveyed in the Early Spring of 1933. Rates adjusted for age. Illness rates are simple averages of rates in the eight cities. Rate of Disabling Illness during a Three-Month Period among Persons Classified by Family Employment Status: Negro and White Families in New York City and White Families in Eight Large Cities Surveyed in the Early Spring of 1933. Rates adjusted for age. Illness rates are simple averages of rates in the eight cities. From Figure 3 it is clearly evident that increase of sickness rates with lowering of income status holds true among Negroes as well as among whites. It also appears that the excess of Negro rates over those among whites does not persist in the groups classed as “comfortable,” but is restricted to those in the “moderate” and “poor” income groups. In the grouping of data with reference to employment status of wage-earners (Figure 4), it is seen that illness rates among Negro families consistently exceed those among white families of corresponding status. Nevertheless, there is again shown among Negroes as well as among whites the inverse association between illness and economic status or employment status. Perhaps the chief point of importance yielded by Figures 3 and 4 is the sensitiveness of illness rates to slight changes in income and employment status, even when all data are confined to neighborhoods which would be judged as “poor” by present-day housing standards. A survey of illness among Negro families in Central Harlem and white families in the Lower East Side districts of New York City was made by the Milbank Memorial Fund and the United States Public Health Service in the early spring of 1933. Both districts are areas of low average economic status and high mortality. The results indicated an excess of disabling illness among Negroes in the adult ages, but a lower illness rate for Negro children under 15 years of age than for white children. This relation was due to the lower incidence of certain epidemic diseases among the Negro children. The same inverse relation between the disabling illness rate and economic status was observed among Negroes as among whites, indicating the importance of such factors as standard of living and occupation in evaluating racial differences in morbidity and mortality rates. The marked excess in the mortality rate of urban Negroes compared with that of the white population (4) supports the a priori assumption of a proportionate excess in their illness rate. The results of previous studies of illness among Negroes in the general population have contributed somewhat inconclusive evidence of this relation due to limitation of scope of the investigations, or to paucity of the sample. In the National Health Survey conducted by the United States Public Health Service in 1935–1936,6 records of illness in a twelve-month period were obtained for approximately 230,000 Negroes. While the analysis of records for the entire surveyed group has not yet been completed, the results for a group of 30,652 Negroes and 140,263 white persons canvassed simultaneously in four large cities are of sufficient interest to justify their presentation in this preliminary report. The surveyed group comprises a sample taken from two Southern cities, Atlanta, Georgia, and Dallas, Texas; one Northern city, Newark, New Jersey; and one city of the East North Central section, Cincinnati, Ohio. A representative sample was obtained by an arbitrary division of the Census Enumeration districts into an average population of a sample of such being The distribution of the surveyed population in each city by is shown in Table with comparative figures for the total population as in the Census of as used in this survey also persons of other or The number of such persons is in each of these cities Dallas, in which the total of persons also one per cent The proportion of children under 15 years of age was somewhat and the proportion of persons years of age and over among the surveyed Negro population than the white Table The proportion of males in the Negro population was lower than in the white the of males to females being taken as being 80 for the Negro and for the white population of the four cities combined. The between the surveyed groups is found in their and economic status. Persons during the year the survey represented per cent of the Negro compared with 15 per cent for the The distribution of the surveyed population of the four cities by according to family income received in the year the survey date is shown in Table and the distribution for each city is in Table Negroes in surveyed families with an income of or per cent of the total Negro population while only per cent of the white population was in this income In the white 24 per cent of all persons were in families with an income of or Negroes in this income represented only 1 per cent of the The of this in economic level of the Negro and white surveyed of these four cities be in in the of the subsequent of their sickness In of this the data relate to Negro and white both of which represent samples of families taken from the poorer districts of the surveyed In the present section, are with samples of Negro and white which are, in representative of the total Negro and white population of the four surveyed cities, and in economic In the of the mortality rate is determined by the chronic diseases, which have the causes of On the other hand, the of the incidence rate of illness is determined by the acute diseases, of which are epidemic in in the incidence rate of illness for a year is therefore not it in part from in the prevalence of epidemic the effect of this however, the of certain of the illness rate for each city is not and be made of the relative of the rates for Negro and white surveyed groups according to and economic status. In the present therefore, the has been of showing the or of the of illness for cities, the of rates being presented only for the population of the four surveyed cities. On the of the which was made in the months between and the average prevalence rate of illness in the Negro population of the four surveyed cities was per cent, compared with a rate of per cent for the white population. rates are somewhat higher than those previously including in the present survey disabling gross not In the twelve-month period prior to the date of the illnesses disabling for or at a rate of per 1,000 population among Negroes, the rate for the white population being In the surveyed Negro group the rate, from the total of in a twelve-month period from illnesses of the previously over the total surveyed including the and the represented an average of of per for the white the comparable was found to be per The rate, or the average per case the survey was for the average case among Negroes, and 54 for the average case in the white population. In the Negro were for of disabling illness, the case rate for the white being The death rate in a twelve-month period for Negro persons surveyed was per 1,000 compared with a rate of for the white the rates for both groups being lower than death rates for the total population of these cities, a observed in the of The actual death rate in the total population of these four cities for the period to 1932 was for Negroes, and for the white population. In Table the of the Negro to the white rates for these of morbidity and mortality are presented for each surveyed city, and for the four cities combined. It will be observed that the and most excess in the rates for Negroes in the prevalence and the of which is determined largely by the chronic diseases. On the other hand, the excess for Negroes is and shows the for the disabling illness rate, and the of to disabling illnesses case both of which are by the high frequency of acute diseases. cities, it will be that these rates are consistently the the The excess observed in the prevalence rate of Negro compared with white persons of all ages is for by the higher rates of Negro Negro children under 15 years of age showing lower rates than white children. (Figure of prevalence rates for diseases classified as and on the of of Table that the low average rate of Negro children is due to the relatively low prevalence of acute diseases among the prevalence rates for the chronic diseases those of white children. The excessive death rates of Negroes in and early compared with the suggest that their lower average prevalence rates in this age period in part from of their of Disabling Illness by Age among Persons in Negro and White Families in Large Cities in the of as of the National Health Survey The of the age of the prevalence rate for the Negro and white surveyed groups of the four cities is by the prevalence of the rate at a age to the rate at all for each of the surveyed cities. (Figure In Newark, both Negro and white children under 15 years of age a higher proportion of those on the of the than in the three cities, due to the epidemic prevalence of measles during the period of the survey. While the prevalence rate for Negro children under 15 was lower than the rate for white children in each city (Table the excess in the white rate was notably in both and Newark, indicating the effect of the previously on children of both racial groups. In the disabling illness rate, the excess observed in the Negro rate for persons of all ages compared with the white arises from the excess in the rate for (Figure The in the disabling