Influenza Division, Centers for Disease Control and Prevention, Atlanta, GA, United States; Influenza Program, Centers for Disease Control and Prevention-South Africa, Pretoria, South Africa; United States Public Health Service, Rockville, MD, United States; Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Sandringham, South Africa; School of Public Health, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa; Division of Applied Research and Technology (DART), National Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control and Prevention, Cincinnati, OH, United States; University of Illinois, Springfield, IL, United States
Cohen, A.L., Influenza Division, Centers for Disease Control and Prevention, Atlanta, GA, United States, Influenza Program, Centers for Disease Control and Prevention-South Africa, Pretoria, South Africa, United States Public Health Service, Rockville, MD, United States; McMorrow, M., Influenza Division, Centers for Disease Control and Prevention, Atlanta, GA, United States, United States Public Health Service, Rockville, MD, United States; Walaza, S., Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Sandringham, South Africa, School of Public Health, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa; Cohen, C., Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Sandringham, South Africa, School of Public Health, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa; Tempia, S., Influenza Division, Centers for Disease Control and Prevention, Atlanta, GA, United States, Influenza Program, Centers for Disease Control and Prevention-South Africa, Pretoria, South Africa, Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Sandringham, South Africa; Alexander-Scott, M., Division of Applied Research and Technology (DART), National Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control and Prevention, Cincinnati, OH, United States, University of Illinois, Springfield, IL, United States; Widdowson, M.-A., Influenza Division, Centers for Disease Control and Prevention, Atlanta, GA, United States
Infectious diseases and underlying medical conditions common to Africa may affect influenza frequency and severity. We conducted a systematic review of published studies on influenza and the following co-infections or co-morbidities that are prevalent in Africa: dengue, malaria, measles, meningococcus, Pneumocystis jirovecii pneumonia (PCP), hemoglobinopathies, and malnutrition. Articles were identified except for influenza and PCP. Very few studies were from Africa. Sickle cell disease, dengue, and measles co-infection were found to increase the severity of influenza disease, though this is based on few studies of dengue and measles and the measles study was of low quality. The frequency of influenza was increased among patients with sickle cell disease. Influenza infection increased the frequency of meningococcal disease. Studies on malaria and malnutrition found mixed results. Age-adjusted morbidity and mortality from influenza may be more common in Africa because infections and diseases common in the region lead to more severe outcomes and increase the influenza burden. However, gaps exist in our knowledge about these interactions.