Effectiveness of varying number of doses and timing between doses of quadrivalent HPV vaccine against severe cervical lesions.

BACKGROUND: Based on immunogenicity studies, a 2 dose HPV vaccination-schedule was recently recommended for girls younger than 15 years. We aimed to investigate the effectiveness of quadrivalent HPV (qHPV) vaccination against CIN2 or worse (CIN2+), by age at vaccination, number of doses, and to test whether optimal timing of 2 doses of qHPV vaccine can confer the same level of protection as the originally recommended three dose-schedule. METHODS: A population-based cohort of all women aged 13-30 years, living in Denmark or Sweden during 2006-2013, was followed for qHPV vaccination status and first occurrence of CIN2+. RESULTS: The study cohort comprised 2,253,561 women, of which 33% were vaccinated during follow-up, and 1.7% were diagnosed with CIN2+. Vaccination at ages 13-16 and 17-19 was associated with a reduced risk of CIN2+ after 3 doses (IRR = 0.23, 95% CI 0.11-0.49, and IRR = 0.65, 95% CI 0.41-1.03, respectively), compared to being unvaccinated. After 1 and 2 doses there was a reduced risk, but not statistically significant. Women vaccinated ages 13-16 with 2 doses, where time between first and second dose was 5 months or longer showed no difference in risk compared to 3 doses. CONCLUSIONS: Women vaccinated with 3 doses of qHPV showed a reduced risk of CIN2+ if they were vaccinated before age 20, with a further reduced risk if vaccinated before age 17. Vaccination with 2 doses, with the second dose 5 months or longer after the first dose, did not yield an increased risk of CIN2+, compared to 3 doses.

Estimating effectiveness of HPV vaccination against HPV infection from post-vaccination data in the absence of baseline data.

BACKGROUND: HPV vaccination programs have been introduced in large parts of the world, but monitoring of effectiveness is not routinely performed. Many countries introduced vaccination programs without establishing the baseline of HPV prevalences. We developed and validated methods to estimate protective effectiveness (PE) of vaccination from the post-vaccination data alone using references, which are invariant under HPV vaccination. METHODS: Type-specific HPV prevalence data for 15-39 year-old women were collected from the pre- and post-vaccination era in a region in southern Sweden. In a region in middle Sweden, where no baseline data had been collected, only post-vaccination data was collected. The age-specific baseline prevalence of vaccine HPV types (vtHPV, HPV 6, 11, 16, 18) were reconstructed as Beta distributions from post-vaccination data by applying the reference odds ratios between the target HPV type and non-vaccine-type HPV (nvtHPV) prevalences. Older non-vaccinated age cohorts and the southern Sweden region were used as the references. The methods for baseline reconstructions were validated by computing the Bhattacharyya coefficient (BC), a measure for divergence, between reconstructed and actual observed prevalences for vaccine HPV types in Southern Sweden, and in addition, for non-vaccine types in both regions. The PE estimates among 18-21 year-old women were validated by comparing the PE estimates that were based on the reconstructed baseline prevalences against the PE estimates based on the actual baseline prevalences. RESULTS: In Southern Sweden the PEs against vtHPV were 52.2% (95% CI: 44.9-58.5) using the reconstructed baseline and 49.6% (43.2-55.5) using the actual baseline, with high BC 82.7% between the reconstructed and actual baseline. In the middle Sweden region where baseline data was missing, the PE was estimated at 40.5% (31.6-48.5). CONCLUSIONS: Protective effectiveness of HPV vaccination can be estimated from post-vaccination data alone via reconstructing the baseline using non-vaccine HPV type data.

[Polio close to eradication]. / Polio närmar sig utrotning.

