Significant Increase In Seroprevalence Research Articles

West Nile and Usutu virus seroprevalence in Hungary: A nationwide serosurvey among blood donors in 2019.

In Hungary, West Nile virus (WNV) has been responsible for 459 laboratory confirmed human cases between 2004 and 2019, while the first human Usutu virus (USUV) infection was confirmed only in 2018. A comprehensive serosurvey was conducted among blood donors to assess the WNV and USUV seroprevalence in 2019, one year after the largest European WNV epidemic. Altogether, 3005 plasma samples were collected and screened for WNV and USUV specific Immunoglobulin G (IgG) antibodies by Enzyme–Linked Immunosorbent Assay (ELISA). All reactive samples were further tested for tick-borne encephalitis virus IgG antibodies by ELISA. Indirect immunofluorescence test and microneutralization assay were used as confirmatory methods. Overall, the WNV seroprevalence was 4.32%, and in five blood donors USUV seropositivity was confirmed. The highest seroprevalence was measured in Central, Eastern and Southern Hungary, while the Western part of the country proved to be less affected. There was a statistically strong association between the WNV seroprevalence of 2019 and the cumulative incidence in the period of 2004 and 2019 calculated for every NUTS 3 region. The last WNV serological screening was performed in 2016 and the prevalence of anti-WNV IgG proved to be 2.19%. One year after the 2018 WNV outbreak, a significant increase in seroprevalence was observed in the Hungarian population and evidence for USUV seropositivity was also obtained. The spatial pattern of seroprevalence can support the identification of high-risk areas raising awareness of the need for increased surveillance, such as screening vector, equine, and avian populations. The communication with general practitioners and other professionals in primary health care services can support the early identification of acute human cases. Education and awareness-raising on the importance of protection against mosquito vectors amongst residents are also important parts of preventive measures.

Sero-prevalence and risk factors of Toxoplasma gondii infection in wild cervids in Denmark.

Toxoplasma gondii is a zoonotic protozoan parasite capable of infecting possibly all warm-blooded animals including humans, and is one of the most widespread zoonotic pathogens known. Free-ranging wildlife can be valuable sentinels for oocyst contaminated environments, as well as a potential source for human foodborne infection with T. gondii. Here we aimed to determine the sero-prevalence of T. gondii in Danish wild deer populations and examine risk factors associated with increased exposure to the parasite. Blood samples were collected from 428 cervids (87 fallow deer (Dama dama), 272 red deer (Cervus elaphus), 55 roe deer (Capreolus capreolus) and 14 sika deer (Cervus Nippon) from 23 hunting sites in Denmark. The animals were shot during the hunting season 2017/2018, and screened for antibodies against T. gondii using a commercial ELISA kit. One hundred and five (24.5%) cervids were sero-positive. Sero-prevalence was significantly different between species (p < 0.05), with odds of sero-positivity being 4.5 times higher in roe deer than fallow deer, and 3.0 times higher in red deer than in fallow deer. A significant increase in sero-prevalence with age was observed, driven by a significant increase in risk in adult red deer compared to calves (OR: 13.22; 95% CI: 5.96–33.7). The only other significant risk factor associated with wild cervid T. gondii sero-positivity was fencing, with the highest exposure associated with deer from non-fenced hunting areas (OR: 2.21; 95% CI: 1.05–4.99). This study documented a widespread exposure to T. gondii in Danish cervids. Therefore the meat of the wild deer, in particular from roe deer and red deer, should be considered a significant risk of T. gondii infections to humans, if not properly cooked. Further, molecular studies to confirm the presence of infective parasitic stages in the muscles of deer used for consumption is recommended.

SARS-CoV-2 Seroprevalence in Healthcare Workers before the Vaccination in Poland: Evolution from the First to the Second Pandemic Outbreak.