illness rate of white children, occurring in the age period to is not observed in the for Negro children, due to the lower frequency of the acute diseases among Negro on the other hand, the disabling illness rates for the chronic diseases among Negro children, while lower than the show a marked between the two Table The in the disabling illness rate of Negroes after 15 years of age is the period of to 24 in which the illness rate of the white population a is a period of a relatively high sickness rate for the The average disabling illness rate among Negroes at this age period in the four surveyed cities was 24 per cent higher than the rate for the white the excess being greater in the ages from 25 years. (Table Rate of Disabling Illness by Age among Persons in Negro and White Families in Large Cities in the of as of the National Health Survey Sex Variation The excess observed in the prevalence rate of illness among Negroes compared with the white population in the four surveyed cities is common to both the excess being somewhat higher for females (Table On the other hand, the disabling illness rate of Negro and white males was found to be approximately the the excess observed among Negroes of both compared with the white population being for by a higher disabling illness rate among Negro females, the rate exceeding the rate for white females by per cent. The disabling illness rates for all however, conceal the that both and female Negroes show a marked excess in disabling illness due to the chronic diseases Table compared with white persons of the same The in both prevalence and disabling illness rates was found to be for both Negro and white surveyed the rates for females exceeding that for males, a relation observed in illness in mortality rates. The of the prevalence rate for Negro females was compared with a of for white females, the rate being taken as The comparable for the disabling illness rates were for Negro females, and for white females. The in the disabling illness rate for Negroes is marked at ages 10 to 14 the excess for females at this age period being for largely by their higher rate for the chronic diseases. In the white the is not marked the age period to is Table The average of per and in an period is the of two the average per case of illness and the average number of of illness per in an period or disabling illness The excess observed in the rate of Negroes in the four cities for all causes of illness (Table thus from the that both their and frequency rates are higher than the comparable rates for the white population. We to a consideration of these rates by cause in broad groups in to the diseases which for the greater of illness among Negroes. Negroes of the adult ages (Table it is seen that the excess in the rate of Negroes from all causes of illness is the of the average and the higher frequency of of all disease the occurring among the acute diseases of the digestive in which the effect of a average per case is by a higher frequency of However, differences be observed in the to which the disease groups to the excess in the rate. The average of a case of chronic disease in the twelve-month period among Negro was 138 the the average Negro adult of chronic a frequency exceeding that of all other disease groups. The rate due to the chronic diseases therefore, at a to approximately for the average Negro white the chronic diseases showed the highest rate, but the of the rate for Negroes is due to the higher and frequency rates among Negroes for the chronic diseases. Negro children under 15 years of the of the average case of disabling illness from all causes was per cent higher than that of the average white However, the frequency of among Negro children was per cent lower than among white children, with the that the average Negro was approximately four in the twelve-month period, compared with a rate of for the average white Negro children, a lower frequency rate of disabling illness consistently in all disease groups. The frequency rate for the chronic diseases, however, is only lower than that for white children, and the excess observed in their rate from these causes to a somewhat higher rate for chronic disease among Negro children. and frequency rates for certain specific causes of illness are shown in Table by age in broad groups. It is that the average of per Negro adult due to respiratory tuberculosis is only higher than that for the average white due to the average per case of this disease among Negroes. interesting racial is observed between the rates for and acute digestive Negroes showing a lower rate for but a marked excess for other acute diseases of the digestive and frequency of Negro to white rates by cause in broad disease groups for persons of all ages are shown for each city in Table A marked excess in the rate for the chronic diseases among Negroes is observed in three of the four surveyed cities, the excess varying from per cent for Newark, to per cent for In Newark, the rate for the diseases among Negroes was only per cent and in Cincinnati, per cent higher than the white rate, indicating that in epidemic periods Negroes and whites show susceptibility to certain of the acute communicable Disabling illness rates for specific causes of illness for persons of all ages in the population of the four cities are shown in Figure Comparable rates for certain of these causes are shown in Table The excess observed in the disabling illness rate for among Negroes, and their lower rate for is of the the effect of the low economic status of the Negro on to The frequency rate for each of the acute communicable diseases of is found to be lower among Negroes in the of the four cities, the effect of the higher rates for diseases among Negroes in and being by the lower rates observed in and The excess in the Negro rate for is on a of the between which is not The excess observed in the Negro rates for the group of chronic diseases is seen to be due largely to the higher rates for the cardiovascular-renal diseases, rheumatism, and and the chronic diseases of the female of Negro and White Rate of Disabling Illness for Causes in Large Cities Surveyed in the of as of the National Health Survey In the of the four surveyed cities, it was found that the average Negro a of in the survey year than the average white this relation from the that the average of a case was and the number of frequent among Negroes than in the white population. the Negro and white groups have been shown to in average economic status, it is important to such as the to does a level of income increase the health and does the excess observed for certain of illness among Negroes persist among Negro and white groups of income Data for this report of the Negro and white surveyed groups by status only than which to some the of Negro and white the average income of the being The of illness specific for status indicate that Negroes in the population of the cities in fact, show a of the same general as the whites, the disabling illness rate, the rate, and the rate being higher in the than in the groups of both (Table When the of illness are compared for Negro and white groups on the excess observed in the disabling illness rate of Negroes of all income disappears, the rate being per cent lower than the rate for the white population. The excess in the rate for Negroes but is in an excess of per cent being observed in the rate of Negroes of all income the excess being 10 per cent for Negroes, compared with whites, on the of Negro to white rates for the groups of cities, it is of interest that in and the rates of Negroes on were somewhat lower than those for the whites of status. when the from differences in economic level is in the of the two racial groups in these surveyed cities, it is found that differences in standard of living in part for the higher rate of Negroes. The broad be drawn from a of Negro and white illness rates in a sample population of 30,652 Negroes and 140,263 white persons in four large cities canvassed in the National Health Survey made during In the twelve-month survey period, the of per due to illnesses which for a or was per cent higher in the Negro than in the white population. The higher rate for Negroes is due to the chronic diseases, which the average Negro eight per compared with for the average white Negro children under 15 years of the frequency of disabling illness was lower than among white children, due to the average lower incidence of and acute respiratory diseases among Negro children. However, Negro children to certain acute communicable diseases in epidemic in two of the surveyed cities showed disabling illness rates those for white children. consistently higher disabling illness rates for Negroes were observed for all disease groups. specific causes of illness, was found to be twice as frequent among Negroes as among and Negro rates for certain chronic cardiovascular-renal rheumatism, and notably higher than the The in standard of living which is with a income the health status of the Negro as by the of illness, the average Negro in the only as much per year as the average Negro on economic status, than racial in the to thus appears to in large for the higher rate observed among Negroes. From this it that the health of Negroes are than those of the average white population represent in the a as in the white by number in the higher income Table Table Table Table

