Malaria prophylaxis

Malaria prophylaxis does not afford full protection against infection. Contact advice centres for information about changing patterns of resistance and spread of malaria. (1,2)

Certain individuals are at higher risk of severe malaria and need to be forewarned - these include people who are immunocompromised and pregnant women.

Malarial chemoprophylaxis can be directed against various stages of the life cycle of the malaria parasite

• causal prophylaxis
  • directed against the liver stage (liver-stage schizonts of all 5 species)
  • NOT effective against P. vivax and P. ovale hypnozoite stage
  • ACMP recommends continuing the drug for 7 days after leaving a malarious area
    
    
• suppressive prophylaxis
  • directed against the red blood cell stages
  • should be taken for 4 weeks after leaving a malarious area
    
    
• prophylaxis against hypnozoites
  • primaquine is active against hypnozoites (present only in P. vivax and P. ovale)
    • also has causal prophylactic activity against the liver stage schizonts of all malaria parasites of humans
    • primaquine is occasionally used for terminal prophylaxis, also known as presumptive anti-relapse therapy (PART), to eradicate hypnozoites of P. vivax and P. ovale
      • however, the routine use of primaquine for prophylaxis or terminal prophylaxis is not recommended
      • primaquine is not licensed in the UK and practitioners considering the use of primaquine as a prophylactic agent should consult an expert centre
      • primaquine is an oxidant drug and can lead to significant haemolysis in G6PD-deficient individuals.

In addition to the use of an appropriate chemoprophylaxis, probably the best advice is to avoid being bitten. This involves the use of mosquito repellents - either applied to the skin or used in a particular room, the wearing of long sleeved shirts and trousers from dusk onwards, and sleeping under a mosquito net.

Travellers should purchase antimalarial chemoprophylaxis from a reputable source in the UK before departure.

The World Health Organization has recommended the malaria vaccine RTS,S for widespread use among children living in malaria endemic areas (3)

References

1. UK Health Security Agency. Malaria prevention guidelines for travellers from the UK (online). Last updated April 2025
2. Centers for Disease Control and Prevention. CDC Yellow Book 2024: health information for international travel. Section 5: travel-associated infections & diseases - malaria. May 2023 (internet publication).
3. Zavala F; RTS,S: the first malaria vaccine. J Clin Invest. 2022 Jan 4;132(1).