Imported malaria in Spain (2009–2016): results from the +REDIVI Collaborative Network

Abstract

BackgroundImported malaria is a frequent diagnosis in travellers and migrants. The objective of this study was to describe the epidemiological and clinical characteristics of patients diagnosed with imported malaria within a Spanish collaborative network registering imported diseases (+REDIVI). In addition, the possible association between malaria and type of case, gender, age or area of exposure was explored.MethodsCases of imported malaria were identified among all cases registered in the +REDIVI database during the period October 2009–October 2016. Demographic, epidemiological and clinical characteristics were analysed.ResultsIn total, 11,816 cases of imported infectious diseases were registered in +REDIVI’s database between October 2009 and October 2016. Immigrants seen for the first time after migration accounted for 60.2% of cases, 21.0% of patients were travellers, and 18.8% were travellers/immigrants visiting friends and relatives (VFRs). There were 850 cases of malaria (850/11,816, 7.2%). Malaria was significantly more frequent in men than in women (56.8% vs 43.2%) and in VFR-immigrants (52.6%) as compared to travellers (21.3%), immigrants (20.7%) and VFR-travellers (5.4%) (p < 0.001). Although this data was not available for most patients with malaria, only a minority (29/217, 13.4%) mentioned correct anti-malarial prophylaxis. Sub-Saharan Africa was found to be the most common region of acquisition of malaria. Most common reason for consultation after travel was a febrile syndrome although an important proportion of immigrants were asymptomatic and presented only for health screening (27.3%). Around 5% of travellers presented with severe malaria. The most prevalent species of Plasmodium diagnosed was Plasmodium falciparum (81.5%). Malaria due to Plasmodium ovale/Plasmodium vivax was frequent among travellers (17%) and nearly 5% of all malaria cases in immigrants were caused by Plasmodium malariae.ConclusionsMalaria was among the five most frequent diagnoses registered in +REDIVI’s database. Some significant differences were found in the distribution of malaria according to gender, type of case, species. Among all malaria cases, the most frequent diagnosis was P. falciparum infection in VFR-immigrant men.

Epidemiologic Trends in Malaria Incidence Among Travelers Returning to Metropolitan France, 1996-2016

“… 29 , 30 , 31 Other studies, however, reported an increase of imported malaria incidence, gradually in Spain or the United States and more sharply in recent years in the Netherlands and Germany. 22 , 32 , 33 , 34 The rising number of cases was attributed to the increase in the number of travelers toward endemic areas or to population migrations for economic or political reasons (refugees). The balance between these different mechanisms may explain the complexity of the temporal patterns observed in several countries with imported malaria.…”

“…This elevation could be related to the increase in age of traveers, as observed in the United Kingdom and United States. 34,40,42 The reduction of malaria immunity in Africans living in France may have played a role; however, there is a lack of data about this variable. 43 Considering the higher incidence of severe cases, the concomitant stability in the number and proportion of deaths is surprising.…”

Prospective comparative multi-centre study on imported Plasmodium ovale wallikeri and Plasmodium ovale curtisi infections

“…used an effective prophylaxis [ 27 ]. Moreover, in a recent Spanish study considering only the subgroup of travellers with P. ovale / P. vivax malaria, these patients had also taken chemoprophylaxis significantly more frequently than those with non- P. ovale / P. vivax malaria (35.5% vs. 2.7%) [ 28 ]. These results reinforce the idea that current prophylaxis does not adequately act on P. ovale spp.…”

Spatiotemporal Distribution of Malaria in Spain in a Global Change Context

“…Most studies have identified Plasmodium falciparum as the predominant species responsible for imported malaria, not only in Spain [20,54,55], but also in other countries such as the United States [56], the United Kingdom [57] and France [58]. It must be taken into account that not many of these travellers and immigrants carry out correct anti-malarial prophylaxis [59], so informing people of the need to take appropriate preventive measures before travelling to endemic countries is essential.…”

“…Other countries, such as France, Italy and the United Kingdom, have also seen a greater number of imported malaria cases from former colonies with which they have historical and economic ties [55,56]. Among international travellers, some cases are also associated with travel to Latin America and Asia [57].…”