Nutritional status, globulin titers, and parasitic infections of two populations of Tanzanian school children

Nutritional Status and Humoral Immune Response to Plasmodium falciparum in Children Aged 6-59 Months

Malaria is a leading cause of morbidity and mortality in Africa. Children are mostly exposed to this disease; numerous studies have investigated the relationship between child malnutrition and either malaria morbidity or infection. Few studies demonstrated the interaction between child malnutrition and specific anti-Plasmodium falciparum immune responses. The purpose of this study was to investigate the impact of nutritional status and iron on total anti-Plasmodium falciparum IgG levels in children living in the Gado-Badzéré refugee camp. We carried out a cross-sectional study during August–November 2017 in the Gado-Badzéré refugee camp in the East region of Cameroon. Children aged from 6 to 59 months with fever were recruited from the medical center. The data were recorded using a standardized data collection sheet and were analyzed using SPSS and WHO Anthro software. The total anti-Pf 3D7 total IgG level was determined using an ELISA technique while a colorimetric method was used to measure the total iron level. A total of 83 patients aged 6–59 months were enrolled in this study. The prevalence of malaria and malnutrition was 47% and 31%, respectively. Acute malnutrition was statistically less recurrent in noninfected children compared with that in the infected children. The infection tended to have significant influence on the level of anti-Plasmodium falciparum antibodies in children. In addition, nutritional status and serum iron levels had no significant influence on children's anti-Pf IgG T levels. Malaria and malnutrition remain real public health problems in the Gado-badzéré refugee camp. Knowledge of the nutritional profile of the population would be of great benefit in setting up an appropriate health program. We therefore suggest that more standardized studies be conducted to highlight the effect of nutrition and micronutrients on immunological status.

Female Nutritional Status across the Life-Span in Sub-Saharan Africa. 1. Prevalence Patterns

This article reviews and synthesizes existing nutritional studies that provide gender-disaggregated data from sub-Saharan Africa. The analytic focus is on female nutritional status across the life-span. However, it was found that available data are biased towards preschool children and women of reproductive age. As in other economically disadvantaged parts of the world, the two most prevalent nutritional deficiencies among females in sub-Saharan Africa are iron-deficiency anaemia and protein-energy malnutrition. In comparison with other regions of the world, sub-Saharan African females seem to be nutritionally better off than females in South Asia, but as malnourished as, or more malnourished than, females elsewhere. Indirect indicators of nutritional status, such as birthweight and maternal mortality, suggest that the nutritional situation of women in Western Africa is poorer than that of women in Eastern and Southern Africa. In comparison with males in sub-Saharan Africa, however, no consistent pattern of female nutritional disadvantage was found.

Is chronic malnutrition associated with an increase in malaria incidence? A cohort study in children aged under 5 years in rural Gambia

Background

Malnutrition is common in children in sub-Saharan Africa and is thought to increase the risk of infectious diseases, including malaria. The relationship between malnutrition and malaria was examined in a cohort of 6–59 month-old children in rural Gambia, in an area of seasonal malaria transmission. The study used data from a clinical trial in which a cohort of children was established and followed for clinical malaria during the 2011 transmission season. A cross-sectional survey to determine the prevalence of malaria and anaemia, and measure the height and weight of these children was carried out at the beginning and end of the transmission season. Standard anthropometric indices (stunting, wasting and underweight) were calculated using z-scores.

Results

At the beginning of the transmission season, 31.7% of children were stunted, 10.8% wasted and 24.8% underweight. Stunting was more common in Fula children than other ethnicities and in children from traditionally constructed houses compared to more modern houses. Stunted children and underweight children were significantly more likely to have mild or moderate anaemia. During the transmission season, 13.7% of children had at least one episode of clinical malaria. There was no association between stunting and malaria incidence (odds ratio = 0.79, 95% CI: 0.60–1.05). Malaria was not associated with differences in weight or height gain.

Conclusions

Chronic malnutrition remains a problem in rural Gambia, particularly among the poor and Fula ethnic group, but it was not associated with an increased risk of malaria.

Trial registration

Trial registration: ISRCTN, ISRCTN01738840, registered: 27/08/2010 (Retrospectively registered).

