THIRD EDITION TROPICAL INFECTIOUS DISEASES

RICHARD L. GUERRANT MDThomasDAV'ID H. WALKERMD PETER F. WELLER MO FACP FIOSA çarmage and Martha Walls Distinguished H. Hunter Professor of Professor of Medicine, Harvard Medical University Chair in Tropical Diseases International Medicine School Director, Center for Biodefense and Director, Center for Global Health, Professor, Immunology and Infectious Emerging Infectious Diseases Division of Infectious Diseasesand Diseases Department, Harvard School of Professor and Chair, Department of International Health Pubüc Health University ofVirginia School of Medicine Pathology Crnef, Infectious Disease Division University ofTexas Medical Branch Charlottesville, VA, USA Vice Chair of Research, Department of Galveston, TX, USA Medicine, Beth Israel DeaconessMedica! Center Boston, MA, USA

Edinburgh, London, New York, Oxford, Philadelphia, SI Louis, Sydney I Toronlo SAUNDERS ELSEVIER

SAUNDERS is an imprint of EIsevier Inc. @ 20 I I, EIsevier Inc. AlI rights reserved.

First edition 1999 Secondedition 2006

No pa;rt of this publication mar be reproduced or transmitted in any form or by any means,electronic or mechanical,including photocopying,recording, or any information storageand retrieval system,without permission in writing Eramthe publisher. Oetails on how to seekpermission, further information about the Publisher'spermissions policies and our arrangementswith organizationssuch asthe Copyright ClearanceCenter and the Copyright LicensingAgency, can be found at our website: www.elsevier. comi permissions.

This book and the individual contributions containedin it are protected under copyright by the Publisher (other than as mar be noted herein).

Chapter 41, Plague,Paul S. Mead is in the public domain apart from any borrowed figures. Chapter60, Enterovirus ,lncluding Poliomyelitis,MarkA. Pallanschis in the public domainapart from any borrowed figures. Chapter 62, Calicivirus Infections, GagandeepKang, Mary K. Estes,Robert L. Atmar -Mary K. Estes retains copyright of her text and images. Chapter 90, Entomophthoramycosis,Lobomycosis, Rhinosporidiosis, and Sporotrichosis, Duane R. Hospenthalis in the public domain apart Eramany borrowed figures. Chapter 99, AmericanTrypanosomiasis (Chagas Disease), Louis v: Kirchhoff is in the public domain apart from any borrowed figures. Chapter 105, Loiasisand MansonellaInfections, Amy D. Klion, ThomasB. Nutman is in the public domain apart Eramany borrowed figures. Chapter 128, Infectious Diseasesin Modern Military Forces,Alan J. Magill, BonnieL. Smoak,Truman W Sharpis in the public domain apart from any borrowed figure~. .

Notices Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment mar become necessary. Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. In using such information or methods they should be mindful of their own safetY,and the safety of others, including parties for whom they have a professional responsibility. With respect to any drug or pharmaceutical products identified, readers are advised to check the most current information provided (i) on procedures featured or (li) by the manufacturer of each product to be administered, to verify the recommended dose or formula, the method and duration of administration, and contraindications. It is the responsibility of practitioners, relying on their own experience and knowledge of their patients, to make diagnoses, to determine dosages and the best treatment for each individual patient, and to take alI appropriate safety precautions. To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, plfoducts, instructions, or ideas contained in the material herein.

Saunders

British Library Cataloguing in Publication Data your sourcefor books. joumals and multimedia in the health sciences ropical infectious diseases: principies, pathogens and practice. 3rd ed. www.elsevierhealth.com 1. Tropical medicine. I. Guerrant, Richard L. 11. Walker, Oavid H., 1943- 111.Weller, reter F. Working together to grow 616.9'883-dc22 libraries in developing countries www.elsevier.com I www.bookaid.org I www.sabre.org ISBN-13:9780702039355