Healthcare workers (HCWs) are on the frontline, struggling with the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To describe recent or past infections, the serological assays enabled the assessment of the immune response developed in coronavirus disease (COVID-19) in the period when testing was hardly available. In this study, we investigated SARS-CoV-2 seroprevalence in HCWs in a Polish teaching hospital and the Regional Occupational Medicine Center after both the first and the second waves. ELISA-based tests for anti-SARS-CoV-2 IgA and IgG were used to determine immune response to SARS-CoV-2 in volunteer HCWs who worked in those institutions in May 2020 (208 participants aged 47.1 ± 12.5, 88% women) and in December 2020 (179 participants aged 45.2 ± 12.4, 86% woman). Risk factors for seropositivity were also assessed using a questionnaire filled out by all participants. We reported a significant increase in seroprevalence after the second wave (22.9%) compared with the first outbreak (2.4%) (OR 12.1; 95%CI 4.6–31.3; p < 0.0001). An association between IgG seroprevalence and severity of infections was noted. Furthermore, we demonstrated that amongst medical personnel, nurses exhibited a proportionally higher SARS-CoV-2 seroprevalence. Moreover, given the high seroprevalence in non-clinical group of HCWs, we suggest that community transmission can play a superior role to workplace exposure.

Seroprevalence of SARS-CoV-2 antibodies in the general population of Oman: results from four successive nationwide sero-epidemiological surveys

ObjectiveTo assess the seroprevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in Oman and longitudinal changes in antibody levels over time within the first 11 months of the coronavirus disease 2019 (COVID-19) pandemic.MethodsThis nationwide cross-sectional study was conducted as a four-cycle serosurvey using a multi-stage stratified sampling method from July to November 2020. A questionnaire was used and included demographics, history of acute respiratory infection and list of symptoms, COVID-19 contact, previous diagnosis or admission, travel history and risk factors.ResultsIn total, 17,457 participants were surveyed. Thirty percent were female and 66.3% were Omani. There was a significant increase in seroprevalence throughout the study cycles, from 5.5% (4.8–6.2%) in Cycle 1 to 22% (19.6–24.6%) in Cycle 4. There was no difference in seroprevalence between genders, but significant differences were found between age groups. There was a transition of seroprevalence from being higher in non-Omanis than Omanis in Cycle 1 [9.1% (7.6–10.9%) vs 3.2% (2.6–3.9%)] to being higher in Omanis than non-Omanis in Cycle 4 [24.3% (21.0–27.9%) vs 16.8% (14.9–18.9%)]. There was remarkable variation in the seroprevalence of SARS-CoV-2 according to governorate. Close contacts of people with COVID-19 had a 96% higher risk of having the disease [adjusted odds ratio (AOR) 1.96, 95% confidence intervals (CI) 1.64–2.34]. Labourers had 58% higher risk of infection compared with office workers (AOR 1.58, 95% CI 1.04–2.35).ConclusionThis study showed a wide variation in the spread of SARS-CoV-2 across governorates in Oman, with higher estimated seroprevalence in migrants in the first two cycles. Prevalence estimates remain low and are insufficient to provide herd immunity.

A Review on Rubella Vaccine: Iran (1975-2010).

The first Attenuated rubella vaccine was developed by Parkman and Meyer in 1966. Ten years later in the 1975s, the rubella vaccine was developed in Razi Vaccine and serum research institute) RVSRI). In 1977, the rubella TAKAHASHI vaccine successfully passed the clinical trial and was initially used voluntarily only in the private sector. Since 1987, the administration of rubella as MMR (Measles/AIK-C; Rubella/TAKAHASHI; Mumps/HOSHINO) strain vaccine has been included in the immunization program in Iran. This review article focused on the development and production of the rubella TAKAHASHI/HDC vaccine in RVSRI. The herd immunity and rubella cases were investigated in the pre- and post-vaccine era. The effectiveness and proper coverage of the rubella vaccine led to the elimination of rubella from Iran in 2019. The current study aimed to assess local rubella vaccine manufacturing and its consequences on rubella elimination from Iran, using various search engines. A complete search was carried out in medical databases, including PubMed, Scopus, Web of Science, Scientific Information Database, IranMedex, Magiran, and Google Scholar. Within 1972-1975, Rubella TAKAHASHI/HDC vaccine was developed by RVSRI and successfully passed clinical trial in 1977. Over the four last decades (1980-2020), more than 40 million infants, young, and adults were vaccinated by million doses of local Rubella, measles-rubella (MR) or measles-mumps-rubella (MMR) vaccine in Iran. In 1972, the pre-vaccine era, the overall sensitivity to rubella infection was 69% in one-year-old Iranian children and 23% in childbearing women. The use of a safe, inexpensive, and effective vaccine increased herd immunity to 95% (85%-99%) in our country. During the last two decades, we have witnessed a 91% decline in the confirmed rubella cases, from 1124 in 2000 to 33 cases in 2018. The current article presented the process of vaccine development, tracked it through more than four decades, and discussed disease status before and after the rubella vaccine era, as well as the history of its elimination from Iran. The effectiveness of the local Razi Rubella vaccine resulted in a significant increase in seroprevalence in Iran. Expanded vaccination against rubella, usually with measles, has led to the elimination of Rubella from Iran as confirmed by World Health Organization in 2019.