Elevated prevalence of malnutrition and malaria among school-aged children and adolescents in war-ravaged South Sudan

Emerging as a sovereign state from decades of civil war, the Republic of South Sudan now faces poverty, a lack of health care infrastructure, a high burden of infectious diseases and a widespread food insecurity. School-aged children and youth, in particular, represent a high-risk demographic for malnutrition and infectious diseases. We screened 109 school-aged children and youth for nutritional status and malaria antigenaemia in Akuak Rak, South Sudan, and found a large proportion of underweight (77/109 = 73%) and prevalent malaria (44/109 = 40%). There was no significant association between malnutrition and malaria. This study represents one of the few published reports on child and youth nutritional status and malaria prevalence in South Sudan since its independence. The implementation of nutrition and malaria screening combined with evidence-based interventions in schools could help target this high burden vulnerable group.

The association between nutritional status and malaria in children from a rural community in the Amazonian region: a longitudinal study

Background

The relationship between malaria and undernutrition is controversial and complex. Synergistic associations between malnutrition and malaria morbidity and mortality have been suggested, as well as undernutrition being protective against infection, while other studies found no association. We sought to evaluate the relationship between the number of malaria episodes and nutritional statuses in a cohort of children below 15 years of age living in a rural community in the Brazilian Amazon.

Methodology/Principal Findings

Following a baseline survey of clinical, malaria and nutritional assessment including anthropometry measurements and hemoglobin concentration, 202 children ranging from 1 month to 14 years of age were followed for one year through passive case detection for malaria episodes. After follow-up, all children were assessed again in order to detect changes in nutritional indicators associated with malaria infection. We also examined the risk of presenting malaria episodes during follow-up according to presence of stunting at baseline. Children who suffered malaria episodes during follow-up presented worse anthropometric parameters values during this period. The main change was a reduction of the linear growth velocity, associated with both the number of episodes and how close the last or only malaria episode and the second anthropometric assessment were. Changes were also observed for indices associated with chronic changes, such as weight-for-age and BMI-for-age, which conversely, were more frequently observed in children with the last or only episode occurring between 6 and 12 months preceding the second nutritional assessment survey. Children with inadequate height-for-age at baseline (Z-score < -2) presented lower risk of suffering malaria episodes during follow-up as assessed by both the log-rank test (p =0.057) and the multivariable Cox-proportional hazards regression (Hazard Ratio = 0.31, 95%CI [0.10; 0.99] p=0.049).

Conclusions

Malaria was associated with impaired nutritional status amongst children in an endemic area of the Western Brazilian Amazon where P. vivax predominates. Our data all supports that the association presents differential effects for each age group, suggesting distinct pathophysiology pathways. We were also able to demonstrate that undernourishment at baseline was protective to malaria during follow-up. These findings support an intriguing interaction between these conditions in the rural Amazon and the need for a more integrative approach by health systems in endemic areas.

Malaria is one of the most serious public health problems in the world, with 3.3 billion people at risk of contracting the disease and almost one million deaths annually, primarily in children younger than five years of age. Undernutrition is also a morbidity of importance to the public worldwide and primarily affects children in tropical regions. In the present study, we sought to analyze the relationship between malaria and undernutrition in children living in a rural Amazonian community where malaria is endemic. Children from 1 month to 14 years of age were followed-up for 12 months through passive case detection (i.e., the presence of malarial parasites in peripheral blood in case of fever). Anthropometric and hemoglobin measurements and active malaria case detection tests (to detect asymptomatic parasitaemia) were conducted at the beginning and end of the follow-up period of 12 months. Children who had at least one episode of malaria during this period presented lower mean anthropometric index scores compared to children who did not have malaria. We concluded that malaria had a negative impact on the nutritional status of children living in an endemic area at the Western Brazilian Amazon, where Plasmodium vivax predominates.

Evidence of an overweight/obesity transition among school-aged children and youth in Sub-Saharan Africa: a systematic review

BACKGROUND

Prevalence of childhood overweight/obesity has increased considerably in recent years. The transition to higher rates of overweight/obesity has been well documented in high income countries; however, consistent or representative data from lower income countries is scarce. It is therefore pertinent to assess if rates of overweight/obesity are also increasing in lower income countries, to inform public health efforts.

OBJECTIVE

This systematic review aimed to investigate the evidence for an overweight/obesity transition occurring in school-aged children and youth in Sub Saharan Africa.