Polio close to eradication The WHO Global Polio Eradication Initiative has been highly successful. With a dramatic decrease in polio since it started in 1988, the number of globally reported cases reached a record low of 37 in 2016. This article describes the WHO Endgame Strategic Plan including milestones that have been reached and challenges that have to be overcome in order to reach the goal of polio eradication by 2020. Efforts to strengthen immunizations systems and to detect and interrupt polio virus transmission focus on the three remaining endemic countries, namely Pakistan, Afghanistan and Nigeria. In 2016 the WHO took the first step to withdraw the oral polio vaccine (OPV) by globally shifting from trivalent to bivalent OPV.  The role of the inactivated vaccine (IPV) in the final phase of eradication and in the post-eradication situation is also considered. Certification of eradication and containment of all polio virus by the end of 2020 is a key objective. Legacy planning includes mainstreaming polio functions into ongoing public health programmes.

Highest Vaccine Uptake after School-Based Delivery - A County-Level Evaluation of the Implementation Strategies for HPV Catch-Up Vaccination in Sweden.

BACKGROUND: The Swedish school-based vaccination programme offers HPV vaccine to girls born ≥1999 in 5-6th grade. In 2012, all counties introduced free-of-charge catch-up vaccination campaigns targeting girls born 1993-1998. Varying vaccine uptake in the catch-up group by December 2012 suggested that some implementation strategies were more successful than others. In order to inform future vaccination campaigns, we assessed the impact of different implementation strategies on the county-level catch-up vaccine uptake. METHODS: We conducted an ecological study including all Swedish counties (n = 21), asking regional health offices about the information channels they used and where vaccination of the catch-up target group took place in their counties. The uptake of ≥1 dose by 30 September 2014 was estimated using data from the voluntary national vaccination register. We investigated associations between counties' catch-up vaccine uptake, information channels and vaccination settings by calculating incidence rate ratios (IRR) and 95% confidence intervals (CI), using negative binomial regression models. RESULTS: County level catch-up vaccine uptake varied between 49-84%. All counties offered vaccination through primary health care settings. Apart from this eight (34%) also offered the vaccine in some of their schools, four (19%) in all their schools, and two (10%) in other health care centres. The information channels most frequently used were: information at the national on-line health care consulting web-page (100%), letter/invitations (90%), and advertisement (81%). Counties offering vaccination to girls in all schools and counties offering vaccination in some of their schools, reached higher vaccine uptake compared to counties not offering vaccination in any of their schools (all schools adjusted IRR: 1.3, 95% CI: 1.1-1.5, some schools adjusted IRR: 1.2, 95% CI: 1.1-1.3). CONCLUSION: Counties offering HPV vaccination to catch-up groups in schools reached the highest vaccine uptake. No information channel explained differences in county-level vaccine uptake. Our findings suggest that catch-up vaccination outside the national vaccination program can reach a high uptake at the population level if it is implemented primarily with an organized delivery (e.g. in schools).

Quadrivalent HPV vaccine effectiveness against high-grade cervical lesions by age at vaccination: A population-based study.

Human papillomavirus (HPV) types 16/18, included in HPV vaccines, contribute to the majority of cervical cancer, and a substantial proportion of cervical intraepithelial neoplasia (CIN) grades 2/3 or worse (CIN2+/CIN3+) including adenocarcinoma in situ or worse. The aim of this study was to quantify the effect of quadrivalent HPV (qHPV) vaccination on incidence of CIN2+ and CIN3+. A nationwide cohort of girls and young women resident in Sweden 2006-2013 and aged 13-29 (n = 1,333,691) was followed for vaccination and histologically confirmed high-grade cervical lesions. Data were collected using the Swedish nationwide healthcare registers. Poisson regression was used to calculate incidence rate ratios (IRRs) and vaccine effectiveness [(1-IRR)x100%] comparing fully vaccinated with unvaccinated individuals. IRRs were adjusted for attained age and parental education, and stratified on vaccination initiation age. Effectiveness against CIN2+ was 64% (IRR = 0.36, 95%CI = 0.27­0.47) for those initiating vaccination before age 17, and 25% (IRR = 0.75, 95%CI = 0.66­0.86) and 14% (IRR = 0.86, 95%CI = 0.73­1.01) for those initiating vaccination at ages 17­19, and at ages 20­29, respectively. Vaccine effectiveness against CIN3+ was similar to vaccine effectiveness against CIN2+. Results were robust for both women participating to the organized screening program and for women at prescreening ages. We show high effectiveness of qHPV vaccination on CIN2+ and CIN3+ lesions, with greater effectiveness observed in girls younger at vaccination initiation. Continued monitoring of impact of HPV vaccination in the population is needed in order to evaluate both long-term vaccine effectiveness and to evaluate whether the vaccination program achieves anticipated effects in prevention of invasive cervical cancer.

