Seropositivity Rate Research Articles

Diphtheria and Tetanus Immunity Status among Greek Adults: Results from a Nationwide Seroprevalence Study.

Diphtheria and tetanus could lead to serious morbidity. We aimed to evaluate immunity levels by measuring specific IgG antibodies for diphtheria and tetanus in serum samples from a nationally expanded sample of the Greek population. A geographically stratified sampling approach based on regional units (NUTS level 2) was applied by considering variables such as age group (30-80+) and sex. In total, 1201 persons (47.7% males and 52.3% females) participated in the survey. Bivariate analysis revealed a negative relationship between diphtheria and tetanus median antibody titers and age. The overall seropositivity rate for diphtheria IgG antibodies (≥0.10 IU/mL) was estimated at 31.5%. Regarding tetanus, the total seropositivity rate was estimated at 59.5% (tetanus IgG antibodies ≥0.10 IU/mL). Logistic regression analysis indicated that age groups <40 years and 40-59 years were independently associated with tetanus seropositivity. Logistic regression also revealed that male sex and being aged 60-69 years were independent risk factors for diphtheria-related seropositivity. Lastly, being resident of some regions was an independent risk factor for both diphtheria- and tetanus-related seropositivity. The present study shows that Greek adults are still not completely immune to diphtheria and tetanus. It is likely possible to achieve optimal immunization coverage by implementing serviceable public health initiatives after comprehending real community needs.

Optimization of Mother-to-Child Hepatitis B Virus Prevention Program: Integration of Maternal Screening and Infant Post-Vaccination Serologic Testing.

Evaluation of the impact of a hepatitis B virus (HBV) prevention program that incorporates maternal antiviral prophylaxis on mother-to-child transmission (MTCT) is limited using real-world data. We analyzed data on maternal HBV screening, neonatal immunization, and post-vaccination serologic testing (PVST) for hepatitis B surface antigen (HBsAg) among at-risk infants born to HBV carrier mothers from the National Immunization Information System during 2008-2022. Through linkage with the National Health Insurance Database, information on maternal antiviral therapy was obtained. Multivariate logistic regression was performed to explore MTCT risk in relation to infant-mother characteristics and prevention strategies. In total, 2 460 218 deliveries with maternal HBV status were screened. Between 2008 and 2022, the annual HBsAg and hepatitis B e antigen (HBeAg) seropositivity rates among native pregnant women decreased from 12.2% to 2.6% and from 2.7% to 0.4%, respectively (P for both trends < .0001). Among the 22 859 at-risk infants who underwent PVST, the MTCT rates differed between infants born to HBsAg-positive/HBeAg-negative and HBeAg-positive mothers (0.75% and 6.33%, respectively; P < .001). MTCT risk increased with maternal HBeAg positivity (odds ratio [OR], 9.29; 95% confidence interval [CI], 6.79-12.73) and decreased with maternal antiviral prophylaxis (OR, 0.28; 95% CI, .16-.49). For infants with maternal HBeAg positivity, MTCT risk was associated with mothers born in the immunization era (OR, 1.40; 95% CI, 1.17-1.67). MTCT was related to maternal HBeAg positivity and effectively prevented by maternal prophylaxis in the immunized population. At-risk infants born to maternal vaccinated cohorts might possibly pose further risk.

Comprehensive landscape of neutralizing antibody and cell-mediated response elicited by the 1/5 fractional dose of 17DD-YF primary vaccination in adults

The present study aimed at evaluating the YF-specific neutralizing antibody profile besides a multiparametric analysis of phenotypic/functional features of cell-mediated response elicited by the 1/5 fractional dose of 17DD-YF vaccine, administered as a single subcutaneous injection. The immunological parameters of each volunteer was monitored at two time points, referred as: before (Day 0) [Non-Vaccinated, NV(D0)] and after vaccination (Day 30–45) [Primary Vaccinees, PV(D30–45)]. Data demonstrated high levels of neutralizing antibodies for PV(D30–45) leading to a seropositivity rate of 93%. A broad increase of systemic soluble mediators with a mixed profile was also observed for PV(D30–45), with IFN-γ and TNF-α presenting the highest baseline fold changes. Integrative network mapping of soluble mediators showed increased correlation numbers in PV(D30–45) as compared to NV(D0) (532vs398). Moreover, PV(D30–45) exhibited increased levels of Terminal Effector (CD45RA+CCR7−) CD4+ and CD8+ T-cells and Non-Classical memory B-cells (IgD+CD27+). Dimensionality reduction of Mass Cytometry data further support these findings. A polyfunctional cytokine profile (TNF-α/IFN-γ/IL-10/IL-17/IL-2) of T and B-cells was observed upon in vitro antigen recall. Mapping and kinetics timeline of soluble mediator signatures for PV(D30–45) further confirmed the polyfunctional profile upon long-term in vitro culture, mediated by increased levels of IFN-γ and TNF-α along with decreased production of IL-10. These findings suggest novel insights of correlates of protection elicited by the 1/5 fractional dose of 17DD-YF vaccine.

