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Christine Ahn MD
Carl Allen DDS, MSD
Brandon Ayres MD
Howard P. Baden MD
Robert Baran MD
Keira Barr MD
Gregory J. Basura MD, Ph.D
Donald Belsito MD
Jeffrey D. Bernhard MD
Jesse Berry MD
Victor Blanco MD
Benjamin R. Bohaty MD
William Bonnez MD
Sarah Brenner MD
Robert A. Briggaman MD
Robert Brodell MD
Roman Bronfenbrener MD
Walter Brooks MD
William Buckley MD
Philip Bulterys MD, PhD (candidate)
Susan Burgin MD
Sonya Burton MD
Sean P. Bush MD, FACEP
Jeffrey Callen MD
Scott Camazine MD
Michael Cardwell
Shelley D. Cathcart MD
Robert Chalmers MD, MRCP, FRCP
Chia-Yu Chu MD, PhD
Flavio Ciferri MD
Maria Rosa Cordisco MD
Noah Craft MD, PhD
John T. Crissey MD
Harold E. Cross MD, PhD
Charles Crutchfield III MD
Adriana Cruz MD
Donna Culton MD, PhD
Bart J. Currie MBBS, FRACP, DTM&H
Chicky Dadlani MD
Alexander Dane DO
C. Ralph Daniel III MD
Thomas Darling MD, PhD
William Delaney MD
Damian P. DiCostanzo MD
Ncoza Dlova MD
James Earls MD
Libby Edwards MD
Melissa K. Egge MD
Charles N. Ellis MD
Rachel Ellis MD
David Elpern MD
Nancy Esterly MD
Stephen Estes MD
E. Dale Everett MD
Janet Fairley MD
David Feingold MD
Benjamin Fisher MD
Henry Foong MBBS, FRCP
David Foster MD, MPH
Brian D. Foy PhD
Michael Franzblau MD
Vincent Fulginiti MD
Sunir J. Garg MD, FACS
Kevin J. Geary MD
Lowell Goldsmith MD, MPH
Sethuraman Gomathy MD
Bernardo Gontijo MD, PhD
Kenneth Greer MD
Kenneth G. Gross MD
Alan Gruber MD
Nathan D. Gundacker MD
Akshya Gupta MD
Vidal Haddad MSC, PhD, MD
Edward Halperin MD, MA
Ronald Hansen MD
John Harvey
Rizwan Hassan MD
Michael Hawke MD
Jason E. Hawkes MD
Peter W. Heald MD
David G. Hicks MD
Sarah Hocker DO
Ryan J. Hoefen MD, PhD
Li-Yang Hsu MD
William Huang MD
Sanjana Iyengar MD
Alvin H. Jacobs MD
Saagar Jadeja MD
Shahbaz A. Janjua MD
Joshua J. Jarvis MD
Kit Johnson
Robert Kalb MD
A. Paul Kelly MD
Henry Kempe MD
Loren Ketai MD
Sidney Klaus MD
Ashwin Kosambia MD
Jessica A. Kozel MD
Carl Krucke
Mario E. Lacouture MD
Joseph Lam MD
Alfred T. Lane MD
Edith Lederman MD
Nahyoung Grace Lee MD
Pedro Legua MD, PhD
Robert Levin MD
Bethany Lewis MD
Sue Lewis-Jones FRCP, FRCPCH
Taisheng Li MD
Christine Liang MD
Shari Lipner MD, PhD
Adam Lipworth MD
Jason Maguire MD
Mark Malek MD, MPH
Jere Mammino DO
Ricardo Mandojana MD
Lynne Margesson MD
Thomas J. Marrie MD
Maydel Martinez MD
Ralph Massey MD
Patrick McCleskey MD
Karen McKoy MD
Thomas McMeekin MD
Josette McMichael MD
Somchai Meesiri MD
Joseph F. Merola MD
Mary Gail Mercurio MD
Anis Miladi MD
Larry E. Millikan MD
Dan Milner Jr. MD
Zaw Min MD
Stephanie Montero
Alastair Moore MD
Keith Morley MD
Dean Morrell MD
Samuel Moschella MD
Taimor Nawaz MD
Vic Newcomer MD
John Nguyen MD
Matilda Nicholas MD
Thomas P. Nigra MD
Steven Oberlender MD, PhD
Maria Teresa Ochoa MD
Art Papier MD
Lawrence Parish MD
Tanner Parrent MD
Mukesh Patel MD
Lauren Patty-Daskivich MD
David Peng MD, MPH
Robert Penne MD
Nitipong Permpalung MD
Miriam Pomeranz MD
Doug Powell MD
Harold S. Rabinovitz MD
Christopher J. Rapuano MD
Sireesha Reddy MD
Angela Restrepo MD, PhD
Bertrand Richert MD, PhD
J. Martin Rodriguez, MD, FACP
Theodore Rosen MD
Misha Rosenbach MD
Scott Schiffman MD
Robert H. Schosser MD
Glynis A. Scott MD
Carlos Seas MD, MSc
Deniz Seçkin MD
Daniel Sexton MD
Paul K. Shitabata MD
Tor Shwayder MD, FAAP, FAAD
Elaine Siegfried MD
Gene Sienkiewicz MD
Christye Sisson
Philip I. Song MD
Mary J. Spencer MD, FAAP
Lawrence B. Stack MD
Sarah Stein MD
William Van Stoecker MD
Frances J. Storrs MD
Erik J. Stratman MD
Lindsay C. Strowd MD
Erika Summers MD
Belinda Tan MD, PhD
Robert Tomsick MD
Hensin Tsao MD, PhD
Jenny Valverde MD
Vishalakshi Viswanath MD
Susan Voci MD
Lisa Wallin ANP, FCCWS
Douglas Walsh MD
Ryan R. Walsh MD
George Watt MD
Clayton E. Wheeler MD
Sally-Ann Whelan MS, NP, CWOCN
Jan Willems MD, PhD
James Henry Willig MD, MPH
Karen Wiss MD
Vivian Wong MD, PhD
Sook-Bin Woo MS, DMD, MMSc
Jamie Woodcock MD
Stephen J. Xenias MD
