Prevalence of gastrointestinal symptoms in patients with influenza, clinical significance, and pathophysiology of human influenza viruses in faecal samples: what do we know?

Abstract

This review provides for the first time an assessment of the current understanding about the occurrence and the clinical significance of gastrointestinal (GI) symptoms in influenza patients, and their correlation with the presence of human influenza viruses in stools of patients with confirmed influenza virus infection. Studies exploring how human influenza viruses spread to the patient’s GI tract after a primary respiratory infection have been summarized. We conducted a systematic search of published peer-reviewed literature up to June 2015 with regard to the above-mentioned aspects, focusing on human influenza viruses (A(H1N1), A(H1N1)pdm09, A(H3N2), and B). Forty-four studies were included in this systematic review and meta-analysis. The pooled prevalence of any digestive symptoms ranged from 30.9 % (95 % CI, 9.8 to 57.5; I2 = 97.5 %) for A(H1N1)pdm09 to 2.8 % (95 % CI, 0.6 to 6.5; I2 = 75.4 %) for A(H1N1). The pooled prevalence of influenza viruses in stool was 20.6 % (95 % CI, 8.9 to 35.5; I2 = 96.8 %), but their correlation with GI symptoms has rarely been explored. The presence of viral RNA in stools because of haematogenous dissemination to organs via infected lymphocytes is likely, but the potential to cause direct intestinal infection and faecal–oral transmission warrants further investigation. This review highlights the gaps in our knowledge, and the high degree of uncertainty about the prevalence and significance of GI symptoms in patients with influenza and their correlation with viral RNA positivity in stool because of the high level of heterogeneity among studies.Electronic supplementary materialThe online version of this article (doi:10.1186/s12985-015-0448-4) contains supplementary material, which is available to authorized users.

Clinical differences of influenza subspecies among hospitalized children

“…Gastrointestinal symptoms including vomiting, diarrhea, and abdominal pain may be observed with varying frequencies during the course of influenza infection. According to a meta-analysis compiled by Minodier et al (16), this rate ranged between 2.8% and 30.9% for influenza A infection.…”

Clinical and virological factors associated with gastrointestinal symptoms in patients with acute respiratory infection: a two-year prospective study in general practice medicine

“…First, each winter, ARIs and gastroenteritis outbreaks overlap, creating a spurious association between ARI and GI symptoms, maybe caused by a co-infection between respiratory agents and enteroviruses [16]. Second, GI symptoms may be a side effect of drug treatment (antibiotic or antiviral) [17,18] or food consumption (ex: raw shellfish and molluscs) [19]. Third, GI symptoms could either be a manifestation of a direct viral effect, or an indirect viral effect of respiratory viruses, such as lung-derived CD4+ cell-induced dysbiosis resulting in intestinal injury [20].…”

Influenza‐like illness in healthcare personnel at a paediatric referral hospital: Clinical picture and impact of the disease

“…In our population, approximately one‐fifth of those assessed reported diarrhoea as a symptom. The prevalence of gastrointestinal symptoms has been reported in the literature to range from 2.8% to 30.9%, depending on the influenza subtype …”