Pediatric Investigators Collaborative Network on Infections in Canada (PICNIC) Study of Malaria in Pediatric Patients in Canada: A Retrospective Review from 2014 to 2023

Objective: We studied malaria in Canadian children between 2014-2023, focusing on how often it occurs, who is affected, how severe it is, and how COVID-19 travel restrictions influenced cases. Design/Setting: We reviewed records from 11 children's hospitals across Canada. Participants: 431 children under 18 years old with laboratory-confirmed malaria. Results: The average age was 8 years; just over half were boys. Most children were born outside Canada (73%) and almost all had recently traveled to malaria-endemic regions (98%). Travel was often related to moving to Canada as migrants/refugees (56%) or visiting family abroad (38%). Few families sought pre-travel medical advice (36%), received malaria prevention prescriptions (33%), or followed them fully (23%). The most dangerous malaria parasite, Plasmodium falciparum, caused most infections (85%). Severe malaria occurred in nearly 40% of children, with 14% needing intensive care. One child died from unrelated causes. Use of the medicine artesunate was common, though some children later developed delayed anemia. Case numbers fell sharply during COVID-19 travel restrictions but rose again after 2022. The types of malaria parasites did not change, and delays in diagnosis remained frequent. Kidney injury was rarely detected using current Canadian guidelines (5%) but was common when international criteria were applied (53%). Only falciparum malaria clearly predicted severe illness. Conclusions: Malaria in Canada mostly affects newcomer families and those visiting relatives abroad, and often results in serious illness needing intensive care. Our findings show gaps in timely diagnosis, limited prevention before travel, and under-recognition of kidney complications with current Canadian guidelines. Updates to pediatric care guidance and stronger efforts to improve pre-travel counseling and malaria prevention are urgently needed.