Diagnostic performance of anti-Zika virus IgM, IgAM and IgG ELISAs during co-circulation of Zika, dengue, and chikungunya viruses in Brazil and Venezuela

Background Serological diagnosis of Zika virus (ZIKV) infection is challenging because of the antibody cross-reactivity among flaviviruses. At the same time, the role of Nucleic Acid Testing (NAT) is limited by the low proportion of symptomatic infections and the low average viral load. Here, we compared the diagnostic performance of commercially available IgM, IgAM, and IgG ELISAs in sequential samples during the ZIKV and chikungunya (CHIKV) epidemics and co-circulation of dengue virus (DENV) in Brazil and Venezuela. Methodology/Principal findings Acute (day of illness 1–5) and follow-up (day of illness ≥ 6) blood samples were collected from nine hundred and seven symptomatic patients enrolled in a prospective multicenter study of symptomatic patients recruited between June 2012 and August 2016. Acute samples were tested by RT-PCR for ZIKV, DENV, and CHIKV. Acute and follow-up samples were tested for IgM, IgAM, and IgG antibodies to ZIKV using commercially available ELISAs. Among follow-up samples with a RT-PCR confirmed ZIKV infection, anti-ZIKV IgAM sensitivity was 93.5% (43/48), while IgM and IgG exhibited sensitivities of 30.3% (10/35) and 72% (18/25), respectively. An additional 24% (26/109) of ZIKV infections were detected via IgAM seroconversion in ZIKV/DENV/CHIKV RT-PCR negative patients. The specificity of anti-ZIKV IgM was estimated at 93% and that of IgAM at 85%. Conclusions/Significance Our findings exemplify the challenges of the assessment of test performance for ZIKV serological tests in the real-world setting, during co-circulation of DENV, ZIKV, and CHIKV. However, we can also demonstrate that the IgAM immunoassay exhibits superior sensitivity to detect ZIKV RT-PCR confirmed infections compared to IgG and IgM immunoassays. The IgAM assay also proves to be promising for detection of anti-ZIKV seroconversions in sequential samples, both in ZIKV PCR-positive as well as PCR-negative patients, making this a candidate assay for serological monitoring of pregnant women in future ZIKV outbreaks.

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Zika Virus Serologic Diagnosis by NS1 ELISA in Curacao

Open Forum Infectious Diseases ◽

10.1093/ofid/ofx163.698 ◽

2017 ◽

Vol 4 (suppl_1) ◽

pp. S302-S303 ◽

Cited By ~ 1

Author(s):

Samantha Manuel ◽

Liane Virginia-Cova ◽

Loubiela Joseph ◽

Chris Roggeveen ◽

Radjin Steingrover

Keyword(s):

Zika Virus ◽

Cross Reactivity ◽

Pregnant Female ◽

Serum Samples ◽

Zikv Infection ◽

Igm Elisa ◽

Pcr Diagnosis ◽

Two Samples ◽

Negative Controls

Abstract Background Zika virus (ZIKV) was introduced in the Caribbean island of Curacao in January 2016. A commercially available ZIKV IgM and IgG ELISA was evaluated on patients that were PCR-positive for ZIKV. Methods ZIKV infection was established by PCR in urine samples. Samples from PCR-positive patients were selected for validation of a ZIKV NS1 IgG and IgM ELISA. Patients with a follow-up sample ≥ 2 weeks after initial presentation were used to assess the sensitivity of the assay. Samples of 15 historical controls with serological evidence of Dengue, Chikungunya or an unrelated viral infection were included to establish specificity and cross-reactivity. Results Fourteen patients with positive ZIKV PCR diagnosis had repeated serum samples drawn ≥ 2 weeks after the initial sample. The combined results of these repeated IgM and IgG tests resulted in a sensitivity of 92%. One pregnant female showed no presence of IgG or IgM in any of the two samples. Testing of the panel of historical ZIKV-negative controls resulted in a specificity of 100% in both the quantitative and semi-quantitative setting of the ELISA. One patient with known high-titers of antibodies against Chikungunya virus in the respective panel displayed borderline reactive results for ZIKV IgG in both quantitative and semi-quantitative setting of the assay. Conclusion In this PCR-positive ZIKV cohort of patients, the newly available ZIKV NS1 ELISA displayed excellent performance characteristics. Cross-reactivity was indicated for Chikungunya in one case. No cross-reactivity was found for Dengue virus infection. One pregnant female showed no signs of developing anti-ZIKV IgM or IgG in this study. In the light of intrauterine pathogenesis, the lack of development of maternal IgG during ZIKV infection is a concern. Disclosures All authors: No reported disclosures.