Changes in Severe Acute Respiratory Syndrome Coronavirus 2 Seroprevalence Over Time in 10 Sites in the United States, March-August, 2020.

Background Monitoring of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody prevalence can complement case reporting to inform more accurate estimates of SARS-CoV-2 infection burden, but few studies have undertaken repeated sampling over time on a broad geographic scale.Methods We performed serologic testing on a convenience sample of residual sera obtained from persons of all ages, at ten sites in the United States from March 23 through August 14, 2020, from routine clinical testing at commercial laboratories. We age-sex-standardized our seroprevalence rates using census population projections and adjusted for laboratory assay performance. Confidence intervals were generated with a two-stage bootstrap. We used Bayesian modeling to test whether seroprevalence changes over time were statistically significant.Results Seroprevalence remained below 10% at all sites except New York and Florida, where it reached 23.2% and 13.3%, respectively. Statistically significant increases in seroprevalence followed peaks in reported cases in New York, South Florida, Utah, Missouri and Louisiana. In the absence of such peaks, some significant decreases were observed over time in New York, Missouri, Utah, and Western Washington. The estimated cumulative number of infections with detectable antibody response continued to exceed reported cases in all sites.Conclusions Estimated seroprevalence was low in most sites, indicating that most people in the U.S. have not been infected with SARS-CoV-2 as of July 2020. The majority of infections are likely not reported. Decreases in seroprevalence may be related to changes in healthcare-seeking behavior, or evidence of waning of detectable anti-SARS CoV-2 antibody levels at the population level. Thus, seroprevalence estimates may underestimate the cumulative incidence of infection.

Trends of Seroprevalence of Chagas´s diseases in healthy blood donors, solid organ donors and heart transplant recipients: experience of a single health care center in Colombia.

The prevalence of Chagas disease has decreased in the Americas region due to vector control measures. However, non-vectorial transmission through blood transfusions and organ transplantation has gained importance in recent years. Screening among blood and organ donors are essential to reduce Trypanosoma cruzi transmission and could provide information to estimate population prevalence. We conducted a cross-sectional study on the prevalence of immunoglobulin G (IgG) antibodies against T. cruzi in healthy blood donors, solid organ donors and heart transplant recipients from 2012 to 2019. We found a total of 99 357 IgG T. cruzi results during the study period. The cumulative seroprevalence in healthy blood donors was 0.13% (95% confidence interval (CI) 0.10–0.15), in organ donors was 0.53% (95% CI 0.06–1.92) and in heart transplant recipients was 3.03 (95% CI 0.07–15.75). Seroprevalence trend in healthy blood donors showed annual increase between 2012 and 2015, decreasing in the following years. No trend was seen in organ donors neither heart recipients. Adjusted rates did not show difference by sex and age among blood donors. No significant increases in seroprevalence T. cruzi were found during the study period. T. cruzi transmission remains low.

Monitoring of Pseudorabies in Wild Boar of Germany-A Spatiotemporal Analysis.

To evaluate recent developments regarding the epidemiological situation of pseudorabies virus (PRV) infections in wild boar populations in Germany, nationwide serological monitoring was conducted between 2010 and 2015. During this period, a total of 108,748 sera from wild boars were tested for the presence of PRV-specific antibodies using commercial enzyme-linked immunosorbent assays. The overall PRV seroprevalence was estimated at 12.09% for Germany. A significant increase in seroprevalence was observed in recent years indicating both a further spatial spread and strong disease dynamics. For spatiotemporal analysis, data from 1985 to 2009 from previous studies were incorporated. The analysis revealed that PRV infections in wild boar were endemic in all German federal states; the affected area covers at least 48.5% of the German territory. There were marked differences in seroprevalence at district levels as well as in the relative risk (RR) of infection of wild boar throughout Germany. We identified several smaller clusters and one large region, where the RR was two to four times higher as compared to the remaining areas under investigation. Based on the present monitoring intensity and outcome, we provide recommendations with respect to future monitoring efforts concerning PRV infections in wild boar in Germany.

Seroprevalence of human toxocarosis in Europe: A review and meta-analysis.

