Emerging Infectious Diseases Journal

Highlights: Emerging Infectious Diseases, Vol. 19, No. 7 (July 2013)

1. Travel-associated Illness Trends and Clusters, 2000–2010

The illnesses that international travelers pick up during their travels may provide a snapshot of disease trends around the world; and also, can indicate which diseases travelers need to take steps to prevent.  An international study analyzed data from more than 42,000 returned travelers who visited 18 travel health clinics worldwide between 2000 and 2010 to better understand disease trends. Researchers found that travelers who presented for post-travel care increasingly had visited developing regions, which may drive increases in ill travelers returning home. The most common destinations from which ill travelers returned were sub-Saharan Africa, Southeast Asia, South Central Asia and South America, with a substantial increase in proportion detected among those returning from South Central Asia. The clinics, part of the GeoSentinel surveillance network, reported significant increases in ill travelers returning with enteric fever (typhoid or paratyphoid) and dengue. At the same time, they observed a significant decrease in malaria, which may in part be due to better tolerated malaria preventative drugs. These data can help guide physicians and travel health experts caring for travelers presenting with illness and as they counsel travelers about steps travelers should take to protect themselves from disease while traveling internationally.

Contact:
Karin Leder
Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University
Melbourne, Australia
karin.leder@monash.edu                

2. Influence of Humans on Evolution and Mobilization of Environmental Antibiotic Resistome

Disease-causing germs are increasingly resistant to multiple antibiotics, a situation that makes it difficult to treat some serious infections. How germs develop drug resistance has long been a mystery, however a growing body of evidence points to genetic material from environmental bacteria as the source.  This “environmental antibiotic resistome” is ancient, mobile, and linked to human activity such as the use of manures, water treatments, heavy metals and other agriculture and industrial chemicals (biocides). A results of 3-day workshop in this area calls for more research into understanding the impacts of human activities on the environmental resistance and its effects on the dissemination of antibiotic resistance and ultimately public health. Specifically, the authors point out a number of knowledge gaps including the need to understand the roles of various pollutants and biocides and their mixtures on antibiotic resistance selection and mobilization, which environments promote this gene transfer, and a catalogue to the genetic diversity of resistance in the environment that can ultimately be tapped for movement into pathogens.

Contact:
Gerald Wright
McMaster University, Ontario, Canada
wrightge@mcmaster.ca

3. Pneumococcal Serotypes before and after Introduction of Conjugate Vaccines, United States, 1999–2011

There are 93 known serotypes of Streptococcus pneumoniae, (sometimes called strep), a bacteria that causes more than 39,000 cases of pneumonia and other serious infectious disease and 4,000 deaths in the United States each year. Introduction of the pneumococcal conjugate vaccine (PCV7), which provided protection against 7 of the 93 serotypes, in 2000 led to reductions in the incidence of serious life-threatening strep infections. The percentage of cases caused by some of the other serotypes not included in the PCV7 vaccine, particularly 19A, increased. A second vaccine (PCV13) with six additional serotypes (1, 3, 5, 6A, 7F, 19A) was introduced in March 2010. Researchers found that the prevalence of PCV7 serotypes decreased from 64 percent of invasive and 50 percent of noninvasive isolates in 1999-2000 to 3.8 percent and 4.2 percent in 2010-11. The increases in infections caused by serotype 19A stopped after introduction of the new PCV13 vaccine.

Contact:
Sandra Richter, MD, D (ABMM)
Clinical and Molecular Microbiology
Department of Clinical Pathology
Cleveland Clinic
Cleveland, OH
(216) 444-6519
richtes@ccf.org

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U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES