Evaluación de ensayos ultramicroanalíticos para la detección de anticuerpos contra el SARS-CoV-2 / Evaluation of ultramicroanalytic assays to detect antibodies against SARS-CoV-2

Introducción: En el presente trabajo se muestran los resultados de la validación de los ensayos serológicos in vitro para la detección de anticuerpos IgM, IgG y anticuerpos totales contra el SARS-CoV-2 UMELISA SARS-CoV-2 IgM, UMELISA ANTI-SARS-CoV-2 y UMELISA SARS-CoV-2 IgG desarrollados por el Centro de Inmunoensayo (CIE). Métodos: Se utilizaron paneles de muestras de suero de individuos negativos y de casos confirmados de COVID-19 para determinar el desempeño analítico de cada ensayo. Resultados: La especificidad clínica de los ensayos UMELISA SARS-CoV-2 IgM, UMELISA ANTI-SARS-CoV-2 y UMELISA SARS-CoV-2 IgG fue del 100 por ciento en todos los ensayos y la especificidad analítica fue de 100 por ciento para los dos primeros ensayos y del 93,1 por cientopara el último. La sensibilidad clínica fue de 64,3, 80,8 y 97,5 por ciento, respectivamente. El valor predictivo positivo fue de 100 por ciento en todos los ensayos, en tanto que el negativo osciló entre 83,3 y 95,2 por ciento. La concordancia fluctuó entre 92,4 y 96,9 por ciento y el índice kappa de todos los ensayos fue muy bueno. La sensibilidad de los ensayos se incrementó a 82,76, 96,5 y 100 por ciento, respectivamente, en las muestras de suero colectadas con más de 14 días de iniciado el cuadro clínico. Conclusiones: Los ensayos demostraron una elevada sensibilidad y especificidad, lo que permite contar con herramientas basadas en una tecnología desarrollada en Cuba que posibilita la realización de estudios serológicos, vigilancia epidemiológica y de otro tipo, incluyendo los relacionados con vacunas en una plataforma con amplia distribución nacional(AU)

Introduction: This paper shows the results obtained in the validation of in vitro serological assays to detect IgM, IgG antibodies, and total antibodies against SARS-CoV-2 UMELISA SARS-CoV-2 IgM, UMELISA ANTI-SARS-CoV-2 and UMELISA SARS-CoV-2 IgG developed by the Immunoassay Center. Methods: Panels of serum samples from negative and COVID-19 confirmed patients were used to determine the analytical performance of each assay. Results: UMELISA SARS-CoV-2 IgM, UMELISA ANTI-SARS-CoV-2 and UMELISA SARS-CoV-2 IgG assays demonstrated 100 percent clinical specificity for all assays; and 100 percent analytical specificity for the first two assays, and 93.1 percent for the last one. Clinical sensitivity was 64.3 percent, 80.8 percent and 97.5 percent, respectively. The positive predictive value was 100 percent in all assays, while the negative predictive value ranged from 83.3 percent to 95.2 percent. Concordance varied from 92.4 percent to 96.9 percent, and kappa index in every assay was very good. Assays sensitivity increased to 82.7 percent, 96.5 percent and 100 percent, respectively for serum samples collected more than 14 days after onset of the symptoms. Conclusions: The assays demonstrated high sensitivity and specificity, which allows us to have Cuban technology-based tools for serological, epidemiological surveillance, and other types of studies, including those related to vaccines on a platform with wide national distribution(AU)

SARS-CoV-2: theoretical analysis of the proposed algorithms to the enhancement and segmentation of high-resolution microscopy images-Part II.

Today is a reality that the novel coronavirus SARS-Cov-2 has become a global pandemic. For this reason, the study of real microscopic images of this coronavirus is of great importance, as it allows us to carry out a more precise research on it. However, as we pointed out in a former paper as reported by Roberto Rodríguez (SARS-CoV-2: Enhancement and Segmentation of High-Resolution Microscopy Images. Part I", Sent to Signal, Image and Video Processing Video Processing, Springer, New York, 2020), many times these microscopic images present some blurring problems, which are always susceptible to be improved. The aim of this work is to carry out a theoretical analysis of the proposed algorithms to enhancement and segmentation of these microscopic images, which is important for the design and development of future algorithms before new epidemics.