A catalogue record for this book is available from the British Library

Library of Congress Cataloging in Publication Data A catalog record for this book is available from the Library of Congress The publisher's policyis to use papermanufactured Printed in China from sustainableforests 987654 3 2 Last digit is the print number: 987654 3 2 I Robert B. Tesh.Pedro F.C. Vasconcelos

anorexia, ,, and low back pain.8The face is often flushed and the conjunctivae are injected, but a true rash is absent. The disease The family Bunyav;r;daeincludes more than 300 antigenically distinct is self-limited, and the symptoms usually disappearWithin 2-3 days; members, most of which are transmitted by arthropods.! At least 4-1 of however, a general feeling of weakness and depression frequently lasts these have been associatedwith human illness in the tropics. Apart for a week or more after the illness. Marked leukopenia «4000/~L), from those members that produce serious and sometimes fatal disease consisting of initial lymphopenia, followed by protracted neutropenia, (i. e., the hantaviruses, Rift Valley rever , and Crimean-Congo hem- algo occurs in PF.8 orrhagic rever virus), most of the remaining human pathogenic bunya- Aseptic meningitis is a relatively common manifestation of Toscana vírus . Originally described in central ltaly, this infection occurs viruses produce nonspecific febrile illnesses. Becauseof ,their nonspecific nature and the limited virus diagnostic capabilities in many tropical throughout much of the Mediterranean region of Europe and is a frequent countries, these infections are often unrecognized or are misdiagnosed as causeof summertime meningitis in both adults and children.9These cases begin as classic PF, with a nonspecific febrile illness for 2-+ days before other common febrile illnesses such as malaria or dengue. This chapter Robert B. Tesh .Pedro F.C. Vasconcelos describes some of the more common bunyavirus reverso the appearance of more serious symptoms, such as nuchal rigidity, posi- tive Kernig's sign, nystagmus, and reduced levels of consciousness.7In these casesthe hematologic picture is similar to that of classic PF, but the cerebrospinal fluid (CSF) mar show increased pressure, but Without pleocytosis and With normal glucose and protein levels. The neurologic Historically, phlebotomus rever (PF) has been mainly a diseaseof military abnormalities usually resolve in a few days, and most patients recover importance, since have typically occurred when large numbers spontaneously in 1-2 weeks, although headache mar persistoThe recov- of nonimmune adults enter an area of endemic virus activity. The disease ery of phlebovíruses from patients with PF is uncommon, since the occurred in troops during the Napoleonic Wars, the Austrian occupation víremia associatedWith this diseaseis quite transient (24-36 hours), and of the Adriatic, the British colonization of lndia and Pakistan, and the most patients do not seek medical care so earlY.Jge one exception is North African and Mediterranean campaigns in World War 1I.2.3The patients With neurologic diseasedue to Toscanavírus infection; vírus can largest reported outbreak of PF occurred in Serbia in 1948, when over 1 be recovered from the CSF after it has disappeared from the .6 million persons were affected. PF outbreaks still occur among tourists Culturein Vero cells is the isolation system of choice for most phleboví- vacationing in the Mediterranean region.+-7 ruses.2 RT-PCR can algO be dane on CSF of patients With neurologic Many of the PF group of viruses arrear to be maintained in their insect symptoms ofToscana vírus infection. vectors by vertical (transovarial) virus transmission.3 Consequently, virus A number of serologic techniques can be used for the diagnosis activity is largely correlated with adult sandf1yactivity rather than by the of PF, but each has its limitations. The IgM-capture enzyme-linked immune status of the local human or animal populations. During periods immunosorbent assar (ELISA)10 and plaque reduction neutralization of vector abundance (i.e., summer in subtropical or Mediterranean cli- test (PRNT)2.8,11are quite specific and sensitive, but one must screen mates and the rainy seasonin drier tropical climates), phlebovirus activity againsta variety of phlebovírus serotypes because of their focal and some- is continuous. In this situation one seeslittle illness in the native popula- times overlapping distribution. Seroconversion can be demonstrated in tion, most of whom are already immune, but when a group of nonim- paired samples by IgG ELISA and by fluorescent (FA) or mune adults (i. e., tourists, soldiers) enters in the area, an hemagglutination-inhibition (HI) tests, but these techniques are not . k1 2 qmc y ens~es., serotype-specific. Although more than 40 PF virus serotypes have been described,2three Treatment of PF is symptomatic. Except for patients With neurologic virus serotypes (Naples, Sicilian, and Toscana) account for most of the symptoms, as