**Foreword**

#### *E (for elimination) = MC2 (for malaria control squared)*

'Before the role of anophelines in the spread of malaria was known, efforts to control the disease were sporadic, infrequent and insignificant' [1].

While malaria control is at crossroads [2], the book edited by Prof. Sylvie Manguin and Dr. Vas Dev is an important landmark in the current process of global malaria elimination. It is the first book that highlights so accurately the current situation and trends of malaria in Southeast Asia (SE Asia) and South America. It should be kept in mind that in some ways, the current malaria situation in SE Asia foreshadows what could be the situation in Africa South of the Sahara (SS), within the foreseeable future, given the major threat of spread of artemisinin resistance and consequent increase of cases. Then, a long-term scenario will possibly be the decrease of transmission (and immunity), outdoor transmission, localized vectors, malaria in adults, etc. Therefore, the research and proposals developed in SE Asia are of paramount importance to circumvent wrong track and implement efficient adapted Malaria Control Programs in Africa SS countries.

While comparing a former global geographic distribution of malaria in the 1960s (Figure 1) and the recently published CDC map (Figure 2), the following points clearly emerged:

Malaria disappeared from Europe (as thoroughly presented in a specific chapter of this book) and all countries of the northern hemisphere.

Malaria almost disappeared or is in control/elimination phase in several countries of SE Asia and South America despite great concerns (artemisinin-resistance, outdoor transmission, insecticide resistance, political instability, poverty, etc.), as clearly demonstrated in several chapters of this book, and malaria was recently eliminated from all north African countries after decades of various control interventions including environmental management.

Malaria is still present and vivid in almost all countries of Africa SS.

Figure 1 Global geographic structure of malaria in the late 1960s: (a) originally malaria-free, (b) malaria disappeared in 1950 without specific programme, (c) malaria eradicated by specific programme after 1950, (d) areas in consolidation phase of malaria eradication and (e) areas in attack phase or without eradication programme (Redrawn by L.P. Arsenyeva, M.A. Shakhova and E.P. Sokolova [3]).

Figure 2. CDC Malaria distribution map (CDC, 2018).

According to the last WHO Malaria Report [2], 18 countries reached malaria elimination since 2000 including Algeria (2016), Argentina (2013), Armenia (2011), Azerbaijan (2015), Egypt (2000), Georgia (2012), Iraq (2011), Kazakhstan (2004), Kyrgyzstan (2013), Morocco (2007), Oman (2004), Paraguay (2014), Sri Lanka (2015), Syrian Arab Republic (2007), Turkey (2012), Turkmenistan (2009), the United Arab Emirates (2000) and Uzbekistan (2013).

Not a single country of Africa SS is in this list, although concentrating some 90% of the burden of malaria in terms of morbidity and mortality and with a transmission of great intensity.

Therefore, the success and issues of malaria elimination in the 'green countries' of the map (Figure 2) must be used as lessons.

Malaria control in Africa SS is confronted with three main issues: biological, financial and structural, and social.

*Biological*: in Africa SS, the most efficient vectors such as *An. gambiae s.l*. and *An. funestus*, along with several other local vector species, are present, allowing permanent and high-intensity transmission with great ecological and socio-economic biodiversity. The pyrethroid resistance, added to previously well-described insecticide resistance, is of major concern, while scaling up of LLIN is in process, which induced the striking reduction of malaria observed this past decade. In addition, the most predominant *Plasmodium* species, *P. falciparum*, the deadliest one, is already resistant to commonly available drugs posing great concern that artemisinin-resistant strains, present in the Mekong Basin, arrive and spread all over Africa SS, like what happened with the amino-4-quinoleins drugs.

*Financial and structural*: due to the well-known issues of Peripheral Health Centers (PHCs), which often includes lack of data reliability [4, 5], their coverage and actual efficiency to diagnose and correctly treat malaria [6]. PHCs are doing passive case detection (PCD) only, and it is clear that there is a need to know what happens at the community level, and for that, active case detection (ACD) must be done. It is possible to combine PCD and ACD in developing mobile teams going and surveying populations on a regular basis, doing 'on-the-spot' some diagnoses using rapid detection tests (RDT) and giving first-line adequate treatment. According to a recent study of the Malaria Atlas Project dealing with population coverage of artemisinin-based combination therapy (ACT) based on survey data of 2003 and 2015, the coverage in ACT for children under 5 years old increased, but in 2015, only 19.5% of these children were likely to receive treatment. The likelihood of treatment was lower in poorer, rural populations. Indeed, the Africa Malaria Report [7] underlined that 'poor people are at increased risk of becoming infected with malaria and getting infected more frequently'. Child mortality rates are known to be higher in poorer households, and malaria is responsible for a substantial proportion of these deaths.

*Social*: a special accent must clearly be given to education, as well as wide campaign of information, communication and involvement of the communities, along with mass distribution of long-lasting impregnated nets (LLIN) with follow-up to avoid as much as possible their often-noticed misusage.

Nevertheless, since 2000, due to the implementation of considerable increased support and concerted integrated campaign, malaria in Africa SS halved. It was estimated that 663 million of clinical cases have been averted, and the result is largely attributable to the use of insecticide-treated nets (ITN) (68%), while ACT is responsible for 22% and insecticide residual spraying (IRS) for 10%. Thus, vector control contributed to some threefourths of malaria cases averted!

