Showing papers by "D. James Nokes published in 2002"
TL;DR: It is established that certain model formulations exhibit characteristics of prototype pattern–forming systems, with pathogen population structure emerging as three possible patterns: incidence is steady and homogeneous; incidence is Steady but heterogeneous; and incidence shows oscillatory dynamics, with travelling waves in strain–space.
Abstract: Many pathogens exhibit antigenic diversity and elicit strain-specific immune responses. This potential for cross-immunity structure in the host resource motivates the development of mathematical models, stressing competition for susceptible hosts in driving pathogen population dynamics and genetics. Here we establish that certain model formulations exhibit characteristics of prototype pattern-forming systems, with pathogen population structure emerging as three possible patterns: (i) incidence is steady and homogeneous; (ii) incidence is steady but heterogeneous; and (iii) incidence shows oscillatory dynamics, with travelling waves in strain-space. Results are robust to strain number, but sensitive to the mechanism of cumulative immunity.
86 citations
TL;DR: After stratification by HIV status, HCV prevalence among women of the general population was identical to that of sex workers, suggesting that HCV sexual transmission is not common in this population and that HIV infection does not enhance susceptibility to HCVSexual transmission.
Abstract: Serum samples (n = 4,593) collected in 1994 as part of a representative household community survey of the population of Addis Ababa who were 0–49 years old were tested for hepatitis C (HCV) antibodies. A third generation ELISA was used for primary screening and a line immunoblot assay for confirmation. HCV antibody prevalence was 0.9% (95% CI, 0.6–1.2%) and higher among HIV-positive compared to HIV-negative individuals (4.5% vs. 0.8%, respectively, P < 0.001). Similar higher prevalence of HCV antibodies was seen among HIV-positive compared to HIV-negative antenatal care attenders (2.9% vs. 0.8%, respectively, P = 0.003, n = 1725), and sex workers (5.3% vs. 1.3%, respectively, P = 0.02, n = 383). Such association between HCV and HIV infection has not been described previously in Africa. After stratification by HIV status, HCV prevalence among women of the general population was identical to that of sex workers, suggesting that HCV sexual transmission is not common in this population and that HIV infection does not enhance susceptibility to HCV sexual transmission. J. Med. Virol. 68:12–17, 2002. © 2002 Wiley-Liss, Inc.
68 citations
TL;DR: Measles seroepidemiology in Taiwan in the 1970s seemed to be more similar to that in a developing country rather than in an industrialized country, and there was a low median age of infection.
11 citations