in Toscanavírus infection, hospitalization is usually unnec- recognized PF cases. This is probably because their sandf1y vectors essary.The headacheassociated With PF can be severe, and narcotics are (Phlebotomuspapatasi, R perniciosus,and R perfiliewi) are highly anthro- sometimes needed for relief. PF is a self-limited, nonfatal disease,and pophilic, readily enter houses, and have a wide geographic distribution in recovery is complete. One attack of PF confers lifelong immunity against the Mediterranean region and central Asia.3In contrast, most of the New the infecting vírus type but not against heterologous serotypes.8,11Thus, World phleboviruses and their vectors have a more focal and sylvan dis- second casesof the disease can occur among persons livíng in regions tribution; consequently, PF casesin this region are infrequent and occur where more than one phlebovírus is active. There are no vaccines for mainly in persons who enter forested areas for work or recreation. PF. Contrai measures are directed against the vector and include house- After an of 3-5 days, PF begins suddenly with hold spraying with residual insecticides, bednets, and the use of insect rever, severe frontal headache, retro-orbital pain, photophobia, malaise, repellents.3 4-81 OROPOUCHEFEVER Oropouche fever is a rnidge-borne viral diseasethat has emerged during Group C and Guama viruses are found throughout the New World the past 50 years asan important public health problem in tropical South tropics and subtropics, including Florida, Mexico, Central America, and America. 12.13Thecausative agent, Oropouche virus (genus ), the warmer regions of northern South America.14 At least 25 different was first isolated from the blood of a febrile forest worker in Trinidad in vírus serotypes have been identified. Most of 'tlle serotypes have focal 1955. Since 1961, more than 30 outbreaks of Oropouche virus have been distribution which coincides with forest or forest-fringe habitats, usually reported from the Amazon regions of Brazil and Peru and from Panama. inin low-lying low-lying swampy swampy areas. areas.These These viruses viruses are are maintained maintained in in continuous continuous The number of persons affected has varied with each outbreak, but the sylvansylvan cycles cycles involving involving mosquitoes, mosquitoes, mainly ~nly Culex Culex of of the the subgenus subgenus two largest recorded epidemics (Belem and Manaus, Brazil, in 1980 and Melanoconion,Melanoconion,and and small small mammals mammals such such as asrodents rodents and and marsupiaIs. marsupiais. Humans Humans 1981) each involved about 100000 people.12 areare usually usually infected infected when when they they enter enter the the swampy swampy forest forest habitats habitats where where It is postulated that Oropouche virus is maintained in two distinct thesethese viruses viruses are are endernic endemic and and are are bitten bitten by by infected infected mosquitoes. mosquitoes. Cases Cases cycles: (1) an epidemic urban cycle involVing the biting midge Culicoidesareare usually usually sporadic; sporadic; and and because because of of their their nonspecific nonspecific nature, nature, they they paraensis;and (2) a silent maintenance cycle in which forest animais ( areare usually usually not not reported, reported, ÇJr orare are misdiagnos~d, misdiagno~ed, so so their their true true incidence incidence and possibly monkeys) are the principal vertebrate hosts, and a yet un- isis unknown. unknown. identified arthropod serves as the vector.12 However, the epiderniology PersonsPersonsinfected infected by by group group C C and and Guama Guama group group viruses viruses develop develop sudden sudden of this disease is still not fully elucidated, as it is easily confused with reverrever (38-40°C), (38-40°C), severe severe headache, headache, vertigo, vertigo, myalgia, Illyalgia, retro-orbital retro-orbital pain, pain, dengue and other acutefebrile illnesses,and the true incidence is unknown. malaise,malaise, and and nausea. nausea.The The rever rever lasts lasts 2-5 2-5 days days and and is is sometimes sometimes biphasic. biphasic. Oropouche fever is characterized by the abrupt onset of fever (up to RashRash is is absent. absent. Patients Patients recover recover with with weakness weaknessand and anorexia anorexia lasting lasting 1 1or or 4QOC), chills, severe headache, mayalgia, arthralgia, anorexia, weakness, 2 2weeks, weeks, but but without without sequelae. sequelae. dizziness, and photophobia.12.13Nausea, vorniting, , and epigas- TheseThese viruses viruses can can be be recovered recovered from from patients' patients' gera seTa duringduring the the acute acute tric pain mar also occur. Some Oropouche fever patients can present with febrilefebrile phase phase of of the the illness. illness. They They grow grow well well in in a avariety variety of of cell cell cultures cultures a clinical picture of aseptic meningitis or . Rash is andand kill kill newborn newborn rnice mice and and