Evaluation of PIMA analyzer detecting CD4 cell count of venous and capillary blood in HIV-infected individuals / 中华预防医学杂志

<p><b>OBJECTIVE</b>This study is aimed at evaluating the utility of the portable CD4 analyzers (PIMA).</p><p><b>METHODS</b>The paired finger prick blood (25 µl) and 5 ml venous blood samples were collected from 196 HIV infected patients, who came to Yunnan CDC voluntary counseling and testing (VCT) clinic for CD4 test services, from May to August, 2012. The absolute CD4 cell counts were measured by PIMA (using venous and finger-prick blood) and by Calibur (using venous blood) as the reference. The PIMA and Calibur CD4 results were compared using the Wilcoxon matched-pairs test, and the Spearman's rank correlation coefficients were estimated. The Bland-Altman plots were used to assess the consistency of the two methods.</p><p><b>RESULTS</b>The median absolute CD4 counts of 196 venous blood samples obtained by PIMA and by Calibur were 268 (range:169-403) cells/µl and 302 (range:181-474) cells/µl respectively, which showed significant difference (Z = -7.31, P < 0.01). The median absolute CD4 counts measured by PIMA and by Calibur (using 188 finger-prick and venous blood samples respectively) were 271 (range: 165-450) cells/µl and 304 (range:188-476) cells/µl, which also showed significant difference (Z = -7.60, P < 0.01). The CD4 counts obtained by PIMA CD4 analyzer (using venous and finger-prick blood) showed strong positive correlation with the CD4 counts obtained by the reference method (using venous blood), and the r values were 0.94 and 0.92 respectively (P < 0.01) . The mean biases (limit of agreement) were -38.7 (-210.9-133.5)cells/µl and -45.4 (-221.8-131.0) cells/µl, respectively.Using 350 CD4 counts as the threshold for ART treatment initiation, the sensitivity and specificity of PIMA were 99.1% and 79.3% for venous blood samples, and 97.2%and 78.5% for finger-prick blood samples, respectively.</p><p><b>CONCLUSION</b>The CD4 counts obtained by PIMA are lower than that obtained by Calibur, while the sensitivity is high.</p>

Early detection of HIV infection with Dried Blood Spot testing among infants in Yunnan province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the application of Dried Blood Spot (DBS) testing for early detection of HIV infection among infants.</p><p><b>METHODS</b>All of the infants aged between 6 weeks and 18 months and born by HIV positive mothers from 14 Maternity and Child Health Care Hospitals in Kunming, Dali, Dehong, Lincang of Yunnan province were investigated from 2010 to 2011. By using DBS and Roche HIV-1 DNA test techniques, 286 infants were tested for HIV early diagnosis and compared with HIV antibody results of 18 months infants. DBS from uninfected infants were taken periodically and screened of HIV antibody to find their time of antibody-disappearing. The information of treatment for pregnant women and feeding methods for infants was also investigated.</p><p><b>RESULTS</b>A total of 286 infants were tested with HIV-1 DNA among which 148 infants were male and 138 infants female, and 8 infants were HIV-1 DNA positive and the infection rate was 2.8% (8/286) that was in accord with their antibodies results in 18 months old; the other 278 infants whose HIV-1 DNA was negative was also negative with their antibodies. By following up the antibody test of 143 HIV negative infants the cumulate rates of antibody-disappearing at the age of 6, 9, 12 and 18 months were 14.0% (20/143), 61.5% (88/143), 88.1% (126/143) and 100.0% (143/143), respectively. Among 286 HIV positive pregnant women, the group with anti-viral treatment had a lower rate of HIV infection with their infants that was 2.14% (6/280) while the group without anti-viral treatment had a high rate of HIV infection with their infants that was 33.33% (2/6). There was significantly different in the rates of two groups (P < 0.01). The HIV infection rate of infants fed with milk powder was 2.55% (7/274) and the rate was 8.33% (1/12) with breast milk.</p><p><b>CONCLUSION</b>The HIV-1 DNA detection techniques with DBS sample was effective for the early diagnosis of HIV in infants from 6 weeks to 18 months.</p>

The analysis of human immunodeficiency virus-1 subtypes in Yunnan province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To analyze the geographical distribution and risk factors of HIV-1 subtypes in Yunnan province.</p><p><b>METHODS</b>Blood samples from 1319 HIV positives were collected in Yunnan Province from 2001 to 2006. The nested polymerase chain reaction was used to amplify the gag (p24)-protease fragments from RNA extracted from plasma or sera. The sequences were used for subtype determination by phylogenetic tree analysis.</p><p><b>RESULTS</b>Among 1319 samples studied, the subtypes has been successfully obtained from 644 samples that were constituted of seven subtypes: CRF08_BC, CRF07_BC, CRF07/08_BC, CRF01_AE, C, B' and URFB/C. C/CRF07_BC/CRF08_BC were distributed in the whole province, but CRF01_AE were mainly distributed in the boarding areas with Myanmar such as Dehong, Baoshan, Xishuangbanna and Puer. Moreover, injecting drugs users accounted for 61.6% (270/438) among C/CRF07_BC/CRF08_BC infections, while only 8.5% (15/177) among CRF01_AE infections.</p><p><b>CONCLUSION</b>Our data indicated that at least seven subtypes were identified in Yunnan province, the relationship between subtypes and transmission routes were analyzed, and the geographic difference of subtypes was also observed.</p>

A dynamic analysis on incidence and trend of HIV-1 epidemics among Intravenous Drug Users, attendants at the STD clinics and pregnant women in Yunnan province, China / 中华流行病学杂志

Objective BED-CEIA assay was used in HIV/AIDS surveillance sentinel sites to identify recent HIV-1 infection, to estimate HIV-1 incidence and to understand the epidemic trends in Yunnan province. Methods Serum specimens were collected from IDUs in sentinel sites, attendants in STD clinics and pregnant women under a cross sectional study from 2000 to 2007. Specimens confirmed as HIV-1 positive were tested with BED-CEIA to find resent HIV-1 infection, then the annual HIV-1 incidence for each group was calculated and the trends of HIV-1 incidence observed. Results 144 780 serum specimens were collected and 4932 of them were confirmed as HIV-1 positive. 4678 positive specimens were tested with BED-CEIA and 723 ont of them were identified as recent infections. Specimens from the two years were combined for testing. The average HIV-1 prevalence among IDUs was 18.2 %-26.9 % from 2000 to 2007 and the annual incidence were 14.65%, 6.21%, 4.06%, 2.23% respectively. The average HIV-1 prevalence among attendants in STD clinics was 1.6 %-3.2 % and the annual incidence rates were 1.46 %, 0.76 %, 0.52 %, 0.33 % respectively. The average HIV-1 prevalence among pregnant women was 0.2%-0.5% and the annual incidence rates were 0.16%, 0.11%, 0.10%, 0.09% respectively. Conclusion HIV-1incidence rates among IDUs, STDs and pregnant women showed a steady decease.