Meteorologic influences on Plasmodium falciparum malaria in the highland tea estates of Kericho, Western Kenya.Recent epidemics of Plasmodium falciparum Plasmodium fal·cip·a·rum n. A protozoan that causes falciparum malaria. malaria have been observed in high-altitude areas of East Africa. Increased malaria incidence in these areas of unstable malaria transmission has been attributed to a variety of changes including global warming global warming, the gradual increase of the temperature of the earth's lower atmosphere as a result of the increase in greenhouse gases since the Industrial Revolution. . To determine whether the reemergence of malaria in western Kenya could be attributed to changes in meteorologic me·te·or·ol·o·gy n. The science that deals with the phenomena of the atmosphere, especially weather and weather conditions. [French météorologie, from Greek conditions, we tested for trends in a continuous 30-year monthly malaria incidence dataset (1966-1995) obtained from complete hospital registers at a Kenyan tea plantation. Contemporary monthly meteorologic data (1966-1995) that originated from the tea estate meteorologic station and from global climatology climatology Branch of atmospheric science concerned with describing climate and analyzing the causes and practical consequences of climatic differences and changes. Climatology treats the same atmospheric processes as meteorology, but it also seeks to identify slower-acting records were also tested for trends. We found that total hospital admissions (malaria and nonmalaria) remained unchanged while malaria admissions increased significantly during the period. We also found that all meteorologic variables showed no trends for significance, even when combined into a monthly suitability index for malaria transmission. We conclude that climate changes have not caused the highland malaria resurgence in western Kenya. ********** Highland malaria has returned to the tea estates of western Kenya after an absence of nearly 30 years (1-3). Altitude and weather influence malaria epidemiology in highland areas because of the slowing of parasite development within the anopheline anopheline pertaining to the anopheles genus of mosquitoes. vectors at lower temperatures (4). Increased malaria incidence in unstable transmission areas has been variously attributed to changes in land-use patterns (5); population migration (6,7); changes in mosquito vector populations (8); breakdown in provision of health services health services Managed care The benefits covered under a health contract (9), especially insecticide spraying (10,11); drug resistance (12-16); and meteorologic changes (17,18), particularly global warming (19-25). We investigated whether climate changes could be implicated im·pli·cate tr.v. im·pli·cat·ed, im·pli·cat·ing, im·pli·cates 1. To involve or connect intimately or incriminatingly: evidence that implicates others in the plot. 2. in the reemergence of malaria in a unique 30-year malaria and meteorologic time series, collected from the health-care system on a tea plantation in the western highlands Western Highlands may refer to:
Methods Study Site and Clinical Data Long-term malaria illness and total hospital admissions data (January 1966-December 1995) exist from a large tea plantation in Kericho, Kenya, which is operated by Brooke Bond Brooke Bond was a brand-name tea retailer in the United Kingdom. Brooke Bond & Company was founded by Arthur Brooke who was born at 6 George Street, Ashton under Lyne, Lancashire, England in 1845. He opened his first Tea Shop in Manchester, Lancashire. Kenya Ltd. (3,31,32). The plantation, located in the western Riff Valley highlands, covers an area of approximately 141 [km.sup.2] and ranges from 1,780 to 2,225 m above mean sea level. Epidemic malaria was first recorded on the Kericho tea estates during World War II and was eventually controlled by a combination of mass administration of proguanil Proguanil (proguanil hydrochloride) is a prophylactic antimalarial drug, which works by stopping the malaria parasite, Plasmodium falciparum and Plasmodium vivax, from reproducing once it is in the red blood cells. and residual insecticide spraying during the late 1940s (2). Currently, the Brooke Bond Kenya Ltd. plantation consists of approximately 20 separate tea estates with a total of 50,000 employees and dependents, who receive their medical care from the company-operated health systems. The company hospital maintains a 24-hour, 7-day clinical admission service for patients who need intensive clinical management. Stained blood smears from patients with suspected malaria are examined; this procedure, in combination with further supportive clinical and laboratory procedures, is used to confirm a primary malaria diagnosis. Case numbers in Kericho can be treated as incidence figures since the population eligible for health care remained at approximately 50,000 during the recording period (32). No centralized preventive chemoprophylaxis chemoprophylaxis /che·mo·pro·phy·lax·is/ (-pro?fi-lak´sis) prevention of disease by means of a chemotherapeutic agent. che·mo·pro·phy·lax·is n. Disease prevention by use of chemicals or drugs. , vector control Vector control is any method to limit or eradicate