World Health Organization Position Research Articles

Zika Virus Infection as a Cause of Congenital Brain Abnormalities and Guillain-Barré Syndrome: Systematic Review.

BackgroundThe World Health Organization (WHO) stated in March 2016 that there was scientific consensus that the mosquito-borne Zika virus was a cause of the neurological disorder Guillain–Barré syndrome (GBS) and of microcephaly and other congenital brain abnormalities based on rapid evidence assessments. Decisions about causality require systematic assessment to guide public health actions. The objectives of this study were to update and reassess the evidence for causality through a rapid and systematic review about links between Zika virus infection and (a) congenital brain abnormalities, including microcephaly, in the foetuses and offspring of pregnant women and (b) GBS in any population, and to describe the process and outcomes of an expert assessment of the evidence about causality.Methods and FindingsThe study had three linked components. First, in February 2016, we developed a causality framework that defined questions about the relationship between Zika virus infection and each of the two clinical outcomes in ten dimensions: temporality, biological plausibility, strength of association, alternative explanations, cessation, dose–response relationship, animal experiments, analogy, specificity, and consistency. Second, we did a systematic review (protocol number CRD42016036693). We searched multiple online sources up to May 30, 2016 to find studies that directly addressed either outcome and any causality dimension, used methods to expedite study selection, data extraction, and quality assessment, and summarised evidence descriptively. Third, WHO convened a multidisciplinary panel of experts who assessed the review findings and reached consensus statements to update the WHO position on causality. We found 1,091 unique items up to May 30, 2016. For congenital brain abnormalities, including microcephaly, we included 72 items; for eight of ten causality dimensions (all except dose–response relationship and specificity), we found that more than half the relevant studies supported a causal association with Zika virus infection. For GBS, we included 36 items, of which more than half the relevant studies supported a causal association in seven of ten dimensions (all except dose–response relationship, specificity, and animal experimental evidence). Articles identified nonsystematically from May 30 to July 29, 2016 strengthened the review findings. The expert panel concluded that (a) the most likely explanation of available evidence from outbreaks of Zika virus infection and clusters of microcephaly is that Zika virus infection during pregnancy is a cause of congenital brain abnormalities including microcephaly, and (b) the most likely explanation of available evidence from outbreaks of Zika virus infection and GBS is that Zika virus infection is a trigger of GBS. The expert panel recognised that Zika virus alone may not be sufficient to cause either congenital brain abnormalities or GBS but agreed that the evidence was sufficient to recommend increased public health measures. Weaknesses are the limited assessment of the role of dengue virus and other possible cofactors, the small number of comparative epidemiological studies, and the difficulty in keeping the review up to date with the pace of publication of new research.ConclusionsRapid and systematic reviews with frequent updating and open dissemination are now needed both for appraisal of the evidence about Zika virus infection and for the next public health threats that will emerge. This systematic review found sufficient evidence to say that Zika virus is a cause of congenital abnormalities and is a trigger of GBS.

An uncertain risk: the World Health Organization's account of H1N1.

Scientific uncertainty is fundamental to the management of contemporary global risks. In 2009, the World Health Organization (WHO) declared the start of the H1N1 Influenza Pandemic. This declaration signified the risk posed by the spread of the H1N1 virus, and in turn precipitated a range of actions by global public health actors. This article analyzes the WHO's public representation of risk and examines the centrality of scientific uncertainty in the case of H1N1. It argues that the WHO's risk narrative reflected the context of scientific uncertainty in which it was working. The WHO argued that it was attempting to remain faithful to the scientific evidence, and the uncertain nature of the threat. However, as a result, the WHO's public risk narrative was neither consistent nor socially robust, leading to the eventual contestation of the WHO's position by other global public health actors, most notably the Council of Europe. This illustrates both the significance of scientific uncertainty in the investigation of risk, and the difficulty for risk managing institutions in effectively acting in the face of this uncertainty.

Worldwide variation in human growth and the World Health Organization growth standards: a systematic review

ObjectiveThe World Health Organization (WHO) has established a set of growth curves for use as international standards in children up to age 5. The WHO's position is that all economically...

Yellow fever vaccination: Is one dose always enough?

In March 2013, the World Health Organization (WHO) Strategic Advisory Group of Experts on Immunisation (SAGE) considered a number of issues in order to update the WHO Position Paper on Yellow Fever (2003). A key conclusion of this review was that a single dose of yellow fever (YF) vaccine appears to confer life-long protection against YF disease, and that a booster dose of YF vaccine is not needed to maintain immunity. While the efficacy of YF vaccine in the majority of vaccine recipients is not in doubt, the WHO announcement is somewhat surprising as there are some limitations in the evidence base, but more importantly, this announcement is not accompanied by any imminent change in the International Health Regulations 2005. The tension between what is considered best clinical practice and the law will be difficult to reconcile for many health professionals, travellers, and the travel industry, in an area of travel medicine that is already subject to debate and confusion. This commentary reviews the recent WHO announcement, and considers the practical implications for health professionals providing YF vaccine to international travellers.

Seasonal influenza vaccine policies, recommendations and use in the World Health Organization's Western Pacific Region.

