Increased prevalence and stable clustering rate of HIV-1 transmitted drug resistance strains after 'treat-all' in a megacity of China.

OBJECTIVES: The 'treat-all' strategy was implemented in Shenzhen, China in 2016. The effect of this extensive treatment on transmitted drug resistance (TDR) of HIV is unclear. METHODS: TDR analysis was performed, based on the partial HIV-1 pol gene obtained from the newly reported HIV-1 positive cases from 2011 to 2019 in Shenzhen, China. The HIV-1 molecular transmission networks were inferred to analyse the spread of TDR. Logistic regression was used to identify the potential risk factors with TDR mutations (TDRMs) to cluster. RESULTS: A total of 12 320 partial pol sequences were included in this study. The prevalence of TDR was 2.95% (363/12 320), which increased from 2.57% to 3.52% after 'treat-all'. The TDR prevalence was increased in populations with the characteristics of CRF07_BC, being single, educated to junior college level and above, MSM and male. The sensitivities of viruses to six antiretroviral drugs were decreased. The clustering rate of TDRMs remained stable, and the sequences in the three drug resistance transmission clusters (DRTCs) were mainly found during 2011-16. CRF07_BC and CRF55_01B were the factors associated with TDRMs clustering in the networks. CONCLUSIONS: The 'treat-all' strategy might have contributed to a small increase in TDR, while most of the TDRMs were distributed sporadically, which implies that the 'treat-all' strategy is helpful for the control of TDR in high-risk populations.

Antibody response to the third dose of inactivated COVID-19 vaccine in people living with HIV (PLWH): A longitudinal cohort.

The immunogenicity induced by the third dose of inactivated coronavirus disease 2019 (COVID-19) vaccines in people living with HIV (PLWH) is unclear, and relevant literature is extremely scarce. It is important to add evidence on the humoral immune response induced by the third dose of inactivated COVID-19 vaccine in PLWH. We collected peripheral venous blood for spike receptor binding domain-protein specific immunoglobulin G (S-RBD-IgG) antibody tests at 28 days after the second dose (T1 ), 180 days after the second dose (T2 ) and 35 days after the third dose (T3 ) of inactivated COVID-19 vaccines in PLWH. The differences in S-RBD-IgG antibody levels and specific seroprevalence among T1 , T2 , and T3 time periods were analyzed, and the effects of age, vaccine brand, and CD4+ T cell count on the levels and specific seroprevalence of S-RBD-IgG antibody induced by the third dose in PLWH were examined. The third dose of inactivated COVID-19 vaccines induced strong S-RBD-IgG antibody responses in PLWH. The levels and specific seroprevalence of S-RBD-IgG antibody were significantly higher than those at 28 and 180 days after the second dose and were not affected by vaccine brand or CD4+ T cell count. Younger PLWH produced higher levels of S-RBD-IgG antibody. The third dose of inactivated COVID-19 vaccine showed good immunogenicity in PLWH. It is necessary to popularize the third dose in the PLWH population, especially PLWH who do not respond to two doses of inactivated COVID-19 vaccines. Meanwhile, the durability of the protection provided by the third dose in PLWH must be continuously monitored.

Primary resistance to integrase inhibitors in Shenzhen.

OBJECTIVES: In recent years, integrase strand transfer inhibitor (INSTI)-containing regimens have been increasingly adopted in treatment for HIV/AIDS and promoted as non-occupational post-exposure prophylaxis in China. This study aims to describe the prevalence of resistance to integrase and drug resistance mutations (DRMs) among ART-naive patients in Shenzhen, China. METHODS: Serum samples and demographic information were collected from newly reported ART-naive patients in Shenzhen in 2020. The study sequenced the coding sequence of the HIV-1 integrase gene and determined the DRMs.​. RESULTS: In this study, 1682 newly reported cases were included and 1071 of them were successfully sequenced finally. The prevalence of primary drug resistance was 1.77%, with 19 samples showing varying degrees of resistance to INSTIs. The study detected six major DRMs in 16 individuals and eight accessory DRMs in 24 individuals. The prevalence of transmitted drug resistance (TDR) mutations was 1.21%, with five transmitted mutations detected in 13 individuals. The prevalence of drug resistance to raltegravir and elvitegravir was statistically higher than to bictegravir, cabotegravir and dolutegravir. CONCLUSIONS: The prevalence of INSTI resistance in Shenzhen in 2020 was relatively high. ​Continued surveillance for resistance to INSTIs is recommended and treatment regimens should be adopted based on the pattern of resistance to INSTIs. ​Dolutegravir or bictegravir is first recommended when considering INSTIs as treatment regimens.