the vectors of vector born diseases, for which the pathogen (e.g. virusor parasite) is transmitted by a vector which can be mammals, birds or arthropods, especially insects, and more specifically mosquitoes. , or bed-net distribution has been implemented since the late 1950s. A substantial minority of the tea estate workers originate from the holoendemic Lake Victoria area and travel back and forth intermittently to their home areas; however, this travel pattern has been occurring since the road was surfaced in the 1950s and has not changed recently. This study was conducted under a protocol approved by the Kenyan National Ethical Review Committee (SSC SSC Secondary School Certificate SSC Standard Systems Center (USAF) SSC State Services Commission (New Zealand) SSC Swedish Space Corporation SSC Salem State College (Massachusetts) 484) and the U.S. Army Office of the Surgeon General The U.S. Surgeon General is charged with the protection and advancement of health in the United States. Since the 1960s the surgeon general has become a highly visible federal public health official, speaking out against known health risks such as tobacco use, and promoting disease (WRAIR WRAIR Walter Reed Army Institute of Research 682). Meteorologic Data Two meteorologic datasets were compiled. Point locality measurements of mean monthly temperature ([degrees]C) and monthly total rainfall (mm) were obtained from the Tea Research Foundation meteorologic station on the Kericho tea estates for the 1966-1995 period. Climate data were also obtained from a global 0.5 x 0.5[degrees] (approximately 55 x 55 km [3,025 [km.sup.2]] at the equator) gridded dataset of monthly terrestrial surface climate for the 1966-1995 period (33,34) (available from: URL URL in full Uniform Resource Locator Address of a resource on the Internet. The resource can be any type of file stored on a server, such as a Web page, a text file, a graphics file, or an application program. : http:/ /www.cru cru n. pl. crus 1. A vineyard or wine-producing region in France. 2. A grade or class of wine: premier cru. .uea.ac.uk/link). The dataset was used to ensure that results from the single meteorologic station were in agreement with data from a wider geographic area; this procedure also allowed a wider range of climate variables, including temperature extremes, to be tested. Primary variables of precipitation (mm), mean temperature ([degrees]C), and diurnal diurnal /di·ur·nal/ (di-er´nal) pertaining to or occurring during the daytime, or period of light. di·ur·nal adj. 1. Having a 24-hour period or cycle; daily. 2. temperature range ([degrees]C) were available and interpolated interpolated /in·ter·po·lat·ed/ (in-ter´po-la?ted) inserted between other elements or parts. from extensive meteorologic station data by using angular distance-weighted averaging of anomaly fields. The secondary variable of vapor pressure vapor pressure, pressure exerted by a vapor that is in equilibrium with its liquid. A liquid standing in a sealed beaker is actually a dynamic system: some molecules of the liquid are evaporating to form vapor and some molecules of vapor are condensing to form liquid. was also provided, interpolated where available, and calculated from primary variables, when the coverage of meteorologic stations was insufficient. Minimum and maximum monthly temperature estimates were created by subtracting or adding, respectively, half the diurnal temperature range from mean monthly temperature. Time series were derived by using an extraction routine developed in ENVI (Research Systems Inc., Boulder, CO) with georeferencing information for Kericho (0.33[degrees]S, 35.37[degrees]E), obtained from Encarta (Microsoft, Seattle, WA). To investigate whether a combination of meteorologic conditions was changing and thus facilitating the resurgence of malaria, we also categorized months as suitable for Plasmodium falciparum transmission if they had a mean monthly temperature exceeding 15[degrees]C (since temperatures experienced by the indoor resting Anopheles gambiae Anopheles gambiae, refers to a complex of morphologically indistinguishable mosquitoes in the genus Anopheles, which contains the most important vectors of malaria in Sub-Saharan Africa [1], and the most efficient malaria vectors in the world. vectors are likely to be 3[degrees]C-5[degrees]C higher) and monthly rainfall totals exceeding 152 mm (1,4) by using the gridded climatology data. The numbers of suitable months for transmission were summed, totaled for each year, and tested for the 1966-1995 period. Statistical Analyses To test for trends in the climate and malaria suitability time series, we estimated the following regression equation Regression equation An equation that describes the average relationship between a dependent variable and a set of explanatory variables. : [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII ASCII or American Standard Code for Information Interchange, a set of codes used to represent letters, numbers, a few symbols, and control characters. Originally designed for teletype operations, it has found wide application in computers. ] where y is the variable of interest; [alpha], [beta], ,[gamma] and [[mu].sub.j]`s are regression