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Important Problems on Returning from the Tropics. Bruno Bernardin MD, FRCP, CSPQ. Objectives. Learn to recognize this presentation ... Learn to recognize this rash … Learn when and where to hide from patients Learn when to call funeral pre-arrangements Who’s toast, who’s not. Objectives.
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Important Problems on Returning from the Tropics Bruno Bernardin MD, FRCP, CSPQ
Objectives • Learn to recognize this presentation ... • Learn to recognize this rash … • Learn when and where to hide from patients • Learn when to call funeral pre-arrangements • Who’s toast, who’s not
Objectives • What is NOT malaria • Why is the epidemiology of infectious diseases changing • Recognize the most dangerous illnesses you can come across and prevent a disaster • Build a differential diagnosis from syndromic approach (as you may rarely come across these entities) • Maybe a few other goodies...
Case 1: return of the prodigal son • Young man, 27 y.o., returned x 36 hrs from Cameroun where he visited his family x 1 mo • Fever, chills, malaise, apetite loss • Normal physical exam, To 39o, non toxic
Case -2: Asia • Presents post trip to Thailand-Vietnam • Sore throat, dry cough, headache, myalgias, malaise, fever… • Exam non specific, some lymph nodes
Case-3 • Patient returns from Middle East (or new immigrant) • Cough, wheezing, SOB • New onset asthma, in crisis • Better with B-agonists • CBC: eosinophilia
Syndromes • Fever: • Hemorragic manifestations : • Transmissible: Ebola, Marburg, Lassa, Congo-Crimean • Non transmissible: yellow fever, HD • Respiratory manifestations • Neurological manifestations • Symptoms non specific: dengue, typhoid, malaria • With eosinophilia • Diarrhea • Hematuria • Cutaneous manifestations
Fever in a traveler • 3% of travelers • Focus on life threatening, treatable, or transmissible • Incubation period may allow to eliminate certain pathologies: • >21 days = NOT dengue, viral hemorragic, ricketsioses...
Small exercise: Typical picture : • fever, malaise • myalgias, headache • chills, anorexia • nausea, vomiting • +/- diarrhea DIAGNOSIS??
Hemorragic Fevers • Initial approach : isolate, isolate, isolate… • Differential diagnosis : • meningococcemia • gram negative sepsis • viral (not in the sense: “it’s just a virus, it’ll pass”)
Hemorragic Fevers • 18 viruses identified • 4 have person to person transmission • Short incubation period • History of a trip (or contact having travelled!) • Increase in vascular permeability universal • Hemorragic component not universal!!
Hemorragic Fevers • Ebola • Marburg • Dengue • Yellow fever • Lassa • Congo-Crimean
Ebola - Filoviridae • 4 sub-types: • 3 pathogenic in humans: African strains • 1 pathogenic in monkeys: Reston • Reservoir: unknown • Region: RDC-Zaire, Soudan, Gabon, Côte-d’Ivoire, Uganda • Transmission: direct contact (sweat glands), biological fluids • aerosol: only for Reston • nosocomial +++
Ebola- 2 • Sudden onset : To, myalgias, sore throat, headache, asthenia ++, No-Vo-diarrhea • Hemorragic manifestations: day 5-7 • Conjonctival injection, rash • Death in shock • Viral replication in and damage to vascular endothelium , hepatic destruction • Mortality: 50-88%
Congo-Crimean - Bunyaviridae • Most widely spread HF in the world: Eastern Europe to the steppes of Asia, Africa, China • Transmitted by ixode tick bite or person to person via secretions (vomit, blood especially) • Low infectivity in nature • Farm workers : cows, sheep, milk
Congo-Crimean • Sudden onset: To, myalgias (back), epiG pain • Conjonctivitis, hyperhemia pharynx, soft palate petechiae • Hemorrhage 3rd-5th day: hematuria, ecchymoses +++, oral, GI • Plt < 20 000, PT >60 s, AST >200, ALT >150: BAD!! • Tx: ribavirin
Lassa - Arenaviridae • West Africa : Nigeria to Guinee • South America: Venezuela, Argentina, Bolivia (other viruses) • Transmission: secretions form contaminated animals (rodents) • humans: blood, secretions • 1 illness : 4-5 infected; • lethality 2-3%, 20-30% pregnant women!