Estimating Changes in Population Size and Behavioral Characteristics in Men Who Have Sex With Men Between 2014 and 2019: Longitudinal Study.

BACKGROUND: Men who have sex with men (MSM) are at high risk for HIV infection. Accurate estimation of the population size and monitoring the risk sexual behavioral change of MSM is of great importance to develop targeted HIV prevention and interventions. OBJECTIVE: The goal of the research was accurate estimation of the population size and monitoring the risk sexual behavioral change of MSM. METHODS: Street interception investigation methods were conducted among males aged 16 years and older in selected sites in Shenzhen in 2014 and 2019. A population survey was used to estimate the population size of MSM. Logistic regression analysis was applied to evaluate the difference in behavioral characteristics in MSM from 2014 to 2019. RESULTS: In this study, we surveyed 10,170 participants in 2014, of whom 448 (4.41%, 95% CI 4.01%-4.80%) participants were men who have ever had sex with another man (MSMe) and 229 (2.25%, 95% CI 1.96%-2.54%) were men who had sex with another man in the previous 6 months (MSMa). A total of 10,226 participants were surveyed in 2019, of which 500 (4.90%, 95% CI 4.47%-5.31%) and 208 (2.03%, 95% CI 1.76%-2.31%) participants were MSMe and MSMa, respectively. The results showed that the population size of MSM who are active (MSMa) in Shenzhen was 155,469 (2.29%, 95% CI 2.28%-2.30%) in 2014 and 167,337 (2.05%, 95% CI 2.04%-2.06%) in 2019. It was estimated that there were about 12,005,445 (2.04%, 95% CI 2.04%-2.04%) MSMa in China in 2019. Compared with 2014, the MSMa in 2019 were more likely to seek sex partners through mobile phone apps and less likely to have male and female sex partners in addition to having inconsistent condom use and more than 6 sex partners in the previous 6 months. CONCLUSIONS: In Shenzhen, the proportion of MSMa among the general male population was lower in 2019 than in 2014, and the prevalence of HIV risk behavior was reduced in 2019. Although the preferred platform to find male sex partners among MSM has changed, intervention with high-HIV risk MSM could still help to reduce HIV risk behaviors among the whole MSM group. Because MSM prefer to seek sex partners through mobile phone apps, further study is needed to strengthen internet interventions with high-HIV risk MSM to curb the spread of HIV.

IgG Antibody Responses and Immune Persistence of Two Doses of BBIBP-CorV Vaccine or CoronaVac Vaccine in People Living with HIV (PLWH) in Shenzhen, China.

The purpose of this study was to preliminarily evaluate the immunogenicity and immune persistence of inactivated SARS-CoV-2 vaccines in PLWH in the real world. We collected blood samples from 132 PLWH aged 18−59 years who were vaccinated with two doses of BBIBP-CorV vaccine (Sinopharm) or CoronaVac vaccine (SinoVac) at 28 ± 7 days and 180 ± 20 days the after second dose, to detect the level of Spike receptor binding domain-protein specific IgG (S-RBD-IgG) by using chemiluminescence. We found that the BBIBP-CorV vaccine or the CoronaVac vaccine induced lower S-RBD-IgG antibody seropositivity rates and levels in PLWH than in healthy controls (HCs). The BBIBP-CorV vaccine or the CoronaVac vaccine induced lower humoral immune responses in PLWH, having lower CD4+T cell counts (<350 cells/µL) compared to PLWH, and having higher CD4+T cell counts (≥350 cells/µL) after a second dose of vaccination. The BBIBP-CorV vaccine or the CoronaVac vaccine induced lower S-RBD-IgG antibody levels in PLWH, having CD4+T cell counts ≥350 cells/µL compared to HCs. No negative effects were observed in terms of the CD4+T cell counts and HIV RNA viral load (VL) of PLWH after vaccination. Ninety-nine PLWH and eighty-three HCs completed a second blood collection for testing; we found a statistically significant decrease in the humoral immune response both in PLWH and HCs from 28 days to 180 days after a second dose of BBIBP-CorV vaccine or CoronaVac vaccine. The S-RBD-IgG antibody induced by the BBIBP-CorV vaccine or the CoronaVac vaccine declined faster in the PLWH population than in the healthy population, and two doses of the BBIBP-CorV vaccine or the CoronaVac vaccine may not be enough to provide PLWH with persistent immunity against SARS-CoV-2. It is necessary for PLWH to be prioritized for a third dose over the healthy population, but the immunogenicity of the third dose of the homologous or heterologous vaccine requires further study.