SARS-CoV-2: preliminary study of infected human nasopharyngeal tissue by high resolution microscopy.

BACKGROUND: The novel coronavirus SARS-CoV-2 is the etiological agent of COVID-19. This virus has become one of the most dangerous in recent times with a very high rate of transmission. At present, several publications show the typical crown-shape of the novel coronavirus grown in cell cultures. However, an integral ultramicroscopy study done directly from clinical specimens has not been published. METHODS: Nasopharyngeal swabs were collected from 12 Cuban individuals, six asymptomatic and RT-PCR negative (negative control) and six others from a COVID-19 symptomatic and RT-PCR positive for SARS CoV-2. Samples were treated with an aldehyde solution and processed by scanning electron microscopy (SEM), confocal microscopy (CM) and, atomic force microscopy. Improvement and segmentation of coronavirus images were performed by a novel mathematical image enhancement algorithm. RESULTS: The images of the negative control sample showed the characteristic healthy microvilli morphology at the apical region of the nasal epithelial cells. As expected, they do not display virus-like structures. The images of the positive sample showed characteristic coronavirus-like particles and evident destruction of microvilli. In some regions, virions budding through the cell membrane were observed. Microvilli destruction could explain the anosmia reported by some patients. Virus-particles emerging from the cell-surface with a variable size ranging from 80 to 400 nm were observed by SEM. Viral antigen was identified in the apical cells zone by CM. CONCLUSIONS: The integral microscopy study showed that SARS-CoV-2 has a similar image to SARS-CoV. The application of several high-resolution microscopy techniques to nasopharyngeal samples awaits future use.

Molecular Characterization of Coxsackievirus A24v from Feces and Conjunctiva Reveals Epidemiological Links.

Coxsackievirus A24 variant (CVA24v), the main causative agent of acute hemorrhagic conjunctivitis (AHC), can be isolated from both the eyes and lower alimentary tract. However, the molecular features of CVA24v in feces is not well-documented. In this study, we compared the VP1 and 3C sequences of CVA24v strains isolated from feces during AHC epidemics in Cuba in 1997, 2003, and 2008-2009 with those obtained from conjunctival swabs during the same epidemic period. The sequence analyses of the 3C and VP1 region of stool isolates from the three epidemics showed a high degree of nucleotide identity (ranging from 97.3-100%) to the corresponding conjunctival isolates. The phylogenetic analysis showed that fecal CVA24v isolates from the 1997 and 2003 Cuban outbreaks formed a clade with CVA24v strains isolated from conjunctival swabs in Cuba and other countries during the same period. There were three amino acid changes (3C region) and one amino acid change (VP1 region) in seven CVA24v strains isolated sequentially over 20 days from fecal samples of one patient, suggesting viral replication in the intestine. Despite these substitutions, the virus from the conjunctival swab and fecal samples were genetically very similar. Therefore, fecal samples should be considered as a reliable alternative sample type for the routine molecular diagnosis and molecular epidemiology of CVA24v, also during outbreaks of AHC.

SARS-CoV-2: enhancement and segmentation of high-resolution microscopy images-Part I.

Possibly, and due to poor eating habits and unhealthy lifestyle, many viruses are transmitted to human people. Such is the case, of the novel coronavirus SARS-Cov-2, which has expanded of exponential way, practically, to whole world population. For this reason, the enhancement of real microscopic images of this coronavirus is of great importance. Of this way, one can highlight the S-spikes and visualizing those areas that show a high density, which are related to active zones of viral germination and major spread of the virus. The SARS-Cov-2 images were captured from nasopharyngeal samples of Cuban symptomatic individuals (RT-PCR positives for SARS-CoV-2) and processed via scanning electron microscopy. However, many times these microscopic images present some blurring problems, and the S-spikes do not look well defined. Therefore, the aim of this work is to propose new computational methods to carry out enhancement and segmentation of SARS-Cov-2 high-resolution microscopic images. The proposed strategy obtained very satisfactory results, and we validated its performance, together with specialist physicians, on a set of 1005 images. Due to the importance of the obtained results, this first work will be addressed to the application of the proposed algorithm. A second paper will deeply analyze the theory related to these algorithms.