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Development of Envelope Protein Antigens To Serologically Differentiate Zika Virus Infection from Dengue Virus Infection

Journal of Clinical Microbiology ◽

10.1128/jcm.01504-17 ◽

2017 ◽

Vol 56 (3) ◽

Cited By ~ 16

Author(s):

Lakshmanane Premkumar ◽

Matthew Collins ◽

Stephen Graham ◽

Guei-Jiun Alice Liou ◽

Cesar A. Lopez ◽

...

Keyword(s):

Virus Infection ◽

Dengue Virus ◽

Zika Virus ◽

Envelope Protein ◽

Population Level ◽

Denv Infection ◽

Cross Reactivity ◽

Protein Antigens ◽

Zikv Infection ◽

Serological Tests

ABSTRACT Zika virus (ZIKV) is an emerging flavivirus that can cause birth defects and neurologic complications. Molecular tests are effective for diagnosing acute ZIKV infection, although the majority of infections produce no symptoms at all or present after the narrow window in which molecular diagnostics are dependable. Serology is a reliable method for detecting infections after the viremic period; however, most serological assays have limited specificity due to cross-reactive antibodies elicited by flavivirus infections. Since ZIKV and dengue virus (DENV) widely cocirculate, distinguishing ZIKV infection from DENV infection is particularly important for diagnosing individual cases or for surveillance to coordinate public health responses. Flaviviruses also elicit type-specific antibodies directed to non-cross-reactive epitopes of the infecting virus; such epitopes are attractive targets for the design of antigens for development of serological tests with greater specificity. Guided by comparative epitope modeling of the ZIKV envelope protein, we designed two recombinant antigens displaying unique antigenic regions on domain I (Z-EDI) and domain III (Z-EDIII) of the ZIKV envelope protein. Both the Z-EDI and Z-EDIII antigens consistently detected ZIKV-specific IgG in ZIKV-immune sera but not cross-reactive IgG in DENV-immune sera in late convalescence (>12 weeks postinfection). In contrast, during early convalescence (2 to 12 weeks postinfection), secondary DENV-immune sera and some primary DENV-immune sera cross-reacted with the Z-EDI and Z-EDIII antigens. Analysis of sequential samples from DENV-immune individuals demonstrated that Z-EDIII cross-reactivity peaked in early convalescence and declined steeply over time. The Z-EDIII antigen has much potential as a diagnostic antigen for population-level surveillance and for detecting past infections in patients.

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The proportion of asymptomatic infections and spectrum of disease among pregnant women infected by Zika virus: systematic monitoring in French Guiana, 2016

Eurosurveillance ◽

10.2807/1560-7917.es.2017.22.44.17-00102 ◽

2017 ◽

Vol 22 (44) ◽

Cited By ~ 23

Author(s):

Claude Flamand ◽

Camille Fritzell ◽

Séverine Matheus ◽

Maryvonne Dueymes ◽

Gabriel Carles ◽

...

Keyword(s):

Pregnant Women ◽

Zika Virus ◽

French Guiana ◽

Rt Pcr ◽

Zikv Infection ◽

Younger Women ◽

Adjusted Risk ◽

Adjusted Risk Ratio ◽

Asymptomatic Infections

Zika virus (ZIKV) infection has been associated with complications during pregnancy. Although the presence of symptoms might be a risk factor for complication, the proportion of ZIKV-infected pregnant women with symptoms remains unknown. Following the emergence of ZIKV in French Guiana, all pregnancies in the territory were monitored by RT-PCR and/or detection of ZIKV antibodies. Follow-up data collected during pregnancy monitoring interviews were analysed from 1 February to 1 June 2016. We enrolled 3,050 pregnant women aged 14–48 years and 573 (19%) had laboratory-confirmed ZIKV infection. Rash, arthralgia, myalgia and conjunctival hyperaemia were more frequently observed in ZIKV-positive women; 23% of them (95% confidence interval (CI): 20–27) had at least one symptom compatible with ZIKV infection. Women 30 years and older were significantly more likely to have symptoms than younger women (28% vs 20%). The proportion of symptomatic infections varied from 17% in the remote interior to 35% in the urbanised population near the coast (adjusted risk ratio: 1.6; 95% CI: 1.4–1.9.). These estimates put findings on cohorts of symptomatic ZIKV-positive pregnant women into the wider context of an epidemic with mainly asymptomatic infections. The proportion of symptomatic ZIKV infections appears to vary substantially between populations.