Toxocarosis is distributed worldwide and represents the most prevalent zoonotic helminth infection in industrialized countries, thereby posing a substantial risk for public health. Thus, toxocarosis is one of CDC's Neglected Parasitic Infections that has been targeted for public health action. This systematic review and meta-analysis summarizes Toxocara seroprevalence in general populations from Europe, populations suspected of Toxocara infection and defined risk groups. Random-effects meta-analysis of proportions based on 41 publications resulted in an overall seroprevalence of 6.2% (95% CI: 4.7-8.3%) in the general population of Europe. Subgroup analysis according to decades (1970-2010s) revealed a significant increase in seroprevalence, with the highest value (12.4%; 95% CI: 6.5-22.3%) in the 2010s (χ2=17.87, df=4, P=0.001). There were no significant differences between pooled prevalence rates of European sub-regions (χ2=3.01, df=3, P=0.389). Furthermore, meta-analysis of seroprevalence according to age groups, based on data from 22 publications, indicated a significantly higher pooled seroprevalence of 14.9% (95% CI: 8.5-24.8%) in people more than 50 years of age than in younger age cohorts (χ2=8.33, df=2, P=0.016). Occupational groups exposed to contaminated soil and infected animals bear substantial risk for acquiring Toxocara infection. Due to the close link between animal infection and human Toxocara exposure, a "One Health" approach for the prevention of Toxocara infection in both humans and animals is required.

The investigation of seroprevalence of Borrelia burgdorferi and Rickettsia conorii in people living in forest villages of Sinop

Objective: This study aimed to investigate the seroprevalence of Borrelia burgdorferi , the causative agent of Lyme disease, and Rickettsia conorii , the causative agent of Mediterranean spotted fever, in the Sinop region. Method: In 2006 and 2007, the blood serum of 184 people, living in the villages of the central district of Sinop, was obtained and stored at 80ºC until the study. In these sera, IgG antibodies reactive to B. burgdorferi and R. conorii were investigated by ELISA method. Results: Antibody positivity was found against B. burgdorferi in 36.41% and R. conorii in 45.10% of 184 people living in rural areas of Sinop. Reactive antibodies against B. burgdorferi were detected in 47.62% of 42 people with a history of redness and swelling at the contact site after the tick bite, and in 28.95% of 76 people without these symptoms (p= 0.043, OR=2.23) . The seropositivity to R. conorii was found in 57.14% and 46.05% of persons with and without these symptoms, respectively (p= 0.363, OR= 1.56). There was a statistically significant increase in seroprevalence of both B. burgdorferi and R. conorii with increasing age (p<0.05). R. conorii and B. burgdorferi co-seroprevalence were determined in 16.85% of serum samples. Since the ELISA test results in both pathogens were not repeated with confirmation tests, these findings were considered possible. Conclusions: The findings obtained in this study revealed that Sinop and similar ecological features should be evaluated within the endemic regions for B. burgdorferi and R. conorii . It should be paying attention that infections from both pathogens may be likely to appear at these regions.

Prevalence of Borrelia burgdorferi, Anaplasma spp., Ehrlichia spp. and Dirofilaria immitis in Canadian dogs, 2008 to 2015: a repeat cross-sectional study

BackgroundVector-borne pathogens are emerging concerns in multiple regions of Canada. Determining regional prevalence of canine vector-borne pathogens and documenting change will improve clinician awareness, enable targeted prevention, enhance diagnosis and ideally reduce the risk of disease. Study objectives were to: (i) estimate the prevalence of positive canine vector-borne test results from samples submitted in Canada; (ii) assess change in prevalence over time, from baseline (2008) to 2015; and (iii) estimate the prevalence of pathogen co-infections.MethodsThis repeat cross-sectional study evaluated 753,468 test results for D. immitis antigen and B. burgdorferi, Ehrlichia canis/ewingii/muris serology, and 753,208 test results for Anaplasma phagocytophilum/platys serology using the SNAP® 4Dx®Test and SNAP 4Dx® Plus Test.ResultsBased on all submitted samples from Canada (2008–2015), the period seroprevalence of B. burgdorferi, Ehrlichia spp., Anaplasma spp. and D. immitis antigen were 2.0%, 0.5%, 0.4% and 0.2%, respectively. Over the 7 years (2008 compared to 2015) we observed a significant increase in seroprevalence for B. burgdorferi (144.4%) and Ehrlichia spp. (150%). Co-infections (positive for two or more pathogens on a single 4 pathogen test kit) were estimated at 5.4% (1162/21,612) of total positive tests.ConclusionsThe temporal rise and geographical differences in prevalence detected for these pathogens (notably B. burgdorferi) are consistent with anecdotal information on canine illness related to tick-borne pathogen exposure in multiple regions of Canada, particularly canine Lyme disease.