Association of Early Nasopharyngeal Immune Markers With COVID-19 Clinical Outcome: Predictive Value of CCL2/MCP-1.

Early recognition of severe forms of coronavirus disease 2019 (COVID-19) is essential for an opportune and effective intervention, reducing life-risking complications. An altered inflammatory immune response seems to be associated with COVID-19's pathogenesis and progression to severity. Here we demonstrate the utility of early nasopharyngeal swab samples for detection of the early expression of immune markers and the potential value of CCL2/MCP-1 in predicting disease outcome.

Molecular evolution of coxsackievirus A24v in Cuba over 23-years, 1986-2009.

Coxsackievirus A24 variant (CVA24v) is a major causative agent of acute hemorrhagic conjunctivitis outbreaks worldwide, yet the evolutionary and transmission dynamics of the virus remain unclear. To address this, we analyzed and compared the 3C and partial VP1 gene regions of CVA24v isolates obtained from five outbreaks in Cuba between 1986 and 2009 and strains isolated worldwide. Here we show that Cuban strains were homologous to those isolated in Africa, the Americas and Asia during the same time period. Two genotypes of CVA24v (GIII and GIV) were repeatedly introduced into Cuba and they arose about two years before the epidemic was detected. The two genotypes co-evolved with a population size that is stable over time. However, nucleotide substitution rates peaked during pandemics with 4.39 × 10-3 and 5.80 × 10-3 substitutions per site per year for the 3C and VP1 region, respectively. The phylogeographic analysis identified 25 and 19 viral transmission routes based on 3C and VP1 regions, respectively. Pandemic viruses usually originated in Asia, and both China and Brazil were the major hub for the global dispersal of the virus. Together, these data provide novel insight into the epidemiological dynamics of this virus and possibly other pandemic viruses.

Immunogenicity of Intramuscular Fractional Dose of Inactivated Poliovirus Vaccine.

BACKGROUNDS: Intradermal (id) fractional inactivated poliovirus vaccine ([fIPV] one fifth of normal IPV dose) is safe and immunogenic; however, id administration is perceived as difficult. We compared fIPV immunogenicity administered id or intramuscularly (im). METHODS: This noninferiority trial was conducted among polio vaccine-naive Cuban infants who received 2 IPV doses at 4 and 8 months of age. Infants were randomized into 4 arms: (A) fIPV, 0.1 mL im; (B) fIPV, 0.2 mL im; (C) fIPV, 0.1mL id; and (D) IPV, 0.5 mL im. Blood collected before and after vaccinations was tested for poliovirus-neutralizing antibodies. RESULTS: A total of 196 of 214 (91.6%) enrolled children completed study. Seroconversion after 2 IPV doses in each arm were as follows: (A) 97.3% (90.6-99.7), 98.7% (92.7-99.9), and 90.5% (81.5-96.1) for serotypes 1, 2, and 3, respectively; (B) 97.2% (90.3-99.7), 100%, 95.8% (88.3-99.1) for serotypes 1, 2, and 3, respectively; (C) 89.3% (71.8-97.7), 92.9% (76.5-99.1), 82.1% (63.1-93.9) for serotypes 1, 2, and 3, respectively; and (D) 100%, 100%, 100% for serotypes 1, 2, and 3, respectively. Seroconversion with fIPV im was noninferior to fIPV id for all serotypes. CONCLUSIONS: We demonstrated noninferiority of fIPV im compared with id when administered at 4 and 8 months of age. Further investigations in an earlier infant schedule should be pursued to explore fIPV im as option for dose-sparing strategy in countries reluctant to use fIPV id due to programmatic difficulties of id administration.

