Malaria, an acute febrile illness caused by Plasmodium parasites, is transmitted through the bites of infected female Anopheles mosquitoes. According to the World Malaria Report 2020, the disease remains a global threat, with an estimated 229 million malaria cases in 2019. Recently, the decline in the incidence rate has slowed, with only a two percent reduction between 2015 and 2019.

 

The WHO African region accounts for more than 90% of all malaria cases and deaths, and most of them result from the transmission of Plasmodium falciparum, one of the deadliest malaria parasites. The new vaccine RTS,S acts against P. falciparum and is mainly administered to children five months and older in four separate doses. This sequence of shots is required to effectively immunize children against repeated infections.

 

 

According to the WHO, private and public health organizations have researched for years in search of solutions, including pharmaceutical companies such as GSK and non-profit organizations such as the Program for Appropriate Technology in Health (PATH). After almost 30 years of development, RTS,S was finally ready for testing in reallife settings, leading to the implementation of a pilot program in three African countries — Ghana, Kenya, and Malawi — starting in 2019. The WHO aimed to collect evidence on the effects of RTS,S, with a specific focus on reducing child deaths.

 

With future malaria interventions relying on pilot results, RTS,S tests were carried out in careful and precise steps. After rigorous clinical trials in areas with high malaria transmission, the RTS,S Clinical Trials Partnership announced that the vaccine prevented a substantial number of clinical malaria cases in infants and young children. With the intention to scale up this implementation, an evaluation team was also established for surveillance and asked to find the most appropriate vaccination method and period.

 

Despite the tremendous global effort, RTS,S development has been a lengthy process due to the nature of the disease itself. Professor Kim Rockli (Department of Health Policy and Management) explains, “The Plasmodium parasite that causes malaria is constantly mutating, and the complexity of the immune response to malaria made it very difficult to develop a vaccine against it.” Given this difficulty, the endorsement of RTS,S, which Professor Kim describes as “the first vaccine to be developed for infection caused by a parasite,” is a truly phenomenal success.

 

 

Before the official registration of RTS,S, methods for preventing malaria were primarily chemical, such as the use of insecticide-treated nets and DDT. Despite the overall success of these approaches, there were some limitations, such as misusing the bed nets as fishing nets in areas with high poverty rates. Moreover, DDT has fallen out of favor due to its negative effects on human health and the environment.

 

Hopefully, the expansion of the use of the malaria vaccine will overcome the current weaknesses in malaria control. Collected data from pilots show that there has been no decrease in the use of insecticide-treated nets in areas where the vaccine has been introduced. In fact, the WHO has announced that the combination of RTS,S and bed nets has resulted in “over 90% of children benefitting from at least one preventive intervention.” Based on the results of malaria vaccine pilots, RTS,S is expected to lead to equity in access to malaria prevention and act synergistically with existing interventions.

 

 

To maintain this success, however, continuous efforts to aid vaccine production, monitor its distribution, and examine its effectiveness are needed. Professor Kim explains, “Funding decisions within the global health community, securing a sustainable supply chain and distribution channels, and examining the feasibility of administering four doses in health systems that are already constrained are all important issues to be discussed among the stakeholders.” In addition to investments in the treatment itself, improving health infrastructure and creating an atmosphere of social and political support are essential for ensuring vaccination effects.

 

Tackling a global health problem requires a set of solutions that are put into action by the efforts of several actors. Malaria can neither be solved by a single solution nor a single actor. Likewise, vaccines are an effective remedy that can be added to the existing malaria eradication tool kit but are clearly not the panacea that everyone was expecting. Given this, continued investments in other preventives, diagnostics, and treatments are also important, as Professor Kim explains. “Like any other global health problem, there is no single magic bullet for eliminating malaria. The vaccine should be considered one of the solutions – not the sole solution – for preventing malaria cases.”

 

In fact, climate change has emerged as one of the major obstacles to eradicating malaria. According to global organizations such as the WHO, an increase in temperature and rainfall may lead to a potential increase in malaria transmission. With the expansion of mosquito habitats, countries with low malaria risk, including Korea, now face new threats of possible infections. An abundant supply of vaccines, other treatments, and preventions are needed to respond flexibly to the fluctuating demand. As Professor Kim underlines, international efforts and collaboration are also needed to mitigate climate change and its indirect impacts on the burden of disease globally.

 

As the output of international efforts and cooperation, the approval of RTS,S has raised hopes that the world can be saved from malaria. It is definitely a historic moment — a step closer to reaching the goal of malaria eradication. However, the world should accept this success as a new beginning, not an end, with a view to sustaining the vaccination process and responding to the remaining challenges.