Epidemiology has seen many theoretical advances over the past 20 years. Since the advances of one period often become the impediments of the next, it is timely to seek out disorders of thought that may beset our studies of disorders of health. In this undertaking, I speak as a premodern epidemiologist who has bent effort to promoting one kind of modern epidemiology. My intention is not to decry but to look forward. For epidemiology that is still to be, therefore, I shall venture some value-laden hopes. Premodem epidemiology was primarily an epidemiology of substance. It was epidemiology for problem solving and for the prevention or control of disease, subservient to this purpose and hence to its subject matter. At the same time, it was often epidemiology pursued intuitively, an avocation (excepting infectious disease epidemiologists) of gifted amateurs using primitive means. It engendered the excitement of the unexplored, and the frustration of technical incapacity. This kind of epidemiology was in decline by the 1950s and passe by, say, the early 1970s. Present day epidemiology, on the other hand, is primarily an epidemiology of technique, at risk of existing for its own sake regardless of subject matter. It is epidemiology pursued as a vocation by accomplished professionals who deploy refined and complex methods. In the absence of a central concern with subject matter, the satisfactions of technical command are held within narrow bounds; in the absence of broader purpose, an arsenal of methods might not necessarily be directed to the benefit of the public health. The transition from premodern to modern epidemiology was governed first by the historical shift in the substance of epidemiological studies from acute infectious diseases to chronic non-infectious diseases.

