P.028 The utility of vomit as a specimen in the investigation of norovirus outbreaks

Abstract

Purpose: The occurrence of HIV-1 dual infections in Amsterdam, The Netherlands, was examined from 2003–2007 to investigate whether or not HIV-1 dual infections are increasing as the number of HIV-1 infected individuals increased here over this time period. Methods: All first HIV-1 genotyping sequences determined between 2003 and 2007 were retrieved and examined for the number of degenerate base codes in the RT fragment. From a total of 73 patients with a degenerate base code count of > 33, a fragment of the V3-V4 region of the env gene was amplified, cloned and sequenced to verify the presence of a HIV-1 dual infection. Dual infections were counted for each year investigated. Results: No significant change in incidence of dual infections was seen in our patient population selected upon the degenerate base count in the HIV-1 genotyping sequence from 2003 till 2007. The frequency of HIV-1 dual infections varied between 1.0%–2.8%/year, with no significant trend in time (p = 0.49). Based upon the number of patients with a high degenerate base code count, an increase in dual infections was expected in 2006 and 2007, but this was not observed. HIV-1 dual infections were similar to HIV-1 single infections in The Netherlands in distribution by risk group, gender and subtype. Conclusion: HIV-1 dual infections in The Netherlands are not increasing from 2003 to 2007 although the HIV-1 infected population is expanding in this period.