Two nasal swabs may not be enough to exclude SARS-CoV-2 infection in symptomatic patients.

Abstracts: The spread of COVID-19 (COronaVIrus Disease 2019), due to SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus 2) has taken on dramatic pandemic proportions, affecting over 100 countries in a matter of weeks. Italy has had 237,828 confirmed cases according to the Istituto Superiore di Sanità as of May 13, and 34,448 deaths (1).

Detection of hepatitis C virus-RNA in saliva from chronically HCV-infected patients.

The possibility of the non-parenteral Hepatitis C Virus (HCV) transmission is supported by the demonstration that the actual virus is present in several body fluids, including saliva. From a review of the literature many investigators have found the presence of HCV-RNA in saliva, however, widely contrasting results emerge, with detection rates ranging from 0-100%. To further examine HCV salivary shedding, saliva samples were collected from 46 chronically HCV-infected patients and tested for HCV-RNA and occult blood. Quantification and genotyping of serum HCV-RNA were also carried out for each patient. HCV-RNA was detected in 39.13% of the saliva samples. The viral salivary shedding was significantly related to viraemia levels, serum viral genotype and the presence of salivary occult blood. Our findings indicate that the HCV salivary shedding occurs in about one third of HCV infected patients, but seem to suggest that it is unlikely when the serum viral genotype is 3a. Moreover, blood leakage into the oral cavity is possibly the main source of the salivary HCV-RNA. Although the occurrence of the viral salivary shedding does not necessarily mean that HCV transmission occurs by saliva, our results suggest the need for further investigations into the biological factors possibly involved in HCV mucosal transmission related to both the source and the exposed subjects.

In vitro productive infection of non polarised cervical and rectal biopsies by syncytium-inducing and non syncytium inducing primary HIV-1 isolates.

An in vitro model was used to study the transmission of HIV-1 primary isolates with different biological phenotype to cervical and rectal non polarised bioptic fragments. The method described allowed the productive infection of both cervical and rectal tissues and the virus produced could be propagated onto peripheral blood mononuclear cell cultures. Syncytium-inducing and non-syncytium inducing viral isolates were equally able to produce infection and replication.

Intracellular and cell-free (infectious) HIV-1 in rectal mucosa.

The intestinal mucosa contains most of the total lymphocyte pool and plays an important role in viral transmission, but only slight attention has been given to the immunological and virological aspects of human immunodeficiency virus-1 (HIV-1) infection at this site. In this study, before initiating or changing antiretroviral therapy, paired blood samples and rectal biopsies (RB) were obtained from 26 consecutive HIV-infected subjects. HIV-1 isolation and biological characterization, DNA, and HIV-1 RNA titration were assessed, as were in vitro tumor necrosis factor-alpha (TNF-alpha) and interleukin-beta (IL-1beta) spontaneous production. The rate of HIV-1 isolation from peripheral blood mononuclear cells (PBMCs) and RBs was 75% and 58%, respectively. All RB-derived isolates were nonsyncytium inducing (NSI), independent of the phenotype of blood-derived isolates. Proviral DNA and detectable HIV-1 RNA levels were measured in 100% and 77% of RBs, respectively. A statistical correlation was observed between HIV-1 DNA and HIV-1 RNA levels in rectal mucosa (P = 0.0075), whereas no correlation was found between these levels in blood samples (P > 0.05). Antiretroviral treatment did not seem to influence HIV-1 detection in RBs. Higher levels of in vitro proinflammmatory cytokine production were found in the RBs of most infected patients when compared with healthy controls. Therefore, the rectal mucosa is an important HIV-1 reservoir that demonstrates a discordant viral evolution with respect to blood. Both the virus type and the mucosa pathway of immunoactive substances might have important implications for therapeutic decision-making and monitoring and could influence the bidirectional transmission of HIV-1 in mucosal surfaces.

"In vitro" spontaneous production of B-chemokines by endocervical and endometrial short-term bioptic cultures.

Several studies indicate that HIV-1 is present in the cervico-vaginal tissues and secretions of infected women representing an important determinant of both sexual and mother-to-child transmission. HIV-1 genital shedding is influenced by various factors; among these, proinflammatory cytokines, in particular the beta/C-C chemokine group (RANTES, MIP-1alpha and MIP-1beta), are known to suppress HIV-1 replication and thus might affect both sexual and vertical transmission. This study aimed to standardize a procedure to measure "in vitro" uterine spontaneous chemokine production by means of short-term cultures of endocervical and endometrial bioptic fragments. In most cases, "in vitro" chemokine production was observed in both fragment cultures. These results further confirm that beta/C-C chemokines exist in the female genital tract and that uterine mucosa actively produces basal levels of these immuno-active substances. This method constitutes a useful approach to evaluate cytokine production and expression in the female genital tract, their influence on HIV-1 expression and infectivity in this site, and their possible role in viral transmission.