hamsters. hamsters. Antibodies can can algo also be be detected detected in in rarely present, but leukopenia is a common feature of this disease.The pairedpaired acute acute and and convalescent convalescent gera seTa byby HI, HI: CF, CF, ELISA, ELISA, IFA, IFA, and and PRNT. PRNT. acute clinical illness usually lasts 2-5 days, although a period of asthenia TreatmentTreatment is is nonspecific nonspecific and and supportive. supportive. The The major major risk risk factor fáctor is is occupa- occupa- and occasionally dizziness mar persist for up to a month. A significant tion;tion; avoidance avoidanceof of swampy swampy forest forest habitats habitats and and personal personal.protection protection against against percentage of patients (as high as 60% in some outbreaks) have a recru- mosquitomosquito bites bites are are the the only only prevention. prevention. descence of their original symptoms within 2-10 days after they become afebrile. 12The recurrent illness associated with Oropouche fever see"ms to occur more commonly in persons who quickly resuke strenuous BWAMBA, ILESHA,ANO TATAGUINE activities. No virus can be isolated from the patient's serum during the recurrent illness, and detectable humoral antibodies are usually present. VIRUS INFECTIONS Oropouche virus can often be recovered from the patient's serum TheseThese three three bunyaviruses bunyaviruseshave have been been isolated isolated repeatedly repeatedly from from sick sick persons persons during the first 2-4 days of the disease. The virus can be isolated in andand mosquitoes mosquitoes in in East, East, Central, Central, andWestAfrica.IS.16The andWestAfrica.1S,16The diseasesdiseases associ- associ- newborn mice, adult hamsters, and a variety of mammalian cell cultures. atedated with with them them are are similar: similar: the the acute acute onset onset of of rever, fever, headache, headache, vertigo, vertigo, ~'" ~o Oemonstration of virus-specmc antibody can be demonstrated in paired severemayalgia,severe mayalgia, and and rash, rash, lasting lasting 4-5 4-5 days days and and followed followed by by a aweek week or or ~z"t acute and convalescent phase sera by ELISA, IFA, HI, complement ~o moremore of ofasthenia. asthenia. No No deaths deaths or or serious serious complications complications have have been been reported. reported. o~ fixation (CF), or PRNT. Treatment is symptomatic. No fatalities have MostMost of ofthe the mosquito isolations isolations of of Bwamba, Bwamba, Ilesha, Ilesha, and and TataguineTataguine viruses viruses ]:I:: been reported with Oropouche fever; and fifelong immunity follows havehave been been made made from from Anopheles Anophelesand and Aedesspecies.IS species.lS The The viruses viruses are are ~"... recovery. thoughtthought to tobe be maintained maintained in in a mosquito-wild a mosquito-wild vertebrate vertebrate cycle, cycle, but but little little ~ There is no vaccine against Oropouche fever. Given our limited otherother information information is isavailable. available. Given Given their their demonstrated demonstrated disease disease poten- poten- ~ knowledge of the maintenance cycle of Oropouche virus, vector controf tial,tial, wide wide geographic geographic distribution, distribution, and and the the relatively relatively high high antibody antibody rates rates appears to be the best prevention and control strategy. C. paraensisis a foundfound in in serosurveys serosurveys among among humans humans in in some some African African countries,IS.16 countries,IS,16it it ~ daytime feeder and, because of its tiny size, readily passes through seemsseems likely likely that that these theseagents agents areare of ofgreater greater health health importance importance to tothe the local local ~ window screens. Spraying or fogging in and around houses with residual populationspopulations and and to to visitors visitors than than is iscurrently currently recognized. recognized. But But because becauseof of insecticides is oflirnited value in the control of adult peridomestic popula- thethe paucity paucity of offunctioning functioning virus virus laboratories laboratories in inAfrica Africa and and the the nonspecific nonspecific tions of this rnidge vector. Cleaning up rotting vegetation (e.g., banana naturenature of of illness illness associated associated with with them, them, most most of of these these infections infections are are stalks, decomposing fruit) around houses can help to eliminate C. paraensisprobablyprobably never never recognized recognized or or reported. reported. Diagnosis Diagnosis can can be be made made by by virus virus larval breeding sites. Insect repellent applied to exposed skin also reduces isolationisolation from from blood blood during during the the febrile febrile period period or or by by antibody antibody detection detection the number of bites. in inpaired paired acute acute and and convalescent convalescentgera. seTa.

482

Accessthe completereference list online at http://www.expertconsult.com