Prospective case-control study of dengue infection in some malaria and non-malaria patients consulting at the Bertoua Regional Hospital, East-Cameroon

In Cameroon, recent studies have documented several cases of dengue infection in some urban areas, but dengue-malaria coinfection malaria was little investigated, especially in the East region. From the 6th July to the 4th September 2020, a case-control study including 50 cases (malaria-positive subjects) and 90 controls (non-malaria subjects) was carried out at the Bertoua Regional Hospital. Participants were prospectively enrolled and administered with a questionnaire to record information such as age, sex, dwelling place, dengue knowledge, and the environments quality. Blood specimens were then collected and screened for dengue infection using the NS1/IgG/IgM rapid diagnostic tests and hematological parameters were measured using a MINDRAY-type hemacytometer. Of the malaria patients, 14% (7/50) were tested positive for dengue fever against 66.66% for the controls (60/90). Most malaria patients had a secondary dengue infection (57.14%, 4/7) while most of the non-malaria patients faced a primary infection (61.66%, 37/60). In both groups, women were more exposed than men to dengue and there was a significant association between the dwelling place and dengue seropositivity. Moreover, young subjects <16 years old were significantly more associated with dengue than 16-30 years old (OR=16.24, P=0.042 for cases vs, OR=21, P=0.0001 for controls). The analysis of hematological parameters showed a significant decrease (P<0.001) in platelets in cases compared to control. These results suggest that dengue fewer targets malaria- than non- malaria patients with different serological characteristics in Bertoua city. However, co-infected patients demonstrated a greater clinical vulnerability than monoinfected patients, urging the need for epidemiological surveillance.