Does Simultaneous Administration of Bivalent (Types 1 and 3) Oral Poliovirus Vaccine and Inactivated Poliovirus Vaccine Induce Mucosal Cross-immunity to Poliovirus Type 2?

Background: Inactivated poliovirus vaccine (IPV) alone does not induce mucosal immunity. However, it was hypothesized that administration of IPV together with bivalent (types 1+3) oral poliovirus vaccine (bOPV) may stimulate mucosal cross-immunity to poliovirus type 2 (PV2). Methods: Cuban infants were randomized to receive either one dose of IPV (Arm A); one dose of IPV with bOPV (Arm B) at about 6 months of age or no vaccine (Arm C). Subjects were challenged with one dose of trivalent OPV (tOPV); they were about 7 months old in arms A and B, and about 3 months old in arm C at a time of the tOPV challenge. Sera were collected before vaccination and 30 days after tOPV challenge and tested for presence of poliovirus neutralizing antibodies; stool samples were collected at days 0, 7, 14, 21 and 49 post-challenge and tested for presence of poliovirus. Results: We enrolled 333 children. Excretion of PV2 following tOPV challenge was highest on day 7 (75 [CI 95% = 65-82%], 68 [CI 95% = 58-75%] and 73 [CI 95% = 63-80%] for study arms A, B, and C respectively); excretion decreased with every subsequent stool sampling; no significant differences either in proportion of PV2 excretion or in its duration were observed between study arms. Conclusions: There was no reduction in excretion of PV2 after tOPV challenge in children who had received IPV with bOPV when compared to those who had received IPV alone or no vaccine. Polio eradication program cannot assume any PV2 mucosal response with the current polio immunization schedule. Clinical Trials Registration: The trial was registered with the Australian New Zealand Clinical Trials Registry and allocated trial number ACTRN12616000169448.

Cuba's Scientific Contributions to Global Polio Eradication.

Cuba eliminated polio in 1962 and was among the first countries to do so. Since then, only 20 cases of vaccine-derived paralytic poliomyelitis have been reported. Because Cuba used oral poliovirus vaccine exclusively in two mass campaigns usually in February and April each year, Sabin viruses were detected only within approximately 6-8 weeks after each annual campaign. This made Cuba a very attractive site to study the epidemiology of poliomyelitis in a tropical country without risk of secondary transmission of Sabin viruses for a large part of each year, an advantage over countries that used oral poliovirus vaccine continuously throughout the year in routine immunization programs. This report summarizes the unique scientific collaboration between Cuba's Ministry of Public Health and WHO, with participation by US scientists, in the global effort to eradicate polio. KEYWORDS Poliomyelitis, disease eradication, disease elimination, oral poliovirus vaccine, Sabin vaccine, inactivated poliovirus vaccine, Salk vaccine, Cuba, WHO.

The Cuba-United States Thaw: Building Bridges Through Science and Global Health.

AbstractBeginning in 2014, there has been significant progress in normalization of relations between Cuba and the United States. Herein, we discuss the history and recent progress in scientific collaboration between the two countries as well as the continued challenges. Science and global health diplomacy can be key tools in reestablishing a trusting and productive relationship of mutual and global benefit, bringing about better and healthier lives for people in both Cuba and the United States.

Boosting Immune Responses Following Fractional-Dose Inactivated Poliovirus Vaccine: A Randomized, Controlled Trial.

BACKGROUND: Fractional-dose administration of inactivated poliovirus vaccine (fIPV) could increase IPV affordability and stretch limited supplies. We assessed immune responses following fIPV administered intradermally, compared with full-dose IPV administered intramuscularly, among adults with a history of oral poliovirus vaccine (OPV) receipt. METHODS: We conducted a randomized, controlled noninferiority trial in Cuba. fIPV or IPV were administered on days 0 and 28; serum was collected on days 0, 7, 28, and 56 for analysis by a neutralization assay. The primary end point was seroconversion or a ≥4-fold rise in antibody titer. The noninferiority limit was 10%. The secondary end point was safety, assessed by the number and intensity of adverse reactions. RESULTS: A total of 503 of 534 enrolled participants (94.2%) completed all study requirements. Twenty-eight days after the first dose, 94.8%, 98.0%, and 98.0% of fIPV recipients had an immune response to poliovirus types 1, 2, and 3, respectively, compared with 98.1% (P = .06), 98.0% (P = 1.00), and 99.2% (P = .45) in the IPV arm. Noninferiority was achieved on days 7, 28, and 56 for all serotypes. No serious adverse events were reported. CONCLUSION: fIPV induced similar boosting immune responses, compared with full-dose IPV. This suggests that fIPV would be an effective strategy to boost population immunity in an outbreak situation. CLINICAL TRIALS REGISTRATION: ACTRN12615000305527.