METHODS

Studies were identified by searching the MEDLINE, Embase, Africa Index Medicus, Global Health, Geobase, and EPPI-Centre electronic databases. Studies that used subjective or objective metrics to assess body composition in apparently healthy or population-based samples of children and youth aged 5 to 17 years were included.

RESULTS

A total of 283 articles met the inclusion criteria, and of these, 68 were used for quantitative synthesis. The four regions (West, Central, East, and South) of Sub Saharan Africa were well represented, though only 11 (3.9%) studies were nationally representative. Quantitative synthesis revealed a trend towards increasing proportions of overweight/obesity over time in school-aged children in this region, as well as a persistent problem of underweight. Weighted averages of overweight/obesity and obesity for the entire time period captured were 10.6% and 2.5% respectively. Body composition measures were found to be higher in girls than boys, and higher in urban living and higher socioeconomic status children compared to rural populations or those of lower socioeconomic status.

CONCLUSIONS

This review provides evidence for an overweight/obesity transition in school-aged children in Sub Saharan Africa. The findings of this review serve to describe the region with respect to the growing concern of childhood overweight/obesity, highlight research gaps, and inform interventions.

PROSPERO REGISTRATION NUMBER

CRD42013004399.

Association between serum zinc concentration and the Plasmodium falciparum antibody titer among rural villagers of Attapeu Province, Lao People's Democratic Republic

Experimental studies have indicated that low serum zinc levels affect immune responses. However, few studies have evaluated the impact of serum zinc levels on antibody responses in the field in developing countries. We investigated an association between the anti-Plasmodium falciparum (Pf) antibody (immunoglobulin G) titer and serum zinc concentration among villagers in rural areas of the Lao People's Democratic Republic. Blood samples were collected to detect Pf infection. An enzyme-linked immunosorbent assay (ELISA) was used to measure the anti-PfIgG antibody titer. Each serum sample was assayed to measure the concentration of zinc. Pearson's correlation coefficient was applied to the association between zinc concentration and anti-PfIgG antibody titers. Multiple linear regression analysis was used to assess the association between zinc concentration and anti-PfIgG antibody titers, controlling for age and albumin level. Of 71 blood samples, 40 were Pf positive and 31 were Pf negative. The median serum zinc concentrations were 56.0 μg/dl in the Pf-positive group and 62.5 μg/dl in the Pf-negative group. The median anti-Pf titers were 833.4 in the positive group and 1237.2 in the negative group. Unexpectedly, there was a negative correlation between serum zinc and anti-Pf IgG antibody titers; the correlation coefficient were -0.453 and (p=0.003) in the positive group and -0.461 (p=0.009) in the negative group. The results of this study indicated sustained antibody responses among the villagers, who had likely been exposed to malaria periodically throughout their lives. Further studies are necessary to determine the conditions in which zinc could be effective against malaria.

Factors associated with malaria parasitaemia, malnutrition, and anaemia among HIV-exposed and unexposed Ugandan infants: a cross-sectional survey

BACKGROUND

Malaria, malnutrition and anaemia are major causes of morbidity and mortality in African children. The interplay between these conditions is complex and limited data exist on factors associated with these conditions among infants born to HIV-uninfected and infected women.

METHODS

Two hundred HIV-exposed (HIV-uninfected infants born to HIV-infected mothers) and 400 HIV-unexposed infants were recruited from an area of high malaria transmission in rural Uganda. A cross-sectional survey was performed at enrolment to measure the prevalence of malaria parasitaemia, measures of malnutrition (z-scores <2 standard deviations below mean) and anaemia (haemoglobin <8 gm/dL). Multivariate logistic regression was used to measure associations between these conditions and risk factors of interest including household demographics, malaria prevention practices, breastfeeding practices, household structure and wealth index.

RESULTS

The prevalence of malaria parasitaemia was 20%. Factors protective against parasitaemia included female gender (OR = 0.66, p = 0.047), mother's age (OR = 0.81 per five-year increase, p = 0.01), reported bed net use (OR = 0.63, p = 0.03) and living in a well-constructed house (OR = 0.25, p = 0.01). Although HIV-unexposed infants had a higher risk of parasitaemia compared to HIV-exposed infants (24% vs 14%, p = 0.004), there was no significant association between HIV-exposure status and parasitaemia after controlling for the use of malaria preventative measures including bed net use and trimethoprim-sulphamethoxazole prophylaxis. The prevalence of stunting, underweight, and wasting were 10%, 7%, and 3%, respectively. HIV-exposed infants had a higher odds of stunting (OR = 2.23, p = 0.005), underweight (OR = 1.73, p = 0.09) and wasting (OR = 3.29, p = 0.02). The prevalence of anaemia was 12%. Risk factors for anaemia included older infant age (OR = 2.05 per one month increase, p = 0.003) and having malaria parasitaemia (OR = 5.74, p < 0.001).