Lassa • Onsetinsidious: To, weakness, malaise; arthralgias, lombar pain • Dry cough, chest pain, Vo-diarrhea; pharyngitis • Bleeding: only 15-20%, oral especially • Oedema of face and neck or high LFT’s: BAD! • Ribavirin could decrease mortality
Yellow Fever - Flaviviridae • Virus amaril • Transmission: mosquito bite • Reservoirs: monkeys in forest, humans in city • Important increase of cases recently • introduction of the vector and of the virus • decrease of vaccination spleen • rural exodus • abandon of moquito control programs
Cycle Aae Rm Asp Savanne Ville Forêt Aaf* H H H
Yellow Fever • 1 illness : 5-20 infected • 2 phases: acute viremic and toxic • 10-20% patients progress to toxic phase: • triad jaundice, hemorrhage, proteinuria • Mortality 15-20% of severe cases
Yellow fever: acute phase • Incubation: 3-6 days, sudden onset • To, myalgias (back), headache, chills, anorexia, No-Vo • Conjonctivitis, strawberry tongue • Possible early jaundice • Decrease of symptoms, probable resolution (>80% of cases)
Yellow fever: toxic phase • Remission < 24 hrs • Hepatic insufficiency : jaundice, dark urines • spontaneous bleeding (nose-mouth-GI), petechiae • coagulopathy, CIVD • encephalopathy • Renal failure : oliguria • Myocardial damage: • arrythmias, heart failure
Fever and CNS manifestations • Cerebral malaria (falciparum) • Meningococcal meningitis • Typhoid • Rickettsiae • Viral encephalitis (WNV, JE, ticks) • Rabies • African trypanosomiasis (tse-tse)
Fever and respiratory manifestations • Common pathogens • TB • Fever-pneumonia-hepatitis: Q fever • Helminths • Cough: malaria, typhoid, dengue…whatever!
Non Hemorragic Fever • Risks: country, zone, activities • Length of stay, date of return • Vaccination (hepatitis, yellow fever) • Prophylaxis • Symptoms there and treatment (partial?) • Pattern of fever: degree, periodicity
Typical Picture • Fever, malaise, headache • Chills, anorexia • Myalgias • Nausea, vomiting • Diarrhea DIAGNOSIS??
Non Hemorragic Fever Consider and Rule Out Malaria!
Fever: is it malaria? • If travel in malaria endemic zone • 35% malaria • 25% unknown source • 40% infectious cause or other non infectious • Falciparum: 90% onset of Sy < 1 month • Vivax: 50% onset Sy <1 month (2% >1 yr!)
Malaria Meningococcemia Dengue Hepatitis Amebiasis Shistosomiasis Filiariasis Typhoid Leishmaniasis Leptospirosis Non Hemorragic Fever
Non Specific Fevers • Meningococcemia: • extremely prevalent in certain african regions, frequent epidemics • Hepatitis: • endemic in all parts of the world: • serotype (A,B,C, E) depends on region travelled, activities: food washed with non treated water or not peeled, sexual contacts...
Dengue • Fever, myalgias, headache, retro- orbitalpain • Rash (transient), lymphadenopathy: 50% • Leukopenia, thrombocytppenia • Nausea, vomiting • Altered taste, skin hyperesthesia
Dengue-2 • Epidemics, seasonal variations • Transmission by mosquito bite : Aedes aegypti • Flavivirus: 4 serotypes --> immunity specific to the type • Crossed immunity : short, incomplete
Dengue-3: clinical syndromes • Non specific fever (especially kids) • Influenza syndrome : classic dengue • Hemorragic dengue (HD) • Dengue shock syndrome (DSS): high mortality
Dengue: 2 phases • Viral syndrome • The fever abates (3rd-5th day) • Apparition of the morbiliform rash • Possible development of hemorragic manifestations • Recrudescence of the fever
criteria: - spontaneous bleeding - plts < 100 000 - incr Hct >20% - ascites,pleural effusion - 20-30% of patients with DHF - mortality w/o Tx: 50%
Dengue • Diagnosis: • clinical especially in PVD • convalescent antibody titers • Treatment: supportive! • especially fluids, APAP • Vasopressors if needed • Intensive care for HD, DSS group • < 1% mortality if appropriate Tx for DH- DSS
Typhoid • Drinking or eating contaminated water/food • Salmonella typhi survives for long time in milieu • Most cases: imported: India, Philippines, South America • 1-4% of non-treated infected patients become chronic carriers
Typhoid - 2 • 10-20% transient diarrhea at onset • Sudden fever, increasing gradually • Persistence of fever 3-4 weeks • Abdo pain, constipation • Maculopapular rash (rose spots), coated tongue
Typhoid - complications • Intestinal perforation : 1-2% • Hemorrhage GI: 15% • Myocarditis: 1-5% • Cholecystitis: 1-2% • Septic arthritis, osteomyelitis, endocarditis, meningitis, abcess • Mortality: < 1% especially if Tx
Typhoid: Dx and Tx • Stool cultures : sensitivity 30-40% • Blood cultures: 50-70% • Duodenal sampling: 60-80% • Marrow aspiration : 80-95% • TMP SMX, ampicillin, PCeph3, fluoroquinolone • Steroids for patients in shock or coma
Leptospirosis • Swamp fever • Bacteria --> animals and humans • Exposure to water, soil, or food contaminated by urines of infected animals, via skin lesion or mucosae • Climate: temperate-tropical and North America
Leptospirosis - 2 phases • 1st, septicemic: viral illness, conjonctivitis; lasts 4-7 days • 2nd, immune: meningitis, ARF-hepatic, ARDS • icteric form : severe: hepatic necrosis, coagulopathy, hepatic dysfonction: Weil syndrome