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Background: Immune evasion and drug resistance in malaria have been linked to chromosomal recombination and gene copy number variation (CNV). These events are ideally studied using comparative genomic analyses; however in malaria these analyses are not as common or thorough as in other infectious diseases, partly due to the difficulty in sequencing and assembling complete genome drafts. Recently, whole genome optical mapping has gained wide use in support of genomic sequence assembly and comparison. Here, a rapid technique for producing whole genome optical maps of Plasmodium falciparum is described and the results of mapping four genomes are presented., Methods: Four laboratory strains of P. falciparum were analysed using the Argus™ optical mapping system to produce ordered restriction fragment maps of all 14 chromosomes in each genome. Plasmodium falciparum DNA was isolated directly from blood culture, visualized using the Argus™ system and assembled in a manner analogous to next generation sequence assembly into maps (AssemblyViewer™, OpGen Inc.®). Full coverage maps were generated for P. falciparum strains 3D7, FVO, D6 and C235. A reference P. falciparum in silico map was created by the digestion of the genomic sequence of P. falciparum with the restriction enzyme AflII, for comparisons to genomic optical maps. Maps were then compared using the MapSolver™ software., Results: Genomic variation was observed among the mapped strains, as well as between the map of the reference strain and the map derived from the putative sequence of that same strain. Duplications, deletions, insertions, inversions and misassemblies of sizes ranging from 3,500 base pairs up to 78,000 base pairs were observed. Many genomic events occurred in areas of known repetitive sequence or high copy number genes, including var gene clusters and rifin complexes., Conclusions: This technique for optical mapping of multiple malaria genomes allows for whole genome comparison of multiple strains and can assist in identifying genetic variation and sequence contig assembly. New protocols and technology allowed us to produce high quality contigs spanning four P. falciparum genomes in six weeks for less than $1,000.00 per genome. This relatively low cost and quick turnaround makes the technique valuable compared to other genomic sequencing technologies for studying genetic variation in malaria.

More so than any other infectious disease, malaria has all too often affected the conduct of military operations in war and in some cases has disproportionately influenced the outcome. From Napoleon's defensive action at Walcheren, to the Union Army's attempts to take control of the Mississippi River at Corinth and Vicksburg, to the dreadful numbers of malaria casualties suffered by U.S. Marines on the islands of Efate and Guadalcanal during World War II and more recently in Liberia in 2003, malaria has extracted a heavy toll. In this article, we summarize a few of the significant contributions to malaria control by U.S. military personnel throughout its history. We review examples of scientific achievements, medical breakthroughs, and lessons learned from preceding wars that continue to drive the quest for effective antimalarial therapies and preventive vaccines. This review is by no means comprehensive or complete but serves as a testament to the skill, courage, self-sacrifice, and devotion to duty of the many who have faithfully served their country in the past and to those today who continue the struggle against this disease.

The goal of the Malaria Vaccine Program at the Walter Reed Army Institute of Research (WRAIR) is to develop a licensed multi-antigen, multi-stage vaccine against Plasmodium falciparum able to prevent all symptomatic manifestations of malaria by preventing parasitemia. A secondary goal is to limit disease in vaccinees that do develop malaria. Malaria prevention will be achieved by inducing humoral and cellular immunity against the pre-erythrocytic circumsporozoite protein (CSP) and the liver stage antigen-1 (LSA-1). The strategy to limit disease will target immune responses against one or more blood stage antigens, merozoite surface protein-1 (MSP-1) and apical merozoite antigen-1 (AMA-1). The induction of T- and B-cell memory to achieve a sustained vaccine response may additionally require immunization with an adenovirus vector such as adenovirus serotype 35. RTS,S, a CSP-derived antigen developed by GlaxoSmithKline Biologicals in collaboration with the Walter Reed Army Institute of Research over the past 17 years, is the cornerstone of our program. RTS,S formulated in AS02A (a GSK proprietary formulation) is the only vaccine candidate shown in field trials to prevent malaria and, in one instance, to limit disease severity. Our vaccine development plan requires proof of an individual antigen's efficacy in a Phase 2 laboratory challenge or field trial prior to its integration into an RTS,S-based, multi-antigen vaccine. Progress has been accelerated through extensive partnerships with industrial, academic, governmental, and non-governmental organizations. Recent safety, immunogenicity, and efficacy trials in the US and Africa are presented, as well as plans for the development of a multi-antigen vaccine.

Context: Acute eosinophilic pneumonia (AEP) is a rare disease of unknown etiology characterized by respiratory failure, radiographic infiltrates, and eosinophilic infiltration of the lung., Objectives: To describe a case series of AEP, illustrate the clinical features of this syndrome, and report the results of an epidemiologic investigation., Design, Setting, and Participants: Epidemiologic investigation of cases of AEP identified both retrospectively and prospectively from March 2003 through March 2004 among US military personnel deployed in or near Iraq. Survivors were offered a follow-up evaluation., Main Outcome Measure: Morbidity and mortality related to AEP., Results: There were 18 cases of AEP identified among 183,000 military personnel deployed in or near Iraq during the study period, yielding an AEP incidence of 9.1 per 100,000 person-years (95% confidence interval, 4.3-13.3). The majority of patients (89%) were men and the median age was 22 (range, 19-47) years. All patients used tobacco, with 78% recently beginning to smoke. All but 1 reported significant exposure to fine airborne sand or dust. Known causes of pulmonary eosinophilia (eg, drug exposures or parasitic disease) were not identified. Epidemiologic investigation revealed no evidence of a common source exposure, temporal or geographic clustering, person-to-person transmission, or an association with recent vaccination. Six patients underwent bronchoalveolar lavage (median eosinophilia of 40.5%). All patients developed peripheral eosinophilia (range, 8%-42%). Mechanical ventilation was required in 67% for a median of 7 (range, 2-16) days. Two soldiers died; the remainder responded to corticosteroids and/or supportive care. Twelve individuals were reevaluated a median of 3 months after diagnosis. At that point, 3 patients reported mild dyspnea and 1 reported wheezing. All patients had finished treatment and had either normal or nearly normal spirometry results. None had recurrent eosinophilia., Conclusions: AEP occurred at an increased rate among this deployed military population and resulted in 2 deaths. Failure to consider AEP in the differential diagnosis of respiratory failure in military personnel can result in missing this syndrome and possibly death. The etiology of AEP remains unclear, but the association with new-onset smoking suggests a possible link.