Use of HIV Post-Exposure Prophylaxis Among Men Who Have Sex With Men in Shenzhen, China: A Serial Cross-Sectional Study.

HIV postexposure prophylaxis (PEP) has been prescribed to non-occupational people in recent years, but the implementation of PEP in China is still unclear. This study sought to examine the PEP use rate and factors associated with PEP in Men who have sex with men (MSM). We recruited HIV-negative MSM through offline methods from 2018 to 2020 in Shenzhen, China. Overall, PEP use increased from 3.92% to 2018, 5.73% in 2019, and 10.29% in 2020. Among 2833 participants who reported their most recent questionnaire, factors associated with PEP use included residence in Shenzhen less than 1 year, sexual intercourse with women, preferred way of finding sexual partners in MSM venues, multiple sexual partners (≥ 2), condom use, lubricant use, viagra use, less use of rush popper, HIV-related services and interest in initiating Pre-exposure prophylaxis (PrEP). The implementation of the PEP plan should focus on the groups that may be at risk of HIV infection and their continued risky behaviours. For the inappropriate use of PEP, PEP publicity should guide MSM to choose regular hospitals and strengthen HIV testing before and after PEP.

Characterization of Three Novel HIV-1 Second-Generation Recombinants (CRF01_AE/CRF07_BC) Identified in Shenzhen, China.

The prevalence of recombinant forms has greatly enhanced HIV-1 genetic diversity. Under co-circulation of major epidemic HIV-1 strains (CRF01_AE and CRF07_BC) in China, more CRF01_AE and CRF07_BC as the backbone of HIV-1 second-generation recombinants (SGRs) are also emerging. In this study, we identified three similar novel HIV-1 SGR strains composed of CRF01_AE and CRF07_BC from HIV-1 positive individuals in Shenzhen, China. Near full-length genome phylogenetic and recombinant analysis confirmed that these unique recombination forms were CRF01_AE and CRF07_BC strains recombined. Further subregion phylogenetic analysis indicated that all CRF01_AE fragments were from CRF01_AE cluster 4 prevalent among men who have sex with men, and all subtype B and C fragments derived from CRF07_BC. The emergence of novel recombinants of CRF01_AE/CRF07_BC indicates the increased genetic diversity of the HIV epidemic in Shenzhen. It is necessary to monitor HIV-1 SGR strains among high-risk populations for the epidemic dynamics of HIV-1 in Shenzhen, China.

Low rate of pre-exposure prophylaxis and post-exposure prophylaxis uptake and high prevalence of transmitted drug resistance among newly diagnosed primary HIV infections in Shenzhen, China: a real-world retrospective study.

BACKGROUND: Understanding the characteristics of newly diagnosed primary human deficiency virus-1 (HIV-1) infection in the context of the post-antiretroviral therapy era and HIV drug prophylaxis is essential for achieving the new target of 95-95-95-95 by 2025. This study reported the characteristics of newly diagnosed primary HIV-1 infection in Shenzhen. METHODS: This is a real-world retrospective study. Eighty-seven newly diagnosed primary HIV-1-infected patients were recruited from January 2021 to March 2022 at the Third People's Hospital of Shenzhen. Demographic, epidemiological, diagnostic, drug resistance, and medical data were described and analyzed. RESULTS: Overall, 96.6% (84/87) of the newly identified primary HIV-1-infected patients were male, including 88.5% (77/87) men have sex with men (MSM), with a median age of 29.0 years (Q1-Q3: 24.0-34.0 years); of these, 85.1% (74/87) reported high-risk sexual behaviors with casual partners. The rate of condom usage was only 28.7% (25/87). The overall rate of pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP) was 8.0% (7/87, including 4 PrEP and 3 PEP cases) around the potential exposure, although 41.4% of the patients had prior awareness of such interventions. Moreover, only 19.5% (17/87) had previously used PrEP or PEP. Of those, 58.8% (10/17) of the patients obtained drugs from the internet, and only 35.3% (6/17) reported good compliance. A total of 54.0% (47/87) of subjects were diagnosed by the HIV nucleic acid test. Acute retroviral syndrome appeared in 54.0% (47/87) of patients. The prevalence of transmitted drug resistance (TDR) mutation was 33.9% (19/56), including 6 (10.7%) against nucleoside reverse transcriptase inhibitor (NRTI) plus non-nucleoside reverse transcriptase inhibitor (NNRTI), 8 (14.3%) against NNRTI, and 5 (8.9%) against protease inhibitor (PI) only. CONCLUSIONS: Owing to the low utilization rate and incorrect usage of PrEP and PEP, massive efforts are needed to promote HIV-preventive strategies in the MSM population. The extremely high prevalence of TDR mutation in this population implies the need for future pretreatment drug resistance surveillance.