Lisa Zaba MD
Vijay Zawar MD
Bonnnie Zhang MD
Carolyn Ziemer MD
Organizations
Am. Journal of Trop. Med & Hygiene
Armed Forces Pest Management Board
Blackwell Publishing
Bugwood Network
Centers For Disease Control and Prevention
Centro Internacional de Entrenamiento e Investigaciones Mèdicas (CIDEIM)
Dermatology Online Journal
East Carolina University (ECU), Division of Dermatology
Uncomplicated
Malaria is a parasitic infection of red blood cells by Plasmodium species. The route of infection is via the bite of an infected female Anopheles mosquito. Less commonly, malaria may be transmitted via transfusion of blood products or by vertical transmission. In the United States, physicians encounter malaria as one of most common causes of acute febrile illness in travelers returning from endemic areas, especially sub-Saharan Africa and South Asia. In addition, cases of malaria in the United States have increasingly been found in refugees relocating from sub-Saharan Africa to the United States.
Approximately 1500 cases of malaria are reported in the United States each year. Most are diagnosed in travelers returning from malaria-endemic regions (from high to low risk: West Africa, Oceania, other parts of Africa, South Asia, South America, Central American, and other parts of Asia). Five Plasmodium species are responsible for human disease: Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium knowlesi. Geographic distribution of each species is different. Plasmodium falciparum is more likely to be identified as a cause of malaria in travelers returning from Africa, and P. vivax is more likely to be identified as a cause of malaria in travelers returning from Asia, Central America and the Caribbean, or South America. Plasmodium knowlesi is a simian malaria species that has increasingly been recognized as the cause of human infection in Malaysian Borneo and surrounding countries. Coinfection with more than one species of malaria can occur in regions where multiple Plasmodium species are present.
The typical incubation period is 9-18 days, except for P. malariae, for which it is longer (18-40 days); 80% of malaria cases with known onset of illness reported symptoms within 30 days after return from travel (90% of cases with P. falciparum but only 54% of cases with P. vivax).
Symptoms of uncomplicated malaria are nonspecific and include fever, headache, back pain, chills, sweating, myalgia, nausea, vomiting, diarrhea, and cough. Differentiating malaria from other infectious and non-infectious diseases is difficult if based on clinical symptoms alone.
The fever may become paroxysmal, preceded by rigors for 1-2 hours and followed by an intense diaphoresis. Regularly periodic fever may be seen with P. vivax or P. ovale, with a febrile episode every 48 hours (tertian fever), or with P. malariae, with a febrile episode every 72 hours (quartan fever).
Relapsing malaria may occur with P. vivax and P. ovale, both of which have a dormant hypnozoite liver stage as part of the life cycle. Relapses can occur months or even years after infection.
Malaria should be included in the differential diagnosis of every patient with acute febrile illness and travel history to endemic areas.
Patients with severe or complicated malaria, which has very high mortality, may present with prostration, coma, respiratory distress (acidotic breathing), severe anemia, renal failure, acute respiratory distress syndrome (ARDS), pulmonary edema, hypoglycemia, shock, disseminated intravascular coagulation (DIC), bleeding, and convulsion.
Species identification is important because uncomplicated malaria with P. falciparum can rapidly develop into severe infection, though any species can cause severe disease. Physicians cannot rely on symptoms and signs to diagnose malaria or to specify the infecting species.
Malaria mainly due to P. falciparum has been associated with increased susceptibility and severity among pregnant women.
