Malaria in numbers.
There were an estimated 228 million malaria cases worldwide in 2018, resulting in an estimated 405,000 deaths. Approximately 93% of all malaria cases and 94% of all malaria deaths occurred in the African region, and the majority of deaths were due to Plasmodium falciparum infection.1 In Catalonia alone, there were 200 reported cases in 2017.2
The malaria vaccine.
News of various COVID -19 vaccines was rightly celebrated over the past year. However, the news of a malaria vaccine was not as widely reported despite it also being ground-breaking. Trials of the malaria vaccine predate the COVID pandemic. Professor Hill, who worked on the Astra Zeneca vaccine with the Oxford team, explained that this was developed on the strength of research into malaria.3 That this parasite which has numerous immune evasive mechanisms, is now subject to a vaccine with an efficacy of 77% is truly positive.4 BioNTech are looking at a malaria vaccine and hope to start clinical trials for the first mRNA-based vaccine by the end of 2022.5
As of October 2021, the malaria vaccine is now being recommended by the WHO for all at-risk children.6 When you take into account that malaria remains the primary cause of death and disease in children in Sub-Saharan Africa, it translates into a real hope.6 Proved to have a good safety profile, the cost-effective nature of the intervention will surely be a great motivator for rolling out malaria immunisation programs as soon as possible.6
Malaria as a pal through the ages.
Malaria has been a constant companion or pal through the ages, not only in Africa but also closer to home. Catalan grandparents talking of tertian fevers were referring to malaria, although many non-medics may not have realised this at the time.7 The aiguamolls or marshes of the Alt and Baixa Emporda were important rice fields. Even in the 18th century, the rice fields and their role in local malaria were controversial. Popular culture reflected this with a saying which went as follows: “Mothers who have daughters; if you do not love them enough, marry them to Albons or Bellcaire; and if you want them dead soon; marry them to Vilademat.”8 Climate change and instability were also being cited as a reason for the increase in malaria due to the accumulated stagnant water.9 Also, nothing new, economic interests were opposed to health concerns as the increased rice, and other harvests were welcome to some.9 The cyclical natures of both the duration of the fevers and the season of the year were documented by the doctors of the time, such as Francisco Pons. Dr Pons also documented that local administrations were draining the marshlands where these malarian fevers were present.9 Treatment for the fevers was varied and included bleeding, making people vomit and all sorts of other ineffective and miserable solutions.9 The town of Pals to this day continues to cultivate rice.
Further afield, in Tuscany in Italy, DH Lawrence describes seeing malaria in the locals. Whilst writing Lady Chatterley’s Lover, DH Lawrence also wrote “Etruscan Places”, detailing the marvels of the Etruscan tombs in Tarquinia, among other places. Written in 1926, he “asked Luigi, our driver if he had any fever. At first, he too said no. Then he admitted he had had a touch now and then. Which was evident, for his face was small and yellowish, evidently the thing had eaten into him.”10
How this can impact you as a non-infectious diseases specialist.
Firstly, the most important aspect is to think of malaria. Although cases of malaria in Catalonia are imported, people may not think to mention a resort holiday in the sun to a place they may not associate with malaria. Embarrassment at not having taken prophylaxis may also lead to people being reluctant to help you think of malaria as a possibility. Or they may have simply forgotten about a business trip 18 months ago.11 For Muslim pilgrims, unless the hajj is undertaken in a single day in an air-conditioned car, malaria is a risk about which they may not have thought. Especially as current recommendations are for no chemoprophylaxis for the hajj but to still keep strict mosquito bite prevention measures.12 The symptoms themselves are non-specific. Fevers, sweats, headaches and myalgia are common complaints, and malaria needs to be on the list of differentials.13 Older patients are especially at risk of worse outcomes if malaria is not diagnosed in a timely fashion.14 If you practise in Catalonia, there is an epidemiological form which you need to fill in.15
As a traveller.
Over the past twenty to thirty years, flying in less than a day to places that previously would have taken days, if not weeks, has become widespread. Great explorers such as Shackleton or Thesiger and, more recently, Fiennes or Monty Python member Palin, spent months preparing their travels. Medical supplies did not always include chemical prophylaxis but did include antimosquito measures such as nets which are still relevant. Choice of antimalaria prophylaxis is specialised, but the CDC offers a good summary.16 Electronic buzzers have not been shown to be effective in this setting.17 Insecticide-treated clothing or netting are probably beneficial with the caveat that in children and pregnant women, the risk-benefit must be revised.18 In non-immune travellers, the possibilities of acquiring malaria after a single bite can be as high as 44%.18
So, the future in malaria prevention is positive, and hopefully it will become, eventually, a historical disease.
References.
1. World Health Organisation. World malaria report 2019. (2019).
2. Idescat. Anuario estadístico de Cataluña. Enfermedades de declaración obligatoria individualizada. Casos. Por sexo y grupos de edad. https://www.idescat.cat/pub/?id=aec&n=814&lang=es.
3. Malaria vaccine hailed as potential breakthrough – BBC News. https://www.bbc.com/news/health-56858158.
4. Datoo, M. S. et al. High Efficacy of a Low Dose Candidate Malaria Vaccine, R21 in 1 Adjuvant Matrix-MTM, with Seasonal Administration to Children in Burkina Faso. SSRN Electronic Journal (2021) doi:10.2139/SSRN.3830681.
5. BioNTech. BioNTech Provides Update on Plans to Develop Sustainable Solutions to Address Infectious Diseases on the African Continent. https://investors.biontech.de/node/10366/pdf (2021).
6. WHO recommends groundbreaking malaria vaccine for children at risk. https://www.who.int/news/item/06-10-2021-who-recommends-groundbreaking-malaria-vaccine-for-children-at-risk.
7. Torrent Quer, N. Cartografia, pràctiques mèdiques i respostes socials a l’entorn del paludisme: Catalunya, segle XIX. TDX (Tesis Doctorals en Xarxa) (2017).
8. Barret, F. Els Aiguamolls and Malaria. http://www.iberianature.com/material/aiguamollsmalaria.html.
9. Benítez, K. P. & Benítez, K. A. P. Fiebres, arroz e insalubridad: el caso del Ampurdán (1783-1787). Revista de Historia Moderna 0, 221–254 (2020).
10. Lawrence, D. Etruscan Places: Travels Through Forgotten Italy . (1932).
11. Simon, C. et al. Oxford Handbook of General Practice. Oxford Handbook of General Practice (2020) doi:10.1093/MED/9780198808183.001.0001.
12. NHS. Saudi Arabia Malaria Map – Fit for Travel. https://www.fitfortravel.nhs.uk/destinations/middle-east/saudi-arabia/saudi-arabia-malaria-map.
13. Malaria infection – Symptoms, diagnosis and treatment | BMJ Best Practice US. https://bestpractice.bmj.com/topics/en-us/161.
14. Allen, N., Bergin, C. & Kennelly, S. P. Malaria in the returning older traveler. Tropical Diseases, Travel Medicine and Vaccines 2, 1–5 (2015).
15. Gencat. Malària. Canal Salut. https://canalsalut.gencat.cat/ca/detalls/article/Malaria#bloc6.
16. Prevention, C.-C. for D. C. and. CDC – Malaria – Travelers – Choosing a Drug to Prevent Malaria. (2019).
17. Malaria – Prevention – NHS. https://www.nhs.uk/conditions/malaria/prevention/.
18. Croft, A. M. Malaria: prevention in travellers (non-drug interventions). BMJ Clinical Evidence 2014, (2014).
Dr Alice Byram 