Impact of HIV-1 CRF55_01B infection on the evolution of CD4 count and plasma HIV RNA load in men who have sex with men prior to antiretroviral therapy.

BACKGROUND: CRF55_01B is a newly identified HIV-1 circulating recombinant form originated from MSM in China. However, its impact on the disease progression and transmission risk has not been investigated. This study aimed to determine the impact of CRF55_01B infection on viral dynamics and immunological status so as to provide scientific evidence for further control and prevention effort on CRF55_01B. Linear mixed effect models were applied to evaluate CD4 cell count decline and viral load increase by subtype. RESULTS: Of the 3418 blood samples, 1446 (42.3%) were CRF07_BC, 1169 (34.2%) CRF01_AE, 467 (13.7%) CRF55_01B, 249 (7.3%) type B, and 87 (2.5%) other subtypes (CRF_08BC, CRF_01B, C). CRF55_01B had become the third predominant strain since 2012 in Shenzhen, China. CRF55_01B-infected MSM showed lower median of CD4 count than CRF07_BC-infected MSM (349.5 [IQR, 250.2-474.8] vs. 370.0 [IQR, 278.0-501.0], P < 0.05). CRF55_01B infection was associated with slower loss of CD4 count than CRF01_AE (13.6 vs. 23.3 [cells/µl]¹/²/year, P < 0.05)among MSM with initial CD4 count of 200-350 cells/µl. On the other hand, those infected with CRF55_01B showed higher median plasma HIV RNA load (5.4 [IQR, 5.0-5.9]) than both CRF01_AE (5.3 [IQR, 4.8-5.7], P < 0.05) and CRF07_BC (5.0 log10 [IQR, 4.5-5.5], P < 0.001) at the initiation of antiretroviral therapy. Furthermore, the annual increasing rate of viral load for CRF55_01B infection was significantly higher than that of CRF07_BC (2.0 vs. 0.7 log10 copies/ml/year, P < 0.01). CONCLUSIONS: The relatively lower CD4 count and faster increase of plasma HIV RNA load of CRF55_01B-infected MSM without antiretroviral therapy suggest that CRF55_01B may lead to longer asymptomatic phase and higher risk of HIV transmission. Strengthened surveillance, tailored prevention strategies and interventions, and in-depth research focusing on CRF55_01B are urgently needed to forestall potential epidemic.

HIV-1 Infection Alters the Viral Composition of Plasma in Men Who Have Sex with Men.

Altered gut virome and expanded abundance of certain viruses were found in HIV-1-infected individuals. It remains largely unknown how plasma virus composition changes during HIV-1 infection and antiretroviral therapy (ART). We performed viral metagenomic analysis on viral particles enriched from human plasma from 101 men who have sex with men (MSM) with or without HIV-1 infection and whether or not on ART and compared the differences in the plasma virome. An increased plasma viral abundance of main eukaryotic viruses was observed during HIV-1 infection in MSM, especially in AIDS patients (CD4+ T cell counts of <200). Anellovirus, pegivirus and hepatitis B virus (HBV) were the most abundant blood-borne viruses detected among MSM and HIV-1-infected individuals, and anellovirus and pegivirus were closely related to HIV-1 infection. High diversity of anelloviruses was found mostly in HIV-1-infected MSM, and their abundance was positively correlated with the HIV-1 viral load, but negatively correlated with both CD4+ T cell counts and CD4+/CD8+ ratio; in contrast, the abundance of pegivirus showed opposite correlations. ART usage could restore the plasma virome toward that of HIV-1-negative individuals. These data showed an expansion in abundance of certain viruses during HIV-1 infection, indicating the higher risk of shedding some blood-borne viruses in these individuals. These investigations indicate that both anellovirus and pegivirus may play certain roles in HIV disease progression.IMPORTANCE Though an increasing number of studies have indicated the existence of an interaction between the virome and human health or disease, the specific role of these plasma viral components remains largely unsolved. We provide evidence here that an altered plasma virome profile is associated with different immune status of HIV-1 infection. Specific resident viruses, such as anellovirus and pegivirus, may directly or indirectly participate in the disease progression of HIV-1 infection. These results can help to determine their clinical relevance and design potential therapies.

