Mapping one year of cholera morbidity and mortality rates in Haiti.

<p>The colored scales represent yearly attack (a) and mortality (b) rates per 10,000 inhabitants in communes of Haiti (from October 16, 2010 to October 15, 2011).</p

Daily incidence rates (DIRs) and high-risk spatial clusters for each epidemic phase.

<p>Daily incidence rates (DIRs) and high-risk spatial clusters for each epidemic phase.</p

Spectral analysis of time series.

<p>Analysis of cases (a), rainfall (b), and cross-wavelet (c) between cases and rainfall are presented. The Y-axes represent length of the wavelet analysis window (from 3 to 26 days) and the color scales represent the spectral values for each length of the analysis window.</p

Impact of local environmental factors during each epidemic phase.

<p>Standardized incidence ratios (p-values) were estimated using the multivariate regression model.</p>*<p>Factor excluded using stepwise analysis.</p>†<p>Significant factors (boldface).</p>‡<p>Non-significant factors kept using stepwise analysis.</p

<i>P. falciparum</i> responsive T cell subtypes identify asymptomatic malaria patients.

<p>PBMCs from malaria patients were co-cultured for 6 days with lysate from uRBC or <i>P</i>. <i>falciparum</i> schizonts (iRBC lysate) at a lymphocyte to parasite ratio of 1:2. Changes in the percentages of T cell subpopulations during culture were compared between asymptomatic (n = 9, Asymp) and symptomatic (n = 6, Symp) patients in <b>(A)</b> NKT-like T cells, <b>(B)</b> CD8^mid T cells, <b>(C)</b> γδ T cells, <b>(D)</b> CD56⁺ γδ T cells, <b>(E)</b> CD4⁺ T cells, and <b>(F)</b> CD25⁺ CD127^low T regulatory cells. Data are represented as box and whisker plots, with box ends extending from the first to the third quartile and the median in the center. Whiskers extend to the highest and lowest data point. Statistical significance was determined using a two-tailed Wilcoxon matched-pairs signed rank test (iRBC lysate vs. uRBC for each patient). * = p-value < 0.05, ** = p-value < 0.01.</p

T cell subtypes and reciprocal inflammatory mediator expression differentiate <i>P</i>. <i>falciparum</i> memory recall responses in asymptomatic and symptomatic malaria patients in southeastern Haiti

<div><p>Asymptomatic <i>Plasmodium falciparum</i> infection is responsible for maintaining malarial disease within human populations in low transmission countries such as Haiti. Investigating differential host immune responses to the parasite as a potential underlying mechanism could help provide insight into this highly complex phenomenon and possibly identify asymptomatic individuals. We performed a cross-sectional analysis of individuals who were diagnosed with malaria in Sud-Est, Haiti by comparing the cellular and humoral responses of both symptomatic and asymptomatic subjects. Plasma samples were analyzed with a <i>P</i>. <i>falciparum</i> protein microarray, which demonstrated serologic reactivity to 3,877 <i>P</i>. <i>falciparum</i> proteins of known serologic reactivity; however, no antigen-antibody reactions delineating asymptomatics from symptomatics were identified. In contrast, differences in cellular responses were observed. Flow cytometric analysis of patient peripheral blood mononuclear cells co-cultured with <i>P</i>. <i>falciparum</i> infected erythrocytes demonstrated a statistically significant increase in the proportion of T regulatory cells (CD4⁺ CD25⁺ CD127^-), and increases in unique populations of both NKT-like cells (CD3⁺ CD8⁺ CD56⁺) and CD8^mid T cells in asymptomatics compared to symptomatics. Also, CD38⁺/HLA-DR⁺ expression on γδ T cells, CD8^mid (CD56^-) T cells, and CD8^mid CD56⁺ NKT-like cells decreased upon exposure to infected erythrocytes in both groups. Cytometric bead analysis of the co-culture supernatants demonstrated an upregulation of monocyte-activating chemokines/cytokines in asymptomatics, while immunomodulatory soluble factors were elevated in symptomatics. Principal component analysis of these expression values revealed a distinct clustering of individual responses within their respective phenotypic groups. This is the first comprehensive investigation of immune responses to <i>P</i>. <i>falciparum</i> in Haiti, and describes unique cell-mediated immune repertoires that delineate individuals into asymptomatic and symptomatic phenotypes. Future investigations using large scale biological data sets analyzing multiple components of adaptive immunity, could collectively define which cellular responses and molecular correlates of disease outcome are malaria region specific, and which are truly generalizable features of asymptomatic <i>Plasmodium</i> immunity, a research goal of critical priority.</p></div

Map of the department of Sud-Est Haiti displaying sites of asymptomatic and symptomatic malaria patients were collected.

<p>Map of the Department of Sud-Est, Haiti with clinical sites La Brésilienne (LB) and Anse à Boeuf (AB) where individuals’ samples were collected from these two respective villages. The two sites were over 70 km apart in distance, and had poorly traversable roads between the two villages. Map of the island of Hispaniola (insert) displaying the two countries Haiti and the Dominican Republic is included. A topographic scale is provided for reference purposes. Maps were provided by Wikipedia and Wikimedia Commons, and were modified to display sample sites accurately.</p

Analysis of CD38⁺/HLA-DR⁺ activation status of T cell sub-populations in asymptomatic and symptomatic malaria patients.

<p>Co-expression of CD38 and HLA-DR on T cells has been suggested as a marker of activation for malaria reactive T cells. The expression of these surface markers was analyzed in T cell subpopulations from asymptomatic (n = 9) and symptomatic (n = 6) patient PBMCs during exposure to <i>P</i>. <i>falciparum</i> strain H1064 infected erythrocytes (iRBC lysate) or uninfected erythrocytes (uRBC). Exposure to <i>P</i>. <i>falciparum</i> antigens diminished the activation status of γδ T cells <b>(A)</b>, CD^mid T cells <b>(B)</b>, and NKT-like T cells <b>(C)</b>. Statistical significance was determined using a two-tailed Wilcoxon matched-pairs signed rank test (iRBC lysate vs. uRBC for each patient). * = p-value < 0.05, ** = p-value < 0.01.</p

Demographics of the participants from Sud-Est, Haiti.

<p>Demographics of the participants from Sud-Est, Haiti.</p

IgG: Top 20 <i>P</i>. <i>falciparum</i> antigens by magnitude recognized by patient sera.

<p>IgG: Top 20 <i>P</i>. <i>falciparum</i> antigens by magnitude recognized by patient sera.</p