[6] Because many of the people had been forced to leave their homes and were living in internally displaced person camps or orphanages, Karerwa visited them to extend her peace education project.
[7] In 2003, Karerwa was appointed to serve on the Provincial Education Council by the governor of Gitega Province, as the representative for primary school teachers.
[12] In 2014, she led Burundian delegation at the African Caribbean Pacific-European Union Joint Parliamentary Assembly held in Port Louis, Mauritius.
Among the issues discussed were regional economic integration, enhanced cooperation on transportation and digital connections, coordination of systems to stem terrorism and conflict, improvements in services and protection for women and children, and strengthening democracy and accountability with a focus on human rights.
[13] She served on the ACP-EU Assembly's Commission of Economic Development, Financial and, Commercial Affairs co-chaired by Nela Khan (Trinidad and Tobago) and Derek Vaughan (Wales).
Among her appointments were to the commission which monitored regulations of the assembly,[15] and vice president of the Committee on Social Affairs, Repatriation, Equal Opportunities and the Fight against AIDS.
[17] Karerwa served on the EALA commission for the 4th assembly, along with other women including Oda Gasinzigwa (Rwanda), Josephine Lemoyan (Tanzania), and Wanjiku Muhia (Kenya).
[19] That term, she was part of a team of members of the EALA Parliament who visited Burundi and Rwanda in 2018 in an attempt to begin repairing the Burundi–Rwanda relations, which had been deteriorating for several years.