Association between recent methamphetamine use, antiretroviral therapy and HIV viral load; a mediation analysis from a cohort of HIV positive persons who inject drugs in Hai Phong, Vietnam.

BACKGROUND: There has been a significant increase in methamphetamine use among persons who use drugs in Vietnam in the last 5-10 years. We examined the degree to which adherence to antiretroviral therapy (ART) mediates the relationship between recent methamphetamine use and unsuppressed HIV viral load among people who inject drugs (PWID) in Hai Phong, Vietnam. METHODS: We recruited PWID from October 2016-October 2018 and enrolled HIV positive PWID into a cohort, with up to three years of total follow-up. We assessed relationships among recent methamphetamine use frequency, ART adherence and unsuppressed HIV viral load. Mediation analysis was used to estimate the total and natural direct effects of recent methamphetamine use on unsuppressed HIV viral load and the indirect effect proportion. RESULTS: We enrolled 792 HIV seropositive PWID into the cohort; approximately 75.9% reported high/perfect ART adherence at baseline and 81.3% were virally suppressed. In mediation analysis, the total effect for the association between methamphetamine use and unsuppressed HIV viral load (1000 copies/mL) was 3.94 (95% CI: 1.95, 7.96); the natural direct effect was 2.14 (95% CI: 1.29, 3.55); the proportion mediated by self-reported ART adherence was 0.444. Similar results were found when examining lower unsuppressed HIV viral load cutpoints of 250 copies/mL and 500 copies/mL. CONCLUSIONS: Methamphetamine use is associated with unsuppressed HIV viral load among PWID despite high levels of ART adherence. Further research is needed to better understand these relationships, with emphasis on potential biological pathways that may interact with ART.

Impact of Infection Control on Prevalence of Surgical Site Infections in a Large Tertiary Care Hospital in Haiphong City.

Few point prevalence surveys (PPS) have been conducted in Vietnam on Surgical Site Infections (SSI) or antimicrobial use in surgery. The objective of this study was to evaluate the PPSs of SSI before and after implementation of antibiotic stewardship programs (ASP) and infection control (IC) in a Vietnamese tertiary care hospital. ASP and IC practices were implemented in operating rooms and the orthopedic department, including antibiotic training, skin preparation, hand hygiene, gloves and sterile instruments, and SSIs risk factors. A PPS of SSIs and antimicrobial use was performed in January 2016 according to methods from the Centers for Disease Control and Prevention, before ASP and IC, and in December 2019. Information recorded included surgical data, antibiotic prophylaxis, microorganisms, and SSI risk factors. Skin preparation compliance assessed preoperative washing and antisepsis. SSI prevalence was 7.8% in 2016 versus 5.4% in 2019 (p = 0.7). The use of prophylactic antibiotics decreased from 2016 to 2019. A third-generation cephalosporin was prescribed more than 48 h after surgery for most patients. Skin preparation compliance increased from 54.4% to 70.5% between assessments. The decreased SSI, although non-statistically significant, warrants continuing this program. Vietnamese hospitals must provide comprehensive IC education to healthcare workers to address the prevention of SSI and establish IC policies.

Assessment and Simplification of Treatment Eligibility Among Patients With Chronic Hepatitis B Infection in Vietnam.

BACKGROUND: Treatment eligibility and the accuracy of its simplified criteria have been poorly documented in patients with chronic hepatitis B virus (HBV) infection worldwide, especially in low- and middle-income countries. METHODS: From a cohort of HBV-infected patients in Vietnam, we assessed the proportion of patients eligible for treatment using the national guidelines based on reference tests (HBV DNA quantification and FibroScan); and the accuracy of simplified treatment criteria free from HBV DNA and FibroScan (Treatment Eligibility in Africa for the Hepatitis B Virus [TREAT-B] score and simplified World Health Organization [WHO] criteria) to select patients for antiviral therapy using the national guidelines as a reference. RESULTS: We analyzed 400 consecutive treatment-naïve HBV-monoinfected patients: 49% males, median age 38 years (range, 18-86), 32% hepatitis B e antigen-positive, median HBV DNA 4.8 log10 IU/mL (undetectable -8.4), median FibroScan 5.3 kPa (3.0-67.8), and 25% having significant liver fibrosis including 12% with cirrhosis. Of these, 167 (42%) fulfilled treatment criteria according to national guidelines. Using the national criteria as a reference, the performance of TREAT-B to select patients for treatment was high (area under the receiver operating characteristic [AUROC], 0.89 [95% confidence interval 0.87-0.92]) with a sensitivity of 74.3% and a specificity of 88.4%. In a subset of patients with 2 alanine aminotransferase measurements over a 6-month period (n = 89), the AUROC of TREAT-B was significantly higher than that of the simplified WHO criteria (P < .001). CONCLUSIONS: Our study suggests that a large proportion of patients with chronic HBV infection require antiviral therapy in Vietnam. Compared with the simplified WHO criteria free from HBV DNA quantification, TREAT-B is a better alternative to easily indicate treatment eligibility and might help scale up treatment intervention in Vietnam.