CONCLUSIONS

Compared to HIV-unexposed infants, HIV-exposed infants had a higher use of malaria preventative measures and lower odds of malaria parasitaemia. Having a better constructed house was also protective against malaria parasitaemia. HIV-exposure was the primary risk factor for measures of malnutrition. The primary risk factor for anaemia was malaria parasitaemia. These findings suggest the need to better target existing interventions for malaria, malnutrition and anaemia as well as the need to explore further the mechanisms behind the observed associations.

The association between malnutrition and the incidence of malaria among young HIV-infected and -uninfected Ugandan children: a prospective study

BACKGROUND

In sub-Saharan Africa, malnutrition and malaria remain major causes of morbidity and mortality in young children. There are conflicting data as to whether malnutrition is associated with an increased or decreased risk of malaria. In addition, data are limited on the potential interaction between HIV infection and the association between malnutrition and the risk of malaria.

METHODS

A cohort of 100 HIV-unexposed, 203 HIV-exposed (HIV negative children born to HIV-infected mothers) and 48 HIV-infected children aged 6 weeks to 1 year were recruited from an area of high malaria transmission intensity in rural Uganda and followed until the age of 2.5 years. All children were provided with insecticide-treated bed nets at enrolment and daily trimethoprim-sulphamethoxazole prophylaxis (TS) was prescribed for HIV-exposed breastfeeding and HIV-infected children. Monthly routine assessments, including measurement of height and weight, were conducted at the study clinic. Nutritional outcomes including stunting (low height-for-age) and underweight (low weight-for-age), classified as mild (mean z-scores between -1 and -2 during follow-up) and moderate-severe (mean z-scores < -2 during follow-up) were considered. Malaria was diagnosed when a child presented with fever and a positive blood smear. The incidence of malaria was compared using negative binomial regression controlling for potential confounders with measures of association expressed as an incidence rate ratio (IRR).

RESULTS

The overall incidence of malaria was 3.64 cases per person year. Mild stunting (IRR = 1.24, 95% CI 1.06-1.46, p = 0.008) and moderate-severe stunting (IRR = 1.24, 95% CI 1.03-1.48, p = 0.02) were associated with a similarly increased incidence of malaria compared to non-stunted children. Being mildly underweight (IRR = 1.09, 95% CI 0.95-1.25, p = 0.24) and moderate-severe underweight (IRR = 1.12, 95% CI 0.86-1.46, p = 0.39) were not associated with a significant difference in the incidence of malaria compared to children who were not underweight. There were no significant interactions between HIV-infected, HIV-exposed children taking TS and the associations between malnutrition and the incidence of malaria.

CONCLUSIONS

Stunting, indicative of chronic malnutrition, was associated with an increased incidence of malaria among a cohort of HIV-infected and -uninfected young children living in an area of high malaria transmission intensity. However, caution should be made when making causal inferences given the observational study design and inability to disentangle the temporal relationship between malnutrition and the incidence of malaria.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00527800.

Host immunity as a determinant of treatment outcome in Plasmodium falciparum malaria

Host immunity is an important but poorly understood determinant of antimalarial efficacy, influencing the outcome of prevention and treatment trials. Variations in host immunity might explain why factors such as host genetics, age, pregnancy, infection with HIV, parasite density, and malaria transmission intensity, can raise or lower apparent cure rates. Recently, attempts have been made to characterise immunological correlates of treatment outcome in Plasmodium falciparum malaria, but not yet for Plasmodium vivax. A better understanding of such correlates might improve trials of antimalarial drugs and provide leads for vaccine development. Greater understanding of the relation between host immunity and treatment outcome is crucial to making informed choices about the use of safe but partly effective drugs for malaria prevention in children and pregnant women. With increasing malaria control efforts worldwide, declining population immunity might alter drug response profiles. Improved methods for assessing antimalarial immunity will strengthen malaria control efforts.

