Open Access | Modeling the risk of malaria for travellers to areas with stable malaria transmission

Background
Malaria is an important threat to travellers visiting endemic regions. The risk of acquiring malaria is complex and a number of factors including transmission intensity, duration of exposure, season of the year and use of chemoprophylaxis have to be taken into account estimating risk.
 
Methods
A mathematical model was developed to estimate the risk of non-immune individual acquiring falciparum malaria when traveling to the Amazon region of Brazil. The risk of malaria infection to travellers was calculated as a function of duration of exposure and season of arrival.
 
Results
The results suggest significant variation of risk for non-immune travellers depending on arrival season, duration of the visit and transmission intensity. The calculated risk for visitors staying longer than four months during peak transmission was 0.5% per visit.
 
Conclusions
Risk estimates based on mathematical modeling based on accurate data can be a valuable tool in assessing risk/benefits and cost/benefits when deciding on the value of interventions for travellers to malaria endemic regions.