tetano
Editor, Senior Moderator
J Virol. 2010 Dec 29. [Epub ahead of print]
Population modeling of influenza A/H1N1 viral kinetics and symptom dynamics.
Canini L, Carrat F.
UPMC Univ Paris 06, UMR-S 707, Paris, F-75012, France; Inserm, UMR-S 707, Paris, F-75012, France; Assistance Publique H?pitaux de Paris, H?pital Saint Antoine, Paris, F-75012, France.
Abstract
Influenza virus kinetics (VK) is used as a surrogate of infectiousness, while the natural history of influenza is described by symptoms dynamics (SD). We used an original viral kinetic/symptom dynamic (VKSD) model to characterize human influenza virus infection and illness, based on a population approach. We combined structural equations and a statistical model to describe intra- and inter-individual variability. The structural equations described influenza, based on the target epithelial cells, the virus, the innate host response, and systemic symptoms. The model was fitted to individual VK and SD data obtained in 44 volunteers experimentally challenged with A/H1N1 influenza virus. Infection and illness parameters were calculated from best-fitted model estimates. We predicted that cytokine level and NK cell activity would peak at days 2.2 and 4.2 after inoculation, respectively. Infectiousness, measured as the area under the VK curve above a viral titer threshold, lasted between 7.0 and 1.3 days and was 15 times lower in participants without systemic symptoms than in those with systemic symptoms (P<0.001). The latent period, defined as the time between inoculation and infectiousness, varied from 0.7 to 1.9 days. The incubation period, defined as the time from inoculation to first symptoms, varied from 1.0 to 2.4 days. Our approach extends previous work by including the innate response and providing realistic estimates of infection and illness parameters, taking into account the strong inter-individual variability. This approach could help to optimize studies of influenza VK and SD, and to predict the effect of antivirals on infectiousness and symptoms.
PMID: 21191031 [PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/21191031
Population modeling of influenza A/H1N1 viral kinetics and symptom dynamics.
Canini L, Carrat F.
UPMC Univ Paris 06, UMR-S 707, Paris, F-75012, France; Inserm, UMR-S 707, Paris, F-75012, France; Assistance Publique H?pitaux de Paris, H?pital Saint Antoine, Paris, F-75012, France.
Abstract
Influenza virus kinetics (VK) is used as a surrogate of infectiousness, while the natural history of influenza is described by symptoms dynamics (SD). We used an original viral kinetic/symptom dynamic (VKSD) model to characterize human influenza virus infection and illness, based on a population approach. We combined structural equations and a statistical model to describe intra- and inter-individual variability. The structural equations described influenza, based on the target epithelial cells, the virus, the innate host response, and systemic symptoms. The model was fitted to individual VK and SD data obtained in 44 volunteers experimentally challenged with A/H1N1 influenza virus. Infection and illness parameters were calculated from best-fitted model estimates. We predicted that cytokine level and NK cell activity would peak at days 2.2 and 4.2 after inoculation, respectively. Infectiousness, measured as the area under the VK curve above a viral titer threshold, lasted between 7.0 and 1.3 days and was 15 times lower in participants without systemic symptoms than in those with systemic symptoms (P<0.001). The latent period, defined as the time between inoculation and infectiousness, varied from 0.7 to 1.9 days. The incubation period, defined as the time from inoculation to first symptoms, varied from 1.0 to 2.4 days. Our approach extends previous work by including the innate response and providing realistic estimates of infection and illness parameters, taking into account the strong inter-individual variability. This approach could help to optimize studies of influenza VK and SD, and to predict the effect of antivirals on infectiousness and symptoms.
PMID: 21191031 [PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/21191031