Much of the intellectual tradition of modern epidemiology stems from efforts to understand and combat chronic diseases persisting through the 20th century epidemiologic transition of countries such as the United States and United Kingdom. After decades of relative obscurity, infectious disease epidemiology has undergone an intellectual rebirth in recent years amid increasing recognition of the threat posed by both new and familiar pathogens. Here, we review the emerging coalescence of infectious disease epidemiology around a core set of study designs and statistical methods bearing little resemblance to the chronic disease epidemiology toolkit. We offer our outlook on challenges and opportunities facing the field, including the integration of novel molecular and digital information sources into disease surveillance, the assimilation of such data into models of pathogen spread, and the increasing contribution of models to public health practice. We next consider emerging paradigms in causal inference for infectious diseases, ranging from approaches to evaluating vaccines and antimicrobial therapies to the task of ascribing clinical syndromes to etiologic microorganisms, an age-old problem transformed by our increasing ability to characterize human-associated microbiota. These areas represent an increasingly important component of epidemiology training programs for future generations of researchers and practitioners.

In 1981, a profound crisis of authority was transforming the American health polity. Changing priorities between infectious and chronic diseases, communal and individual responsibilities for health, and comprehensive services and cost control created a fragmented health polity, leaderless and ill-equipped to address the AIDS epidemic. The American health polity may best serve the public interest when institutions within it do not accept fragmentation as the goal and the norm of health affairs.