parameters; [[epsilon].sub.t] is a normally distributed error term with mean zero; and t is a deterministic time trend. The centered dummy variables [d.sub.j] model the monthly seasonal variations in climate. The coefficients [[mu].sub.j] sum to zero. [DELTA] is the first difference operator. The lagged values of the dependent variable model the serial correlation serial correlation The relationship that one event has to a series of past events. In technical analysis, serial correlation is used to test whether various chart formations are useful in projecting a security's future price movements. in the dependent variable. We chose the number of lags, p, using the adjusted R-square statistic. The maximal number of lags p considered was 24. If the time series y can be characterized as the sum of a stationary stochastic process Noun 1. stationary stochastic process - a stochastic process in which the distribution of the random variables is the same for any value of the variable parameter and a linear time trend, then the appropriate test for the trend is a t test on [beta] in (1). If the series is a random walk, however, or a more complex stochastically trending process, the critical levels for the distribution of the t score in this regression are much greater than usual (35), and alternative tests should be employed. Since many climate time series contain a stochastically trending component (36), the nature of the series must be explored before testing for climate change. This methodology issue complicates the evaluation of the significance of trends established with standard regression procedures often used in such studies. If [gamma]=0 (a unit root in the autoregressive process) and [beta]=0, then y is a random walk. The random walk may also have a deterministic drift term ([alpha][not equal to]0). In either case, however, the series is nonstationary, and classical regression inference does not apply. The nonstandard non·stan·dard adj. 1. Varying from or not adhering to the standard: nonstandard lengths of board. 2. distributions of [alpha], [beta], and [gamma] have been tabulated by Dickey and Fuller (37,38). We first tested for the presence of a unit root by evaluating the t statistic t statistic, t distribution the statistical distribution of the ratio of the sample mean to its sample standard deviation for a normal random variable with zero mean. for [alpha] against its nonstandard distribution. The critical value for this so-called Augmented Dickey-Fuller at the 5% level is -3.45. Values of the t statistic for y more negative than this critical value indicate that the series is not a random walk and vice versa VICE VERSA. On the contrary; on opposite sides. . If the null hypothesis null hypothesis, n theoretical assumption that a given therapy will have results not statistically different from another treatment. null hypothesis, n is rejected, then the t statistics associated with [alpha] and [beta] are normally distributed. If the unit root hypothesis is accepted, then these statistics also have nonstandard distributions. The correct test for a trend is then the t test on a in (1) with the omission of the linear trend. The test's critical value at the 5% significance level is 2.54. The results of these tests are presented in the Table. We also regressed temperature and rainfall data from the meteorologic station at Kericho on the same variables from the interpolated climatology (33,34) by using a variety of formulations including levels, logarithms, and a regression adjusted for heteroscedasticity. We then tested whether the slope coefficients were significantly different from unity, which should not be the case if the gridded dataset is a good proxy for the climate at Kericho. Results During the period 1966-1995, malaria incidence increased significantly (p=0.0133) while total (i.e., malarial and other) admissions to the tea estate hospital showed no significant change (Table and Figure 1a,b), Measurements of mean monthly temperature and total monthly rainfall also showed no significant changes (Table and Figure 1c,d). Similar results were shown by the climatology data interpolated from a wider area. Mean, maximum, and minimum monthly temperatures; precipitation; and vapor pressure all demonstrated no significant trends (Table; Figure 2a,b,c). Moreover, the interpolated climatology data, when transformed into month of malaria transmission suitability (1,4), again showed no significant changes (Table; and Figure 2d). [FIGURES 1-2 OMITTED] Results were very similar, though significance levels varied, between the three formulations of the regression model that compared the local meteorologic station data and those from the interpolated climatology data (33,34). The coefficient for the regression of the meteorologic station rainfall data on the interpolated climatology precipitation data is in every case not significantly different from unity. Significance levels are 10% for the model in levels, 18% for the heteroscedasticity-adjusted model, and 96% for the logarithmic logarithmic pertaining to logarithm. logarithmic relationship when the logs of two variables plotted against each other create a straight line. model. In the regression of the two temperature series, however, the coefficient is significantly different from unity in every case, as is a joint test statistic for the two slope coefficients. Discussion The resurgence of P falciparum malaria fal·cip·a·rum malaria n. Malaria caused by Plasmodium falciparum and characterized by severe malarial paroxysms that recur about every 48 hours and often by acute cerebral, renal, or gastrointestinal manifestations. in the East African highlands (3,8,18,26, 40-44) has led several researchers to speculate that climate change is a predominant cause (23,45-50). On the basis of these studies, which have been disputed by experts in vector-borne disease vector-borne disease Infectious diseases Any infection, usually transmitted by insects–eg, ticks–eg, Lyme disease, Rocky Mountain spotted fever, ehrlichiosis, Colorado tick fever; mosquitos–eg, California-or La Crosse, St Louis, Eastern, Western biology (10,27-29, 51,52), and some biological modeling, which has been robustly criticized (53), the International Panel on Climate Change has recently concluded with "medium-to-high confidence" that there will be a net increase in the range and incidence of malaria (49); the results of our work do not support these conclusions. Malaria incidence increased significantly (p=0.0133) during the 1966-1995 period, while total admissions remained unchanged. Besides an increase in local malaria transmission, two other factors may have influenced the increase in malaria hospitalizations. An increase in malaria severity indicated by an increased case-fatality rate (from 1.3% in the 1960s to 6% in the 1990s) is most likely linked to chloroquine chloroquine /chlo·ro·quine/ (klor´o-kwin) an antiamebic and anti-inflammatory used in the treatment of malaria, giardiasis, extraintestinal amebiasis, lupus erythematosus, and rheumatoid arthritis; used also as the hydrochloride and resistance, which we believe to be the probable cause Apparent facts discovered through logical inquiry that would lead a reasonably intelligent and prudent person to believe that an accused person has committed a crime, thereby warranting his or her prosecution, or that a Cause of Action has accrued, justifying a civil lawsuit. of much of the overall increase in malaria transmission (32). Travel to and from the Lake Victoria region by a minority of the tea estate workers also exerts an upward influence on malaria transmission in Kericho since such travel increases the numbers of workers asymptomatically carrying gametocytes, which infect mosquitoes for further human infection. This complex topic is the subject of a future publication. All climate variables, whether from the Kericho tea estate meteorologic station or the pixel covering Kericho in the global climatology dataset showed no significant trends, despite the fact that equivalence tests showed some significant differences between the temperature time series--findings that are in agreement with a broader geographic analysis of East African data from 1911 to 1995 (26) and lend support to the appropriateness of interpolated climate data for use in these investigations. We also think that, when examining trends in meteorologic phenomena, epidemiologists should use more robust statistical techniques for the reasons outlined in the methods. The results of this detailed examination of coincident empirical data do not support the widespread, recent speculation regarding malaria resurgences in response to climate change. No aspect of climate has changed significantly--neither the temperature extremes (maximum and minimum) nor the periods when meteorologic data were transformed into months when malaria transmission is possible. Further study has also shown that variability in these meteorologic variables, independent of any longer term trends, has decreased (54). We must therefore look elsewhere for the causes of these resurgences (27,28,32). These factors are likely to vary. In Kericho, however, increased chloroquine resistance has been strongly argued to be the cause, since all other relevant environmental and sociologic factors are unchanged (32). The attraction of the global warming hypothesis as an explanation of highland malaria is the existence of a continental trend toward global warming coincident with a trend toward increasing malaria incidence in several parts of Africa, ranging from Senegal (13,14) to Madagascar (10). Where such malaria increases have been examined in detail, however, alternative explanations such as discontinuation dis·con·tin·u·a·tion n. A cessation; a discontinuance. Noun 1. discontinuation - the act of discontinuing or breaking off; an interruption (temporary or permanent) discontinuance of anti-vector measures in Madagascar (10) or chloroquine resistance in Senegal appear to be more likely causes (13,14). Malaria epidemiology is greatly influenced by a range of local factors, making a consistent continent-wide explanation seem unlikely (28,52). We do not argue that meteorologic conditions have no immediate impact on the seasonal dynamics and incidence of malaria or that climate change is probably not an important future concern in public health. Rather we urge some caution in the interpretation of synonymous changes in climate over wider areas and local changes in malaria incidence.