Impact of child malnutrition on the specific anti-Plasmodium falciparum antibody response

Background

In sub-Saharan Africa, preschool children represent the population most vulnerable to malaria and malnutrition. It is widely recognized that malnutrition compromises the immune function, resulting in higher risk of infection. However, very few studies have investigated the relationship between malaria, malnutrition and specific immunity. In the present study, the anti-Plasmodium falciparum IgG antibody (Ab) response was evaluated in children according to the type of malnutrition.

Methods

Anthropometric assessment and blood sample collection were carried out during a cross-sectional survey including rural Senegalese preschool children. This cross-sectional survey was conducted in July 2003 at the onset of the rainy season. Malnutrition was defined as stunting (height-for-age <-2 z-scores) or wasting (weight-for-height <-2 z-scores). The analysis was performed on all malnourished children in July (n = 161, either stunted, n = 142 or wasted, n = 19), pair-matched to well-nourished controls. The IgG Ab response to P. falciparum whole extracts (schizont antigens) was assessed by ELISA in sera of the included children.

Results

Both the prevalence of anti-malarial immune responders and specific IgG Ab levels were significantly lower in malnourished children than in controls. Depending on the type of malnutrition, wasted children and stunted children presented a lower specific IgG Ab response than their respective controls, but this difference was significant only in stunted children (P = 0.026). This down-regulation of the specific Ab response seemed to be explained by severely stunted children (HAZ ≤ -2.5) compared to their controls (P = 0.03), while no significant difference was observed in mildly stunted children (-2.5 < HAZ <-2.0). The influence of child malnutrition on the specific anti-P. falciparum Ab response appeared to be independent of the intensity of infection.

Conclusion

Child malnutrition, and particularly stunting, may down-regulate the anti-P. falciparum Ab response, both in terms of prevalence of immune responders and specific IgG Ab levels. This study provides further evidence for the influence of malnutrition on the specific anti-malarial immune response and points to the importance of taking into account child malnutrition in malaria epidemiological studies and vaccine trials.

Schistosomiasis and US Peace Corps volunteers in Tanzania

BACKGROUND

Schistosoma haematobium and Schistosoma mansoni are endemic to East Africa. US Peace Corps volunteers (PCVs) serving in Tanzania were not experiencing symptoms of infection, but in 1998 when comprehensive testing was instituted, more than one-quarter were found to be infected with schistosomiasis at the close of their 27-month tour of service.

METHODS

An education campaign was instituted by the in-country Peace Corps Medical Officers. At their close of service, all PCVs had a medical examination and blood, urine, and stool samples were tested for schistosomiasis. PCVs also answered a survey that included questions about their knowledge of the blood fluke and the disease, symptoms, where and how many times they had gone swimming, and what precautionary measures they had taken.

RESULTS

PCVs in Tanzania are most susceptible to infection from recreational activities within the Lake Victoria ecosystem. After an education campaign, incident cases dropped quickly. Vigorous toweling after exposure may have decreased the risk of disease for those PCVs who went swimming in freshwater. Although schistosomiasis is common in Tanzania and PCVs are highly susceptible, it is possible for them to spend their entire tour without contracting the disease, even if they live by Lake Victoria.

CONCLUSIONS

People should be encouraged not to swim in Lake Victoria. The possibility that vigorous toweling immediately after exposure to infected waters is a useful protective measure warrants further investigation.

Epidemiology of helminth infections and their relationship to clinical malaria in southwest Uganda

It has recently been suggested that helminth infections may adversely influence susceptibility to other infections, including malaria. To investigate this hypothesis in a sub-Saharan African setting, surveys of helminth infections were conducted in 2003 among individuals who had been under weekly active case detection for clinical malaria during the preceding 18 months in four villages in Kabale District, southwest Uganda. Overall, 47.3% of individuals had at least one intestinal nematode species infection: hookworm, Ascaris lumbricoides and Trichuris trichiura were detected in 32.1, 17.4 and 8.1% of individuals, respectively. We found evidence of significant household clustering of A. lumbricoides, T. trichiura and hookworm, and clustering of heavy infection of each species. The association between helminth infection and clinical malaria was investigated in two villages and no evidence for an association was observed between the presence of infection or heavy infection and risk of malaria.

