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Background Tick distribution in Sweden has increased in recent years, with the prevalence of ticks predicted to spread towards the northern parts of the country, thus increasing the risk of tick-borne zoonoses in new regions. Tick-borne encephalitis (TBE) is the most significant viral tick-borne zoonotic disease in Europe. The disease is caused by TBE virus (TBEV) infection which often leads to severe encephalitis and myelitis in humans. TBEV is usually transmitted to humans via tick bites; however, the virus can also be excreted in the milk of goats, sheep and cattle and infection may then occur via consumption of unpasteurised dairy products. Virus prevalence in questing ticks is an unreliable indicator of TBE infection risk as viral RNA is rarely detected even in large sample sizes collected at TBE-endemic areas. Hence, there is a need for robust surveillance techniques to identify emerging TBEV risk areas at early stages. Methods Milk and colostrum samples were collected from sheep and goats in orebro County, Sweden. The milk samples were analysed for the presence of TBEV antibodies by ELISA and validated by western blot in which milk samples were used to detect over-expressed TBEV E-protein in crude cell extracts. Neutralising titers were determined by focus reduction neutralisation test (FRNT). The stability of TBEV in milk and colostrum was studied at different temperatures. Results In this study we have developed a novel strategy to identify new TBEV foci. By monitoring TBEV antibodies in milk, we have identified three previously unknown foci in orebro County which also overlap with areas of TBE infection reported during 2009-2018. In addition, our data indicates that keeping unpasteurised milk at 4 degrees C will preserve the infectivity of TBEV for several days. Conclusions Altogether, we report a non-invasive surveillance technique for revealing risk areas for TBE in Sweden, by detecting TBEV antibodies in sheep milk. This approach is robust and reliable

The zoonotic Rift Valley fever virus affects livestock and humans in Africa and on the Arabian Peninsula. The economic impact of this pathogen due to livestock losses, as well as its relevance to public health, underscores the importance of developing effective and easily distributed vaccines. Vaccines that can be delivered orally are of particular interest. Here, we report the expression in transformed plants (Arabidopsis thaliana) of Rift Valley fever virus antigens. The antigens used in this study were the N protein and a deletion mutant of the Gn glycoprotein. Transformed lines were analysed for specific mRNA and protein content by RT-PCR and Western blotting, respectively. Furthermore, the plant-expressed antigens were evaluated for their immunogenicity in mice fed the transgenic plants. After oral intake of fresh transgenic plant material, a proportion of the mice elicited specific IgG antibody responses, as compared to the control animals that were fed wild-type plants and of which none sero-converted. Thus, we show that transgenic plants can be readily used to express and produce Rift Valley Fever virus proteins, and that the plants are immunogenic when given orally to mice. These are promising findings and provide a basis for further studies on edible plant vaccines against the Rift Valley fever virus.

Background: Despite the fact that HIV-positive women carry an increased risk of developing cervical cancer (CC) in comparison with HIV-negative women, HIV and CC screening programs in many developing countries have remained unintegrated. The objective of this study is to explore perceptions and preferences of community members in Uganda, including women, men, and village health teams, regarding the integration of HIV and CC screening services in a single-visit approach. Methods: This qualitative study was conducted in three districts in Uganda. Data were collected through focus group discussions with women and village health teams, and individual interviews with men. Respondents were purposely selected from among those linked to three CC clinics in the three districts. The content analysis method was used to analyze the data. Results: Three themes emerged from the data, namely appreciating the benefits of integration, worrying about the challenges of integration, and preferences for integration. The women endorsed the benefits. However, there were worries that integration would prolong the waiting time at the health facility and induce tiredness in both the healthcare providers and the women. There were also fears of being found positive for both HIV and CC and the consequences such as stress, self-isolation, and social conflicts. Participants, particularly the women, considered the challenges of screening integration to be manageable by, for example, taking a day off work to visit the hospital, delegating house chores to other family members, or taking a packed lunch on visiting the hospital. Conclusions: The community members in Uganda perceive the benefits of HIV and CC screening integration to outweigh the challenges, and expect that the challenges can be minimized or managed by the women. Therefore, when considering HIV and CC screening integration, it is important to not only recognize the benefits but also take into consideration the perceived challenges and