Table. Trend of malaria, climate, and malaria suitability variables,
Kericho tea estates, 1966-1995 (a,b)
Variable p ADF (c) b t
Malaria incidence 5 -4.00 0.0238 2.49
Total admissions 6 -2.76 -0.0069 -0.28
Tmean met. stat. ([degrees]C) 8 -3.41 0.0004 1.76
Rain met. stat. (mm) 1 -11.91 -0.0202 -0.52
Tmean clim. ([degrees]C) 1 -7.51 0.0035 1.60
Tmax clim. ([degrees]C) 24 -4.66 0.0070 1.68
Tmin clim. ([degrees]C) 1 -8.36 0.0038 1.55
Precipitation clim. (mm) 1 -11.70 -0.0098 -0.36
Vapor pressure clim. (hPa) 1 -8.37 0.0038 1.66
Garnham suitability (mo) (d) 4 -4.21 -0.0380 -0.89
Variable p ta Q Sig. Q
value (c)
Malaria incidence 0.0133 0.1801 58.7394 0.0097
Total admissions 0.7820 -0.4151 30.9302 0.7083
Tmean met. stat. ([degrees]C) 0.0799 -0.0211 40.8630 0.2653
Rain met. stat. (mm) 0.6066 -0.0074 43.3753 0.1858
Tmean clim. ([degrees]C) 0.1103 -0.0980 46.6888 0.1094
Tmax clim. ([degrees]C) 0.0935 0.0592 22.6634 0.9592
Tmin clim. ([degrees]C) 0.1233 -0.1944 45.1424 0.1412
Precipitation clim. (mm) 0.7205 -0.0745 34.2984 0.5497
Vapor pressure clim. (hPa) 0.0974 -0.1829 45.5674 0.1318
Garnham suitability (mo) (d) 0.3850 -0.4488 5.6658 0.7729
(a) Tmean, the mean monthly temperature; Tmax, the mean of maximum
monthly temperatures; Tmin, the mean of minimum monthly temperatures;
met. stat., meteorologic station data from the Kericho tea estate;
clim., data derived from the global gridded climatology
dataset (33,34).
(b) Figures in bold denote significance at the 5% level. p is the
number of lagged differenced dependent variables selected.
(c) ADF, the Augmented Dickey-Fuller t-test for [gamma]=0. The 5%
critical value is -3.45. Exact p values are not available for ADF and
[tau][alpha] statistics. The distribution of the t statistic for the
slope parameter [beta] has the standard t distribution under the
assumption that [gamma]<0. [tau][alpha] is the t statistic for the
intercept term in the autoregression without a linear time trend. This
test is the appropriate one for a trend if [gamma]=0. Its 5% critical
value is 2.54. The Q statistic is a portmanteau test for general serial
correlation and is distributed as chi square (39).