A Pilot Seroprevalence Study Suggests Silent Zika virus Transmission in Bhopal Region of Central India.

Several sporadic cases and outbreaks of Zika virus disease have been reported from different states of India. This paper explored the possibility of any ongoing transmission of Zika virus (ZIKV) in the Bhopal region of Central India, where the last outbreak of this disease was reported in 2018. We screened a group of 75 febrile patients who had already tested negative for the locally endemic causes of fever like dengue, chikungunya, enteric fever, malaria, and scrub typhus and two groups of asymptomatic healthy individuals represented by blood donors (n = 75) and antenatal mothers (n = 75). We tested blood samples of febrile patients for ZIKV RNA using real-time polymerase chain reaction (PCR), and for the healthy individuals, we determined anti-zika immunoglobulin G (IgG) antibodies using enzyme-linked immunosorbent assay. ZIKV RNA was not detected in any of the 75 samples tested by real-time PCR assay. Among the voluntary blood donors and antenatal mothers, a total of 10 (15.38%) and 5 (6.66%) individuals were found to be seropositive for anti-ZIKV IgG antibodies, respectively. The seropositive group was found to have higher age 33.06 (±10.83) years as compared to seronegative individuals 26.60 (±5.12) years (P = 0.037). This study, which is the first survey of seroprevalence of anti-Zika antibodies from India, reports an overall seropositivity rate of 10% for anti-Zika antibodies among the healthy population, suggesting an ongoing, low level, silent transmission of ZIKV in the local community.

Immunogenicity Assessment of the SARS-CoV-2 Protein Subunit Recombinant Vaccine (CoV2-IB 0322) in a Substudy of a Phase 3 Trial in Indonesia.

COVID-19 is one of the most devastating pandemics of the 21st century. Vaccination is one of the most effective prevention methods in combating COVID-19, and one type of vaccine being developed was the protein subunit recombinant vaccine. We evaluated the efficacy of the CoV2-IB 0322 vaccine in Depok, Indonesia. This study aimed to assess the humoral and cellular immune response of the CoV2-IB 0322 vaccine compared to an active control vaccine (COVOVAX™ Vaccine). A total of 120 subjects were enrolled and randomized into two groups, with 60 subjects in each group. Participants received either two doses of the CoV2-IB 0322 vaccine or two doses of the control vaccine with a 28-day interval between doses. Safety assessments were conducted through onsite monitoring and participant-reported adverse events. Immunogenicity was evaluated by measuring IgG anti-RBD SARS-CoV-2 and IgG-neutralizing antibodies. Cellular immunity was assessed by specific T-cell responses. Whole blood samples were collected at baseline, 14 days, 6 months, and 12 months after the second dose for cellular immunity evaluation. Both vaccines showed high seropositive rates, with neutralizing antibody and IgG titers peaking 14 days after the second dose and declining by 12 months. The seroconversion rate of anti-S IgG was 100% in both groups, but the rate of neutralizing antibody seroconversion was lower in the CoV2-IB 0322 vaccine group at 14 days after the second dose (p = 0.004). The CoV2-IB 0322 vaccine showed higher IgG GMT levels 6 and 12 months after the second dose (p < 0.001 and p = 0.01). T-cell responses, evaluated by IFN-γ, IL-2, and IL-4 production by CD4+ and CD8+ T-cells, showed similar results without significant differences between both groups, except for %IL-2/CD4+ cells 6 months after the second dose (p = 0.038). Both vaccines showed comparable B- and T-cell immunological response that diminish over time.

