Concurrent Helminthic Infection Protects Schoolchildren with Plasmodium vivax from Anemia

Abstract

Background Plasmodium vivax is responsible for a significant portion of malaria cases worldwide, especially in Asia and Latin America, where geo-helminthiasis have a high prevalence. Impact of the interaction between vivax malaria and intestinal helminthes has been poorly explored. The objective of this study was to evaluate the influence of intestinal helminthiasis on the concentration of hemoglobin in children with Plasmodium vivax malaria in rural areas in the municipality of Careiro, in the Western Brazilian Amazon.Methodology/Principal FindingsA cohort study was conducted from April to November 2008, enrolling children from 5 to 14 years old in two rural areas endemic for malaria. A cross-sectional evaluation was performed in April to actively detect cases of malaria and document baseline hemoglobin and nutritional status. Children were followed-up for six months through passive case detection of malaria based on light microscopy. Throughout the follow-up interval, hemoglobin value and stool examination (three samples on alternate days) were performed on children who developed P. vivax malaria. For 54 schoolchildren with a single infection by P. vivax, hemoglobin during the malaria episode was similar to the baseline hemoglobin for children co-infected with Ascaris lumbricoides (n = 18), hookworm (n = 11) and Trichuris trichiura (n = 9). In children without intestinal helminthes, a significant decrease in the hemoglobin during the malarial attack was seen as compared to the baseline concentration. In the survival analysis, no difference was seen in the time (in days) from the baseline cross-sectional to the first malarial infection, between parasitized and non-parasitized children.Conclusion/SignificanceFor the first time, a cohort study showed that intestinal helminthes protect against hemoglobin decrease during an acute malarial attack by P. vivax.

Epidemiology of Hookworm Infection in Kintampo North Municipality, Ghana: Patterns of Malaria Coinfection, Anemia, and Albendazole Treatment Failure

“…41 Similarly, in a study of Peruvian school children, there was a significant drop in hemoglobin during a symptomatic infection with Plasmodium vivax among children who were not infected with intestinal helminths, whereas anemia was not exacerbated in those harboring worms. 51 By contrast, others have reported varying increases in the risk of anemia with malaria and helminth coinfection across various age groups. 46,[52][53][54][55][56] Given that there are more than 400 million cases of P. falciparum each year, 57 many occurring in areas endemic for helminths, a greater understanding of the interaction between these two highly prevalent and clinically important parasitic diseases could lead to the formulation of more effective control strategies for both.…”

Epidemiology of malaria and helminth interaction

“…Using this generic definition, several studies reported a worsening effect of helminths on malaria incidence [35] and malaria-related diseases such as anemia [36][37][38] splenomegalia [31] and severe malaria [39], as well as negative birth outcomes [40]. Others studies contradicted the previous one by reporting an improvement of malaria-associated anemia during acute P. vivax malaria in Brazil [41], malaria infection [34] and malaria-associated anemia in school children [37] and severe malaria [42,43]. In contrast, many others studies reported very little contribution of helminth infection to malaria severity [12] and four did not find any association [44][45][46][47][48].…”

Malaria-Related Anemia in Patients from Unstable Transmission Areas in Colombia

“…23 Moreover, it is known that individuals with malaria infection are frequently coinfected with intestinal helminthes. [24][25][26] However, the role of those coinfections in the epidemiology and clinical outcome of malaria-related anemia continues to be unclear.…”