Trends of HIV/Syphilis/HSV-2 seropositive rate and factors associated with HSV-2 infection in men who have sex with men in Shenzhen, China: A retrospective study.

OBJECTIVES: To analyze the trends of HIV/syphilis/HSV-2 seropositive rate and explore the related factors with HSV-2 infection to provide the basis for adjusting STD intervention strategies and formulating prevention and control measures among MSM in Shenzhen. METHODS: Time-location sampling was conducted among MSM in Shenzhen in 2012, 2014, 2016, and 2018. Data on demographics, sexual behaviors and the laboratory test results of HIV, syphilis, HSV-2 were collected. The χ2 trend test was used to analyze the trends of HIV/syphilis/HSV-2 seropositive rate. The binary logistic regression model was used to explore the factors associated with HSV-2 infection. RESULTS: The seropositive rate of HIV fell significantly from 15.9% in 2012 to 8.7% in 2018 (Ptrend = 0.003), syphilis seropositive rate was significantly decreased from 20.4% in 2012 to 14.8% in 2018 (Ptrend = 0.025), HSV-2 seropositive rate had no significant change (16.7% in 2012 to 14.0% in 2018; Ptrend = 0.617). In principal component logistic regression analysis showed that FAC1_1 (X1 = Ever had sex with female, X2 = Gender of first sexual partner, X3 = Marital status, X4 = Age group), FAC2_1 (X5 = Education, X6 = Monthly income (RMB), X7 = Frequency of condom use in anal sex with men in the past 6 months), and FAC4_1 (X9 = History of STDs) were significantly associated with HSV-2 infection. CONCLUSIONS: The seropositive rates of HIV and syphilis have dropped significantly but are still high. HSV-2 seropositive rate had no significant change and maintained a high level. It is necessary to continue strengthening HIV and syphilis interventions among MSM in Shenzhen. HSV-2 detection and intervention are urgently required for MSM, which might be another effective biological strategy further to control the HIV epidemic among MSM in Shenzhen.

Molecular surveillance of HIV-1 newly diagnosed infections in Shenzhen, China from 2011 to 2018.

OBJECTIVES: Shenzhen is suffering severe HIV epidemic. No systematic surveillance on high risk populations, HIV genetic diversity, transmitted drug resistance (TDR) and molecular transmission clusters (MTCs) have been reported yet. In this study, we described them based on newly diagnosed HIV positive cases from 2011 to 2018 in Shenzhen city, China. METHODS: Plasma samples of newly reported HIV positive cases in Shenzhen, China were collected from 2011 to 2018. The HIV pol gene was amplified and sequenced for subtyping, genetic characterization, TDR and phylogenetic analysis. Demographic and risk characteristics associated with transmitted drug resistance-associated mutations (TDRAMs) and MTCs were explored by using logistic regression analyses. RESULTS: 10,378 HIV pol sequences were successfully obtained from newly diagnosed patients with available background information. The most prevalent HIV-1 subtype was CRF07_BC (40.92%). CRF07_BC, CRF55_01B and URFs increased across years. Total TDR was 6.02% during 2011 to 2018. CRF01_AE, CRF08_BC, CRF55_01B and subtype B were more likely to be associated with TDRAMs than CRF07_BC. 4460 (42.98%) patients were infected with strains included in MTCs. Patients younger than 30 and over 50 years were more likely to cluster. CONCLUSIONS: The prevalence of HIV-1 drug resistance and molecular transmission clusters in Shenzhen should raise a high alert. Interventions targeting on patients with strains locating in MTCs should be considered to improve prevention effect in Shenzhen.

