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Updated: May 7, 2026

An In Vitro Model for Measuring Immune Responses to Malaria in the Context of HIV Co-infection
Published on: October 6, 2015
Dengue fever, tuberculosis, human immunodeficiency virus, and hepatitis C virus conversion in a group of long-term
Jenny T Visser1, Ciaran A Edwards
1Department of Primary Health Care and General Practice, University of Otago, Wellington, New Zealand.
Background:
Development and humanitarian aid workers are a diverse group of travelers who, because of the nature of their travel, may have specific travel-related health risks. The main objective of this study was to quantify the risk of dengue fever virus (DFV), tuberculosis (TB), human immunodeficiency virus (HIV), and hepatitis C virus (HCV) infections in a group of long-term development aid volunteers.
Methods:
Medical files of Volunteer Service Abroad (VSA) volunteers and their accompanying family/partner/spouse serving over 17 years (1995-2011) were reviewed. Demographics, destination, months spent in-country, and, where available, results of pre- and post-assignment testing for DFV, TB, HCV and HIV infections were extracted.
Results:
Results from 652 assignments were audited. Conversion rates were calculated when both pre- and post-assignment results were available. Evidence of dengue fever seroconversion was found in 6.3% of 205 volunteers [at a rate of 3.4 per 1,000 person months (pm) on assignment], with assignments in Southeast Asia having the highest risk. Evidence of TB during assignment was found in 2.9% of 336 volunteers converting at a rate of 1.4 per 1,000 pm. There were no HIV or HCV infections detected. On post-assignment questioning, 6.7% of volunteers reported unprotected sex with someone other than their regular partner and 9.8% reported a potential exposure to blood and/or blood products.
Conclusions:
Infection with DFV and TB occurred in this group at rates similar to that seen in other groups of long-term travelers, and screening would appear to be warranted. While none contracted HIV or HCV infection, reported behavior did put them at risk of blood- and body fluid-borne diseases. It is important that pre-assignment travel health preparation in this group focuses on strategies to minimize these risks.
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