Incidence of canine viral diseases and prevalence of virus neutralization antibodies of canine distemper virus, adenovirus type 2, parvovirus, and parainfluenza virus type 5 in Korean dogs

Canine distemper virus (CDV), canine adenovirus type 2 (CAV-2), canine parvovirus (CPV), and canine parainfluenza virus 5 (CPIV-5) are the major viral pathogens in dogs. Despite the availability of vaccines for dogs against these four viral pathogens, investigations of antibodies against these pathogens have rarely been reported in South Korea. In this study, we investigated the recent incidence of viral diseases in dogs and conducted sero-surveillance for CDV, CAV-2, CPV, and CPIV-5 in Korean dogs. The most frequently diagnosed canine viral disease in Korean dog samples from 2000 to 2022 was CPV infection, which accounted for 48.7% (464/953) of the cases. A total of 400 dog serum samples collected between 2019 and 2022 were screened for the presence of virus-neutralizing antibodies against CDV, CAV-2, CPV, and CPIV-5. The overall seropositivity rates for CDV, CAV-2, CPV, and CPIV-5 were 83.8%, 77.8%, 99.3%, and 82.0%, respectively. The protection rate against CPV was the highest (98.3%) and that against CAV-2 was the lowest (44.8%) in dog sera. Male and female dogs showed no significant differences in seropositivity rates. CDV and CPIV-5 seropositivity increased with age in dogs, and the highest incidence and seropositivity rates of CPV indicated that Korean dogs have been continuously exposed to wild CPV, and that CPV is a pathogen that urgently requires attention among canine viral diseases.

Strongyloidiasis in Auckland: A ten-year retrospective study of diagnosis, treatment and outcomes of a predominantly Polynesian and Fijian migrant cohort.

Strongyloides stercoralis is not endemic in Aotearoa New Zealand (AoNZ). However, approximately one third of Auckland residents are born in endemic countries. This study aimed to describe the epidemiology and management of strongyloidiasis in Auckland, with a focus on migrants from Pacific Island Countries and Territories. This study retrospectively reviewed clinical, laboratory and pharmacy records data for all people diagnosed with strongyloidiasis in the Auckland region between July 2012 and June 2022. People with negative Strongyloides serology were included to estimate seropositivity rate by country of birth. Over ten years, 691 people were diagnosed with strongyloidiasis. Most diagnoses were made by serology alone (622, 90%). The median age was 63 years (range 15-92), 500 (72%) were male, and the majority were born in Polynesia (350, 51%), Fiji (130, 19%) or were of Pasifika ethnicity (an additional 7%). Twelve participants (1.7%) had severe strongyloidiasis at diagnosis. The total proportion treated with ivermectin was only 70% (484/691), with no differences between immunocompromised and immunocompetent participants, nor by ethnicity. The outcome of treatment (based on a combination of serology and/or eosinophilia and/or stool microscopy) could only be determined in 50% of the treated cohort. One participant failed treatment with ivermectin, experiencing recurrent strongyloidiasis, and another participant died in association with severe strongyloidiasis. The rate of 'positive' Strongyloides serology was highest among participants born in Samoa (48%), Fiji (39%), and Southeast Asian countries (34%). Strongyloidiasis was common and under-treated in Auckland during the study period. Clinicians should have a low threshold for considering strongyloidiasis in migrants from endemic countries, including Polynesia and Fiji.

Two-Center Comparison of Viral Hepatitis A, B, C Seroprevalence among the 18-25 Age Group

