Page 981 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

712 PART 5: Infectious Disorders

people from developed countries visit the developing world yearly, and of cases, respectively). Twenty-two percent of patients had an unspeci-
this number appears to be increasing. 2,3,10 In addition, preliminary data fied febrile illness that was not identified while febrile diarrheal disease
suggest that visitors and expatriates are expanding subpopulations with occurred in 15% of patients. Fever and respiratory infection were seen
increased risk for both injurious and infectious consequences of inter- in 14% of patients. Almost 70% of sick travelers at GeoSentinel sites had
national travel. 8,9,11 More recent estimates state that 8% of travelers to visited sub-Saharan Africa, Southeast Asia, the Caribbean, and Central
the developing world seek medical attention for infectious illness. 1,12-14 and South America. However, the rate of critical illness and death was
While the management of critical trauma and cardiovascular disease can not determined by these studies, and, in fact, may be falsely low given
be difficult, the varying exposures and subsequent infectious diseases the low rate of self-reporting among severely ill patients. 4,6,7
associated with critical illness present the most difficult cases for the Management of a febrile, critically ill traveler can be difficult, espe-
critical care practitioner. cially given the wide range of infectious agents that can cause disease.
This chapter offers an approach to the critically ill traveler, ranging Many of these entities, uncommon in the developed world, present
from a broad empiric evaluation and treatment strategy through com- without specific symptoms or signs and may not seem temporally
mon disease to subsequent public health protection and impact. related to travel itself. Rare and unusual diseases are becoming more
common, and their presenting symptoms and clinical patterns may be
THE IMPORTANCE OF THE CRITICALLY-ILL TRAVELER unfamiliar to health care providers in the developed world. In addition,
diagnosis often requires ancillary testing not available to all hospitals
The rate of illness after travel is unknown, but some self-reported rates and as a consequence may be delayed or require specialty public health
suggest 22% to 64% of travelers to developing countries suffer some sort laboratories. Finally, decisions concerning appropriate antimicrobial
of illness related to travel. GeoSentinel, the global surveillance network therapy as well as infection control measures are optimally made early
of the International Society of Travel Medicine and the Centers for in the course of the disease, often before clinical trajectory is known and
Disease Control and Prevention (CDC), publishes on travel-related ill- diagnostic information has returned.
ness by category and location. Sentinel data on ill travelers are collected However, only a few diseases and organisms need early recognition
at more than 40 GeoSentinel sites on six continents. In 2006, a clinical- and treatment. 4,6,7 Table 77-1 identifies the most common pathogens
based surveillance study on 17,353 ill travelers who returned from travel that cause illnesses in travelers, ranging from the common but self-
in developing countries was reported from 30 sites on 6 continents via limiting diarrhea through more rare but deadly sources of acute respi-
GeoSentinel. 4,6,7 The report covered June 1996 to August 2004. The ratory failure. Only a small number of these cases, however, are found
primary manifestations for approximately two-thirds of the returned within the ICU. Severe (including cerebral) malaria, meningococcal
travelers fell into five major syndrome categories: systemic febrile illness meningitis, dengue fever, viral hemorrhagic fevers (eg, Ebola, Marburg),
without localizing findings, acute diarrhea, dermatologic disorders, severe coronaviruses (SARS and MERS-CoV), influenza, plague, and
chronic diarrhea, and nondiarrheal gastrointestinal disorders. A later tularemia are lethal pathogens causing rapid multiorgan system failure
report from GeoSentinel specifically evaluated fever, which was the in a traveler. 4,6,7 Thus, despite the wide array of etiologic possibilities, a
reason for seeking care in 28% of almost 25,000 ill returning travelers systematic approach to evaluation and empiric therapy, with definitive
seen between 1997 and 2006. 4,6,7 The most common specific diagnoses diagnostics, will allow for an efficient, organized care plan for the travel-
among patients with fever were malaria and dengue fever (21% and 6% ing patient.

TABLE 77-1 Incidence Per Month of Pathogens Causing Severe Illness in Travelers. In Steffen et al 2008
100%
Travelers’ diarrhea
(ETEC >15% of total) 20–60%

10%

Malaria (no chemoprophylaxis west africa)
Influenza A or B
Dengue infection (symptomatic) 1%
Animal bite with rabies risk
PPD conversion
Malaria (with + without chemoprophylaxis tropical africa)
0.1%
Hepatitis A
Typhoid (South Asia, N/W/Central-Africa)

Tick-borne encephalitis (Rural Austria) 0.01%
Hepatitis B
Typhoid (other areas)
HIV-infection
Fatal accident 0.001%

Cholera
Legionella infection
Japanese encephalitis 0.0001%
Meningococcal disease
Poliomyelitis

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