The Participation of HPV-Vaccinated Women in a National Cervical Screening Program: Population-Based Cohort Study.

BACKGROUND: Concerns have been raised that HPV-vaccination might affect women's cervical screening behavior. We therefore investigated the association between opportunistic HPV-vaccination and attendance after invitation to cervical screening. METHODS: A cohort of all women resident in Sweden, born 1977-1987 (N=629,703), and invited to cervical screening, was followed October 2006 - December 2012. Invitations to screening were identified via the National Quality Register for Cervical Cancer Prevention, as was the primary outcome of a registered smear. Vaccination status was obtained from two nationwide health data registers. Hazard ratios (HR) were estimated using Cox regression adjusted for age, education level and income (HRadj). Women were individually followed for up to 6 years, of which the first and second screening rounds were analyzed separately. RESULTS: Screening attendance after three years of follow-up was 86% in vaccinated women (N=4,897) and 75% in unvaccinated women (N=625,804). The crude HR of screening attendance in vaccinated vs. unvaccinated women was 1.31 (95% CI 1.27-1.35) in the first screening round. Adjustment for education and income reduced but did not erase this difference (HRadj=1.09, 95% CI 1.05-1.13). In the second screening round, attendance was likewise higher in HPV-vaccinated women (crude HR=1.26, 95% CI 1.21-1.32; HRadj=1.15, 95% CI 1.10-1.20). CONCLUSIONS: HPV-vaccination is so far associated with equal or higher attendance to cervical screening in Sweden in a cohort of opportunistically vaccinated young women. Most but not all of the difference in attendance was explained by socioeconomic differences between vaccinated and unvaccinated women. HPV vaccine effectiveness studies should consider screening attendance of HPV-vaccinated women when assessing incidence of screen-detected cervical lesions.

Change in population prevalences of human papillomavirus after initiation of vaccination: the high-throughput HPV monitoring study.

BACKGROUND: Organized human papillomavirus (HPV) vaccination was introduced in Sweden in 2012. On-demand vaccination was in effect from 2006 to 2011. We followed the HPV prevalences in Southern Sweden from 2008 to 2013. METHODS: Consecutive, anonymized samples from the Chlamydia trachomatis screening were analyzed for HPV DNA for two low-risk types and 14 high-risk types using PCR with genotyping using mass spectrometry. We analyzed 44,146 samples in 2008, 5,224 in 2012, and 5,815 in 2013. RESULTS: Registry-determined HPV vaccination coverages of the population in Southern Sweden increased mainly among 13- to 22-year-old women. Most analyzed samples contained genital swabs from women and the HPV6 prevalence in these samples decreased from 7.0% in 2008 to 4.2% in 2013 [-40.0%; P < 0.0005 (χ(2) test)]. HPV16 decreased from 14.9% to 8.7% (-41.6%; P < 0.0005) and HPV18 decreased from 7.9% to 4.3% (-45.6%; P < 0.0005) among 13- to 22-year-old women. There were only small changes in vaccination coverage among 23- to 40-year-old women. In this age group, HPV18 decreased marginally (-19.6%; P = 0.04) and there were no significant changes for HPV6 or HPV16. Two nonvaccine HPV types (HPV52 and HPV56) were increased among 13- to 22-year-old women, both in 2012 and 2013. CONCLUSIONS: A major reduction of HPV6, 16, and 18 prevalences is seen in the age groups with a concomitant increase in HPV vaccination coverage. The minor changes seen for nonvaccine types will require further investigation. IMPACT: Monitoring of type-specific HPV prevalences may detect early effects of HPV vaccination.