Objective: Viral hepatitis is inflammation of the liver due to a viral infection that affects millions of people worldwide, causing thousands of deaths due to acute-chronic infection, liver cancer and cirrhosis. This study is aimed to compare datas of the seroprevalence of markers for viral hepatitis A, B, C among 18-25 age group outpatient clinic patients and healthcare workers between the two University Hospitals from east and west zone of Turkey. Material and Methods: The data of a total of 562 patients and healthcare workers, aged between 18 and 25, who applied to the outpatient clinic at Sütçü İmam University Faculty of Medicine and Onsekiz Mart University Faculty of Medicine Hospital between 01.01.2022 and 01.07.2022, were retrospectively examined. The presence of serological markers against HAV, HBV, HCV and HIV was tested with the ELISA method. Results: Anti-HAV IgG positivity was 25.5% and 40.3% for Çanakkale and Kahramanmaraş, respectively. Anti-HAV seropositivity rate in Kahramanmaraş was statistically significantly higher than in Çanakkale (P&amp;lt;0.001). Anti-HBs positivity was found to be 74.5% and 75.4% for Çanakkale and Kahramanmaraş, which were similar to each other bulundu (P=0.458). HBsAg positivity was detected as 1.5% in Çanakkale and 0.8% in Kahramanmaraş. There was no significant difference between the two cities (P = 0.810). Anti-HCV was found to be positive in one (0.5%) patient in Çanakkale and in four (1.1%) patients in Kahramanmaraş. Anti-HCV positivity was higher in Kahramanmaraş and anti-HIV positivity was higher in Çanakkale (P=.03, P&amp;lt;0.001). It was detected that anti-HBs positivity (80.7%) was higher in HCWs and anti-HAV IgG positivity was higher in non-HCWs (38.4%) (P=.042, P=0.013). There was no significant difference between the 2 groups in terms of anti-HCV and anti-HIV positivity. Conclusion: Due to the low anti-HAV seropositivity rates in the 18-25 age group, this makes this group more risky in terms of HAV infection. Especially due to the anti-HAV positivity in Çanakkale is low compared to Kahramanmaraş, it is recommended to support vaccination in this region. Since health care workers are at risk of having and transmitting hepatitis, it was found to be appropriate getting prevention measures by screening against vaccine-preventable diseases.

A Retrospective Analysis of Systemic Bartonella henselae Infection in Children.

Systemic Bartonella henselae infection, also known as cat-scratch disease (CSD), presents a diagnostic challenge due to the variability of clinical manifestations and the potential for serological cross-reactivity with other organisms. This study aimed to retrospectively analyze the epidemiological, clinical, laboratory, and imaging characteristics of pediatric patients diagnosed with systemic B. henselae infection, to improve understanding and facilitate timely diagnosis and treatment. We conducted a 10-year retrospective study at the "Louis Turcanu" Children's Emergency Hospital and private clinics in Timisoara, Romania, reviewing records for confirmed cases of B. henselae infection from January 2014 to January 2024. The study adhered to the Declaration of Helsinki and received approval from the Institutional Review Board. Diagnostic criteria included contact with animals, prolonged fever, hematological and/or hepatosplenic manifestations, and positive serological tests for B. henselae. Nineteen pediatric patients were identified with a median age of 8.1 years. The majority were exposed to felines (94.7%), reflecting the disease's epidemiological profile. Clinical findings highlighted fever (47.4%), lymphadenopathy (78.9%), and less frequently, abdominal pain and headache (both 10.5%). Laboratory analyses revealed a mean hemoglobin of 12.6 mg/dL, WBC count of 13.1 × 103 cells/microliter, and platelet count of 340.6 × 103 per microliter. Significant findings included elevation in ESR and CRP in 47.4% and 21.1% of patients, respectively, and high seropositivity rates for B. henselae IgM (63.2%) and IgG (94.7%). Imaging studies demonstrated widespread lymphadenopathy and occasional splenomegaly and hepatic microabscesses. All patients received antibiotic therapy, with azithromycin being the most commonly used (94.7%). Co-infections with Epstein-Barr Virus, Cytomegalovirus, and Toxoplasma gondii were documented, indicating the complex infectious status of the patients. Systemic B. henselae infection in children predominantly manifests with fever and lymphadenopathy, with a significant history of exposure to felines. Laboratory and imaging findings support the diagnosis, which is further complicated by potential co-infections. Effective antibiotic therapy, primarily with azithromycin, underscores the need for comprehensive diagnostic and treatment strategies. This study emphasizes the importance of considering systemic B. henselae infection in pediatric patients with prolonged fever and contact with cats, to ensure timely and appropriate treatment.

Immunogenicity and Safety of Half-Dose Heterologous mRNA-1273 Booster Vaccination for Adults Primed with the CoronaVac® and ChAdOx1-S Vaccines for SARS-CoV-2.

