Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (KN1097/3-1, KN1097/3-2, RO3055/2-1, RO3055/2-2)
Received: 21 November 2019
Accepted: 18 May 2020
First Online: 3 June 2020
Ethics approval and consent to participate
: Ethical approval was granted by the National Research Ethics Committee at the National Institute for Medical Research (NIMR) in Tanzania (Ref No. NIMR/HQ/R.8a/Vol. IX/1562) and the University of Goettingen in Germany (8/812An). Further permission to conduct the study was obtained from the regional and district authorities in the respective study sites. Parents or legal guardians provided a written informed consent for their children to participate into the study. Assent to participate was also sought from the respective child. Sample collection and documentation was done according to the Helsinki Declaration as last revised by the 64th World Medical Association general assembly in 2013 [CitationRef removed]. The study has been reported according to the STROBE checklist for cross-sectional studies.
: Written informed consent for publication was obtained from parents or legal guardians of the participants.
: Authors declare that they have no competing interests.