Treatment of hepatitis C virus infection: updated Swedish Consensus recommendations.

In a recent expert meeting, Swedish recommendations for the treatment of HCV infection were upgraded. The panel recommends vaccination against both hepatitis A and B in patients with HCV. Therapy for symptomatic acute HCV infection should be initiated if spontaneous resolution has not occurred within 12 weeks, whereas asymptomatic acute HCV should be treated upon detection. Patients with genotype 2/3 infection should generally be treated for 24 weeks. In patients with a very rapid viral response (vRVR), i.e. HCV RNA below 1000 IU/ml on d 7, treatment can be shortened to 12-16 weeks, provided that no dose reduction has been made. For genotype 1 patients with rapid viral response (RVR), 24 weeks treatment is recommended. For patients with a complete early viral response (cEVR), 48 weeks treatment is recommended, whereas 72 weeks treatment should be considered for patients with partial early viral response (pEVR). For patients with difficult-to-treat disease and with pronounced anaemia, erythropoietin can be used to maintain the ribavirin dose. In HCV-HIV coinfected patients, combination therapy for HCV should, if possible, be initiated before anti-retroviral therapy (ART) is indicated. For liver transplant patients pre-emptive therapy is not recommended; hence, treatment should be deferred until histological recurrence.

Treatment of chronic hepatitis B infection: an update of Swedish recommendations.

The main goal for treatment of chronic hepatitis B is to prevent complications such as liver cirrhosis or hepatocellular carcinoma. Knowledge from population studies of the long-term risk of chronic HBV infection, as well as the recent introduction of pegylated interferon and additional nucleoside analogues has changed the therapeutic situation. Recently, a Swedish expert panel convened to update the national recommendations for treatment. The panel recommends treatment for patients with active HBV infection causing protracted liver inflammation or significant liver fibrosis, verified by liver histology. In general, pegylated interferon alpha-2a is recommended as first-line treatment, in particular for HBeAg-positive patients with HBV genotypes A or B. Among nucleoside analogues, entecavir is the first choice and adefovir or tenofovir can be used as alternatives. Lamivudine monotherapy is not recommended due to the high risk of resistance development. Combinations of nucleoside analogues such as tenofovir and lamivudine or emtricitabine are alternatives for patients with non-response or infection with resistant variants, or as first choice for patients with advanced liver disease. Nucleoside analogue treatment should be monitored to detect primary non-response and virological breakthrough. Special recommendations are given for HBV/HIV coinfected patients, immunosuppressed patients, children, and for treatment before and after liver transplantation. The present guideline is translated from Swedish, where it is published on the MPA and RAV websites (www.mpa.se and www.rav.nu.se) including 7 separate papers based on thorough literature search. The complete reference list can be received from the Medical Products Agency upon request.

A low-dose intradermal hepatitis B vaccine programme in health-care workers and students is highly effective and cost saving: a retrospective follow-up survey in the clinical setting.

OBJECTIVE: To evaluate compliance, serologic response and the cost-benefit of a low-dose intradermal hepatitis B vaccination programme, followed by intramuscular boosters in non-responders. MATERIAL AND METHODS: The study comprised a retrospective survey of 1521 health-care workers and 968 students. Response was defined as hepatitis B antibody titres > or =10 IU/L. Non-response included vaccinees with undetectable antibodies and a hypo-response if antibodies were detectable. RESULTS: Overall, 2145/2489 (86%) subjects completed the intradermal series, whereof 1840/2489 (74%) complied with the serological check-up. Response was achieved in 1517/1840 (82.5%), whereas 107/1840 (5.8%) had a hypo-response and 216/1840 (11.7%) had an undetectable response. In a logistic regression model, younger age (odds ratio 0.73 (95% CI: 0.65-0.82, p<0.001)) and female gender (odds ratio 2.16 (95% CI: 1.67-2.80; p<0.001)) were predictive of response. In hypo-responders and those with undetectable responses, 43/46 (94%) and 71/136 (52%), respectively, had a response after the first intramuscular booster. Hence, in compliant vaccinees an overall seroprotection rate of 94% was reached after a single intramuscular booster. A cost-benefit analysis indicated a cost reduction exceeding 50% compared to a standard intramuscular vaccine regimen. CONCLUSIONS: In the clinical setting, a low-dose intradermal hepatitis B vaccination programme, followed by intramuscular boosters to non-responders, is effective and cost saving.