Coronavirus disease 2019 (COVID-19) has been extensively researched, particularly with regard to COVID-19 vaccines. However, issues with logistics and availability might cause delays in vaccination programs. Thus, the efficacy and safety of half-dose heterologous mRNA should be explored. This was an open-label observational study to evaluate the immunogenicity and safety of half-dose mRNA-1273 as a booster vaccine among adults aged >18 years who underwent a complete primary SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) vaccination regimen with CoronaVac® and ChAdOx1-S. Adverse events (AEs), seropositivity rate, seroconversion, geometric mean titer (GMT) of SARS-CoV-2 antibodies, neutralizing antibodies, and T cells (CD4+ and CD8+) specific for SARS-CoV-2 were analyzed. Two hundred subjects were included in the final analysis, with 100 subjects in each priming vaccine group. Most of the AEs were mild, with systemic manifestations occurring between 1 and 7 days following vaccination. A significant difference was observed in the GMT and seropositivity rate following booster dose administration between the two groups. CD8+/CD3+, IFN (interferon)-producing CD8+, and TNF (tumor necrosis factor)-producing CD8+ cells showed significant increases in both groups. The administration of the half-dose mRNA-1273 booster is safe and effective in increasing protection against SARS-CoV-2 infection.

The seroepidemiology of immunoglobulin G antibodies against pertussis toxin and filamentous hemagglutinin in the east of China during the COVID-19 pandemic

ABSTRACT This study employed sero-epidemiological methods to estimate the incidence of pertussis within a healthy population located in eastern China. The aim was to gain deeper insights into the epidemiological characteristics and burden of pertussis within the country. Blood samples were collected from healthy individuals in Jiangsu Province between June 2019 and December 2022. The levels of IgG antibodies against pertussis toxin (anti-PT) and filamentous hemagglutinin (anti-FHA) in the serum were quantitatively measured using enzyme-linked immunosorbent assay (ELISA). Additionally, pertussis case data reported in Jiangsu Province were collected from the China Information System for Disease Control and Prevention and compared with the results of this study. In 2022, the reported incidence of pertussis stood at 1.0 per 100,000 individuals, marking the highest rate observed in the past two decades. Among 1,909 patients examined, the geometric mean concentration (GMC) of anti-PT IgG antibody was 20.2 (18.5–21.9) IU/ml, while that of anti-FHA IgG antibody was 27.0 (25.4–28.7) IU/ml. The IgG-PT and IgG-FHA seropositivity rate (>20.0 IU/ml) was highest in the 1 ~ 2 y old group and decreased rapidly to the lowest in the 3 ~ 4 y old group and then increased gradually with age. The estimated rate of pertussis infection based on seroprevalence was approximately 25,625‐fold higher than the reported notification rate in the ≥15 year age group. Our findings highlight decreased immunity post-vaccination, stressing the importance of additional booster shots for adolescents and adults to maintain immunity and reduce severe illness. Additionally, they offer vital guidance for policymakers to enhance immunization strategies.

Serostatus of Coxsackie B in a sample of women with miscarriage in Baghdad, Iraq.

The antibody that crosses transplacentally from mother to fetus is very important origin of protective passive immunity against infection neonatal with enterovirus. Important varieties of coxsackievirus B3 (CVB3) are responsible for infections in newborns. The purpose from this study is to investigate in the prevalence of Coxsackie B virus in a sample of Iraqi women with miscarriage and potential role of miscarriage risk. Between November 2022 and June 2023, we included 91parturient women (gestational age: 4-20weeks) who were between the ages of 15 and 40. Every participant completed a questionnaire, and blood was drawn to assess maternal antibodies against CVB3. The blood seropositive rates were 46 out 91(50.54%), 2 out 46 were IgM positive (4.34%), (8-12weeks) 23 from 46 (50%) (p-value 0.0294) gestational age more frequent among aborted women that positive for anti-coxsackie B antibody, The 25-35age group was significantly overrepresented (51/91, 56%) compared to other age groups. This investigation posits Coxsackie B virus (CBV) as a possible etiology for miscarriage in the Iraqi female population. Further studies employing larger cohorts and robust methodologies, beyond the current detection technique, are warranted to corroborate these observations and elucidate the potential mechanisms by which CBV might induce miscarriage.

Effectiveness and safety of immune response to SARS‑CoV‑2 vaccine in patients with chronic kidney disease and dialysis: A systematic review and meta‑analysis.