Seroprevalence of dengue virus in two districts of Kaohsiung City after the largest dengue outbreak in Taiwan since World War II.

Dengue virus (DENV) is the leading cause of arboviral diseases in humans worldwide. In this study, we investigated the seroprevalence of DENV infection in two districts of Kaohsiung City, a metropolis in southern Taiwan, where major dengue outbreaks have occurred in the past three decades. We enrolled 1,088 participants from the Sanmin and Nanzih districts after the dengue outbreak of 2015, the largest in Taiwan since World War II, and found an overall DENV seroprevalence of 12.4% (95% confidence interval: 10.5–13.4%) based on the InBios DENV IgG ELISA kit. The ratios of clinically inapparent to symptomatic infections were 2.86 and 4.76 in Sanmin and Nanzih districts, respectively. Consistent with higher case numbers during recent outbreaks, the DENV seroprevalence was higher in Sanmin district (16.4%) than in Nanzih district (6.9%), suggesting district differences in seroprevalence and highlighting the importance of screening the DENV immune status of each individual before using the currently available DENV vaccine, Dengvaxia. In the two districts, the seroprevalence rates increased from 2.1% (in the 30–39-year age group) to 17.1% (60–69) and 50% (70–79). The pattern of a sharp and significant increase in seroprevalence in the 70–79-year age group correlated with a dramatic increase in the proportion of clinically severe DENV infections among total dengue cases in that age group. This differed from observations in the Americas and Southeast Asia and suggested that a large proportion of monotypically immune individuals together with other risk factors may contribute to clinically severe dengue among the elderly in Taiwan.

Differential Prevalence of Antibodies Against Adeno-Associated Virus in Healthy Children and Patients with Mucopolysaccharidosis III: Perspective for AAV-Mediated Gene Therapy.

Recombinant adeno-associated virus (AAV) vectors are promising gene therapy tools. However, pre-existing antibodies (Abs) to many useful AAV serotypes pose a critical challenge for the translation of gene therapies. As part of AAV gene therapy program for treating mucopolysaccharidosis (MPS) III patients, the seroprevalence profiles of AAV1-9 and rh74 were investigated in MPS IIIA/IIIB patients and in healthy children. Using enzyme-linked immunosorbent assay for αAAV-IgG, significantly higher seroprevalence was observed for AAV1 and AAVrh74 in 2- to 7-year-old MPS III patients than in healthy controls. Seroprevalence for the majority of tested AAV serotypes appears to peak before 8 years of age in MPS III subjects, with the exception of increases in αAAV8 and αAAV9 Abs in 8- to 19-year-old MPS IIIA patients. In contrast, significant increases in seroprevalence were observed for virtually all tested AAV serotypes in 8- to 15-year-old healthy children compared to 2- to 7-year-olds. Co-prevalence and Ab level correlation results followed the previously established divergence-based clade positions of AAV1-9. Interestingly, the individuals positive for αAAVrh74-Abs showed the lowest co-prevalence with Abs for AAV1-9 (22-40%). However, all or nearly all (77-100%) of subjects who were seropositive for any of serotypes 1-9 were also positive for αAAVrh74-IgG. Notably, the majority (78%) of αAAV seropositive individuals were also Ab-positive for one to five of the tested AAV serotypes, mostly with low levels of αAAV-Abs (1:50-100), while a minority (22%) were seropositive for six or more AAV serotypes, mostly with high levels of αAAV-IgG for multiple serotypes. In general, the highest IgG levels were reactive to AAV2, AAV3, and AAVrh74. The data illustrate the complex seroprevalence profiles of AAV1-9 and rh74 in MPS patients and healthy children, indicating the potential association of AAV seroprevalence with age and disease conditions. The broad co-prevalence of Abs for different AAV serotypes reinforces the challenge of pre-existing αAAV-Abs for translating AAV gene therapy to clinical applications, regardless of the vector serotype.