Antiretroviral treatment of HIV infection: Swedish recommendations 2005.

On 2 earlier occasions, in 2002 and 2003, the Swedish Medical Products Agency (MPA) and the Swedish Reference Group for Antiviral Therapy (RAV) have jointly publicized recommendations for the treatment of HIV infection. A working group from the same expert team that produced the 2002 report has now revised the text again. Since the publication of the last treatment recommendations, 4 new medicines have become available: emtricitabine, atazanavir, fosamprenavir, and enfuvirtid. The last-mentioned belongs to a new class of HIV medications called fusion inhibitors (Box 1). It is likely that tipranavir will also be on the market soon. Simultaneously, the drug zalcitabin has been deregistered. The following updated recommendations parallel the earlier ones, but increased knowledge allows us to be more specific in our recommendations. Thus, it is now suggested that the initial treatment for HIV infection consist of 2 nucleoside reverse transcriptase inhibitors (NRTIs) and 1 non-nucleoside reverse transcriptase inhibitor (NNRTI); or 2 NRTIs and 1 protease inhibitor (PI). In the group of the NRTIs, stavudine is no longer recommended for this purpose. In the NNRTI group, efavirenz should be preferred to nevirapine, except under special circumstances. Finally, PIs ought to be boosted with ritonavir (PI/r). Also new are recommendations regarding treatment choices for patients co-infected with hepatitis B virus (HBV) or tuberculosis (TB). As in the case of the previous publication, recommendations are evidence-graded in accordance with the Oxford Centre for Evidence Based Medicine, 2001 (see http://www.cebm.net/levels_of_evidence.asp#levels), and have been supplemented with references to newly-added sections and data not referred to in earlier background documentation.

[Antiviral agents in influenza--current recommendations. Anti-influenza agents are not a substitution for but a complement to vaccination]. / Antivirala läkemedel vid influensa--aktuella rekommendationer. Influensaläkemedel ersätter inte vaccination men ar ett bra komplement.

This article summarizes a Swedish consensus guidance document on the use of antiviral drugs in the management of influenza. Vaccination remains the cornerstone for influenza prophylaxis. Treatment with neuraminidase inhibitors is recommended for high-risk groups and individuals hospitalised with influenza. Chemoprophylaxis is targeted at high-risk groups and should be considered on a case by case basis depending on the circumstances. Unvaccinated at-risk patients or seasonal vaccine strain mismatch were identified as potential indications for antiviral prophylaxis. Oseltamivir prophylaxis can otherwise be considered for influenza in a household including an at-risk individual and in outbreaks in hospitals and nursing homes. The use of antivirals in a pandemic situation is also discussed.

Serum ALT levels as a surrogate marker for serum HBV DNA levels in HBeAg-negative pregnant women.

