Volume 12, Number 10—October 2006
Dispatch
Chimpanzee Adenovirus Antibodies in Humans, Sub-Saharan Africa
Table 1
Sera with neutralizing activity to different human and chimpanzee adenoviruses
| Origin | % positive samples (p values)*† |
|||
|---|---|---|---|---|
| AdHu5 | AdC68 | AdC6 | AdC1 | |
| Human controls, United States (n = 50) | 34.0 | 2.0 | 4.0 | 2.0 |
| Human zoo workers, United States (n = 50) | 28.0 | 0 | 0 | 0 |
| Humans, Thailand (n = 200) | 76.5 | 1.5 | 3.0 | 4.0 |
| Humans, Cameroon (n = 405) | 55.8 | 1.7 (0.6764) | 7.9 (0.0045) | 5.4 (0.1248) |
| Humans, Côte d'Ivoire (n = 169) | 95.8 | 9.5 (0.0003) | 10.7 (0.0008) | 3.0 (0.9796) |
| Humans, Nigeria (n = 182) | 89.0 | 4.9 (0.0267) | 18.7 (<0.0001) | 9.3 (0.0045) |
| Chimpanzees, United States (n = 50) | 44.0 | 86.0 (<0.0001) | 92.0 (<0.0001) | 46.0 (<0.0001) |
*p values show statistical difference between percentages of sera positive for neutralizing antibodies to human and chimpanzee adenoviruses. Reactivity of human sera from Cameroon, Côte d'Ivoire, and Nigeria and of chimpanzee sera to the 3 chimpanzee-derived adenoviruses were compared with human sera from the United States (n = 100) and Thailand (n = 200); the last 2 were combined because these countries do not offer natural chimpanzee habitats (similarity of USA and Thailand data for these adenoviruses was statistically confirmed). A logistic regression model was fitted to compare the percentages of samples positive for neutralizing antibodies between different groups. A p value <0.05 was considered statistically significant. All analyses were performed by using SAS version 9.1 logistic procedure (9).
†Virus tested for neutralization with a previously described neutralization assay (10). Samples that neutralized virus at dilutions >1:20 were scored as positive.
