ReviewMalaria prevention in the pregnant traveller: A review
Introduction
In 2011 more than 100 million tourists travelled to malaria-endemic countries [1]. Pregnant women travelling to malaria-endemic areas usually fall into one of the following categories: Women seeking pre-travel advise for tourist travel, sometimes explicitly planning to get pregnant at the tropical destination (tourist traveller), women with their entire family destined to stay in malarious areas on longer term contracts/for professional purposes, already pregnant or planning pregnancy during a long-term stay (expatriate traveller) as well as migrant women needing to visit friends and relatives in their country of origin in order to attend important reunions/festivities with their family despite being pregnant (visiting friends and relatives, VFR traveller). Thus, health experts involved in travel medicine are frequently confronted with questions around malaria prevention during pregnancy.
Section snippets
Malaria and pregnancy
Malaria infection during pregnancy poses a serious risk for the mother and the unborn child [2], [3]. The interaction of malaria and pregnancy is complex and not yet fully understood [4], [5]. Malaria parasites adhere in the vascular system of the placenta which leads to impairment of the (micro) circulation and eventually placental insufficiency [4]. A relationship between concurrent malaria infection and abnormal uterine blood flow has been demonstrated [4].
Semi-immunity to malaria is of
Anti-mosquito measures
In Sub-Saharan Africa and in particular during the rainy season, the average transmission risk exceeds one infectious mosquito bite per person per day. Anti-mosquito measures aim to reduce infectious mosquito bites. Interestingly, it has been shown in rural Gambia that pregnant women attract twice as many Anopheles gambiae complex mosquitoes as their non-pregnant counterparts, probably due to physiological and behavioural changes [8]. This finding underlines the importance of protective
Mefloquine
Plasmodium species causing malaria are sensitive to mefloquine but resistance to mefloquine exists especially in Thailand and borders to neighbouring countries [18].
Next to chloroquine (see below) and compared to other commonly used anti-malarials in travellers, mefloquine is certainly the drug with most data available on safety in pregnancy. Regarding embryotoxicity, animal studies only proved a teratogenic effect of mefloquine if the dose several fold exceeded the dose recommended for
International recommendations
First, it should be emphasised that the German Society for Tropical Medicine and International Health (DTG), the National Travel Health Network and Centre (NaTHNaC), the Centers for disease Control and Prevention (CDC) and the World Health Organisation (WHO) strongly recommend pregnant women to avoid travelling to malaria endemic regions [30], [31], [32]. If travelling to malaria-endemic areas cannot be avoided or postponed, consequent malaria prophylaxis including avoidance of mosquito bites
Risk assessment and recommendations
Travel medicine guidelines in general do not recommend travelling to malarious areas while being pregnant (see previous paragraph). Yet, the likelihood of acquiring malaria (=risk), the motivation for travelling (benefit) as well as the risk perception related to both, malaria disease and safety/tolerability aspects related to prophylactic (both chemoprophylaxis as well as repellents) may vary among the different groups of pregnant women travellers i) tourist traveller, ii) expatriate and iii)
Conclusion
Risk assessment taking into account risks, benefits as well as individual risk perception should be based on the reason/motivation for travelling to malaria-endemic areas which will be different in tourist-, expatriate- or VFR-travellers. If possible, pregnant women should be advised to avoid or postpone travelling to regions were malaria is endemic. If travelling is inevitable for the pregnant woman for whatever reason, effective malaria prevention measures should be used consequently.
There
Conflict of interest
Jakob P. Cramer participates as investigator in the pregnancy registry initiated by Sigma Tau.
Louise Roggelin has no conflict of interest to declare.
Funding
None.
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2015, Wilderness and Environmental MedicineCitation Excerpt :Mefloquine is the drug of choice for prophylaxis and therapy in pregnant women. If going to an area of high Mefloquine resistance, either Atovaquone-Proguanil or Artemether-Lumefantrine can be used.78 There is no good data on the safety of anti- malarials during the first trimester of pregnancy.78
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2015, Travel Medicine and Infectious DiseaseCitation Excerpt :The use of insecticide-treated bed nets and the application of DEET-repellents are considered safe and should be recommended to all pregnant travellers visiting malaria-endemic areas as well as protective clothing and air-conditioned or screened sleeping areas [20,39]. It should be noted that no studies exist on the use of DEET in women in the first trimester, or on the use of other repellents such as Icaridin or IR3535 in pregnancy [40], but based on experience, DEET is recommended by experts even in the first trimester [9,10]. A total of 50 treatment regimens were reported in our analysis.
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2019, Travel Medicine and Infectious DiseaseCitation Excerpt :More likely it is due to a lack of confidence or need for reassurance particularly due to the higher risk of malaria, or of severe complications from malaria in these groups. In the case of pregnancy this is likely to be compounded by the limited data on medication safety and maternal and foetal outcomes [13]. Other commonly queried special health needs included immune suppression, mental health conditions (anxiety and depression) and epilepsy.