Frequent detection of HIV-1 RNA but low rates of HIV-1 isolation in cervicovaginal secretions from infected women.

Information regarding the presence of HIV-1 in the female genital tract is necessary to gain insight into the mechanism of HIV-1 heterosexual transmission. Herein, we present the results of a study on virus isolation and HIV-1 RNA detection from cervicovaginal lavage (CVL) samples from 25 HIV-1 seropositive women. Despite detectable levels of HIV-1 RNA in 88% of CVL samples, HIV-1 was isolated in only four (19%) samples. Although HIV-1 shedding in cervicovaginal secretions is a common event at all disease stages, the recovery of infectious virus in cell cultures appears to be rare; this renders viral isolation in studies aimed to evaluate the infectivity of cervicovaginal secretions relatively useless.

Limited secretory-IgA response in cervicovaginal secretions from HIV-1 infected, but not high risk seronegative women: lack of correlation to genital viral shedding.

The presence and antigen specificity of IgG and secretory-IgA (s-IgA) to HIV-1 were evaluated in cervicovaginal lavages (CVL) from 26 infected and 10 high-risk seronegative women. All the seropositive women had detectable IgG recognizing several viral antigens, while a smaller percentage of women demonstrated s-IgA to the virus. In addition, s-IgA were of limited specificity and provided weak reactivities on Immunoblot bands; an almost constant absence of s-IgA to gp120 was also observed. Neither the presence nor the specificity of either IgG or s-IgA to the virus in CVL prevented the shedding of HIV-1 in this body fluid; in fact, viral RNA was detected in all the women studied and the amounts of viral shedding was unrelated to the genital antibody response. On the other hand, none of the high-risk seronegative women had detectable antibodies to HIV-1 in CVL of either the IgG or s-IgA isotype. Our results a) confirm an impairment of mucosal antibody response during HIV-1 infection and suggest that mucosal immunity is not able to prevent viral shedding in the female genital tract and thus cannot modulate the infectivity of genital secretions; aa) do not provide evidence for a mucosal "memory/protective" antibody response in the genital tract of high-risk seronegative women.

Immunological markers in HIV-infected pregnant and non-pregnant women.

OBJECTIVE: To assess the influence of pregnancy on the course of HIV infection by comparing the behaviour of total lymphocyte counts and lymphocyte subsets (CD4(+) and CD8(+) and their ratio) in a cohort of infected pregnant women. SETTING: Tertiary referral centre for high risk obstetrics and infectious diseases in pregnancy. PATIENTS AND METHODS: A prospective study was designed, HIV infected women being enrolled at the beginning of pregnancy and sampled each trimester and in the puerperium. As controls, a group of non-pregnant HIV-infected women, cross-matched for age, risk factors and stage of disease were included and similarly evaluated in the same period. RESULTS: All the parameters, when longitudinally evaluated, were stable during gestation. Compared with non-pregnant subjects, patients had higher CD4(+) counts at the beginning and increased values of total lymphocytes count and subsets during the puerperium. Antepartum and postpartum risk factors such as drug abuse, smoking, antiretroviral therapy, length of gestation, maternal complications and HIV status of the neonate were not influential on the total lymphocytes counts and subsets. DISCUSSION: According to this data, pregnancy per se seems to have a negligible influence over the course of HIV infection, at least as far as immune parameters are concerned.

Phenotypic patterns of HIV-1 clonal populations during highly active antiretroviral therapy (HAART).

Several studies have demonstrated that during HIV-1 infection many different viral clones may co-exist in the same individual. These clones may differ regarding their biological phenotype and may influence both the natural history of infection and the clinical response to antiretroviral therapy. The aim of the present study was to investigate the influences of combination therapies including protease inhibitors (HAART) on the phenotypical pattern of HIV-1 biological clones in peripheral blood mononuclear cells. Viral isolation and biological characterisation of bulk isolates and clonal viral isolates were performed on two AIDS patients, before and after three months of antiretroviral therapy. A decrease of viral load in plasma specimens in association with a change of clonal composition during antiretroviral therapy was observed in both patients during treatment. Before therapy both of the patients had a syncytium inducing (SI) bulk isolate and the majority of the biological clones were characterised as SI. After treatment, the bulk isolates were still SI in both cases, but the majority of biological clones were characterised as non-syncytium inducing (NSI). These results suggest that HIV clonal composition and relative phenotypic pattern undergo different changes not only during the natural course of HIV infection but also while patients are on antiretroviral combination therapy.