Towards HCV elimination among people who inject drugs in Hai Phong, Vietnam: study protocol for an effectiveness-implementation trial evaluating an integrated model of HCV care (DRIVE-C: DRug use & Infections in ViEtnam-hepatitis C).

INTRODUCTION: In Vietnam, people who inject drugs (PWID), who are the major population infected by hepatitis C virus (HCV), remain largely undiagnosed and unlinked to HCV prevention and care despite recommended universal hepatitis C treatment. The data on the outcomes of HCV treatment among PWID also remain limited in resource-limited settings. The DRug use & Infections in ViEtnam-hepatitis C (DRIVE-C) study examines the effectiveness of a model of hepatitis C screening and integrated care targeting PWID that largely uses community-based organisations (CBO) in Hai Phong, Vietnam. In a wider perspective, this model may have the potential to eliminate HCV among PWID in this city. METHODS AND ANALYSIS: The model of care comprises large community-based mass screening, simplified treatment with direct-acting antivirals (DAAs) and major involvement of CBO for PWID reaching out, linkage to care, treatment adherence and prevention of reinfection. The effectiveness of DAA care strategy among PWID, the potential obstacles to widespread implementation and its impact at population level will be assessed. A cost-effectiveness analysis is planned to further inform policy-makers. The enrolment target is 1050 PWID, recruited from the DRIVE study in Hai Phong. After initiation of pan-genotypic treatment consisting of sofosbuvir and daclatasvir administrated for 12 weeks, with ribavirin added in cases of cirrhosis, participants are followed-up for 48 weeks. The primary outcome is the proportion of patients with sustained virological response at week 48, that will be compared with a theoretical expected rate of 70%. ETHICS AND DISSEMINATION: The study was approved by Haiphong University of Medicine and Pharmacy's Ethics Review Board and the Vietnamese Ministry of Health. The sponsor and the investigators are committed to conducting this study in accordance with ethics principles contained in the World Medical Association's Declaration of Helsinki (Ethical Principles for Medical Research Involving Human Subjects). Informed consent is obtained before study enrolment. The data are anonymised and stored in a secure database. The study is ongoing. Results will be presented at international conferences and submitted to international peer-review journals. TRIAL REGISTRATION NUMBER: NCT03537196.

Confirmation of HCV viremia using HCV RNA and core antigen testing on dried blood spot in HIV infected peoples who inject drugs in Vietnam.

BACKGROUND: Nucleic acid tests performed on blood samples collected on Dried Blood Spot (DBS) and detection of HCV core antigen (HCVcAg) are two approaches that may facilitate access to HCV diagnosis in low and middle incomes countries. In this study we evaluate HCV RNA and HCV antigen testing on DBS in HIV/HCV co-infected peoples who inject drugs in Vietnam. METHOD: One hundred and four HIV/HCV seropositive patients managed in outpatient care at the Haiphong Viet Tiep hospital were included in this study from February to March, 2014 (ANRS 12262 study). RESULTS: Eighty-six subjects were tested positive for HCV RNA in serum, median (IQR): 6.9 log10 IU/ml (5.6-7.4 log10 IU/ml). Genotypes consisted of 57 G1 (69%), 3 G3 (4%), and 22 G6 (27%). HCV RNA was detected on DBS specimens in 79 out 86 subjects with chronic hepatitis C (sensitivity 92.5%; 95% CI: 85.1-96.9%). HCV RNA level on DBS and serum was moderately correlated (r = 0.24; p = 0.05) suggesting a degradation of HCV RNA due to transportation and storage conditions. HCVcAg was detected in 75/86 dB specimens (sensitivity: 87.2%; 95% CI: 78.3-93.4%), with a strong positive relationship between DBS HCVcAg and serum HCV RNA levels (r = 0.80; P < 0.0001). CONCLUSIONS: Quantification of HCVcAg on DBS appears to benefit from substantial stability under prolonged storage conditions but with a lower analytical sensitivity compared to DBS HCV RNA testing. Detection of HCV RNA on DBS is an interesting approach for confirming viral replication in HCV seropositive persons but the impact of pre-analytical conditions on the integrity of HCV RNA needs to be controlled.

Psychiatric Comorbidities among People Who Inject Drugs in Hai Phong, Vietnam: The Need for Screening and Innovative Interventions.

The objective of this study is to describe psychiatric comorbidities, associated factors, and access to psychiatric assessment and care in a cohort of people who inject drugs (PWID) in Hai Phong, Vietnam. Mental health was assessed after 12 months' follow-up using the Mini International Neuropsychiatric Interview questionnaire (MINI 5.0.0). PWID medical history, drug use, and sociodemographic and clinical characteristics were also collected. Among 188 PWID who participated in the assessment, 48 (25.5%) had at least one psychiatric disorder and 19 (10.1%) had 2 or more psychiatric disorders. The most common current psychiatric disorders were major depressive episode (12.2%) and psychotic disorder (4.8%), reaching 10.1% for the latter when lifetime prevalence was considered. Females were more likely than males to have at least one psychiatric disorder, a major depressive disorder, or an anxiety disorder. Methamphetamine use was associated with an increased risk of presenting a lifetime psychotic syndrome. Problematic alcohol consumption was associated with an increased risk of having at least one psychiatric disorder. Psychiatric comorbidities are frequent among PWID in Vietnam. These results highlight the need for routine assessment and innovative interventions to address mental health needs among PWID. Community-based interventions targeting mental health prevention and care should be strongly supported.

Increased Methamphetamine Use among Persons Who Inject Drugs in Hai Phong, Vietnam, and the Association with Injection and Sexual Risk Behaviors.

Methamphetamine use has increased significantly in Southeast Asia in the last 5-10 years, but there is little research on risk behaviors associated with the increase in this region. We evaluate injection and sexual risk behaviors associated with current methamphetamine use among heterosexual persons who inject drugs (PWID) in Hai Phong, Vietnam. We recruited 1336 PWID and assessed associations between methamphetamine use, injection and sexual risk behaviors, stratified by HIV serostatus. There were several statistically significant associations between methamphetamine use and sexual risk behaviors among HIV-positive PWID, but we did not find any associations between methamphetamine use and injection risk behaviors. Methamphetamine may increase the likelihood of PWID transmitting HIV to non-injecting primary sexual partners, as it can reduce ART adherence and can lead to weakening of the immune system and increased HIV viral loads. All participants were injecting heroin, and methamphetamine use may interfere with opiate use treatment. Public health efforts should focus on the large increase in methamphetamine use and the associated sexual risk behaviors. Emphasis on sexual risk behavior, particularly among those who are HIV-positive, in conjunction with continued monitoring of ART adherence and HIV viral loads, is critical.

Intravenous heroin use in Haiphong, Vietnam: Need for comprehensive care including methamphetamine use-related interventions.

BACKGROUND: The aim of this study was to describe patterns among people who inject drugs (PWID), risk-related behaviours and access to methadone treatment, in order to design a large-scale intervention aiming to end the HIV epidemic in Haiphong, Vietnam. METHODS: A respondent-driven sampling (RDS) survey was first conducted to identify profiles of drug use and HIV risk-related behaviour among PWID. A sample of PWID was then included in a one-year cohort study to describe access to methadone treatment and associated factors. RESULTS: Among the 603 patients enrolled in the RDS survey, 10% were female, all were injecting heroin and 24% were using methamphetamine, including 3 (0.5%) through injection. Different profiles of risk-related behaviours were identified, including one entailing high-risk sexual behaviour (n=37) and another involving drug-related high-risk practices (n=22). High-risk sexual activity was related to binge drinking and methamphetamine use. Among subjects with low sexual risk, sexual intercourse with a main partner with unknown serostatus was often unprotected. Among the 250 PWID included in the cohort, 55.2% initiated methadone treatment during the follow-up (versus 4.4% at RDS); methamphetamine use significantly increased. The factors associated with not being treated with methadone after 52 weeks were fewer injections per month and being a methamphetamine user at RDS. CONCLUSION: Heroin is still the main drug injected in Haiphong. Methamphetamine use is increasing markedly and is associated with delay in methadone initiation. Drug-related risks are low but sexual risk behaviours are still present. Comprehensive approaches are needed in the short term.