Needle-free jet injector intradermal delivery of fractional dose inactivated poliovirus vaccine: Association between injection quality and immunogenicity.

INTRODUCTION: The World Health Organization recommends that as part of the polio end-game strategy a dose of inactivated poliovirus vaccine (IPV) be introduced by the end of 2015 in all countries currently using only oral poliovirus vaccine (OPV). Administration of fractional dose (1/5 of full dose) IPV (fIPV) by intradermal (ID) injection may reduce costs, but its conventional administration is with Bacillus Calmette-Guerin (BCG) needle and syringe (NS), which is time consuming and technically challenging. We compared injection quality achieved with BCG NS and three needle-free jet injectors and assessed ergonomic features of the injectors. METHODS: Children between 12 and 20 months of age who had previously received OPV were enrolled in the Camaguey, Cuba study. Subjects received a single fIPV dose administered intradermally with BCG NS or one of three needle-free injector devices: Bioject Biojector 2000® (B2000), Bioject ID Pen® (ID Pen), or PharmaJet Tropis® (Tropis). We measured bleb diameter and vaccine loss as indicators of ID injection quality, with desirable injection quality defined as bleb diameter ≥5mm and vaccine loss <10%. We surveyed vaccinators to evaluate ergonomic features of the injectors. We further assessed the injection quality indicators as predictors of immune response, measured by increase in poliovirus neutralizing antibodies in blood between day 0 (pre-IPV) and 21 (post-vaccination). RESULTS: Delivery by BCG NS and Tropis resulted in the highest proportion of subjects with desirable injection quality; health workers ranked Biojector2000 and Tropis highest for ergonomic features. We observed that vaccine loss and desirable injection quality were associated with an immune response for poliovirus type 2 (P=0.02, P=0.01, respectively). CONCLUSIONS: Our study demonstrated the feasibility of fIPV delivery using needle-free injector devices with high acceptability among health workers. We did not observe the indicators of injection quality to be uniformly associated with immune response.

Decay of Sabin inactivated poliovirus vaccine (IPV)-boosted poliovirus antibodies.

INTRODUCTION: We conducted a follow-on study to a phase I randomized, controlled trial conducted in Cuba, 2012, to assess the persistence of poliovirus antibodies at 21-22 months following booster dose of Sabin-IPV compared to Salk-IPV in adults who had received multiple doses of oral poliovirus vaccine (OPV) during childhood. METHODS: In 2012, 60 healthy adult males aged 19-23 were randomized to receive one booster dose, of either Sabin-inactivated poliovirus vaccine (Sabin-IPV), adjuvanted Sabin-IPV (aSabin-IPV), or conventional Salk-IPV. In the original study, blood was collected at days 0 (before) and 28 (after vaccination), respectively. In this study, an additional blood sample was collected 21-22 months after vaccination, and tested for neutralizing antibodies to Sabin poliovirus types 1, 2 and 3. RESULTS: We collected sera from 59/60 (98.3%) subjects; 59/59 (100%) remained seropositive to all poliovirus types, 21-22 months after vaccination. The decay curves were very similar among the study groups. Between day 28 and 21-22 months, there was a reduction of ⩾87.4% in median antibody levels for all poliovirus types in all study groups, with no significant differences between the study groups. CONCLUSION: The decay of poliovirus antibodies over a 21-22-month period was similar regardless of the type of booster vaccine used, suggesting the scientific data of Salk IPV long-term persistence and decay may be broadly applicable to Sabin IPV.

Immune responses after fractional doses of inactivated poliovirus vaccine using newly developed intradermal jet injectors: a randomized controlled trial in Cuba.

INTRODUCTION: The World Health Organization recommends that, as part of the new polio endgame, a dose of inactivated poliovirus vaccine (IPV) be introduced by the end of 2015 in all countries using only oral poliovirus vaccine (OPV). Administration of fractional dose (1/5th of full dose) IPV (fIPV) intradermally may reduce costs, but its administration is cumbersome with BCG needle and syringe. We evaluated performance of two newly developed intradermal-only jet injectors and compared the immune response induced by fIPV with that induced by full-dose IPV. METHODS: Children between 12 and 20 months of age, who had previously received two doses of OPV, were enrolled in Camaguey, Cuba. Subjects received a single dose of IPV (either full-dose IPV intramuscularly with needle and syringe or fIPV intradermally administered with one of two new injectors or with BCG needle or a conventional needle-free injector). Serum was tested for presence of poliovirus neutralizing antibodies on day 0 (pre-IPV) and on days 3, 7 and 21 (post-vaccination). RESULTS: Complete data were available from 74.2% (728/981) subjects. Baseline median antibody titers were 713, 284, and 113 for poliovirus types 1, 2, and 3, respectively. Seroprevalence at study end were similar across the intervention groups (≥ 94.8%). The immune response induced with one new injector was similar to BCG needle and to the conventional injector; and superior to the other new injector. fIPV induced significantly lower boosting response compared to full-dose IPV. No safety concerns were identified. INTERPRETATION: One of the two new injectors demonstrated its ability to streamline intradermal fIPV administration, however, further investigations are needed to assess the potential contribution of fIPV in the polio endgame plan.

Reactogenicity and immunogenicity of inactivated poliovirus vaccine produced from Sabin strains: a phase I Trial in healthy adults in Cuba.

BACKGROUND: To ensure that developing countries have the option to produce inactivated poliovirus vaccine (IPV), the Global Polio Eradication Initiative has promoted the development of an IPV using Sabin poliovirus strains (Sabin IPV). This trial assessed the reactogenicity and immunogenicity of Sabin IPV and adjuvanted Sabin IPV in healthy adults in Cuba. METHODS: This is a randomized, controlled phase I trial, enrolling 60 healthy (previously vaccinated) male human volunteers, aged 19-23 years to receive one dose of either Sabin IPV (20:32:64 DU/dose), adjuvanted Sabin IPV (10:16:32 DU/dose), or conventional Salk IPV (40:8:32 DU/dose). The primary endpoint for reactogenicity relied on monitoring of adverse events. The secondary endpoint measured boosting immune responses (i.e. seroconversion or 4-fold rise) of poliovirus antibody, assessed by neutralization assays. RESULTS: Sixty subjects fulfilled the study requirements. No serious adverse events reported were attributed to trial interventions during the 6-month follow-up period. Twenty-eight days after vaccination, boosting immune responses against poliovirus types 1-3 were between 90% and 100% in all vaccination groups. There was a more than 6-fold increase in median antibody titers between pre- and post-vaccination titers in all vaccination groups. DISCUSSION: Both Sabin IPV and adjuvanted Sabin IPV were well tolerated and immunogenic against all poliovirus serotypes. This result suggests that the aluminum adjuvant may allow a 50% (or higher) dose reduction.

Coxsackievirus A6 and enterovirus 71 causing hand, foot and mouth disease in Cuba, 2011-2013.

Hand, foot and mouth disease (HFMD) is usually caused by coxsackievirus A16 or enterovirus 71 (EV71). Between 2011 and 2013, HFMD cases were reported from different Cuban provinces. A total of 42 clinical specimens were obtained from 23 patients. Detection, identification and phylogenetic analysis of enterovirus-associated HFMD were carried out by virus isolation, specific enterovirus PCR and partial VP1 sequences. HEV was detected in 11 HFMD cases. Emerging genetic variants of coxsackievirus A6 and EV71 were identified as the causative agents of the Cuban HFMD cases.

