| 1. | Acquired Immunodeficiency Syndrome (1603 studies) |
| 2. | Adenoviridae Infections (5 studies) |
| 3. | AIDS Dementia Complex (12 studies) |
| 4. | AIDS-Associated Nephropathy (4 studies) |
| 5. | AIDS-Related Complex (276 studies) |
| 6. | AIDS-Related Opportunistic Infections (161 studies) |
| 7. | Arbovirus Infections (6 studies) |
| 8. | Bunyaviridae Infections (1 study) |
| 9. | Burkitt Lymphoma (271 studies) |
| 10. | Central Nervous System Viral Diseases (21 studies) |
| 11. | Chickenpox (13 studies) |
| 12. | Common Cold (4 studies) |
| 13. | Condylomata Acuminata (6 studies) |
| 14. | Congenital Cytomegalovirus (3 studies) |
| 15. | Coronaviridae Infections (1 study) |
| 16. | Coronavirus Infections (1 study) |
| 17. | Cowpox (1 study) |
| 18. | Cytomegalovirus Infections (99 studies) |
| 19. | Cytomegalovirus Retinitis (59 studies) |
| 20. | Deltaretrovirus Infections (21 studies) |
| 21. | Dengue (3 studies) |
| 22. | Dengue Hemorrhagic Fever (2 studies) |
| 23. | DNA Virus Infections (303 studies) |
| 24. | Encephalitis (21 studies) |
| 25. | Encephalitis, Arbovirus (3 studies) |
| 26. | Encephalitis, Herpes Simplex (1 study) |
| 27. | Encephalitis, Viral (10 studies) |
| 28. | Enterovirus Infections (5 studies) |
| 29. | Epstein-Barr Virus Infections (30 studies) |
| 30. | Eye Infections, Viral (61 studies) |
| 31. | Fatigue Syndrome, Chronic (4 studies) |
| 32. | Filoviridae Infections (1 study) |
| 33. | Flaviviridae Infections (64 studies) |
| 34. | Flavivirus Infections (5 studies) |
| 35. | Fowlpox (1 study) |
| 36. | Hantavirus Infections (1 study) |
| 37. | Hantavirus Pulmonary Syndrome (1 study) |
| 38. | Hemorrhagic Fever, Ebola (1 study) |
| 39. | Hemorrhagic Fevers, Viral (3 studies) |
| 40. | Hepadnaviridae Infections (28 studies) |
| 41. | Hepatitis A (3 studies) |
| 42. | Hepatitis B (30 studies) |
| 43. | Hepatitis B, Chronic (14 studies) |
| 44. | Hepatitis C (61 studies) |
| 45. | Hepatitis C, Chronic (22 studies) |
| 46. | Hepatitis D (2 studies) |
| 47. | Hepatitis D, Chronic (1 study) |
| 48. | Hepatitis, Viral, Human (10 studies) |
| 49. | Herpes Genitalis (8 studies) |
| 50. | Herpes Simplex (31 studies) |
| 51. | Herpes Zoster (19 studies) |
| 52. | Herpesviridae Infections (249 studies) |
| 53. | HIV Infections (1494 studies) |
| 54. | HIV Seropositivity (16 studies) |
| 55. | HIV Wasting Syndrome (13 studies) |
| 56. | HIV-Associated Candidiasis (1 study) |
| 57. | HIV-Associated Lipodystrophy Syndrome (1 study) |
| 58. | HTLV-I Infections (23 studies) |
| 59. | Infectious Mononucleosis (1 study) |
| 60. | Influenza (6 studies) |
| 61. | Keratitis, Herpetic (2 studies) |
| 62. | Lentivirus Infections (1493 studies) |
| 63. | Leukemia-Lymphoma, T-Cell, Acute, HTLV-I-Associated (118 studies) |
| 64. | Leukoencephalopathy, Progressive Multifocal (6 studies) |
| 65. | Leukoplakia, Hairy (1 study) |
| 66. | Measles (5 studies) |
| 67. | Mononegavirales Infections (8 studies) |
| 68. | Morbillivirus Infections (5 studies) |
| 69. | Mumps (5 studies) |
| 70. | Myelitis (13 studies) |
| 71. | Nidovirales Infections (1 study) |
| 72. | Opportunistic Infections (163 studies) |
| 73. | Orthomyxoviridae Infections (3 studies) |
| 74. | Papillomavirus Infections (7 studies) |
| 75. | Papovaviridae Infections (2 studies) |
| 76. | Paramyxoviridae Infections (7 studies) |
| 77. | Paraparesis, Tropical Spastic (4 studies) |
| 78. | Picornaviridae Infections (8 studies) |
| 79. | Pneumovirus Infections (2 studies) |
| 80. | Poliomyelitis (5 studies) |
| 81. | Polyomavirus Infections (6 studies) |
| 82. | Postpoliomyelitis Syndrome (4 studies) |
| 83. | Poxviridae Infections (14 studies) |
| 84. | Rabies (3 studies) |
| 85. | Reoviridae Infections (3 studies) |
| 86. | Respiratory Syncytial Virus Infections (2 studies) |
| 87. | Retroviridae Infections (1514 studies) |
| 88. | RNA Virus Infections (1582 studies) |
| 89. | Rotavirus Infections (3 studies) |
| 90. | Rubella (5 studies) |
| 91. | Rubivirus Infections (3 studies) |
| 92. | Rubulavirus Infections (3 studies) |
| 93. | Sarcoma, Kaposi (88 studies) |
| 94. | Severe Acute Respiratory Syndrome (2 studies) |
| 95. | Sexually Transmitted Diseases (1507 studies) |
| 96. | Sexually Transmitted Diseases, Viral (1498 studies) |
| 97. | Skin Diseases, Viral (32 studies) |
| 98. | Slow Virus Diseases (67 studies) |
| 99. | Smallpox (20 studies) |
| 100. | Tick-Borne Diseases (7 studies) |
| 101. | Togaviridae Infections (3 studies) |
| 102. | Tumor Virus Infections (38 studies) |
| 103. | Vaccinia (21 studies) |
| 104. | Viremia (10 studies) |
| 105. | Virus Diseases (1728 studies) |
| 106. | Warts (6 studies) |
| 107. | West Nile Fever (3 studies) |