In an increasingly globalized world, rapid population mobility and migration is reducing the differences in infectious disease epidemiology between regions of the world. The movement and relocation of populations between locations where the prevalence and incidence of infections are markedly different poses current and future challenges to those involved in clinical infectious diseases and public health program management. Historically, international attention has focused on the screening and treatment of acute infections of epidemic potential, but, as immigration significantly changes the demography of many nations, chronic infections will require increased attention. In countries with large mobile populations, the population-based burden of infections with long latency periods or significant noninfectious sequelae will make up an increasing amount of the infectious disease caseload and will require more-modern approaches than the traditional screening of arrivals. The globalization of chronic infectious disease epidemiology will require corresponding development of integrated programs to anticipate and manage these diseases in response to an increasingly mobile patient population.

Assessments of future threats posed by infection have focused largely on zoonotic, acute disease, under the rubric “emerging diseases.” Evolutionary and epidemiological studies indicate, however, that particular aspects of infrastructure, such as protected water supplies, vector‐proof housing, and health care facilities, protect against the emergence of zoonotic, acute infectious diseases. While attention in the global health community has focused on emerging diseases, there has been a concurrent, growing recognition that important chronic diseases, such as cancer, are often caused by infectious agents that are already widespread in human populations. For economically prosperous countries, the immediacy of this threat contrasts with their infrastructural protection from severe acute infectious disease. This reasoning leads to the conclusion that chronic infectious diseases pose a more significant threat to economically prosperous countries than zoonotic, acute infectious diseases. Research efforts directed at threats posed by infection may therefore be more effective overall if increased efforts are directed toward understanding and preventing infectious causes of chronic diseases across the spectrum of economic prosperity, as well as toward specific infrastructural improvements in less prosperous countries to protect against virulent, acute infectious diseases.

Chronic infectious diseases such as HIV, HBV, and HCV, among others, cause severe morbidity and mortality globally. Progressive decline in CD8 functionality, survival, and proliferative potential-a phenomenon referred to as CD8 exhaustion-is believed to be responsible for poor pathogen control in chronic infectious diseases. While the role of negative inhibitory receptors such as PD-1 in augmenting CD8 exhaustion has been extensively studied, the role of positive costimulatory receptors remains poorly understood. In this review, we discuss how one such costimulatory pathway, CD40-CD40L, regulates CD8 dysfunction and rescue. While the significance of this pathway has been extensively investigated in models of autoimmunity, acute infectious diseases, and tumor models, the role played by CD40-CD40L in regulating CD8 exhaustion in chronic infectious diseases is just beginning to be understood. Considering that monotherapy with blocking antibodies targeting inhibitory PD-1-PD-L1 pathway is only partially effective at ameliorating CD8 exhaustion and that humanized CD40 agonist antibodies are currently available, a better understanding of the role of the CD40-CD40L pathway in chronic infectious diseases will pave the way for the development of more robust immunotherapeutic and prophylactic vaccination strategies.

The research initiative CLINF addresses a central issue in planning for the responsible development of the North: an understanding of the impact of climate change on the geographic distribution and epidemiology of climate sensitive infectious diseases (CSIs), and their associated consequences for Arctic health, economic growth, and societal prosperity. Changes in infectious diseases transmission patterns are a likely consequence of changing climates, a neglected problem that is likely to have a profound effect on northern societies, including indigenous cultures. There is an urgent need to learn more about the complex underlying dynamic relationships, and apply this information to the prediction of future CSI impacts, using more complete, better validated, and integrated data and models. This chapter provides an overview of the thoughts behind the CLINF NCoE (Nordic Centre of Excellence), and the integrative context expressed therein. The most recent findings regarding climate change in the Arctic, as published by IPCC and other global networks, are presented. In the international CLINF consortium of researchers, nine human and 18 animal husbandry diseases have been selected for study due to their potential for being climate sensitive. The human infections were selected by an international consortium of researchers, to represent fundamentally different transmission processes. The main CLINF objectives are the construction of practical tools for the decision-makers who are responsible for the development of northern societies. By contributing to the development of an early warning system for increased risks for CSIs to spread at the local level effective policy responses may be formulated. The overall aim of CLINF is to support the sustainability of Arctic development.

Acute and chronic diseases as part of multimorbidity in acutely hospitalized older patients

World Lung Day: what, why, and where to?