Cytomegalovirus infection in a cohort of pregnant women

Enzyme linked immunosorbent assay was used to detect the seroprevalence of cytomegalovirus (CMV) immunoglobulin M (IgM) and immunoglobulin G (IgG) in 300 pregnant women. Seventeen (5.7%) and 274 (91.3%) women were seropositive for IgM and IgG, respectively. There was significant increase in seroprevalence of CMV IgG and no significant increase in seroprevalence of CMV IgM among tested age groups. CMV IgM and IgG seroprevalence differed nonsignificantly by type of residence, the stage of pregnancy, and the level of education.

A 10 Years Comparative Study to Assess Trends in Seroprevalence of Transfusion Transmitted Infections among Blood Donors at Gwalior, India

Introduction: Transfusion Transmitted Infections (TTIs) threaten safety of the recipients and the community as a whole and are the subject of real concern worldwide. Aims and Objectives: To know the prevalence of transfusion transmitted infections amongst the blood donors, to evaluate the changing trends of TTIs and to compare these observations within the study as well as with the other relevant studies. Place and Duration of Study: This study was carried out at Blood Bank, Department of Pathology, Gajra Raja Medical College, Gwalior, India, from January 2004 to December 2013 (ten years). Materials and Methods: In this study 122,006 voluntary and replacement donations were screened for TTIs; HIV, HBV, HCV, Syphilis, Malaria and their seroprevalence was calculated. Further study was divided in Group “A” (from 2004 to 2008) and Group “B” (from 2009 to 2013) to compare the results. Results: Out of total 122,006 blood units collected, 79,750 (65.3%) were voluntary and 42,256 (34.7%) were replacement donors. The seropositivity of TTIs in the entire study, in group “A” and in Group “B” was 3.26% (3985/122,006) (p = 0.000005), 2.25% (1238/54,874) (p = 0.000005) and 4.09% (2747/67,123) (p = 0.000005) respectively. In Group “A” and “B” seroprevalence of HIV, HBV, HCV, Syphilis and Malaria was 0.29%, 1.16%, 0.61%, 0.06%, 0.11% and 0.13%, 3.15%, 0.24%, 0.17%, 0.03% respectively. Conclusion: Our study concluded that there was significant increase in seroprevalence of HBV and syphilis whereas decreasing pattern in HIV, HCV and Malaria was observed in last five years as compared to previous five years among the blood donors.

Detection of canine pneumovirus in dogs with canine infectious respiratory disease.

Canine pneumovirus (CnPnV) was recently identified during a retrospective survey of kenneled dogs in the United States. In this study, archived samples from pet and kenneled dogs in the United Kingdom were screened for CnPnV to explore the relationship between exposure to CnPnV and the development of canine infectious respiratory disease (CIRD). Within the pet dog population, CnPnV-seropositive dogs were detected throughout the United Kingdom and Republic of Ireland, with an overall estimated seroprevalence of 50% (n = 314/625 dogs). In the kennel population, there was a significant increase in seroprevalence, from 26% (n = 56/215 dogs) on the day of entry to 93.5% (n = 201/215 dogs) after 21 days (P <0001). Dogs that were seronegative on entry but seroconverted while in the kennel were 4 times more likely to develop severe respiratory disease than those that did not seroconvert (P < 0.001), and dogs with preexisting antibodies to CnPnV on the day of entry were significantly less likely to develop respiratory disease than immunologically naive dogs (P < 0.001). CnPnV was detected in the tracheal tissues of 29/205 kenneled dogs. Detection was most frequent in dogs with mild to moderate respiratory signs and histopathological changes and in dogs housed for 8 to 14 days, which coincided with a significant increase in the risk of developing respiratory disease compared to the risk of those housed 1 to 7 days (P < 0.001). These findings demonstrate that CnPnV is present in the United Kingdom dog population; there is a strong association between exposure to CnPnV and CIRD in the kennel studied and a potential benefit in vaccinating against CnPnV as part of a wider disease prevention strategy.

