Medical Implications of Coinfection With Malaria and Filariasis Parasites
Condition: Malaria; Filariasis
MeSH terms: Malaria; Coinfection; Filariasis; Elephantiasis
Study type: Observational

Summary: 
      This study will examine the clinical, immunological and epidemiological effects of concurrent
      infections with P. falciparum and W. bancrofti or M. perstans (the parasites that cause
      malaria and filariasis) on the frequency and severity of malaria infection in children and
      young adults in Mali, Africa.

      Residents of Tien gu bougou and Bougoudiana, Mali, who are between 1 and 20 years of age may
      be eligible for this study. Participants with and without filarial infection will be
      enrolled.

      Participants undergo the following tests and procedures:

        -  Baseline evaluation with medical history and physical examination, blood tests and stool
           culture

        -  Brief physical examinations weekly

        -  Blood tests monthly for malaria

        -  Standard treatment offered for anyone with malaria

        -  Blood tests for filarial infection at the beginning, midpoint and end of the
           transmission season

        -  Treatment for lymphatic filariasis is available through the National Program for the
           Elimination of Lymphatic Filariasis. There is no effective standard therapy for M.
           perstans.

        -  Treatment for other parasitic worm infections, if needed.
    

Detailed description: 
      Residents of malaria-endemic regions are frequently exposed to a variety of other parasites
      concurrently with malarial parasites. In Mali, lymphatic filariasis due to Wuchereria
      bancrofti co-exists in several regions highly endemic for malaria, and co-infection is common
      in the residents of these areas. Because of the chronicity of filarial infections and an
      associated bias towards the development of an adaptive immune response dominated by Th2
      cytokines, a pre-existing filarial infection has the potential to alter the immune response
      towards incoming malarial parasites, clearance of which are considered to be dependent on a
      robust Th1 response. This could, in turn, affect the clinical manifestations and outcomes of
      malaria infection. Conversely, immune responses to filarial parasites may be modulated in the
      presence of malarial parasites. In addition to sharing a human host, Plasmodium falciparum
      and Wuchereria bancrofti are transmitted by the same mosquito vector, Anopheles gambiae, and
      interaction between the two species in the vector may have important implications for
      transmission of these two infections. The primary goals of this study are to determine the
      effect of concurrent infections with P. falciparum and W. bancrofti parasites on the
      prevalence and severity of malaria infection in children living in a Malian village
      co-endemic for two parasites and to assess the effects of co-infection on the immune
      responses to these two parasites over the course of the malaria transmission season. The
      epidemiology of co-infection at the human and vector level will also be examined.
    

Time perspective: Prospective
Keywords: Malaria; Filariasis; Coinfection; Co-Infection