Malaria is the most common disease among passengers travelling from Africa to Europa, but there are other diseases, including dengue and West Nile virus, according to a study published in the scientific journal Eurosurveillance.
Arthropod diseases are transmitted by the bite of infected arthropods, including ticks, mosquitoes, sandflies, or fleas. The Africa Centre for Disease Control and Prevention (Africa CDC) was established in 2017 to strengthen disease surveillance in Africa, but information regarding how many passengers carry these diseases out of Africa is still lacking.
In this study, the team assessed traveller’s health data collected in Europe between 2015 and 2019 as a way to provide actionable information for the Africa CDC. For the diseases with more than 100 cases per year, the authors also determined the disease-specific infection rate, which explains the rate of spread and infection.
The study looked at information from 125 million people travelling from Africa to Europe, mainly from Northern Africa (almost 80 million). Malaria was the most common disease found, affecting 34,235 passengers. Other mosquito-borne infections were less common, with 956 cases of dengue, 161 chikungunya, 16 Zika virus disease, nine West Nile fever infection, four Rift Valley fever, and one yellow fever. There were no cases of Crimean-Congo hemorrhagic fever, plague, or tick-borne encephalitis from Africa.
The high number of malaria cases “reflects the high level of endemicity of the disease and transmissibility of the parasites in a large part of the African continent, the long durations of detectable (untreated) infections (as compared with the arboviral diseases) and the high proportion of cases presenting clinical manifestation making diagnosis likely,” the authors write in the paper. While the team acknowledges limitations in their study — such as underestimation of cases given that not all are reported after passengers return to Europe — they still believe that “travellers health data can efficiently complement local surveillance data, particularly when the country or region has a sub-optimal surveillance system. Similarly, travellers might be index cases of yet unrecognised outbreaks.”
Gossner Céline M, Hallmaier-Wacker Luisa, Briet Olivier, Haussig Joana M, de Valk Henriette, Wijermans Ariana, Bakonyi Tamas, Madubuko Theresa, Frank Christina, Noel Harold, Abdulaziz Mohammed. Arthropod-borne diseases among travellers arriving in Europe from Africa, 2015 to 2019. Euro Surveill. 2023;28(7):pii=2200270. Available from: https://doi.org/10.2807/1560-7917.ES.2023.28.7.2200270