The coronavirus disease 2019 (COVID-19) vaccination is the most effective way to prevent COVID-19. However, for chronic kidney disease patients on long-term dialysis, there is a lack of evidence regarding the efficacy and safety of the immune response to the vaccine. The present meta-analysis explores the efficacy and safety of COVID-19 vaccine in the immune response of patients with chronic kidney disease (CKD) undergoing dialysis. PubMed, Web of Science, Science Direct, and Cochrane Library databases were systematically searched from January 1, 2020, to December 31, 2022. Data analysis was performed using REVMAN 5.1s and Stata14 software. Baseline data and endpoint events were extracted, mainly including age, sex, dialysis vintage, body mass index (BMI), vaccine type and dose, history of COVID-19 infection, seropositivity rate, antibody titer, pain at injection site, headache and other safety events. The meta-analysis included 33 trials involving 81,348 patients. The immune efficacy of patients with CKD and dialysis was 80% (95 CI, 73-87%). The seropositivity rate of individuals without COVID-19 infection was 76.48% (3,824/5,000), while the seropositivity rate of individuals with COVID-19 infection was 80.82% (1,858/2,299). The standard mean difference of antibody titers in CKD and dialysis patients with or without COVID-19 infection was 27.73 (95% CI, -19.58-75.04). A total of nine studies reported the most common adverse events: Pain at the injection site, accounting for 18% (95 CI, 6-29%), followed by fatigue and headache, accounting for 8 (95 CI, 4-13%) and 6% (95 CI, 2-9%), respectively. COVID-19 vaccine benefitted patients with CKD undergoing dialysis with seropositivity rate ≥80%. Adverse events such as fatigue, headache, and pain at the injection site may occur after COVID-19 vaccination but the incidence is low.

Seroprevalence of Canine Toxocariasis in Three Rural Areas of Fars Province, Southern Iran.

Toxocara canis is one of the most important causes of animal toxocariasis with global distribution. We aimed to find out the seroprevalence of toxocariasis in dogs in a rural area in Fars Province, south of Iran. Dogs blood samples were collected from 60 dogs in three rural areas in the Sar Mashhad region, Fars Province. Dog sera were evaluated for anti-Toxocara antibodies by an indirect ELISA method. The association between the seropositivity and age, gender, and the sampling location were statistically evaluated. Serological assay detected anti-Toxocara antibodies in sera of 32 out of 60 dogs, corresponding to a seroprevalence of 53.3%. The rate of seropositivity was higher in the male dogs. The rate of seropositivity was higher in old dogs. This rate increased with increasing age, however, the association between age and Toxocara seropositivity was not statistically significant. The high prevalence of Toxocara infection in dogs in the current study area confirms that infected dogs are an important source of Toxocara infection for their owners and people who are in close contact with these animals, especially children.

Influenza D virus in cattle (review)

The influenza D virus was first detected and identified in 2011. The overall amino acid sequence of influenza D virus shares approximately 50% identity with that of influenza C virus, suggesting that both viruses had a common ancestor. Cattle is considered to be the primary natural reservoir for influenza D virus. The involvement of this virus into the bovine respiratory disease complex has been confirmed. The virus causes mild to moderate disease in calves and replicates in both the upper and lower respiratory tracts, promoting bronchopneumonia. The influenza D virus can be transmitted by contact or aerosol over short distances, has a high transmission rate and can potentiate the effects of other respiratory pathogens. There are currently no vaccines or specific treatment for influenza D virus. This virus can replicate and be transmitted by direct contact in ferrets and guinea pigs, which are surrogate models of human influenza infection, as well as in well-differentiated human airway epithelial cells (hAECs). Currently five distinctive lineages of influenza D virus have been identified, co-circulating in worldwide bovine and pig populations that may facilitate genetic re-assortment between different viral strains. The virus has a zoonotic potential, and if its pathogenicity for humans changes, its importance for public health will be great. Very high seropositivity rates among persons working with cattle in the USA and Italy have been reported. There is no data in the available literature on the circulation of the influenza D virus in the Russian Federation. Research is needed to study this new virus, as well as monitoring of the virus spread and circulation in our country to understand its role in bovine respiratory disease complex and its zoonotic potential.