Séroprévalence de la rubéole chez la femme en âge de procréer deux ans après l’introduction de la vaccination en Tunisie

Acquiring rubella during the first 20weeks of pregnancy can lead to teratogenic effects. AimThe aim of the study was to investigate the impact of rubella vaccination strategy two years after its introduction in Tunisia in 2005. MethodsThis study was conducted over two periods, 2000 and 2007–2008. A total of 15,776 childbearing women were enrolled in the sample. Serological studies were performed by using the ELISA method. ResultsOverall, rubella infection seroprevalence did not increase between 2000 and 2007–2008. Nevertheless, a significant increase in seroprevalence, from 78.2% in 2000 to 92% in 2007–2008 (P=0.006), was especially noted in the age group under 20years. Seroprevalence did also statistically increase with parity in 2007–2008 from 77.4% in women without any parity to 89.8% in women with over three parities (P=0.01). ConclusionsResults improvements seem most likely due to mass vaccination campaign for girls aged from 13 to 18years in 2005, and also routinely post-partum vaccination of seronegative pregnant women or women ignoring their rubella status. In the coming years, systematic selective immunization of 12-year-old schoolgirls who are not yet entering their prime childbearing years will achieve female population sufficient immunity.

Development and use of an indirect ELISA in an outbreak of bovine besnoitiosis in Spain

An indirect ELISA based on a soluble extract of Besnoitia besnoiti tachyzoites was developed and standardised. A set of positive and negative reference bovine sera were characterised using an immunofluorescence...

Influence of oral rabies vaccine bait density on rabies seroprevalence in wild raccoons

The effect of different oral rabies vaccine (ORV) bait densities (75, 150, and 300baits/km2) on the seroprevalence of rabies virus neutralizing antibodies (RVNAs) in raccoons (Procyon lotor) was assessed at a 15% seroprevalence difference threshold in rural areas of northeast Ohio. Results (n=588 raccoons) indicated that seropositivity for RVNAs was associated with both bait density and bait campaign frequency. Associations were not detected for raccoon gender, age, or macro-habitat. The odds of being seropositive were greater for raccoons originating from 300bait/km2 treatment areas relative to those coming from the 75bait/km2 areas (odds ratio [OR]=4.4, probability [P]<0.001, 95% confidence interval [CI]=2.4–7.9), while accounting for cumulative ORV campaigns. No statistical advantage in seroprevalence was detected when comparing 150–75baits/km2. These results indicate that a relatively extreme bait density when evenly distributed may be necessary to obtain a significant increase in seroprevalence. Higher bait densities may be more appropriate and less costly to address focused outbreaks than labor intensive trap-vaccinate-release and local population reduction campaigns. Finally, dramatic increases in seroprevalence of RVNA were not observed in raccoons between sequential, semi-annual campaigns, yet cumulative ORV campaigns were associated with gradual increases in seroprevalence.

Temporal trends in hepatitis B and C infection in family blood donors from interior Sindh, Pakistan

BackgroundHepatitis B (HBV) and C (HCV) infections are a serious global and national public health problem. Earlier studies have reported increasing rates of hepatitis infection in Pakistan, particularly in rural areas. Pakistan has no active surveillance program to monitor trends of these infections. The objective of this study was to verify this trend in blood donors from the rural Sindh area of the country.MethodsThe study analysed the data of blood donors of interior Sindh who donated blood at JPMC blood bank from January 1, 2004 to September 15, 2007. HBsAg status was determined by using HBsAg Serodia kit and antibodies to HCV using the Detect HCV ™ V.3 Kit. Samples repeatedly reactive for HBsAg or anti-HCV were considered positive for HBV or HCV infection respectively.ResultsThe overall seroprevalence of HBV infection among donors was 6.2 % (95% CI 5.5%–6.9%) and did not change significantly over the study period. Overall seroprevalence of HBV infection in literate blood donors was 5.7 %(95% CI 4.7%–6.8%). Prevalence decreased significantly in this group over the study period (p = 0.05). No other significant trends in seroprevalence of HBV infection were seen in the stratified analyses.The overall seroprevalence of HCV among donors was 7.5% (95% CI 6.8%–8.3%) and increased significantly over the study period from 7.2% (95% CI 5.8%–8.7%) in 2004 to 8.9% (95% CI 7.4%–10.6%) in 2007 (p = 0.02). Significant increase in seroprevalence was particularly seen in literate (p = 0.03), non–first time (p = 0.01) and Sindhi speaking (p = 0.01) donors.ConclusionOur study finds a steady increase in the prevalence of HCV infection in blood donors from interior Sindh between 2004 and 2007. On the contrary, decreasing prevalence of HBV was found, particularly in literate blood donors. There may be a need to have rural community-based epidemiological studies to identify the determinants of the spread of HCV infection and also those that are limiting the spread of HBV infection particularly in the literate blood donor population.