Cachexia in malaria and heart failure: therapeutic considerations in clinical practice

Cachexia is an independent prognostic marker of survival in many chronic diseases including heart failure and malaria. Morbidity and mortality from malaria is high in most of the third world where it presents a very challenging public health problem. Malaria may present in the UK as fever in the returning traveller or as fever in overseas visitors. How and why cachexia develops in malaria in a manner similar to the cachexia of chronic heart failure and the treatment strategies that would alter outcomes in both diseases are discussed in this review.

Nutritional modulation of malaria morbidity and mortality

This review critically examines the relationship between nutritional status and malaria. The data indicate that protein-energy malnutrition is associated with greater malaria morbidity and mortality in humans. In addition, controlled trials of either vitamin A or zinc supplementation show that these nutrients can substantially reduce clinical malaria attacks. Data for iron indicate that supplementation may minimally aggravate certain malariometric indices in some settings and also strongly improve hematologic status. Withholding of iron supplements from deficient population is, therefore, not currently indicated. Available evidence for other nutrients describe varied effects, with some deficiencies being exacerbative (e.g., thiamine), protective (e.g., vitamin E), or both exacerbative and protective in different settings (e.g., riboflavin, vitamin C). The roles of folate, other B vitamins, unsaturated fatty acids, amino acids, and selenium are also examined. Study of the interactions between nutrition and malaria may provide insight to protective mechanisms and result in nutrient-based interventions as low-cost and effective adjuncts to current methods of malaria prevention and treatment.

Nutrition and the commoditization of food in sub-Saharan Africa

During the past decade, Africa, more than any other continent, has been associated with famine and malnutrition. The Sahelian drought of the early 1970s, the Wollo and Karamoja famines and most recently, mass starvation in Ethiopia, have followed one another in rapid succession. The term 'food crisis' continually crops up in the popular and academic press. An increasing number of researchers probe possible causes; many seek a systemic reason for the present situation. One working hypothesis is that increasing commoditization of food has undermined Africa's food systems. This paper does not purport to prove or disprove this. Less ambitiously, its aim is to draw attention to inter-relationships between commoditization and physical and social aspects of African food systems, tracing their possible effects on the nutritional status of the African population. In so doing, some of the complexities of developing food production and consumption in the transition from peasant societies to more urban-based national economies become evident. The paper is divided into three main parts: a discussion of conceptual categories and general background information about sub-Saharan African food zones and commodity and factor markets; a review of literature on rural food availability and nutrition; and a review of urban food availability and nutrition.

Investigation of the nutritional state of children in a Congolese village. I. Anthropometrical data, plasma prealbumin, albumin, immunoglobulins, ferritin, C-reactive protein, circulating immune complexes

The nutritional status of an unselected group of 111 children from the village of Bouansa, People's Republic of the Congo, was studied. Comprehensive clinical examinations, anthropometrical measurements and analysis of albumin, prealbumin, ferritin, C-reactive protein (CRP), IgA, IgG, IgM, IgE, IgG- and IgM-circulating immune complexes (CIC) were carried out. The results show, by anthropometrical classification, a high prevalence of moderate malnutrition. Low levels of plasma proteins and high levels of immunoglobulins and CIC were found. No correlation between anthropometrical classification and plasma proteins was established. Children with increased levels of CRP showed low prealbumin values and increased levels of ferritin. Patterns of immunoglobulins and CIC were close to those found in other studies in tropical countries. To evaluate the anthropometrical and biochemical findings it is necessary to take into consideration the apparently healthy appearance of the children, which shows the degree of adaptation to the limited availability of food and the high rate of acute and chronic infections.

Immediate hypersensitivity, IgE and asthma

Twenty-one asthmatic and twenty-two non-asthmatic children and nine asthmatic adults from two different rural areas of Tanzania, and eight asthmatic children from Dar-es-Salaam were surveyed by questionnaires, skin testing and the measurement of serum IgE. Asthma was significantly commoner in female rural children (four males, fifteen females). The rural asthmatic children apparently had less skin reactivity (in seven of nine tests) and lower specific (in two of four tests) and total serum IgE than age-, sex- and village-matched controls. This pattern of asthma in rural children in the tropics represents a different type of asthma from that found in temperate zones. In contrast, the adult rural asthmatics and the urban children seemed to have the pattern of increased skin reactivity and serum IgE found in asthmatic patients from temperate climates.