Assessing the Effect of Neglected Tropical Diseases on Plasmodium Falciparum Transmission in an Area of Co-endemicity
Condition: Malaria Transmission
MeSH terms: Malaria
Study type: Observational

Summary: 
      Assessing the effect of neglected tropical diseases on Plasmodium falciparum transmission in
      an area of co endemicity.
    

Detailed description: 
      The project is divided in three different work packages that cover the life cycle of P.
      falciparum :

        1. In Work Package 1 (WP1) the investigators will assess whether S. haematobium infection
           increases the human reservoir of P. falciparum by increasing the carriage rate and
           incidence of P. falciparum gametocytaemia as well as by increasing the proportion and
           incidence of subject with sub-microscopic P. falciparum infection. The investigators
           will also determine whether this increase in gametocyte carriage is a consequence of an
           impairment of the immune response of helminth infected subjects to P. falciparum.

        2. In Work Package 2 (WP2) the investigators will determine whether the transmission of the
           sexual forms of P. falciparum from the human host to mosquito is increased in S.
           haematobium infected subjects compared to uninfected controls. Moreover the
           investigators will study whether the immunological changes induced in S. haematobium
           infected subjects lead to a decrease of the transmission reducing activity of IgG
           specific to Pfs48/45 and Pfs230 (both capable of blocking/impairing further development
           of P. falciparum in the mosquito gut).

        3. Finally in Work Package 3 (WP3) the investigators will assess whether S. haematobium
           infection affects the transmission of P. falciparum from the mosquito to the human host.
           This effect will be determined indirectly by assessing whether S. haematobium infected
           subjects are more attractive to mosquitoes.
    

Intervention name(s): Pre-treatment follow up; S. haematobium treatment; Post treatment follow up; Olfactometer experiment
Intervention type(s): Other; Other; Other; Other
Intervention description(s): No active intervention; medical support provided if needed; Praziquantel-treatment for S. haematobium positive volunteers; No active intervention; medical support provided if needed.; No active intervention; medical support provided if needed.
Other intervention name(s): Praziquantel-treatment
Intervention MeSH terms: Praziquantel
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        The study population are subjects aged from 6 to 30 years since both adults and children
        have been shown to be a reservoir of P. falciparum. Participants will be recruited in two
        African villages located in Gabon (lambarene) and Ghana Asokwa submetropolitan area in
        Kumasi, Ghana. Settings in the two locations are different and represent a rural area with
        very high infectious pressure from helminths infection (S. haematobium and geohelminths) as
        well as year-round transmission of malaria in the Central African rain forest (Lambaréné)
        and a more densely populated area in West Africa with pronounced seasonal variation in
        malaria transmission and high endemicity of S. haematobium but very little other
        helminthiases due to well-implemented mass treatment campaigns.
      
Biospecimen description: 
      Blood sample and urine collection potentially containing genetic material of Plasmodium
      falciparum and Schistosoma haematobium
    
Keywords: Schistosoma haematobium plasmodium falciparum transmission