Travellers' malaria - 'one shoe does not fit all'

Travellers' malaria is an exciting topic. It is a field in flux with evolving options for chemoprophylaxis, self-diagnosis, self-treatment, risk/strategy analyses and surveillance. Ideologies vary and experts differ but debate is needed and can bring change. The launch of a new thematic series in the Malaria Journal -- " Travellers' malaria " -- creates an ideal forum to bring together research papers, reviews, opinion papers and commentaries, and will hopefully stimulate debate

In for the long-haul? Seropositivity and sequelae 1 year post COVID-19.

Health care workers (HCW) who have been on the front-line of the pandemic, highly exposed to SARS-CoV-2 and frequently infected, are now the focus of research on the longer-term evolution of COVID-19. This is important as HCWs are generally young, previously healthy adults and are representative of the active “workforce” in countries worldwide. An infection with SARS-CoV-2 can be seen as a twin-edged sword: on one hand, having had the infection will confer some immunity or protection against re-infection whilst on the other hand, infection sequelae may result in subtle or significant health consequences. How long will the infection -conferred, antibody reactivity to the receptor-binding domain of SARS-CoV-2, the neutralising activity and the specific memory B cells last post infection? Mounting evidence suggests that this protection may last for 12 months or longer [1]. What is the price of this COVID armour? The cost is steep! SARS-CoV-2 infected individuals may experience debilitating sequelae that persist for months and longer. A systematic review on long-term sequelae in previously healthy, young people aged < 50 years old found a broad spectrum of symptoms [2]. These included persistent fatigue, breathlessness, diminished quality of life, impaired pulmonary function, myocarditis, neurological and psychiatric diagnoses, slow and stagnant recovery of olfactory and gustatory function. Due to the global proliferation of COVID-19 infection, the burden of sequelae is thus projected to be immense

Deaths caused by malaria in Switzerland 1988-2002

Despite sophisticated intensive medicine, between one and three malaria-associated deaths occur annually in Switzerland. In this retrospective study, 33 deaths (25 men and 8 women) caused by falciparum malaria reported in Switzerland from 1988 to 2002 were analyzed. The case fatality ratio (CFR) for the falciparum infections for the 15-year period was 1.2%, with a peak of 2.2% in 1991. Sub-Saharan Africa was the source of all the imported fatal infections. Non-immune Europeans had a significantly higher case fatality ratio than the non-Europeans (1.7% versus 0.2%; P < 0.001). Careless use or non-use of prophylaxis, sometimes because of physicians giving unsatisfactory pre-travel advice, and initially missed diagnosis post-travel were factors that contributed to the development of severe infections leading to death. Travelers should be sensitized to the risk of malaria by well-informed general practitioners. Updated information is readily available (www.safetravel.ch). Regarding diagnosis and treatment, greater physician awareness of the disease is needed, and expert advice should be sought without hesitation. Rapid malaria tests may be a useful diagnostic adjunct in centers where microscopic expertise is lacking. Falciparum malaria in a non-immune patient is an emergency requiring immediate treatment

Imported malaria in Switzerland, (1990–2019): A retrospective analysis

BACKGROUND Malaria is a life-threatening, mosquito-borne parasitic disease, caused by Plasmodium spp. It is a major public health issue. Malaria in Switzerland is primarily "imported" by infected international travellers, migrants, and asylum-seekers. METHOD We investigated the epidemiology and characteristics of imported malaria in Switzerland in the period between 1990 and 2019 using data from the Swiss Federal Office of Public Health (BAG). We also obtained traveller statistics from the World Tourism Organization (UNWTO). RESULTS During the last thirty years a total of 8'439 malaria cases and 52 deaths were reported in Switzerland. The main origin of infection was West Africa, followed by Central Africa and East Africa. The profile of malaria in migrants in Switzerland has changed, reflecting variation in migrant flows. The estimated risk of malaria in travellers sank significantly over the time frame of the study (p < 0.001, 95% CI -0.076 to -0.043). CONCLUSIONS Travel medicine should focus on West Africa, the main source of malaria in Switzerland. Despite most cases and all but one death being caused by Plasmodium falciparum, Plasmodium vivax remains a threat for travellers and is associated with complex prevention and therapy regimens. Public health authorities need to pre-empt the need for malaria screening, prevention and treatment based on the profile of migrant waves from malaria endemic areas including Eritrea and Afghanistan arriving in Europe

Hair concentrations of anti-malarials in returned travellers-the HAIR study: Proof of principle analysis

Background: Hair analysis to identify substance use is an established methodology. This could also be a method to monitor adherence to antimalarial drugs. We aimed to establish a methodology to determine hair concentrations of atovaquone, proguanil and mefloquine in travellers using chemoprophylaxis. Methods: A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for simultaneous analysis of the antimalarial drugs -atovaquone (ATQ), proguanil (PRO) and mefloquine (MQ), in human hair. The hair samples from five volunteers were used for this proof-of-concept analysis. Three volunteers were taking daily atovaquone/proguanil (ATQ/PRO) chemoprophylaxis and two volunteers were using weekly mefloquine (MQ) chemoprophylaxis. Results: With this proof-of-principle analysis, we could show that ATQ/PRO and MQ are integrated into the hair matrix. Chemoprophylaxis could be quantified with the established method. In hair segments, maximal concentrations of 3.0 ng/mL/20 mg hair proguanil, 1.3 ng/mL/20 mg hair atovaquone and 78.3 ng/mL/20 mg hair mefloquine were measured. Moreover, malaria drug concentration changes correlated with the time interval since finishing the chemoprophylaxis regimen. Conclusions: The validated method was used successfully for the analysis of antimalarial-drug positive hair samples containing atovaquone, proguanil or mefloquine. This research shows that hair can be used for adherence monitoring of chemoprophylaxis and paves the way for larger studies and optimized procedures

Current Challenges in Travelers' Malaria

Travel health providers are often confronted with complex scenarios when advising travelers on malaria prevention. Current challenges in prevention include malaria risk assessment, where a detailed itinerary and knowledge of malaria epidemiology are needed. Up-to-date information on the correct use, limitations, and drug interactions of current priority chemoprophylaxis agents (atovaquone/proguanil, mefloquine, doxycycline) is key. Another challenge is to identify and reach travelers who are most at risk of malaria, such as the traveler visiting friends and relatives. Posttravel, delays in presentation, diagnosis, and inappropriate treatment of malaria are key risk factors leading to death. Treatment of malaria is an emergency requiring expert in-patient management and referral to a center with adequate expertise. Artemisinin combination therapies are the drugs of choice for uncomplicated malaria. Complicated malaria is treated preferably with intravenous artesunate, and the supply and quality of this life-saving antimalarial in some settings can pose one of the most urgent challenges in travelers' malari

Imported Infectious Disease and Purpose of Travel, Switzerland

Travelers who visited friends or relatives were more likely to receive a diagnosis of malaria or viral hepatitis than those who traveled for other reasons

Use of mefloquine in children - a review of dosage, pharmacokinetics and tolerability data

Currently available data provide a scientific basis for the use of mefloquine in small children in the chemoprophylaxis setting and as a part of treatment regimens for children living in endemic areas