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Test performance evaluation of SARS-CoV-2 serological assays

10.1101/2020.04.25.20074856 ◽

2020 ◽

Cited By ~ 52

Author(s):

Jeffrey D. Whitman ◽

Joseph Hiatt ◽

Cody T. Mowery ◽

Brian R. Shy ◽

Ruby Yu ◽

...

Keyword(s):

Test Performance ◽

Severe Disease ◽

Cross Reactivity ◽

Time Interval ◽

Rt Pcr ◽

Serum Samples ◽

Serological Tests ◽

Full Spectrum ◽

Assay Performance ◽

Lateral Flow Assays

ABSTRACTBackgroundSerological tests are crucial tools for assessments of SARS-CoV-2 exposure, infection and potential immunity. Their appropriate use and interpretation require accurate assay performance data.MethodWe conducted an evaluation of 10 lateral flow assays (LFAs) and two ELISAs to detect anti-SARS-CoV-2 antibodies. The specimen set comprised 130 plasma or serum samples from 80 symptomatic SARS-CoV-2 RT-PCR-positive individuals; 108 pre-COVID-19 negative controls; and 52 recent samples from individuals who underwent respiratory viral testing but were not diagnosed with Coronavirus Disease 2019 (COVID-19). Samples were blinded and LFA results were interpreted by two independent readers, using a standardized intensity scoring system.ResultsAmong specimens from SARS-CoV-2 RT-PCR-positive individuals, the percent seropositive increased with time interval, peaking at 81.8-100.0% in samples taken >20 days after symptom onset. Test specificity ranged from 84.3-100.0% in pre-COVID-19 specimens. Specificity was higher when weak LFA bands were considered negative, but this decreased sensitivity. IgM detection was more variable than IgG, and detection was highest when IgM and IgG results were combined. Agreement between ELISAs and LFAs ranged from 75.8-94.8%. No consistent cross-reactivity was observed.ConclusionOur evaluation showed heterogeneous assay performance. Reader training is key to reliable LFA performance, and can be tailored for survey goals. Informed use of serology will require evaluations covering the full spectrum of SARS-CoV-2 infections, from asymptomatic and mild infection to severe disease, and later convalescence. Well-designed studies to elucidate the mechanisms and serological correlates of protective immunity will be crucial to guide rational clinical and public health policies.

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Antibody responses to SARS-CoV-2 in COVID-19 patients: the perspective application of serological tests in clinical practice

10.1101/2020.03.18.20038018 ◽

2020 ◽

Cited By ~ 44

Author(s):

Quan-xin Long ◽

Hai-jun Deng ◽

Juan Chen ◽

Jie-li Hu ◽

Bei-zhong Liu ◽

...

Keyword(s):

Clinical Practice ◽

Antibody Response ◽

Antibody Test ◽

Fold Increase ◽

Rt Pcr ◽

Serological Tests ◽

Positive Rate ◽

Sequential Samples ◽

Close Contacts

AbstractBackgroundWe aim to investigate the profile of acute antibody response in COVID-19 patients, and provide proposals for the usage of antibody test in clinical practice.MethodsA multi-center cross-section study (285 patients) and a single-center follow-up study (63 patients) were performed to investigate the feature of acute antibody response to SARS-CoV-2. A cohort of 52 COVID-19 suspects and 64 close contacts were enrolled to evaluate the potentiality of the antibody test.ResultsThe positive rate for IgG reached 100% around 20 days after symptoms onset. The median day of seroconversion for both lgG and IgM was 13 days after symptoms onset. Seroconversion of IgM occurred at the same time, or earlier, or later than that of IgG. IgG levels in 100% patients (19/19) entered a platform within 6 days after seroconversion. The criteria of ‘IgG seroconversion’ and ‘> 4-fold increase in the IgG titers in sequential samples’ together diagnosed 82.9% (34/41) of the patients. Antibody test aided to confirm 4 patients with COVID-19 from 52 suspects who failed to be confirmed by RT-PCR and 7 patients from 148 close contacts with negative RT-PCR.ConclusionIgM and IgG should be detected simultaneously at the early phase of infection. The serological diagnosis criterion of seroconversion or the ‘>; 4-fold increase in the IgG titer’ is suitable for a majority of COVID-19 patients. Serologic test is helpful for the diagnosis of SARS-CoV-2 infection in suspects and close contacts.

