Evaluating HIV prevention strategies for populations in key affected groups: the example of Cabo Verde.

OBJECTIVES: We used an individual-based model to evaluate the effects of hypothetical prevention interventions on HIV incidence trajectories in a concentrated, mixed epidemic setting from 2011 to 2021, and using Cabo Verde as an example. METHODS: Simulations were conducted to evaluate the extent to which early HIV treatment and optimization of care, HIV testing, condom distribution, and substance abuse treatment could eliminate new infections (i.e., reduce incidence to less than 10 cases per 10,000 person-years) among non-drug users, female sex workers (FSW), and people who use drugs (PWUD). RESULTS: Scaling up all four interventions resulted in the largest decreases in HIV, with estimates ranging from 1.4 (95 % CI 1.36-1.44) per 10,000 person-years among non-drug users to 8.2 (95 % CI 7.8-8.6) per 10,000 person-years among PWUD in 2021. Intervention scenarios prioritizing FWS and PWUD also resulted in HIV incidence estimates at or below 10 per 10,000 person-years by 2021 for all population sub-groups. CONCLUSIONS: Our results suggest that scaling up multiple interventions among entire population is necessary to achieve elimination. However, prioritizing key populations with this combination prevention strategy may also result in a substantial decrease in total incidence.

A subregional analysis of epidemiologic and genetic characteristics of influenza A(H1N1)pdm09 in Africa: Senegal, Cape Verde, Mauritania, and Guinea, 2009-2010.

During the pandemic 2009 episode, we conducted laboratory-based surveillance in four countries from West Africa: Senegal, Mauritania, Cape Verde, and Guinea. Specimens were obtained from 3,155 patients: 2,264 patients from Senegal, 498 patients from Cape Verde, 227 patients from Mauritania, and 166 patients from Guinea; 911 (28.9%) patients were positive for influenza, 826 (90.7%) patients were positive for influenza A, and 85 (9.3%) patients were positive for influenza B. Among the influenza A positives, 503 (60.9%) positives were H1N1pdm09, 314 (38.0%) positives were H3N2, and 9 (1.1%) positives were seasonal H1N1. The highest detection rate for seasonal influenza viruses (17.1%) occurred in the 5-14 years age group. However, for A(H1N1)pdm09, the detection rate was highest in the 15-24 years age group (35.8%). Based on the present study data, the timeline of detection of A(H1N1)pdm09 viruses in these four countries should be Cape Verde, Guinea, Mauritania, and finally, Senegal. Genetic and antigenic analyses were performed in some isolates.

Delayed 2009 pandemic influenza A virus subtype H1N1 circulation in West Africa, May 2009-April 2010.

To understand 2009 pandemic influenza A virus subtype H1N1 (A[H1N1]pdm09) circulation in West Africa, we collected influenza surveillance data from ministries of health and influenza laboratories in 10 countries, including Cameroon, from 4 May 2009 through 3 April 2010. A total of 10,203 respiratory specimens were tested, of which 25% were positive for influenza virus. Until the end of December 2009, only 14% of all detected strains were A(H1N1)pdm09, but the frequency increased to 89% from January through 3 April 2010. Five West African countries did not report their first A(H1N1)pdm09 case until 6 months after the emergence of the pandemic in North America, in April 2009. The time from first detection of A(H1N1)pdm09 in a country to the time of A(H1N1)pdm09 predominance varied from 0 to 37 weeks. Seven countries did not report A(H1N1)pdm09 predominance until 2010. Introduction and transmission of A(H1N1)pdm09 were delayed in this region.