(d) Garnham suitability (1,4) refers to the number of months with a
mean monthly temperature exceeding 15[degrees]C and monthly rainfall
totals exceeding 152 mm (when the gridded climatology data are used).
These data are therefore annual data, whereas all other time-series are
monthly observations.
Acknowledgments The authors acknowledge the management and staff of Brooke Bond Kenya Ltd. and its Central Hospital in Kericho, whose outstanding medical system made this study possible, and the support of the Kenya Medical Research Institute The Kenya Medical Research Institute (KEMRI) is one of East Africa's leading medical research centres. It is located in Kenya's capital, Nairobi. Established in 1979, KEMRI has played an important role in the fight against malaria, HIV/AIDS and other diseases in Kenya, and in Nairobi, Kenya. We also thank Wilson K. Ngetich for supplying the local meteorologic data. SIH SIH Système d'Information Hospitalier SIH Syndicat Interhospitalier (French: union of hospitals) is currently supported as an advanced training fellow by the Wellcome Trust (#056642). RWS RWS Rijkswaterstaat RWS Running with Scissors RWS IEEE Radio and Wireless Symposium RWS Romano-Ward Syndrome RWS Remote Weapon Station (US Army) RWS Remote Winsock RWS Range While Search RWS Radar Warning System is a senior Wellcome Trust fellow (#033340). References (1.) Garnham PCC PCC prothrombin complex concentrate. . Malaria epidemics at exceptionally high altitudes in Kenya. BMJ BMJ n abbr (= British Medical Journal) → vom BMA herausgegebene Zeitschrift 1945;11:45-7. (2.) Strangeways-Dixon D. Paludrine (proguanil) as a malarial prophylactic amongst African labour in Kenya. East Aft Med J 1950;27:127-30. (3.) Malakooti MA, Biomndo K, Shanks GD. Reemergence of epidemic malaria in the highlands of western Kenya. Emerg Infect Dis 1998;4:671-6. (4.) Garnham PCC. The incidence of malaria at high altitudes. Journal of the National Malaria Society 1948;7:275-84. (5.) Lindblade KA, Walker ED, Onapa AW, Katungu J, Wilson ML. Land use change alters malaria transmission parameters by modifying temperature in a highland area of Uganda. Trop Med Int Health 2000;5:263-74. (6.) Van der Stuyft P, Manirankunda L, Delacollette C. L'approche de risque ris·qué adj. Suggestive of or bordering on indelicacy or impropriety. [French, from past participle of risquer, to risk, from risque, risk; see risk.] Adj. dans le diagnostic du paludisme-maladie en regions d'altitude. Annales de la Societe Beige de Medecine Tropicale 1993;73:81-9. (7.) Bashford G, Richens J. Travel to the coast by highlanders and its implications for malaria control. Papua New Guinea Papua New Guinea (păp`  ə, –y Medical Journal
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The warmth and humidity of the tropics and the often unsanitary conditions under which so many people in those areas live contribute to the development and . London:University of London For most practical purposes, ranging from admission of students to negotiating funding from the government, the 19 constituent colleges are treated as individual universities. Within the university federation they are known as Recognised Bodies ; 1996. (44.) Kilian AHD AHD Ahead AHD American Heritage Dictionary AHD Australian Height Datum AHD Arrowhead AHD Airhead AHD Academic Honors Diploma AHD Alveolar Hydatid Disease AHD Advanced Help Desk AHD Atherosclerotic Heart Disease , Langi P, Talisuna A, Kabagambe G. Rainfall pattern, El Nino and malaria in Uganda. Trans R Soc Trop Med Hyg 1999;93:22-3. (45.) Epstein PR, Diaz HF, Elias S, Grabherr G, Graham NE, Martens WJM, et al. Biological and physical signs of climate change: focus on mosquito-borne diseases. Bulletin of the American Meteorological Society Bulletin of the American Meteorological Society is a publication of the American Meteorological Society. The official organ of the society, devoted to editorials, topical reports to members, articles, professional and membership news, conference announcements, programs and 