Study uncovers ‘enormous burden of dengue’ among Kenyan children
Researchers uncovered what they called “an enormous burden of dengue fever among children with undifferentiated febrile illness in Kenya.”
Specifically, out of more than 1,000 children ill with fever, more than 40% were infected with dengue virus. Many children with dengue and without malaria were treated with antimalarial drugs, antimicrobial drugs or both, according to a report in Emerging Infectious Diseases.
Dengue, which is endemic in more than 100 countries, “is an important cause of illness among children in Kenya, and clinicians should consider dengue as a cause of unlocalized fever,” Melisa M. Shah, MD, MPH, an endowed postdoctoral fellow at Stanford Medicine, told Healio.
“Often, fever is considered to be malaria and empiric treatment is given,” Shah said. “The lack of awareness about dengue as a cause of febrile illness is one factor causing the overdiagnosis and overtreatment of malaria.”
Shah and colleagues tested blood samples from 1,022 Kenyan children with ongoing febrile illness from 2014 to 2017. Of the 862 viable samples, dengue viremia was detected in 361 (41.9%). Of those 361 samples, 333 were classified as primary infections (92.2%), 14 were secondary infections (3.9%) and the remaining 14 samples lacked dengue virus immunoglobulin G data.
Of the 1,022 study participants, 419 (41%) received antimalarial drugs, Shah and colleagues reported. Antimalarial drugs were more likely to be administered to patients with dengue virus viremia — 48.8% vs. 36.8%. Among 141 study participants who had confirmed dengue without malaria, 29 (20.6%) received an antimalarial drug (20.6%), 75 received an antimicrobial drug (53.2%) and 12 received both (8.5%).
“The unnecessary use of antimalarials and antibiotics exposes children to known medication side effects and may contribute to the development of drug resistance,” Shah said.
Participants with dengue virus viremia with febrile illness reported headaches (49.6%), poor appetite (46.8%), cough (45.7%) and joint pain (36.8%).
“An accurate, reliable and affordable point-of-care diagnostic for dengue is urgently needed for health practitioners in outpatient settings in endemic areas,” Shah said. “Such a diagnostic could quickly identify whether dengue may be the cause of febrile illness.”
According to a CDC summary of the study, genetic testing revealed that some of the strains of dengue virus were not typical to Africa and may have been imported by travelers from other continents.
“The paucity of dengue surveillance studies and sequence data from Africa is striking,” Shah and colleagues wrote in their paper.
WHO estimates that around half of the world’s population is currently at risk for dengue, which is typically found in urban and semi-urban areas in tropical and sub-tropical climates. Researchers predicted last year that the geographical range of dengue would place 60% of the world’s population at risk by 2080.
Right now, an estimated 100 million to 400 million dengue infections occur each year, according to WHO. There is no specific treatment, although there is an approved dengue vaccine.
“Dengue activity will likely continue to spread in Africa because of rapid land use change, climate change, urbanization, increased human travel and international trade,” Shah and colleagues wrote. “Knowledge of the spatial–temporal dynamics of dengue circulation throughout Africa is critically needed to inform a coordinated public health response in an increasingly interconnected world.”