TY - JOUR
T1 - Malaria in long-term travelers
T2 - Infection risks and adherence to preventive measures – A prospective cohort study
AU - Suryapranata, Franciska S. T.
AU - Overbosch, Femke W.
AU - Matser, Amy
AU - Grobusch, Martin P.
AU - McCall, Matthew B. B.
AU - van Rijckevorsel, Gini G. C.
AU - Prins, Maria
AU - Sonder, Gerard J. B.
N1 - Funding Information: This study was conducted within the Amsterdam Academic Collaborative Center on Public Health, a collaboration between the Public Health Service of Amsterdam and the Academic Medical Center of the University of Amsterdam, the Netherlands. The Collaborative Center is financially supported by the Netherlands Organization for Health Research and Development (ZonMW; grant number 12501 0001) to G.J.B.Sonder. The study was funded by the Public Health Service Amsterdam, the Netherlands. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Funding Information: This study was conducted within the Amsterdam Academic Collaborative Center on Public Health, a collaboration between the Public Health Service of Amsterdam and the Academic Medical Center of the University of Amsterdam, the Netherlands. The Collaborative Center is financially supported by the Netherlands Organization for Health Research and Development (ZonMW; grant number 12501 0001 ) to G.J.B.Sonder. The study was funded by the Public Health Service Amsterdam, the Netherlands . The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Publisher Copyright: © 2022
PY - 2022/9/1
Y1 - 2022/9/1
N2 - Background: Chemoprophylaxis and anti-mosquito measures are key to preventing malaria in travelers. Long-term travelers are at higher risk than short-term travelers, but their adherence to preventive measures is lower. Our aim was to determine malaria exposure risks and predictors for adherence to malaria-preventive measures in long-term travelers. Methods: Long-term travelers (>12 weeks) completed a weekly questionnaire about preventive measures, symptoms, and malaria treatment abroad. Blood samples were tested for seroconversion to Plasmodium falciparum anti-circumsporozoite (PfCSP) antibody. Adherence to preventive measures was defined as number of weeks of their usage divided by number of weeks in malaria-endemic areas. Results: Of 561 travelers, the median travel time was 20 weeks (IQR 16–25). Eighteen were treated for malaria, all in sub-Saharan Africa. Sixteen PfCSP seroconversions were found, of whom only 3 had traveled to high-endemic areas. Of the 18 travelers treated for malaria, only one seroconverted. No associations were found between covariates and seroconversion. Neither treatment abroad nor seroconversion were reliable predictors for exposure. ‘Full adherence’ to chemoprophylaxis was reported by 52% (218/417) and was associated with travel to Africa, use of mefloquine, lack of prior travel history, shorter duration of travel, and use of DEET. Conclusions: The risk of malaria in this long-term travelers cohort was low. Our data confirm that anti-PfCSP seroconversion is not a reliable method to retrospectively identify incident infection, or probably exposure. Prevention efforts should focus on more experienced travellers and longer travel duration, for whom mefloquine should be considered as the first-choice chemoprophylaxis.
AB - Background: Chemoprophylaxis and anti-mosquito measures are key to preventing malaria in travelers. Long-term travelers are at higher risk than short-term travelers, but their adherence to preventive measures is lower. Our aim was to determine malaria exposure risks and predictors for adherence to malaria-preventive measures in long-term travelers. Methods: Long-term travelers (>12 weeks) completed a weekly questionnaire about preventive measures, symptoms, and malaria treatment abroad. Blood samples were tested for seroconversion to Plasmodium falciparum anti-circumsporozoite (PfCSP) antibody. Adherence to preventive measures was defined as number of weeks of their usage divided by number of weeks in malaria-endemic areas. Results: Of 561 travelers, the median travel time was 20 weeks (IQR 16–25). Eighteen were treated for malaria, all in sub-Saharan Africa. Sixteen PfCSP seroconversions were found, of whom only 3 had traveled to high-endemic areas. Of the 18 travelers treated for malaria, only one seroconverted. No associations were found between covariates and seroconversion. Neither treatment abroad nor seroconversion were reliable predictors for exposure. ‘Full adherence’ to chemoprophylaxis was reported by 52% (218/417) and was associated with travel to Africa, use of mefloquine, lack of prior travel history, shorter duration of travel, and use of DEET. Conclusions: The risk of malaria in this long-term travelers cohort was low. Our data confirm that anti-PfCSP seroconversion is not a reliable method to retrospectively identify incident infection, or probably exposure. Prevention efforts should focus on more experienced travellers and longer travel duration, for whom mefloquine should be considered as the first-choice chemoprophylaxis.
UR - http://www.scopus.com/inward/record.url?scp=85135695868&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.tmaid.2022.102406
DO - https://doi.org/10.1016/j.tmaid.2022.102406
M3 - Article
C2 - 35934313
SN - 1477-8939
VL - 49
JO - Travel medicine and infectious disease
JF - Travel medicine and infectious disease
M1 - 102406
ER -