Objective: To investigate the human papillomavirus (HPV) and HPV type 16-variant distribution in a series of vulvar squamous cell carcinomas (VSCC) and to evaluate the impact of HPV and HPV 16-variant on prognosis. Methods: A series of 133 patients who had a diagnosis of VSCC (1983-2008) was selected for the study. Detection of 11 high-risk HPV types (16, 18, 31, 33, 39, 45, 51, 52, 56, 58, and 59) and 2 low-risk HPV types (6 and 11) was performed with real-time polymerase chain reaction. Samples positive for HPV 16 were further analyzed for variant determination of 7 positions in the E6 gene with polymerase chain reaction and pyrosequencing. Results: Forty (30.8%) of 130 tumors were found to be HPV positive. Human papillomavirus type 16 was found in 31 cases, HPV 18 was found in 2 cases, HPV 33 was found in 5 cases, and HPV 56 and HPV 59 were found in one case each. All but one tumor harboring HPV 16 were of European linage, and the 3 most common variants were E-p (n = 13), E-G350 (n = 7), and E-G131 (n = 5). HPV positivity was associated with the basaloid tumor type and occurred in significantly younger patients. Overall and recurrence-free survival rates were better in HPV-positive cases, but after correction for age and tumor size, HPV status was no longer an independent and significant prognostic factor. The survival rates of the various HPV 16 variants were not significantly different, but there was a trend of worse outcome for the E-G131-variant group. Conclusions: Human papillomavirus positivity of 30.8% is similar to other reports on VSCC. To our knowledge, this first variant determination of HPV 16 in vulvar carcinoma in a Swedish cohort indicated that the variant E-G131 may have an increased oncogenic potential in patients with VSCC.

Background: Prevalence data on human T-lymphotropic virus types 1 and 2 (HTLV-1/2) in Sweden have not been updated since 1995. The seroprevalence among blood donors at that time was 0.2/10,000. A few years earlier, a high prevalence of HTLV-2 was found in intravenous drug users (IDUs) in Stockholm (3.4%). The objective of this study was to update information on the seroprevalence of HTLV in several study groups. Methods: Serum samples from pregnant women, hepatitis C virus (HCV)-positive individuals, and IDUs in Stockholm were investigated for HTLV-1/2 antibodies. Data from the mandatory HTLV-1/2 screening (2003-2006) of in vitro fertilization (IVF) clients were compiled, as well as data from new blood donors. Results: Eight out of 35,000 IVF patients were positive for anti-HTLV-1/2 (seroprevalence 2.3 per 10,000). Of the anti-HCV-positive individuals (n = 355), 1 sample was HTLV-1-positive (28.2 per 10,000). From 1995 to 2007, 18 HTLV-positive new blood donors were identified out of approximately 550,000 individuals tested (0.3 per 10,000). Thirty-five of 1079 tested IDUs were screening reactive. Conclusions: Since the start of screening in 1994, there has been no increased seroprevalence of HTLV-1/2 among blood donors in Sweden. Seroprevalence among Swedish IVF patients is 10 times higher than among blood donors. This finding is comparable to a 2003 European seroprevalence study of pregnant women in 7 countries. However, the possibility that the IVF group includes individuals with a higher risk of acquiring sexually transmitted infections, including HTLV, than the general population cannot be ruled out.

Background: Survival of people with HIV-2 and HTLV-1 infection is better than that of HIV-1 infected people, but long-term follow-up data are rare. We compared mortality rates of HIV-1, HIV-2, and HTLV-1 infected subjects with those of retrovirus-uninfected people in a rural community in Guinea-Bissau. Methods: In 1990, 1997 and 2007, adult residents (aged >= 15 years) were interviewed, a blood sample was drawn and retroviral status was determined. An annual census was used to ascertain the vital status of all subjects. Cox regression analysis was used to estimate mortality hazard ratios (HR), comparing retrovirus-infected versus uninfected people. Results: A total of 5376 subjects were included; 197 with HIV-1, 424 with HIV-2 and 325 with HTLV-1 infection. The median follow-up time was 10.9 years (range 0.0-20.3). The crude mortality rates were 9.6 per 100 person-years of observation (95% confidence interval 7.1-12.9) for HIV-1, 4.1 (3.4-5.0) for HIV-2, 3.6 (2.9-4.6) for HTLV-1, and 1.6 (1.5-1.8) for retrovirus-negative subjects. The HR comparing the mortality rate of infected to that of uninfected subjects varied significantly with age. The adjusted HR for HIV-1 infection varied from 4.0 in the oldest age group (>= 60 years) to 12.7 in the youngest (15-29 years). The HR for HIV-2 infection varied from 1.2 (oldest) to 9.1 (youngest), and for HTLV-1 infection from 1.2 (oldest) to 3.8 (youngest). Conclusions: HTLV-1 infection is associated with significantly increased mortality. The mortality rate of HIV-2 infection, although lower than that of HIV-1 infection, is also increased, especially among young people.