From the experience and issues of malaria control in SE Asia and South America, as they are well described in this book, it clearly appeared that malaria control in Africa SS must be based upon:

Research and development (R&D) of innovative tools including new drugs, novel insecticides, new vector control approaches [8], operational vaccines, improved housing, wide use of immunological markers to better evaluate the efficacy of the control measures [9] and intensified surveillance using spatial technologies. For example, it was recently demonstrated that modern houses with metal roof and finished walls are associated with >9% reduction in the odds of malaria in children of Africa SS when compared to traditional thatched houses [10]. Malaria elimination will need the implementation of integrated control management with better use of tools already available (LLIN, IRS and ACT) and new ones in development (as described in this book).

Special emphasis on education (remote learning system) and information-communication, thanks to recently developed media, smartphones, widely available even at the village level.

Strengthening health structures at peripheral, median and central levels to get accurate data on the current situation and their evolution with malaria control activities, along with improved diagnosis and malaria treatment but also of other infectious diseases so often not diagnosed and not rightly cured in due time.

Actual full involvement of all, from communities to the central level, national, international and non-governmental organizations (NGO).

Secure sustainable support at medium and long-term basis.

Actually, as it was recently well underlined, 'we must remain vigilant otherwise the striking improvement observed this last decade could be a bright interval, if financial, logistic and training support are not maintained as they have to be' [11]. Also, in the last Malaria Report [2], the WHO rings the alarm bell recognizing that 'after an unprecedented period of success in global malaria control, progress has stalled' in 2016 with even an increase (of 5 millions) of malaria cases over 2015 and deaths reaching 445,000 cases, a similar number with the previous year.

Nevertheless, this book *Towards Malaria Elimination*: *A Leap Forward* is an excellent encouragement for malaria programme managers, revealing the malaria situations and the effectiveness of the methods implemented in SE Asia and South America, thus paving the way to what needs to be implemented in Africa SS for a progressive but real elimination of malaria on this continent, as it has been possible to obtain elsewhere.

> *Pierre Carnevale, PhD, DRCE, Full Research Professor* Formerly with the Institute of Research for Development (IRD) Portiragnes, France Correspondence to: pjcarnevale2001@yahoo.fr

#### **References**


Preface

2030' [5].

Malaria, even though preventable and curable, continues to inflict insurmountable morbidi‐ ty particularly in resource-poor countries affecting equitable socio-economic development. Over the past few decades, a lot of new information has been generated on disease distribu‐ tion and determinants in understanding parasite biology and vector bionomics aided by molecular tools [1,2], but what ails mankind is the proper utilization of study results and equity in healthcare services in place and time, as well as lack of unified intercountry strat‐ egies to contain the disease spread. *Plasmodium* parasites and their vectors are continuously evolving in the changing disease epidemiology landscape challenging the human endeav‐ ours to conquer malaria. Human population with the expanding growth of "after popula‐ tion" movements are also increasingly functioning as 'vectors' of the disease. Human malaria parasites are getting multi-resistant to available armamentarium and so do mosqui‐ to vector species to insecticides establishing outdoor transmission hard to control, evading exposure. However, at the turn of century, the advent of new intervention tools including Noble prize–winning discovery of artemisinin by Tu Youyou for treatment of malaria, com‐ bined with large-scale implementation of insecticide-treated netting materials for vector containment, has once again renewed the optimism of malaria elimination globally. With large-scale funding from international agencies/philanthropists for 'universal coverage' of these intervention tools, malaria map is shrinking with more than 35 countries certified to be malaria-free and another 21 countries that are likely to reach zero indigenous transmission (categorized by WHO as E-2020) set to be declared malaria-free by 2020 [3,4]. Many more countries are moving forward from control to elimination, and given the continuing declin‐ ing trends of malaria transmission, WHO has given a clarion call for 'Malaria-Free World by

Nevertheless, the path to malaria elimination seems to be an uphill task given the con‐ straints and myriad of challenges. After a decade of decrease of malaria cases and deaths in all regions of the world due to roll-out of core interventions, including wide-scale use of long-lasting insecticidal nets and improved treatments, WHO expressed the concern that malaria control is stalling and could reverse the gains due to insufficient funding and defi‐ ciency of political will [3]. However, a number of bodies and alliances have come forward, viz., Malaria Eradication Scientific Alliance (MESA), Malaria Eradication Research Agenda (malERA), Multilateral Initiative on Malaria (MIM), Asia Pacific Leaders Malaria Alliance (APLMA), Asia-Pacific Malaria Elimination Network (APMEN) and Regional Malaria Elimi‐ nation Initiative (RMEI), involved at different scales, for shared experiences and to promote coordinated actions for decisive attack to 'kill malaria'. In addition, after decades of the use of routine vector control tools based on insecticides, scientists are now deploying new inno‐ vative approaches that are environment-friendly to be used in integrated control manage‐ ment that would include chemotherapy, vector control, manipulation of environmental and ecological characteristics, and vaccination. This book is one little step forward to bring to‐ gether experiences of 67 malaria experts from 5 continents to present updated information