1998;79:409-17. (46.) Martens P. How will climate change affect human health? American Scientist 1999;87:534-41. (47.) Patz JA, Lindsay SW. New challenges, new tools: the impact of climate change on infectious diseases. Curr Opin Microbiol 1999;2:445-51. (48.) Bonora S, De Rosa FG, Boffito M, Di Perri C4 Rossati A. Rising temperature and the malaria epidemic in Burundi. Trends Parasitol 2001;17:572-3. (49.) McCarthy JJ, Canziani OF, Leary NA, Dokken DJ, White KS. Climate change 2001: impacts, adaptation, and vulnerability--contribution of Working Group II to the Third Assessment Report of the Intergovernmental Panel on Climate Change “IPCC” redirects here. For other uses, see IPCC (disambiguation). The Intergovernmental Panel on Climate Change (IPCC) was established in 1988 by two United Nations organizations, the World Meteorological Organization (WMO) and the United Nations Environment . Cambridge: Cambridge Univ. Press; 2001. (50.) Patz JA, Reisen WK. Immunology, climate change and vector-borne diseases. Trends Immunol 2001;22:171-2. (51.) Reiter P. Global-warming and vector-borne disease in temperate regions and at high altitude. Lancet 1998;351:839. (52.) Reiter P. Climate change and mosquito-borne disease. Environ Health Perspect 2001;109:141-61. (53.) Rogers DJ, Randolph SE. The global spread of malaria in a future, warmer world. Science 2000;289:1763-6. (54.) Rogers DJ, Randolph SE, Snow RW, Hay SI. Satellite imagery in the study and forecast of malaria. Nature 2002;415:710-5. G. Dennis Shanks, * Simon I. Hay, [dagger][double dagger] David I. Stern, [section] Kimutai Biomndo, [paragraph] (1) Robert W. Snowl [dagger][double dagger] (1) Dr. Biomndo is deceased. * U.S. Army Medical Research Unit-Kenya, Nairobi, Kenya; [dagger] University of Oxford, Oxford, U.K.; [double dagger] Kenya Medical Research Institute/Wellcome Trust Collaborative Programme, Nairobi, Kenya; [section] Rensselaer Polytechnic Institute Rensselaer Polytechnic Institute, at Troy, N.Y.; coeducational; founded and opened 1824 as Rensselaer School; chartered 1826. It was called Rensselaer Institute from 1837 to 1861. , Troy, New York Troy is a city in New York, U.S., and the county seat of Rensselaer County. As of the 2000 census, the population was 49,170; in 1910, the population was 76,813. The city's motto is Ilium fuit, Troja est, which means "Troy was, Troy is. , USA; and [paragraph] Brooke Bond Central Hospital, Kericho, Kenya Col. G. Dennis Shanks is the former director of the U.S. Army Component of the Armed Forces Institute of Medical Research in Bangkok, Thailand, which is a part of the Walter Reed Army Institute of Research This article is about the U.S. Army medical research institute (not the hospital). Otherwise, see Walter Reed (disambiguation). The Walter Reed Army Institute of Research (WRAIR) is the largest biomedical research facility administered by the U.S. . He is a physician trained in pediatrics and tropical medicine whose main professional interests are malaria chemotherapy, malaria epidemiology, and clinical trials in developing countries. Address for correspondence: G. Dennis Shanks, Armed Forces Institute of the Medical Sciences, APO apo- 1 A prefix indicating a protein component in a conjugated molecule–eg, apoferritin, apolipoprotein, see there 2 Apolipoprotein, see there AP 96546 USA; fax: 66 2 2476030; e-mail: shanksdg@thai.amedd.army, mil; or Simon I. Hay, TALA Research Group, Department of Zoology zoology, branch of biology concerned with the study of animal life. From earliest times animals have been vitally important to man; cave art demonstrates the practical and mystical significance animals held for prehistoric man. , University of Oxford, South Parks Road South Parks Road is a road in Oxford, England. It runs east-west past the main Science Area of the University of Oxford, where many of the science departments are located. , Oxford OX1 3PS, U.K.; fax: 44 1865 271243; e-mail: simon.hay@zoology.ox.ac.uk |
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