Nonproductive human immunodeficiency virus type 1 infection of human fetal astrocytes: independence from CD4 and major chemokine receptors.

Human immunodeficiency virus type 1 (HIV-1) infection of the brain is associated with neurological manifestations both in adults and in children. The primary target for HIV-1 infection in the brain is the microglia, but astrocytes can also be infected. We tested 26 primary HIV-1 isolates for their capacity to infect human fetal astrocytes in culture. Eight of these isolates, independent of their biological phenotype and chemokine receptor usage, were able to infect astrocytes. Although no sustained viral replication could be demonstrated, the virus was recovered by coculture with receptive cells such as macrophages or on stimulation with interleukin-1beta. To gain knowledge into the molecular events that regulate attachment and penetration of HIV-1 in astrocytes, we investigated the expression of several chemokine receptors. Fluorocytometry and calcium-mobilization assay did not provide evidence of expression of any of the major HIV-1 coreceptors, including CXCR4, CCR5, CCR3, and CCR2b, as well as the CD4 molecule on the cell surface of human fetal astrocytes. However, mRNA transcripts for CXCR4, CCR5, Bonzo/STRL33/TYMSTR, and APJ were detected by RT-PCR. Furthermore, infection of astrocytes by HIV-1 isolates with different chemokine receptor usage was not inhibited by the chemokines SDF-1beta, RANTES, MIP-1beta, or MCP-1 or by antibodies directed against the third variable region or the CD4 binding site of gp120. These data show that astrocytes can be infected by primary HIV-1 isolates via a mechanism independent of CD4 or major chemokine receptors. Furthermore, astrocytes are potential carriers of latent HIV-1 and on activation may be implicated in spreading the infection to other neighbouring cells, such as microglia or macrophages.

Reproductive choice in individuals HIV-1 infected in south eastern Italy.

OBJECTIVE: To evaluate the impact of counseling on reproductive choices in seropositive women in South-Eastern Italy. SETTING: University Hospital, Apulia region, South-Eastern Italy, tertiary referral center for high risk obstetrics and infectious diseases. METHODS: Between March 1985 and December 1996, two hundred and twenty-five HIV-infected women, receiving treatment at our clinic for infectious diseases were enrolled. They were all regularly given treatment and counseling and their sexual partners, if negative, tested for HIV-1 antibodies. Their reproductive choices and their attitude toward pregnancy were recorded and analyzed. RESULTS: Seventy-six pregnancies were observed during this period in 76 women. Twenty-one of these women (27.7%) decided to terminate the pregnancy. Women that were intravenous drug users or with a longer history of known seropositivity were more likely to have a termination. A decreasing trend in the request of abortion was observed with time. CONCLUSIONS: The data show that the scenario of HIV-infected women is changing in our setting. As a consequence, many seropositive women deliberately choose to have a pregnancy and factors different from those we expect to be modified by the counseling influence their reproductive choice. They should be taken into account in the management of these women before and during pregnancy.

Detection of human herpesvirus 8 in cervicovaginal secretions and seroprevalence in human immunodeficiency virus type 1-seropositive and -seronegative women.

Epidemiologic studies suggest that human herpesvirus 8 (HHV-8) may be sexually transmitted. To study the potential for HHV-8 transmission through cervicovaginal (CV) secretions, the presence of HHV-8 DNA was investigated by nested polymerase chain reaction in the cellular fraction of CV secretions from 36 human immunodeficiency virus type 1 (HIV-1)-seropositive and 29 HIV-1-seronegative women. The same patients were tested for antibodies to two defined HHV-8 antigens (latency-associated nuclear antigen and open-reading frame 65-encoded structural protein) and for HHV-8 DNA in their peripheral blood mononuclear cells (PBMC). The findings were compared with the rate of HHV-8 detection in semen samples of 20 HIV-1-infected men. HHV-8 DNA was detected in the CV samples from only 1 HHV-8-seropositive AIDS patient, in 3 PBMC samples (1/29 HIV-1-seronegative patients, 1/3 AIDS patients with Kaposi's sarcoma, and 1/19 AIDS patients), and in 1 of 20 semen samples. HHV-8 infection was more common in HIV-1-infected than uninfected women. Thus HHV-8 DNA is only rarely detectable in CV secretions and semen of HHV-8-infected individuals.