Studies on post-infectious functional gastrointestinal disorders (FGID) after viral infections
| Study | Patients/controls (n) | Pathogen | Frequency of FGIDs among cases | Frequency of FGIDs among controls | Follow-up (months) |
| Marshall et al (2007)41 | 89/29 | Norovirus | IBS: 23.6% | IBS: 3.4% | 3 |
| Zanini et al (2012)42 | 186/198 | Norovirus | IBS: 21.5% | IBS: 1.5% | 12 |
| Saps et al (2009)43 | 44/44 | Rotavirus | FGIDs: 16%) | FGIDs: 3/44 (7%) | 24–48 |
| Ghoshal et al (2021)45 | 280/264 | SARS- CoV-2 | IBS: 5.3% UD: 2.1% IBS-UD overlap: 1.8% | IBS: 0.3% | 6 |
| Velez et al (2021)46 | 200 /no controls | SARS-CoV-2 | IBS: 29% FD: 1% Overlap: 9.5% | – | 6 |
| JW Blackett et al (2022)47 | 749 /no controls | SARS-CoV-2 | 9.6%—diarrhoea 11%—constipation 9.4%—abdomen pain 7.1%—nausea/vomiting 16%—heartburn | – | 6 |
| Oshima et al (2021)50 | 5157 /no controls | SARS-CoV-2 | FD: 8.5% IBS: 16.6% FD-IBS overlap: 4.0% | – | 6 |
| Nakov et al (2022)51 | 1896/980 | SARS-CoV-2 | IBS (26.3% vs 20.0%) Functional dyspepsia (18.3% vs 12.7%), Heartburn (31.7% vs 26.2%) Self-reported milk intolerance (43.5% vs 37.8%) | – | 6 |
| Noviello et al (2021)52 | 164/183 | SARS-CoV-2 | Adjusted RRs for loose stools and somatisation were increased after infection: 1.88 (0.99–3.54) and 3.62 (1.01–6.23) | – | 5 |
FD, Functional dyspepsia; IBS, Irritable bowel syndrome; UD, Uninvestigated dyspepsia.