Table 1.
Diseases and Facebook support groups by prevalence and type of disease.
| Diseases found on Orphanet (n=4246), n (%) | Facebook support groups (n=6398), n (%) | Diseases with ≥1 group (n=826), n (%) | ||
| Prevalence | ||||
| <1 per 1,000,000 | 2516 (59.3) | 620 (9.7) | 253 (30.6) | |
| 1-9 per 1,000,000 | 150 (3.5) | 452 (7.1) | 85 (10.3) | |
| 1-9 per 100,000 | 188 (4.4) | 1825 (28.5) | 132 (16.0) | |
| 1-9 per 10,000 | 77 (1.8) | 1251 (19.6) | 44 (5.3) | |
| 1-9 per 1000 | 1 (<0.1) | 0 (0.0) | 0 (0.0) | |
| Unknown | 1314 (30.9) | 2250 (35.2) | 312 (37.8) | |
| Disease type | ||||
| Monogenic | 934 (22.0) | 1623 (25.4) | 274 (33.2) | |
| Chromosomal | 145 (3.4) | 655 (10.2) | 51 (6.2) | |
| Mitochondrial | 25 (0.6) | 11 (0.2) | 2 (0.4) | |
| Infectious disease | 2 (<0.1) | 1 (<0.1) | 1 (0.1) | |
| Multigenic or multifactorial | 158 (3.7) | 988 (15.4) | 85 (10.3) | |
| Teratogenic disorder or infectious fetopathy | 22 (0.5) | 68 (1.1) | 4 (0.5) | |
| Micro-/contiguous gene deletion/duplication/triplication | 130 (3.0) | 290 (4.5) | 33 (4.0) | |
| Unclassified | 2830 (66.7) | 2762 (43.2) | 376 (45.5) | |