Dembinski Jennifer L, Mihret Adane, Yimer Solomon A, Tessema Bamlak, Trieu Mai-Chi, Tarekegn Azeb, Getachew Nahom, Cox Rebecca J, Oftung Fredrik, Haneberg Bjørn, Aseffa Abraham, Mjaaland Siri
Departments of Immunology and.
Vaccine Preventable Diseases, Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.
Open Forum Infect Dis. 2017 Feb 11;4(1):ofx026. doi: 10.1093/ofid/ofx026. eCollection 2017 Winter.
Influenza in children who reside in tropical and subtropical regions has until recently been regarded as insignificant. However, new evidence suggests that it significantly impacts hospitalization and promotes secondary bacterial coinfections. Ethiopia is situated in a subtropical area where influenza viruses are likely to circulate year round.
Clinical data were recorded in a cohort of 103 healthy preschool children recruited in Addis Ababa, Ethiopia. Humoral and cellular immune responses to influenza virus were determined by hemagglutination inhibition (HI) and interferon-γ enzyme-linked immunospot assays.
Ninety-six percent of the children (2-5 years old) had pre-existing HI antibody responses to 1 or more of the circulating influenza A subtypes, H1N1 (51%), H3N2 (86%), or influenza B (51%) strains. At the age of 4, all children had been infected with at least 1 strain, and 75% had been infected with 2-4 different viral strains. CD4 and CD8 T-cell responses against conserved viral antigens increased with repeated exposures, indicating boosting of cross-reactive cellular immunity. Malnutrition did not seem to affect these immune responses to influenza.
Influenza is highly prevalent among children in this area of Ethiopia. Due to the risk of secondary bacterial pneumonia, increased influenza awareness might benefit child health.
直到最近，居住在热带和亚热带地区的儿童流感一直被认为影响不大。然而，新证据表明，它对住院治疗有重大影响，并会引发继发性细菌合并感染。埃塞俄比亚位于亚热带地区，流感病毒可能全年传播。
记录了在埃塞俄比亚亚的斯亚贝巴招募的103名健康学龄前儿童队列的临床数据。通过血凝抑制（HI）和干扰素-γ酶联免疫斑点试验确定对流感病毒的体液和细胞免疫反应。
96%的儿童（2至5岁）对1种或更多种流行的甲型流感亚型、H1N1（51%）、H3N2（86%）或乙型流感（51%）毒株已有HI抗体反应。4岁时，所有儿童至少感染过1种毒株，75%的儿童感染过2至4种不同的病毒毒株。针对保守病毒抗原的CD4和CD8 T细胞反应随着反复接触而增加，表明交叉反应性细胞免疫增强。营养不良似乎并未影响对流感的这些免疫反应。
流感在埃塞俄比亚这一地区的儿童中高度流行。鉴于继发性细菌性肺炎的风险，提高对流感的认识可能有益于儿童健康。