Genomic characterization of a new CRF01_AE/CRF07_BC case from a MSM patient in Guangdong, China.

The CRF01_AE and CRF07_BC clades dominate the human immunodeficiency virus (HIV) epidemics in China. Both clades have been identified in the men who have sex with men (MSM) population in Guangdong province, raising a serious concern of possible complex recombination events ahead. Here, we report the first case of CRF01_AE/CRF07_BC recombinant sampled from a MSM patient in southern China. The genomic structure of this case is a mosaic with some regions resembling the CRF01_AE and CRF07_BC clades. Our phylogenetic analyses show that the two parental lineages of this recombinant virus were mainly found in the MSM population. This case has a different genomic composition compared with other recombinants descended from the same parental clades CRF01_AE and CRF07_BC. Our finding suggests that the MSM populations have become a hotspot for expanding viral diversity through the viral recombination mechanism. Therefore, further epidemiologic surveillance and monitoring should be conducted within the MSM populations to help advance our knowledge of viral transmission mechanisms. Additionally, these measures will serve to enhance the control and prevention of HIV/acquired immunodeficiency syndrome in China.

Independent epidemic patterns of HIV-1 CRF01_AE lineages driven by mobile population in Shenzhen, an immigrant city of China.

Shenzhen, a city with >12 million migrant population, may play a key role in the spread of human immunodeficiency virus (HIV)-1 in China. The transmission dynamics of CRF01_AE, a predominant subtype in Shenzhen, is a good model to characterize the impact of human mobility on HIV-1 epidemic locally and nationally. We used phylodynamic and phylogeographic methods to estimate the viral transmission dynamics and migration trajectory of variable lineages based on 1,423 CRF01_AE sequences in Shenzhen sampled between 2006 and 2015. Eleven lineages of CRF01_AE were detected in Shenzhen. Of those, four main lineages originated during the 1990s. Their basic viral reproduction number (R 0) ranged 1.96-3.92. The effective viral reproduction number (R e ) of two lineages prevalent among heterosexuals/people who inject drugs had reduced <1 at the end of sampling, and the main sources were the intra-provincial immigrants (72 per cent) for one and local residents of Shenzhen (91 per cent) for another. Within two lineages among men who have sex with men (MSM), R e had been above or close to 1 at the end of sampling, and the immigrants from Jiangxi/Shaanxi and Hubei as sources accounted for 93 per cent and 68 per cent of all viral migration events, respectively. Moreover, no obvious recipients were found throughout the viral migration history for any lineage. Our findings demonstrate that HIV epidemic is declining in Shenzhen, which coincided with the initiation of the interventions during the 2000s. However, the obvious differences of the epidemic patterns between lineages emphasize the importance of further targeting interventions and continued molecular tracing, focusing on high-risk transmission sources among MSM.

Viral RNA level, serum antibody responses, and transmission risk in recovered COVID-19 patients with recurrent positive SARS-CoV-2 RNA test results: a population-based observational cohort study.

Managing recovered COVID-19 patients with recurrent-positive SARS-CoV-2 RNA test results is challenging. We performed a population-based observational study to characterize the viral RNA level and serum antibody responses in recurrent-positive patients and evaluate their viral transmission risk. Of 479 recovered COVID-19 patients, 93 (19%) recurrent-positive patients were identified, characterized by younger age, with a median discharge-to-recurrent-positive length of 8 days. After readmission, recurrent-positive patients exhibited mild (28%) or absent (72%) symptoms, with no disease progression. The viral RNA level in recurrent-positive patients ranged from 1.8 to 5.7 log10 copies/mL (median: 3.2), which was significantly lower than the corresponding values at disease onset. There are generally no significant differences in antibody levels between recurrent-positive and non-recurrent-positive patients, or in recurrent-positive patients over time (before, during, or after recurrent-positive detection). Virus isolation of nine representative specimens returned negative results. Whole genome sequencing of six specimens yielded only genomic fragments. 96 close contacts and 1,200 candidate contacts of 23 recurrent-positive patients showed no clinical symptoms; their viral RNA (1,296/1,296) and antibody (20/20) tests were negative. After full recovery (no longer/never recurrent-positive), 60% (98/162) patients had neutralizing antibody titers of ≥1:32. Our findings suggested that an intermittent, non-stable excretion of low-level viral RNA may result in recurrent-positive occurrence, rather than re-infection. Recurrent-positive patients pose a low transmission risk, a relatively relaxed management of recovered COVID-19 patients is recommended.

