Influenza, Malaria parasitaemia and Typhoid fever Coinfection in Children: Seroepidemiologic Investigation in Four Healthcare Centres in Lagos, Nigeria

Abstract Background : According to WHO, out of about one billion individuals usually infected with influenza virus, children from developing countries account for 99% of deaths due to related infections. There is dearth of clinical-epidemiological information on the trio of influenza, malaria, and typhoid fever co-infection in Nigeria. Similarity of their clinical symptoms coupled with lack of vaccine and all year-round circulation in sub-Saharan Africa cause serious paediatric morbidity and mortality. This study therefore investigated influenza, malaria and typhoid fever coinfection among children in Lagos, Nigeria. Methods : A sero-epidemiologic hospital-based study was designed. Blood from 364 children tested by RDT for malaria HRP-II/pLDH (Accessbio or Medicon BioCheck, USA) and typhoid (CTKBiotech, USA or Omega, UK) were screened by ELISA (Demeditec, Germany) for influenza virus specific IgM antibody. Descriptive statistics was used and p-values were determined with Chi-square. Results : Demographic data showed median age of 3 (mean 3.8, mode 2, range 0-14) years. Out of the 364 samples tested, 76/364 (20.9%) were seropositive for influenza A virus. Of the 76 seropositive patients, 47/76 (61.8%) had malaria parasitaemia, 42/76 (55.3%) had typhoid, and 21/76 (27.6%) were co-infected with malaria parasitaemia and typhoid fever. Furthermore, 2/76 (2.6%) children having underlying health condition of sickle cell anaemia recorded influenza seropositivity. Ojo primary healthcare centre had the highest seroprevalence of 48.7% (37/76), age group 1-4 years recorded the highest seroprevalence of 55.3% (42/76), the highest serologic evidence of 61.8% (47/76) was detected among male children, while fever 27.6% (21/76) was the most common of all the clinical symptoms recorded. Although, the month of March had the highest seroprevalence of 20/76 (26.3%), seropositivity was recorded in all other months considered for this study. Conclusions : We hereby report the first paediatric co-infection of influenza, malaria and typhoid fever with a percentage seroprevalence of 27.6% among all age group round the months. Low co-infection was however recorded in children having sickle cell anaemia. Annual vaccination is strongly recommended for children of all ages in order to prevent co-infection of influenza with other deadly diseases.