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Accuracy of the Zika IgM Antibody Capture Enzyme-Linked Immunosorbent Assay from the Centers for Disease Control and Prevention (CDC Zika MAC-ELISA) for Diagnosis of Zika Virus Infection

Diagnostics ◽

10.3390/diagnostics10100835 ◽

2020 ◽

Vol 10 (10) ◽

pp. 835

Author(s):

Moyra Machado Portilho ◽

Laise de Moraes ◽

Mariana Kikuti ◽

Leile Camila Jacob Nascimento ◽

Mitermayer Galvão Reis ◽

...

Keyword(s):

Immunosorbent Assay ◽

Zika Virus ◽

Cross Reactivity ◽

Serological Diagnosis ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

Zikv Infection ◽

Igm Antibody ◽

Convalescent Phase ◽

Antibody Capture

Serological diagnosis of Zika virus (ZIKV) infection is challenging because of antigenic cross-reactivity with dengue virus (DENV). This study evaluated the accuracy of the Zika IgM antibody capture enzyme-linked immunosorbent assay (CDC Zika IgM MAC-ELISA) in differentiating between ZIKV and DENV infections. To determine sensitivity, we used acute- and convalescent-phase sera from 21 patients with RT-PCR-confirmed ZIKV infection. To determine specificity, we used acute- and convalescent-phase sera from 60 RT-PCR-confirmed dengue cases and sera from 23 blood donors. During the acute-phase of the illness, the assay presented a sensitivity of 12.5% (2/16) for samples collected 0–4 days post symptoms onset (DPSO), and of 75.0% (3/4) for samples collected 5–9 DPSO. During the convalescent-phase of the illness, the test sensitivity was 90.9% (10/11), 100% (2/2), and 0% (0/2) for samples obtained 12–102, 258–260, and 722–727 DPSO, respectively. Specificity for acute- and convalescent-phase samples from RT-PCR-confirmed dengue cases was 100% and 93.2%, respectively. Specificity for blood donor samples was 100%. The assay is an accurate method for Zika serological diagnosis and proved to be reliable for use during surveillance and outbreak investigations in settings where ZIKV and DENV cocirculate.

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Zika Virus Infection in Pregnancy: Advanced Diagnostic Approaches in Dengue-Naive and Dengue-Experienced Pregnant Women and Possible Implication for Cross-Reactivity and Cross-Protection

Microorganisms ◽

10.3390/microorganisms8010056 ◽

2019 ◽

Vol 8 (1) ◽

pp. 56 ◽

Cited By ~ 2

Author(s):

Maurizio Zavattoni ◽

Francesca Rovida ◽

Elena Percivalle ◽

Irene Cassaniti ◽

Antonella Sarasini ◽

...

Keyword(s):

Pregnant Women ◽

Zika Virus ◽

Cross Reactivity ◽

Cross Protection ◽

Effector Memory ◽

Congenital Defects ◽

Zikv Infection ◽

Effector Memory T Cells ◽

Diagnostic Approaches

Zika virus (ZIKV) infection has been linked to congenital defects in fetuses and infants, as exemplified by the microcephaly epidemic in Brazil. Given the overlapping presence of Dengue virus (DENV) in the majority of ZIKV epidemic regions, advanced diagnostic approaches need to be evaluated to establish the role of pre-existing DENV immunity in ZIKV infection. From 2015 to 2017, five pregnant women with suspected ZIKV infection were investigated in Pavia, Italy. Among the five pregnant women, three were DENV–ZIKV immunologically cross-reactive, and two were DENV-naïve. Advanced diagnosis included the following: (i) NS1 blockade-of-binding (BOB) ELISA assay for ZIKV specific antibodies and (ii) ELISpot assay for the quantification of effector memory T cells for DENV and ZIKV. These novel assays allowed to distinguish between related flavivirus infections. The three DENV-experienced mothers did not transmit ZIKV to the fetus, while the two DENV-naive mothers transmitted ZIKV to the fetus. Pre-existing immunity in DENV experienced mothers might play a role in cross-protection.

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Update on the Transmission of Zika Virus Through Breast Milk and Breastfeeding: A Systematic Review of the Evidence

Viruses ◽

10.3390/v13010123 ◽

2021 ◽

Vol 13 (1) ◽

pp. 123

Author(s):

Elizabeth Centeno-Tablante ◽

Melisa Medina-Rivera ◽

Julia L. Finkelstein ◽

Heather S. Herman ◽

Pura Rayco-Solon ◽

...