Priming after a fractional dose of inactivated poliovirus vaccine.

BACKGROUND: To reduce the costs of maintaining a poliovirus immunization base in low-income areas, we assessed the extent of priming immune responses after the administration of inactivated poliovirus vaccine (IPV). METHODS: We compared the immunogenicity and reactogenicity of a fractional dose of IPV (one fifth of a full dose) administered intradermally with a full dose administered intramuscularly in Cuban infants at the ages of 4 and 8 months. Blood was collected from infants at the ages of 4 months, 8 months, 8 months 7 days, and 8 months 30 days to assess single-dose seroconversion, single-dose priming of immune responses, and two-dose seroconversion. Specimens were tested with a neutralization assay. RESULTS: A total of 320 infants underwent randomization, and 310 infants (96.9%) fulfilled the study requirements. In the group receiving the first fractional dose of IPV, seroconversion to poliovirus types 1, 2, and 3 occurred in 16.6%, 47.1%, and 14.7% of participants, respectively, as compared with 46.6%, 62.8%, and 32.0% in the group receiving the first full dose of IPV (P<0.008 for all comparisons). A priming immune response to poliovirus types 1, 2, and 3 occurred in 90.8%, 94.0%, and 89.6% of participants, respectively, in the group receiving the fractional dose as compared with 97.6%, 98.3%, and 98.1% in the group receiving the full dose (P=0.01 for the comparison with type 3). After the administration of the second dose of IPV in the group receiving fractional doses, cumulative two-dose seroconversion to poliovirus types 1, 2, and 3 occurred in 93.6%, 98.1%, and 93.0% of participants, respectively, as compared with 100.0%, 100.0%, and 99.4% in the group receiving the full dose (P<0.006 for the comparisons of types 1 and 3). The group receiving intradermal injections had the greatest number of adverse events, most of which were minor in intensity and none of which had serious consequences. CONCLUSIONS: This evaluation shows that vaccinating infants with a single fractional dose of IPV can induce priming and seroconversion in more than 90% of immunized infants. (Funded by the World Health Organization and the Pan American Health Organization; Australian New Zealand Clinical Trials Registry number, ACTRN12610001046099.).

Type 1 diabetes associated and tissue transglutaminase autoantibodies in patients without type 1 diabetes and coeliac disease with confirmed viral infections.

Coeliac disease and type 1 diabetes are autoimmune diseases that may share the same initiating environmental factors. In this study, the occurrence of type 1 diabetes associated autoantibodies (GADA and IA-2A) and tissue transglutaminase autoantibodies (TGA) was determined in patients with confirmed viral infections and no signs of type 1 diabetes or coeliac disease. Serum samples from 82 Cuban patients tested positive for PCR and IgG specific to enterovirus (HEV, serotype echovirus 16, 20 samples), Epstein-Barr virus (EBV, 20 samples), cytomegalovirus (CMV, 21 samples), and hepatitis C virus (HCV, 21 samples); and sera from 164 controls negative serologically to EBV, CMV, HCV, and echovirus 16 were enrolled in the study. All subjects were screened for GADA, IA-2A, and TGA. The prevalence of TGA in patients infected with HEV, EBV, CMV, or HCV was 55% (11/20), 25% (5/20), 9.5% (2/21), and 9.5% (2/21), respectively. GADA and IA-2A were found in 15% (3/20) and 25% (5/20) of patients infected with HEV. None of the patients infected by EBV, CMV, and HCV had GADA or IA-2A. All children infected with HEV who were positive for type 1 diabetes-associated autoantibodies were also TGA-positive. None of the sera from uninfected subjects were positive for GADA, IA-2A or TGA. In conclusion, TGA can develop during infection with HEV, EBV, CMV, or HCV, while the emergence of islet cell related autoantibodies is restricted to HEV infections. The findings suggest that HEV may be a shared environmental factor for the development of islet and gut-related autoimmunity.