High Proportion of HIV-HCV Coinfected Patients with Advanced Liver Fibrosis Requiring Hepatitis C Treatment in Haiphong, Northern Vietnam (ANRS 12262).

RATIONALE AND AIMS: Screening and treatment for chronic hepatitis C are very limited in Vietnam and clinical data on HCV-related liver disease in HIV-coinfected people are almost inexistent. This study aimed to assess the severity of liver fibrosis and its risk factors in HIV-HCV coinfected patients in Haiphong, Northern Vietnam. METHODS: A cross-sectional study was conducted at a HIV outpatient clinic. Consecutive HIV treated adults with positive HCV serology completed a standardised epidemiological questionnaire and had a comprehensive liver assessment including hepatic elastography (Fibroscan®, Echosens). RESULTS: From February to March 2014, 104 HIV-HCV coinfected patients receiving antiretroviral therapy (ART) were prospectively enrolled (99 males, median age: 35.8 (32.7-39.6) years, median CD4 count: 504 (361-624) /mm3. Of them, 93 (89.4%) had detectable HCV RNA (median 6.19 (4.95-6.83 Log10 IU/mL). Patients were mainly infected with genotypes 1a/1b (69%) and genotypes 6a/6e (26%). Forty-three patients (41.3%) had fibrosis ≥F2 including 24 patients (23.1%) with extensive fibrosis (F3) and/or cirrhosis (F4). In univariate analysis, excessive alcohol consumption, estimated time duration from HCV infection, nevirapine and lopinavir-based ARV regimen and CD4 nadir were associated factors of extensive fibrosis/cirrhosis. Alcohol abuse was the only independent factor of extensive fibrosis in multivariate analysis. Using Fibroscan® as a gold standard, the high thresholds of AST-to-platelet ratio index (APRI) and fibrosis-4 score (FIB-4) had very good performances for the diagnosis of extensive fibrosis/cirrhosis (Se: 90 and 100%, Sp:84 and 81%, AUROCs = 0.93, 95%CI: 0.86-0.99 and 0.96 (0.92-0.99), respectively). CONCLUSION: In this study, nearly 25% of HIV-HCV coinfected patients successfully treated with ART have extensive fibrosis or cirrhosis, and therefore require urgently HCV treatment.

Prospects for ending the HIV epidemic among persons who inject drugs in Haiphong, Vietnam.

BACKGROUND: To examine the prospects for "ending the HIV epidemic" among persons who inject drugs (PWID) in Haiphong, Vietnam. Reaching an incidence of <0.5/100 person-years at risk (PY) was used as an operational definition for "ending the epidemic." METHODS: A respondent driven sampling study of 603 PWID was conducted from September to October 2014. Current heroin use (verified with urine testing and marks of injection) was an eligibility requirement. A structured questionnaire was administered by trained interviewers to obtain demographic, drug use, and risk behavior data; HIV counseling and testing and HCV testing was also conducted. Two methods (by assuming all new injectors were HIV negative at first injection and by slope of prevalence by years injecting) were used for estimating HIV among persons injecting for <5 years ("new injectors"). Comparisons were made to the HIV epidemic among PWID in New York City and modeling of the HIV epidemic in Can Tho province. RESULTS: HIV prevalence was 25% in 2014, down from 68% in 2006 and 48% in 2009; overall HCV prevalence in the study was 67%. Among HIV seropositive PWID, 33% reported receiving antiretroviral treatment. The great majority (83%) of subjects reported pharmacies as their primary source of needles and syringes and self-reported receptive and distributive syringe sharing were quite low (<6%). Estimating HIV incidence among non-MSM male new injectors with the assumption that all were HIV negative at first injection gave a rate of 1.2/100 person-years (95% CI -0.24, 3.4). Estimating HIV incidence by the slope of prevalence by years injecting gave a rate of 0.8/100 person-years at risk (95% CI -0.9, 2.5). CONCLUSIONS: The current HIV epidemic among PWID in Haiphong is in a declining phase, but estimated incidence among non-MSM new injectors is approximately 1/100 person-years and there is a substantial gap in provision of ART for HIV seropositives. Scaling up interventions, particularly HIV counseling and testing and antiretroviral treatment for all seropositive PWID, should accelerate the decline. Ending the epidemic is an attainable public health goal.