Scrub typhus among patients with acute febrile illness in a tertiary health care centre

Scrub typhus, caused by Orientia tsutsugamushi and transmitted by bite of larval trombiculid mite of the Leptotrombidium genus and is a vector borne zoonotic disease. It has been predominantly reported from Southeast Asia, the Asian Pacific Rim, and Australia. The incidence of this disease is increased in India. These patients show an acute undifferentiated febrile illness and laboratory confirmation is essential. Delay in diagnosis may be fatal. : To assess the Scrub typhus burden among acute febrile illness patients. This Cross-sectional study, conducted in Dept. of Microbiology, Basaveshwara Medical College &amp; Hospital, Chitradurga, Karnataka, India. Study duration was from August 2020 to January 2021. In this study, a total of 100 febrile illness patients were involved. Among them, 66 were males and 34 females. Under aseptic conditions, venous blood samples were collected from all subjects. Serum was separated by centrifugation, aliquoted, and stored at −20°C for further testing. The serum sample was tested for scrub typhus IgM ELISA using the INBIOS kit. Samples were also checked for dengue fever, typhoid fever, leptospirosis, and malaria. The serum samples that tested positive for any other infectious disease mentioned above (with or without detectable rickettsial antibodies) were excluded from the study. Data was represented in numbers and percentages. : In this study, out of 100 samples 30 were seropositive. Of the 30 seropositive scrub typhus cases, women were 11 (37%) and men were 19 (63%), suggesting that seropositivity was more in men than women. Among the seropositive cases, maximum number of the cases were in 16-30 years (33%) of age, followed by 31–45 years (23%). In this study, more number of positive cases 17 (56.6%) were found during the post-monsoon season i.e., October and November 2020. Fever, the most common symptom (100%). Headache, reported in (70 %) of cases, myalgia (40%), abdominal pain (37%), cough (23%), vomiting (20%), lymphadenopathy (17%), rashes (13%), hepato-spleenomegaly (10%), eschar (3%). The study results may conclude that Scrub typhus seropositivity rate was higher in males than females and also to be included in differential diagnosis of fever of unknown origin.

Comparison of homologous and heterologous inactivated and mRNA vaccination programme against SARS-CoV-2 in dialysis patients.

To evaluate the vaccine response and the effect of the booster dose on COVID-19 positivity in haemodialysis (HD) and peritoneal dialysis (PD) patients who received and did not receive BNT162b2 as a booster dose after two doses of CoronaVac. The study included 80 PD and 163 HD patients, who had been administered two doses of the CoronaVac. Antibody levels were measured on Days 42 and 90 after the first dose. Measurements were repeated on Day 181 after the first dose in the patients that received two vaccine doses and on Day 28 after the third dose in those that also received the booster dose. Antibody levels below 50 AU/mL were considered negative. The seropositivity rate was similar in the HD and PD group on Days 42 and 90 (p = 0.212 and 0.720). All patients were seropositive in the booster group. The antibody level was lower in the patients that received CoronaVac as the booster compared to those administered BNT162b2 in HD and PD groups (p < 0.001 and 0.002). COVID-19 positivity was detected in 11 patients (7 = had not received the booster dose, 4 = had received third dose of CoronaVac). The multivariate analysis revealed that as age increased, COVID-19 positivity also increased (OR: 1.080, 95% CI: 1.017 - 1.146, p = 0.012), while booster dose administration decreased this positivity (OR: 0.113, 95% CI: 0.028 - 0.457, p = 0.002). Our results may indicate the need for additional vaccination doses in patients with HD and PD. Our findings indicate a higher antibody response in dialysis patients with heterologous BNT162b2 as a booster dose after two doses of CoronaVac compared to homologous CoronaVac.

Clinical and seasonal pattern of dengue in a tertiary care hospital of South West India.

Dengue is an emerging global viral disease with an increase 30-fold in incidence in the past fifty years. In the past decade it was restricted to only few a states of South and Northern India but in the recent past it has affected almost all the states in India. The objective of this study was to assess the clinical profile, trends and outcome of dengue cases. This retrospective record based cross-sectional study was conducted in tertiary hospital, Mangaluru in Southern India. The study population included all dengue positive cases diagnosed either by IgM Capture ELISA or Dengue Non-structural Protein NS1 antigen over a period of five years. Information from pre-recorded case sheets were used for data collection. The data was analyzed using SPSS Version 20. Results from the analysis have been expressed in percentages, means and graphs. The study included 401 dengue cases. Most cases were in the age range of 20-40 years with a male to female ratio of 3:2. Overall seropositivity rate was 23.94% with High IgM prevalence. Monthly distribution showed a maximum cases were in the months of June and July and minimum were in January and February. Among the study participants, 91.5% of patients recovered completely and 1.7% of patients had died. 6.8% of patients were discharged against medical advice. Dengue continues to be major public health problem in this part of the globe affecting mainly the working age group. Low seropositivity with High IgM prevelance makes dengue an important differential for febrile illness of vague nature and invokes the need for robust public health response to curb the hyper-endemicity.