In Stockholm, Sweden, the majority of pregnant women positive for hepatitis B surface antigen (HBsAg) are hepatitis Be antigen (HBeAg) negative. Newborns to HBeAg positive mothers receive vaccination and hepatitis B immunoglobulin (HBIg). Newborns to HBeAg negative mothers receive vaccine and HBIg only if the mothers have elevated ALT levels. The aim of this study was to retrospectively evaluate ALT levels as a surrogate marker for HBV DNA levels in HBeAg negative carrier mothers. Altogether 8947 pregnant women were screened for HBV markers from 1999 to 2001 at the Virology Department, Karolinska Hospital. Among mothers screened 192 tested positive for HBsAg (2.2%). 13 of these samples could not be retrieved. Of the remaining 179 sera, 8 (4%) tested positive for HBeAg and 171 (95.5%) were HBeAg negative. Among the HBeAg negative mothers, 9 had HBV DNA levels > 10(5) copies/ml, and of these 7 had normal ALT levels indicating low sensitivity of an elevated ALT level as a surrogate marker for high HBV DNA level. Furthermore, no correlation was found between ALT and HBV DNA levels. Hence, it is concluded that the use of ALT as a surrogate marker for high viral replication in HBeAg negative mothers could be questioned.

Chronic hepatitis C: updated Swedish consensus.

In 1999 a Swedish national expert panel published recommendations for the treatment of chronic hepatitis C (HCV) infection. Recently, pegylated interferon (peg-IFN) products have been introduced, and an increased knowledge concerning treatment of acute HCV and HCV-human immunodeficiency virus (HIV) coinfection has been gained. As a result of this, an update of the Swedish recommendations was developed following an expert meeting in October 2002. The panel now recommends the use of peg-IFN together with ribavirin as the standard treatment. Owing to the excellent response rates in HCV genotype 2 and 3 infections, these patients can be treated for 24 weeks without preceding liver biopsy. For patients with genotype 1 infection (with a slightly below 50% sustained response rate after 48 weeks treatment) and only mild histological disease, treatment can be postponed until future better treatment options become available. In patients who fail to achieve a 99% reduction (2 log drop) in viral titre after 12 weeks of treatment, discontinuation of therapy is recommended. Patients previously treated with IFN monotherapy and not having achieved a sustained virological response are recommended the same combination treatment as treatment-naive patients. IFN monotherapy is recommended in patients with acute hepatitis C. For children with chronic HCV infection, combination treatment is mainly recommended in clinical trials. For HCV-HIV coinfected patients, combination treatment is recommended and preferably given when blood CD4 counts are above 350/ml and before antiretroviral treatment (ART) is needed. Concurrent ART or prominent liver fibrosis requires frequent monitoring because of the increased risk for mitochondrial toxicity and liver failure.

Antiretroviral treatment of human immunodeficiency virus infection: Swedish recommendations.

The Swedish guidelines (SwG) for treatment of human immunodeficiency virus (HIV) infection have several important roles. A major task involves the promotion of a uniformly high standard of care in all HIV treatment clinics in Sweden and the identification of strengths, weaknesses and relevance of recent research findings. CD4+ T-cell counts < 200 cells/microl are clear indications for the initiation of treatment, whereas high viral loads serve as an indication for increased vigilance rather than a criterion for therapy. It is recommended that the first regimen consists of 2 nucleoside reverse transcriptase inhibitors in combination with 1 protease inhibitor or 1 non-nucleoside reverse transcriptase inhibitor. The definition of treatment failure is rigorous. Treatment change should be considered if the viral load has not fallen by at least 1.5 log in 4 weeks or is undetectable within 3-4 months. Resistance testing is endorsed at primary infection, in the event of treatment failure and in pregnant women. Interaction with experts in HIV resistance testing is emphasized. Therapeutic drug monitoring is advocated. Patients with treatment failure should be handled individually and the decision on therapeutic strategy should be based on treatment history, resistance testing and other clinical facts. The SwG do not give recommendations for some important issues such as prolonged drug holidays and preferences in initial treatment regimens. More scientific data are likely to be available soon and the SwG will be refined accordingly. The present guidelines are translated from Swedish; they are published on the Medical Products Agency (MPA) and Swedish Reference Group for Antiviral Therapy (RAV) websites (www.mpa.se and www.rav.nu.se), including 7 separate papers based on a thorough literature search. A complete reference list is available on request from the MPA.