Development of transgenic edible plants, to be used as production, storage and delivery systems for recombinant vaccine antigens, is a promising strategy to obtain cost effective vaccines against infectious diseases, not least for use in developing countries. Therefore, we used Agrobacterium tumefaciens-mediated gene transfer to introduce the p24 gag gene encoding the nucleocapsid protein from HIV-1 subtype C into the Arabidopsis thaliana plant genome. Eighteen plant lines were confirmed positive for the p24 gene by PCR; four of these lines showed an apparent homozygous phenotype when grown on selective medium and these lines also showed transcription of the p24 gene into its corresponding mRNA. The mRNA in all four cases generated the p24 protein in plants, as verified by Western blot analysis. The plants were shown to contain between 0.2 mu g and 0.5 mu g p24 protein per g of fresh tissue. Analysis of the localisation of the p24 protein showed that stem tissue contained the largest amount of protein, more than twice as much as leaf tissue, whereas no p24 protein was detected in roots. By using Southern blotting, we found that 4, 2-3, 2 and 1 T-DNA insertion events took place in the four lines 1, 2, 7, and 10, respectively. The genetic insertions of line 1 were stable from the T-2 to the T-5 generation and gave rise to the p24 protein in all cases, as verified by Western blotting. In mice fed with fresh transgenic A. thaliana (line 10), anti-gag IgG was obtained in serum after a booster injection with recombinant p37Gag. No immune response was observed after equal booster injection of untreated mice or mice fed with A. thaliana WT plants., The definitive version is available at www.blackwell-synergy.com:Ingrid Lindh, Irina Kalbina, Sara Thulin, Nikolai Scherbak, Helena Savenstrand, Andreas Brave, Jorma Hinkula, Ake Strid and Soren Andersson, Feeding of mice with Arabidopsis thaliana expressing the HIV-1 subtype C p24 antigen gives rise to systemic immune responses, 2008, APMIS, (116), 11, 985-994.http://dx.doi.org/10.1111/j.1600-0463.2008.00900.xCopyright: Blackwell Publishing Ltdhttp://www.blackwellpublishing.com

BACKGROUND: Screening of blood donors for markers of transfusion-transmissible infectious agents leads to a varying number of false-reactive test results and sometimes thereby temporary or permanent deferral of donors and also to loss of collected units. STUDY DESIGN AND METHODS: Data on false-reactive screening test results in 2002 and 2003 were collected from 19 blood centers in Sweden. A questionnaire was sent to donors deferred because of false-reactive screening test results to investigate their perception of the information and their reaction to the deferral. RESULTS: Testing of 21,189 samples from new donors and 423,543 donations from regular and/or repeat donors produced 1,059 false-reactive test results, mostly from hepatitis C virus antibody testing, and 299 deferrals. Six different human immunodeficiency virus tests led to between 0.02 and 0.2 percent false-reactive results. The deferral rate varied considerably between different counties. Of 204 deferred donors contacted, 180 (88%) answered the questionnaire. More than 80 percent were worried about their test results and worry was more common among those who did not feel sufficiently informed. CONCLUSION: The results imply that there is a need for a more standardized approach to the screening of blood donors and donations with the aim of minimizing the number of false-reactive screening test results. They also emphasize the importance of appropriate information and support to deferred donors.

BACKGROUND: Up to 20 million persons are infected with the human retroviruses human T-lymphotropic virus (HTLV)-I and HTLV-II globally. Most data on the seroprevalence of HTLV-I and HTLV-II in Europe are from studies of low-risk blood donors or high-risk injection drug users (IDUs). Little is known about the general population. METHODS: A prospective anonymous study of HTLV-I and HTLV-II seroprevalence among 234,078 pregnant women in Belgium, France, Germany, Italy, Portugal, Spain, and the United Kingdom was conducted. Maternal antibody status was determined by standard methods using sera obtained for routine antenatal infection screens or eluted from infant heel prick dried blood spots obtained for routine neonatal metabolic screens. RESULTS: Anti-HTLV-I/II antibodies were detected and confirmed in 96 pregnant women (4.4 per 10,000, 95% confidence interval [CI]: 3.5-5.2). Of these, 73 were anti-HTLV-I, 17 were anti-HTLV-II, and 6 were specifically anti-HTLV but untyped. The seroprevalence ranged from 0.7 per 10,000 in Germany to 11.5 per 10,000 in France. CONCLUSIONS: Pregnant women better reflect the general population than blood donors or IDUs. The seroprevalence of HTLV-I and HTLV-II in Western Europe is 6-fold higher among pregnant women (4.4 per 10,000) than among blood donors (0.07 per 10,000). These data provide a robust baseline against which changes in HTLV-I and HTLV-II seroprevalence in Europe can be measured.