Keyword(s):

Breast Milk ◽

Zika Virus ◽

Mother To Child Transmission ◽

Inclusion Criteria ◽

Rt Pcr ◽

Child Transmission ◽

Zikv Infection ◽

Milk Samples ◽

Clinical Complications ◽

Mother To Child

We systematically searched regional and international databases and screened 1658 non-duplicate records describing women with suspected or confirmed ZIKV infection, intending to breastfeed or give breast milk to an infant to examine the potential of mother-to-child transmission of Zika virus (ZIKV) through breast milk or breastfeeding-related practices. Fourteen studies met our inclusion criteria and inform this analysis. These studies reported on 97 mother–children pairs who provided breast milk for ZIKV assessment. Seventeen breast milk samples from different women were found positive for ZIKV via RT-PCR, and ZIKV replication was found in cell cultures from five out of seven breast milk samples from different women. Only three out of six infants who had ZIKV infection were breastfed, no evidence of clinical complications was found to be associated with ZIKV RNA in breast milk. This review updates our previous report by including 12 new articles, in which we found no evidence of ZIKV mother-to-child transmission through breast milk intake or breastfeeding. As the certainty of the present evidence is low, additional studies are still warranted to determine if ZIKV can be transmitted through breastfeeding.

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DIAGNOSTIC ROLE OF CHEST CT USING CO-RADS CATEGORIZATION IN SARS-COV-2 INFECTION WITH EMPHASIS ON IMPACT OF CT IN PATIENTS WITH DELAYED OR NEGATIVE INITIAL RTPCR TEST

10.36106/ijar/9301921 ◽

2021 ◽

pp. 51-52

Author(s):

Tharani Putta ◽

Kaushik Deconda

Keyword(s):

Diagnostic Performance ◽

Virus Disease ◽

Vital Role ◽

Chest Ct ◽

Lung Involvement ◽

Test Results ◽

Rt Pcr ◽

Diagnostic Role ◽

Pcr Test

BACKGROUND AND OBJECTIVE: Role of chest CT in diagnosis of corona virus disease 2019 (COVID-19) has been controversial. The purpose of this study is to evaluate the diagnostic performance of chest CT when utilizing COVID-19 Reporting and Data System (CO-RADS). METHODOLOGY: Retrospective study including consecutive patients with positive SARS-CoV-2 RT-PCR test (initial or repeat test) and chest CT done in our institute between June and September 2020. Spectrum of CT ndings, CO-RADS score and 25 point CT severity score (CTSS) were recorded. RESULTS: A total of 300 consecutive patients with SARS-CoV-2 infection were included in the analysis. Out of the 168 patients who underwent CT prior to positive RT-PCR result, 125 (74.4%) had CO-RADS 3, 4 or 5 score on chest CT. 32 study patients (10.6%) had initial negative RT-PCR of which 24 (75%) had CO-RADS 4 or 5 score. Of the total patients with CO-RADS 3 to 5 score (227), 20 (8.8%) had severe lung involvement (CTSS 18-25), 83 (36.6%) had moderate lung involvement (CTSS 8-17) and 124 (54.6%) had mild lung involvement (CTSS 1-7). The mean CTSS was 7.9 with mean lobar score being higher in lower lobes (RLL=1.82, LLL=1.78) compared to the upper and middle lobes (RUL=1.61, RML=1.19, LUL=1.53). CONCLUSION:CT using CO-RADS scoring system has good diagnostic performance. In addition to assessing disease severity, it plays a vital role in triage of patients with suspected COVID-19 especially when there is limited availability of SARS-CoV-2 RT-PCR tests, delay in RT-PCR test results or in negative RT-PCR cases when there is high index of clinical suspicion.

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Chest CT as a Complement to RT-PCR to Confirm and Follow-up COVID-19 Patients

Medicinus ◽

10.19166/med.v8i1.3122 ◽

2021 ◽

Vol 8 (1) ◽

pp. 31

Author(s):

Aziza Ghanie Icksan ◽

Muhammad Hafiz ◽

Annisa Dian Harlivasari

Keyword(s):

Chest Ct ◽

Rt Pcr ◽

High Resolution Computed Tomography ◽

X Ray ◽

First Case ◽

Chest X Ray ◽

Polymerase Chain

Background : The first case of COVID-19 in Indonesia was recorded in March 2020. Limitation of reverse-transcription polymerase chain reaction (RT-PCR) has put chest CT as an essential complementary tool in the diagnosis and follow up treatment for COVID-19. Literatures strongly suggested that High-Resolution Computed Tomography (HRCT) is essential in diagnosing typical symptoms of COVID-19 at the early phase of disease due to its superior sensitivity (97%) compared to chest x-ray (CXR).The two cases presented in this case study showed the crucial role of chest CT with HRCT to establish the working diagnosis and follow up COVID-19 patients as a complement to RT-PCR, currently deemed a gold standard.

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