Clinical assessment: Diagnosis is made by blood culture Stool cultures are positive in approximately 30% of bacteremic patients Bone marrow cultures may be useful because they remain positive long after treatment has been initiated and are more sensitive than blood culture Serology is not recommended as it often cross-reacts with other Salmonella serotypes Management: Empiric management of children with suspected typhoid is reviewed in e-Table 94.18 Historically, fluoroquinolones have been the treatment of choice However, the recent evolution and recognition of multidrug-resistant Salmonella isolates has complicated empiric therapy In general, fluoroquinolones should not be first-line therapy if typhoid fever in patient from South Asia or other regions where there is a known increase in resistance to fluoroquinolones For travelers to this area, use of third-generation cephalosporins and high-dose azithromycin (1 g) is recommended Bacteremia should be treated for a total 7- to 10-day total course, with transition from parenteral to oral therapy after bacteremia has cleared and antibiotic susceptibilities are available In some sub-Saharan African nations, up to 40% of Salmonella isolates are cephalosporin In patients with severe systemic illness, such as typhoid-associated shock or encephalopathy, dexamethasone (3 mg/kg followed by mg/kg every hours for 48 hours), should be considered The chronic carrier state can be eradicated by weeks of oral fluoroquinolones Contact and standard precautions should be used for providers caring for children with suspected typhoid fever Dengue CLINICAL PEARLS AND PITFALLS Dengue is the most prevalent mosquito-transmitted viral illness and should be considered in the differential diagnosis of any febrile patient presenting in the ED within weeks of return from a tropical or subtropical region Clinical manifestations include self-limited dengue fever to life-threatening dengue hemorrhagic fever with shock syndrome Treatment is with supportive care and fluid resuscitation, including blood transfusion Current Evidence Dengue is transmitted by the Aedes aegypti mosquitoes, which are most active during the day, but can bite at any time of day or night The disease is endemic to central and South America, sub-Saharan Africa, the Indian subcontinent, and Southeast Asia Recently there has been a broadening of the geographic distribution of the disease In the last decade, outbreaks have been reported in Texas, Florida, and Hawaii, and the mosquito vector already is widespread throughout the southern United States The worldwide incidence has been increasing in the past several decades due to a number of factors including population growth, overcrowded urban living with poor sanitation, increasingly mobile/transient population and therefore increased mobility of the mosquitoes, virus and infected individuals, and lack of effective mosquito control Each year there are an estimated 50 to 100 million dengue infections, with >500,000 cases of dengue hemorrhagic fever, and >22,000 deaths, primarily in children Goals of Treatment The goal of dengue management is to identify which children are at risk for dengue based on travel history and for the PEM clinician to be aware that rapid fluid shifts after fluid resuscitation can lead to volume overload Clinical Considerations Clinical recognition: The differential diagnosis includes febrile illness with similar clinical manifestations such as influenza, enteroviral infection, measles, and rubella The diagnosis is typically a clinical one when treating patients with recent travel to dengue endemic regions Only 50% of patients infected with dengue develop symptoms Clinical manifestations range from self-limited dengue fever to dengue hemorrhagic with shock syndrome Symptoms typically develop within to 14 days after the bite of an infected mosquito; the risk of severe disease is much higher in sequential infections In 2009, the World Health Organization (WHO) published revised dengue case definitions ( e-Table 94.19 ) Three distinct phases exist The first is the febrile phase Here, children develop pyrexia (or hyperpyrexia), vomiting, joint pain Some develop a transient maculopapular rash, lasting approximately to days Most patients not progress to the next phase and improve without