Etramp5 as a useful serological marker in children to assess the immediate effects of mass drug campaigns for malaria.

INTRODUCTION: Serological methods provide useful metrics to estimate age-specific period prevalence in settings of low malaria transmission; however, evidence on the use of seropositivity as an endpoint remains scarce in studies to evaluate combinations of malaria control measures, especially in children. This study aims to evaluate the immediate effects of a targeted mass drug administration campaign (tMDA) in Haiti by using serological markers. METHODS: The tMDA was implemented in September-October 2018 using sulfadoxine-pyrimethamine and single low-dose primaquine. A natural quasi-experimental study was designed, using a pretest and posttest in a cohort of 754 randomly selected school children, among which 23% reported having received tMDA. Five antigens were selected as outcomes (MSP1-19, AMA-1, Etramp5 antigen 1, HSP40, and GLURP-R0). Posttest was conducted 2-6 weeks after the intervention. RESULTS: At baseline, there was no statistical difference in seroprevalence between the groups of children that were or were not exposed during the posttest. A lower seroprevalence was observed for markers informative of recent exposure (Etramp5 antigen 1, HSP40, and GLURP-R0). Exposure to tMDA was significantly associated with a 50% reduction in the odds of seropositivity for Etramp5 antigen 1 and a 21% reduction in the odds of seropositivity for MSP119. CONCLUSION: Serological markers can be used to evaluate the effects of interventions against malaria on the risk of infection in settings of low transmission. Antibody responses against Etramp5 antigen 1 in Haitian children were reduced in the 2-6 weeks following a tMDA campaign, confirming its usefulness as a short-term marker in child populations.

[Update of knowledge on Neglected Diseases in Haiti: Mansonelliasis, Tungiasis, Leprosy, and Anthrax]. / Mise à jour des connaissances concernant quatre maladies délaissées en Haïti : mansonellose, tungose, lèpre, charbon.

Haiti, like most limited-resources countries in the world, faces numerous neglected infectious diseases. They represent a real public health issue with lethal consequences especially in children. We are reviewing here the available literature on four neglected infectious diseases, mansonelliasis, tungiasis, leprosy and anthrax. Filariasis, due to Mansonella ozzardi, has been totally neglected since its discovery in 1920 in Haiti; it persists in coastal homes with a high prevalence in adults when an effective treatment is available. The skin lesions caused by Tunga penetrans have existed since the pre-Columbian period in Haiti. They persist in the most retreated and hard-to-reach areas where the population lives in precarious conditions and in extreme poverty. New available research data show the importance of the problem with very high prevalence rates in some rural communities far away from any healthcare center. Cases of leprosy are recently reemerging as no monitoring program has been in place since 2004. Finally, anthrax is still endemic; small epidemics resurfacing periodically in families in rural areas. Screening of people for these diseases and managing the cases are necessary to improve health and reduce morbidity and mortality in Haiti.

Comme dans la plupart des pays pauvres de la planète, les maladies infectieuses négligées sont nombreuses en Haïti où elles représentent un réel problème de santé publique avec des conséquences létales, surtout pour les enfants. Nous faisons le point des données accessibles pour quatre d'entre elles. Totalement délaissée depuis la découverte de sa présence en Haïti en 1920, la filariose due à Mansonella ozzardi persiste en foyers côtiers avec une prévalence élevée chez les adultes alors qu'un traitement efficace est disponible. Connues depuis la période précolombienne dans l'île d'Hispaniola, les lésions cutanées dues à Tunga penetrans persistent dans les régions les plus reculées et difficiles d'accès où la population vit dans des conditions précaires et dans une très grande pauvreté. Nous rapportons les données d'enquêtes récentes qui montrent l'importance de cette ectoparasitose en Haïti où les taux de prévalence sont très élevés dans certaines communautés rurales isolées. Des cas de lèpre resurgissent en Haïti alors qu'aucun programme de surveillance n'est effectif depuis 2004. Enfin, la maladie du charbon est endémique dans les régions d'élevage où des épidémies familiales resurgissent périodiquement en milieu rural. Le dépistage des personnes atteintes de ces maladies et leur prise en charge sont nécessaires pour une amélioration de la santé et une baisse de la mortalité en Haïti.

[Gametocyte carriage in asymptomatic Plasmodium falciparum infections in Haiti (2010-2013)]. / Portage de gamétocytes de Plasmodium falciparum en Haïti en 2010-2013.

A survey conducted from May 2010 to October 2013 in five from ten departments of Haiti among 5,342 persons aged from 1 to 107 years showed a gametocytic rate = 3.2%. However, it varies greatly from one Department to another, ranging from 0.5% in Grande Anse Department to 5.9% in Southeast Department. Malaria is present in Haiti in heterogeneous coastal foci. Gametocytes occur at all ages, but two times most often in male under 20 years. Entomological studies in Haiti are needed to better characterize the relationships between man and the vector Anopheles albimanus, adapting the fight more effectively.

[Epidemiological characteristics of malaria in the village of Corail, Grand'Anse, Haiti]. / Caractéristiques épidémiologiques du paludisme dans la commune de Corail, Grande Anse, Haïti.

Malaria is considered to be a major problem of public health in Haiti. However the impact of Plasmodium falciparum on health is poorly known in this country. The objective of this study is to verify the incidence of malaria as the cause of hospital consultation and to evaluate the rate of P. falciparum gametocytes carriage among the population living in a municipality within the Department of Grand'Anse where the prevalence of malaria is considered one of the strongest in Haiti. Analysis of hospital statistics of Corail (Grand'Anse) showed that only 17.4% of consultations of patients presenting with fever are due to microscopically confirmed malaria. The fraction of the population most affected is that of adults aged 15-39 years (55% of cases). Children under five represent only 11% of the cases. A community survey showed the rarity of the carriage of gametocytes in asymptomatic persons (0.9%). In Haiti, the epidemiological characteristics of malaria must have specified and documented field studies in order to adapt a strategy for fighting against this parasitic disease with greater efficiency.