Comparison of Bordetella pertussis Antibody Levels in Pregnant Women and Umbilical Cord Blood: A Multicenter Study.

In countries where pertussis vaccination is not administered during pregnancy, the determination of pertussis antibody levels in pregnant women is very important in terms of knowing the current seroepidemiology and potential strategies for immunizations. We included 396 pregnant women who were admitted to 4 different obstetrics and gynecology clinics. Anti-Bordetella pertussis toxin (PT) IgG and anti-Bordetella pertussis filamentous hemagglutinin IgG levels in maternal and cord blood pairs were determined by the ELISA method. Venous blood serum anti-PT level was below 5 IU/mL in 58.8%, 5-40 IU/mL in 34.8%, 40-100 IU/mL in 5.1% and >100 IU/mL in 1.3% of pregnant women. Cord blood serum anti-PT level was below 5 IU/mL in 47.7%, 5-40 IU/mL in 44.5%, 40-100 IU/mL in 6.8% and >100 IU/mL in 1% of pregnant women. In our study, the anti-PT level was found below 40 IU/mL in 93.6% of pregnant women and 92.2% of cord blood. Our study found the anti-filamentous hemagglutinin level below 40 IU/mL in 81% of pregnant women and 66.2% of cord blood. Although it is known that pertussis causes serious morbidity and mortality in young infants all over the world and that the most effective and reliable way to prevent it is vaccination of pregnant women, it is a remarkable contradiction that pertussis vaccination rates and therefore seropositivity rates in pregnant women are very low.

Effect of Corticosteroids on Long-Term Humoral and Memory T-Cell Responses in Follow-Up Visit of Hospitalized Patients With COVID-19

Corticosteroids have beneficial effects in improving outcomes in hospitalized patients with severe COVID-19 by suppressing excessive immune responses. However, the effect of corticosteroids on the humoral and T-cell responses of survivors of COVID-19 1 year after infection remains uncertain, as it relates to the extent of immediate, antigen-specific defense provided by protective memory. What is the effect of corticosteroids on long-term humoral and T-cell immune responses? In this retrospective cohort study conducted at a single center, we analyzed data from a cohort who had survived COVID-19 to compare the 1-year seropositivity and titer changes in neutralizing antibodies (NAbs) and SARS-CoV-2-specific antibodies. Additionally, we evaluated the magnitude and rate of SARS-CoV-2-specific T-cell response in individuals who received corticosteroids during hospitalization and those who did not. Our findings indicated that corticosteroids do not statistically influence the kinetics or seropositive rate of NAbs against the Wuhan strain of SARS-CoV-2 from 6months to 1 year. However, subgroup analysis revealed a numerical increase of NAbs titers, from 20.0 to 28.2, in categories where long-term (> 15days) and high-dose (> 560mg) corticosteroids were administered. Similarly, corticosteroids showed no significant effect on nucleoprotein and receptor-binding domain IgG at 1 year, except for spike protein IgG (β, 0.08; 95%CI, 0.04-0.12), which demonstrated a delayed decline of titers. Regarding T-cell immunity, corticosteroids did not affect the rate or magnitude of T-cell responses significantly. However, functional assessment of memory Tcells revealed higher interferon-γ responses in CD4 (β, 0.61; 95%CI, 0.10-1.12) and CD8 (β, 0.63; 95%CI, 0.11-1.15) memory Tcells in the corticosteroids group at 1 year. Based on our findings, short-term and low-dose corticosteroid therapy during hospitalization does not appear to have a significant effect on long-term humoral kinetics or the magnitude and rate of memory T-cell responses to SARS-CoV-2 antigens. However, the potential harmful effects of long-term and high-dose corticosteroid use on memory immune responses require further investigation.