Two-year cross-sectional studies reveal that single, young MSMs in Shenzhen, China are at high risk for HIV infection.

BACKGROUND: Shenzhen City is a rapidly growing area with a large number of floating populations, thus making it difficult to control HIV. Serial cross-sectional studies are helpful for the prediction of epidemiological tendency. In this study, two parallel cross-sectional studies were compared to explore changes in HIV epidemiology in Shenzhen, China. METHODS: Two hundred and fifty newly reported HIV-positive cases were randomly selected in Shenzhen City in 2013 and 2015. Socio-demographical information was collected with informed consent. Full-length gag and partial pol genes were amplified using nested RT-PCR followed by sequencing and phylogenetic analysis. The genotypes of anti-HIV drug resistance were also analyzed. The characteristics of the HIV epidemics of 2013 and 2015 were compared to identify patterns. RESULTS: The proportion of single, young MSMs dramatically increased in 2015 compared to 2013. Many subtypes, including CRF07_BC (36.4%), CRF01_AE (34.1%), CRF55_01B (10.2%), B (6.4%), CRF08_BC (3.4%), CRF59_01B (0.9%), C (0.7%), D (0.2%), CRF68_01B (0.2%), CRF67_01B (0.2%), and unique recombinant forms (URFs, 7.3%), were identified. Close phylogenetic relationships between strains prevalent in Shenzhen and other areas of China was observed. No epidemic cluster confined to single, young MSMs was identified. 0.4 and 2.8% of the strains contained transmitted drug-resistant mutations in 2013 and 2015, respectively. CONCLUSION: Although the interval period is short, changes in HIV epidemiology in Shenzhen City are distinct. Frequent surveillance of HIV epidemics in Shenzhen City is thus necessary. Single, young MSMs have become a high-risk population for HIV infection and should be considered as focus population for HIV prevention and behavior intervention in Shenzhen City.

Near Full-Length Genomic Sequences of Two Novel HIV-1 Recombinant Forms Identified in Shenzhen, China.

Most HIV subtypes prevalent in China can be found in Shenzhen, including CRF07_BC, CRF01_AE, CRF08_BC, CRF55_01B, and subtype B. Multiple subtypes spreading in the same population always lead to the emergence of unique recombinant strains. Here, we report two unique recombinant forms (SZ44LS7251 and SZ95LS8027) of HIV-1 identified in a heterosexual population. Recombinant analyses were fulfilled based on the near full-length genomes. Both strains comprise subtypes B, C, and CRF01_AE. Phylogenetic analysis reveals that SZ44LS7251 is the second generation recombination originated from CRF55_01B andCRF07_BC, whereas SZ95LS8027 comprises CRF01_AE and CRF07_BC.The emergence of second generation recombination of HIV with complicated genomic structures supposed that high ratio of super infections or coinfections might happen in the Shenzhen area.

The dynamics of the HIV epidemic among men who have sex with men (MSM) from 2005 to 2012 in Shenzhen, China.

HIV-1 epidemics among MSM are a major public health concern in China, especially in large cities. This study sought to better understand the dynamics of HIV molecular epidemiology among MSM in Shenzhen, a rapidly developing city with over 13.8 million people. HIV-1 pol sequences were obtained from 996 (53.5%) of 1862 HIV-infected MSM and 403(9.0%) of 4498 heterosexuals and injection drug users in Shenzhen, China from 2005-2012. Eight HIV-1 subtypes and some inter-subtype recombinants were identified among sampled MSM with CRF07_BC (39.1%) and CRF01_AE (35.1%) being the most predominant. From 2006 to 2012, the prevalence of CRF07_BC and CRF55_01B rapidly increased, while the prevalence of subtypes B and CRF01_AE gradually decreased. The genetic distances within CRF07_BC and CRF55_01B groups were significantly lower than within CRF01_AE and B groups. The vast majority (90.3%) of HIV-1 infected MSM in Shenzhen were migrants who came from 31 of the 34 provinces of China, and these migrants had significantly different HIV-1 subtype distributions from the local MSM. This study highlighted the importance of CRF07_BC and migrants in the changing HIV epidemic among MSM in China, and provides a molecular epidemiology framework for understanding how HIV-1 epidemics can change in large cities with diverse risk groups.