Hepatocyte pathway alterations in response to in vitro Crimean Congo hemorrhagic fever virus infection.

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus responsible for hemorrhagic manifestations and multiple organ failure, with a high mortality rate. In infected humans, damage to endothelial cells and vascular leakage may be a direct result of virus infection or an immune response-mediated indirect effect. The main target cells are mononuclear phagocytes, endothelial cells and hepatocytes; the liver being a key target for the virus, which was described as susceptible to interferon host response and to induce apoptosis. To better understand the early liver cell alterations due to virus infection, the protein profile of in vitro CCHFV-infected HepG2 cells was analyzed using two quantitative proteomic approaches, 2D-DIGE and iTRAQ. A set of 243 differentially expressed proteins was identified. Bioinformatics analysis (Ingenuity Pathways Analysis) revealed multiple host cell pathways and functions altered after CCHFV infection, with notably 106 proteins related to cell death, including 79 associated with apoptosis. Different protein networks emerged with associated pathways involved in inflammation, oxidative stress and apoptosis, ubiquitination/sumoylation, regulation of the nucleo-cytoplasmic transport, and virus entry. Collectively, this study revealed host liver protein abundances that were modified at the early stages of CCHFV infection, offering an unparalleled opportunity of the description of the potential pathogenesis processes and of possible targets for antiviral research.

Immunoproteomic identification of antigenic salivary biomarkers detected by Ixodes ricinus-exposed rabbit sera.

Ixodes ricinus, the primary vector of tick-borne disease in Europe, is currently expanding its distribution area and its activity in many countries. Antibody responses to tick salivary antigens have been proposed as an alternative marker of exposure to tick bites. However, the identification of the I. ricinus corresponding antigens remains elusive. Using rabbits artificially exposed to I. ricinus and 2 other European tick species (Rhipicephalus sanguineus and Dermacentor reticulatus) as controls, a cross-comparison of IgG profiles was performed against protein salivary gland extracts (pSGE) from these 3 tick species using immunoblots. Immunoblot analysis highlighted a singularity in the immune patterns according to tick species exposure and pSGE antigen source. Two protein bands were detected against I. ricinus pSGE only in rabbits exposed to I. ricinus bites. An immunoproteomic approach based on a fluorescence detection method was developed to unambiguously identify corresponding antigenic spots on 2-D gels. Among the unique I. ricinus salivary antigenic proteins detected by sera from rabbits exposed to this tick species, I. ricinus calreticulin was identified. Although tick calreticulin was previously proposed as a potential antigenic marker following exposure to ticks (particularly in North American tick species), the present study suggested that Ixodes calreticulin does not appear to be cross-recognized by the 2 other tick genera tested. Additional experiments are needed to confirm the use of I. ricinus calreticulin salivary protein as a potential discriminant antigenic biomarker to Ixodes tick exposure.

Identification of salivary antigenic markers discriminating host exposition between two European ticks: Rhipicephalus sanguineus and Dermacentor reticulatus.

To succeed blood meal, ticks inject salivary proteins to mammalian hosts, eliciting an antibody response against these foreign antigens. Although this immune response has been proposed as a surrogate marker of exposure to tick bites, identification of the corresponding antigens remains elusive. For this aim, a comparison by immunoblots of the kinetic IgG responses to protein salivary gland extracts from two European tick species, Rhipicephalus sanguineus or Dermacentor reticulatus, in rabbits was performed. A singularity in the immune patterns was observed according to rabbit exposure status and depending on the antigen source. Six and five bands were found specifically associated to R. sanguineus and to D. reticulatus exposures, respectively. The identity of these salivary antigenic proteins was determined using an original immunoproteomic approach. The utilization of these tick salivary proteins as biomarker candidates to discriminate R. sanguineus and/or D. reticulatus tick exposure or to develop anti-tick vaccines is discussed.

Assessment of Anopheles salivary antigens as individual exposure biomarkers to species-specific malaria vector bites.

BACKGROUND: Malaria transmission occurs during the blood feeding of infected anopheline mosquitoes concomitant with a saliva injection into the vertebrate host. In sub-Saharan Africa, most malaria transmission is due to Anopheles funestus s.s and to Anopheles gambiae s.l. (mainly Anopheles gambiae s.s. and Anopheles arabiensis). Several studies have demonstrated that the immune response against salivary antigens could be used to evaluate individual exposure to mosquito bites. The aim of this study was to assess the use of secreted salivary proteins as specific biomarkers of exposure to An. gambiae and/or An. funestus bites. METHODS: For this purpose, salivary gland proteins 6 (SG6) and 5'nucleotidases (5'nuc) from An. gambiae (gSG6 and g-5'nuc) and An. funestus (fSG6 and f-5'nuc) were selected and produced in recombinant form. The specificity of the IgG response against these salivary proteins was tested using an ELISA with sera from individuals living in three Senegalese villages (NDiop, n = 50; Dielmo, n = 38; and Diama, n = 46) that had been exposed to distinct densities and proportions of the Anopheles species. Individuals who had not been exposed to these tropical mosquitoes were used as controls (Marseille, n = 45). RESULTS: The IgG responses against SG6 recombinant proteins from these two Anopheles species and against g-5'nucleotidase from An. gambiae, were significantly higher in Senegalese individuals compared with controls who were not exposed to specific Anopheles species. Conversely, an association was observed between the level of An. funestus exposure and the serological immune response levels against the f-5'nucleotidase protein. CONCLUSION: This study revealed an Anopheles salivary antigenic protein that could be considered to be a promising antigenic marker to distinguish malaria vector exposure at the species level. The epidemiological interest of such species-specific antigenic markers is discussed.

Determinants of pre-exposure rabies vaccination among foreign backpackers in Bangkok, Thailand.

Important variations were observed regarding the proportion of backpackers seeking information about travel-associated diseases before departing for Thailand. The main determinants were nationality, reason for travel and age. Sources of information used by travelers varied substantially according to nationality. Moreover, significant differences were recorded regarding pre-exposure vaccination rates against rabies. Having British or Irish citizenship and seeking advice from travel clinic specialists or friends were the strongest and most significant determinants of rabies vaccination history. A significant relationship between vaccine cost and vaccination coverage was also evidenced.

Protective measures against acute respiratory symptoms in French pilgrims participating in the Hajj of 2009.

Among a cohort of 274 French pilgrims participating in the 2009 Hajj, 77.4% used hand disinfectant, 89.8% used disposable handkerchiefs, and 79.6% used face masks; 97.4% were vaccinated against seasonal flu, 5.8% against H1N1, and 31.4% against pneumococcus. Influenza vaccine and face mask use did not significantly reduce respiratory symptoms.

Improving the diagnostic efficiency of H1N1 2009 pandemic flu: analysis of predictive clinical signs through a prospective cohort.

In late June 2009, we set up a dedicated flu-like illness outpatient consultation in the Infectious Diseases and Tropical Medicine department of Marseille university hospital to detect the new A/H1N1 pandemic influenza and to contain efficiently the A/H1N1 infected patients. For 3 months, we compiled data corresponding to a total of 307 patients who presented with a flu-like syndrome. 31 of them were positive for H1N1 pandemic flu through real-time RT-PCR (rRT-PCR); among them, 19 were positive for a rapid influenza detection test (RIDT). We report here the significant clinical characteristics of A/H1N1 pandemic flu patients compared with other flu-like illnesses, which were used to improve the predictive value of the diagnosis in the current epidemiological situation. We found that regardless of the prevalence of A/H1N1 positive cases in the suspected patients, the absence of cough rejects the diagnosis of A/H1N1 infection in 100% of cases. Among patients referred for flu-like illness, those with cough should be tested for A/H1N1 by RIDT. In the current situation, the PPV and NPV of RIDT for H1N1 reached 90.5% and 95.8 %, respectively. It is important to notice that the 2 RIDT-positive that were negative for H1N1 were seasonal H3N2 influenza indicating that specificity and PPV of RIDT for all influenza was 100%. Therefore, positive RIDT does not require rRT-PCR confirmatory test. Only negative RIDT should be tested with rRT-PCR assay. Respecting this algorithm would have saved up to 70,000 Euros ( 100.000 USD) for the 307 patients and would have resulted in a significant gain of time to transmit the laboratory results to the clinical ward.