Vaccination is the most effective way to prevent seasonal influenza and its severe outcomes. The objective of our study was to synthesize information on seasonal influenza vaccination policies, recommendations and practices in place in 2011 for all countries and areas in the Western Pacific Region of the World Health Organization (WHO). Data were collected via a questionnaire on seasonal influenza vaccination policies, recommendations and practices in place in 2011. Thirty-six of the 37 countries and areas (97%) responded to the survey. Eighteen (50%) reported having established seasonal influenza vaccination policies, an additional seven (19%) reported having recommendations for risk groups for seasonal influenza vaccination only and 11 (30%) reported having no policies or recommendations in place. Of the 25 countries and areas with policies or recommendations, health-care workers and the elderly were most frequently recommended for vaccination; 24 (96%) countries and areas recommended vaccinating these groups, followed by pregnant women (19 [76%]), people with chronic illness (18 [72%]) and children (15 [60%]). Twenty-six (72%) countries and areas reported having seasonal influenza vaccines available through public funding, private market purchase or both. Most of these countries and areas purchased only enough vaccine to cover 25% or less of their populations. In light of the new WHO position paper on influenza vaccines published in 2012 and the increasing availability of country-specific data, countries and areas should consider reviewing or developing their seasonal influenza vaccination policies to reduce morbidity and mortality associated with annual epidemics and as part of ongoing efforts for pandemic preparedness.

Inhalant Horse Allergens and Allergies: A Review of the Literature

A wealth of literature exists regarding common allergies to household pets such as cat or dog. Allergy to horse, however, is infrequently discussed in the medical literature despite significant sensitization rates among urban-dwelling subjects without direct exposure to horses. A literature search was conducted in PubMed and additional references were collected from surveying the references of the pulled articles. This review summarizes aspects of IgE-mediated horse allergy including the prevalence and mechanisms for sensitization, clinical presentation, molecular characterization of the major and minor horse allergens, and the role of allergen immunotherapy. There is currently only one horse immunotherapy study showing significant improvement in clinically sensitive patients. The 1997 World Health Organization Position Paper on Immunotherapy lists horse immunotherapy among the areas needing further clinical research. Inclusion of horse into the standard allergen panel for children and adults has been supported by several authors, although further identification and characterization of horse antigens is needed to provide the most efficacious extract. As clinicians, we need to be aware of the potential cross-reactivity among the common mammalian allergens and consider the possibility of known or occult exposure to horse as a possible source of symptom exacerbation in susceptible individuals.

The gratuitous form of acceptance as the pathway to the resolution of substance abuse (Acceptance)

PurposeThe purpose of this paper is to present the second of two articles about substance abuse and the discussion of acceptance as a two‐pronged description of human thinking, with the primary care physician the intended audience.Design/methodology/approachThe paper is about the presumption of acceptance as an enabler of the learned addiction‐oriented life style.FindingsAccording to the World Health Organization (WHO)'s Global Status Report, there are about 2 billion people consuming alcoholic beverages worldwide, with about 76.3 million diagnosed as having alcohol use disorders.Research limitations/implicationsThe approach in the article differs from that taken in the discussion of relapse, where substance abuse is presented as a subset of addictive‐oriented thinking with respect to a defined group of persons. Here, there are two parallel tracks, with neither limited to any definable subgroup of a population. The first is a continuation of the focus on substance abuse as a subset of addictive‐oriented thinking. The second, however, has addictive‐oriented thinking as the superset of the learned addiction‐oriented life style.Social implicationsThe potential pool of need in the paper is the 2 billion people as the superset of addiction‐oriented living, on this view of relapse and acceptance as the “why” of substance abuse, as a subset of addictive‐oriented thinking.Originality/valueWhile the paper is in line with the WHO's position that substance abuse is the most serious health problem globally, the advocated approach to the resolution of addiction is the efficiency of the relationship between the primary care physician and the patient.

Specific Immunotherapy in a Pollen-Allergic Patient With Human Immunodeficiency Virus Infection

Background According to the World Health Organization position paper, immunodeficiency such as human immunodeficiency virus (HIV) infection is a relative contraindication for specific immunotherapy (SIT). Since the introduction of highly active antiretroviral therapy, a significant reconstitution of immune competence in individuals with HIV is possible.Case Report In a 52-year-old man, HIV infection was diagnosed in 1987. Antiretroviral therapy was started in 1998. He presented himself in July 2001 because of an increasingly severe seasonal rhinoconjunctivitis. Symptoms were not sufficiently alleviated by various antiallergic drugs.Results The investigations showed a relevant sensitization to tree pollens. Specific immunotherapy with a tree pollen mix (hazel, birch, ash, and alder, 25% each) was started in November 2001. Viral load at this time was less than 50 copies/mL, the CD4+ cell count was 307/μL. Therapy was given in monthly intervals until mid-April 2005 without any side effects. Viral load and CD4+ cell counts did not change during SIT. Clinically, rhinoconjunctivitis was experienced only intermittently and symptom relief was almost 90%.Conclusions This report indicates that in patients with well-controlled HIV infection on highly active antiretroviral therapy, SIT with pollen extracts is a potential and successful therapeutic option.

Pertussis vaccine recommendations in the era of acellular vaccines

The development of pertussis vaccines and the resulting decrease in pertussis burden is one of the great public health successes of the last century. Since the introduction of whole-cell vaccines in the 1950s, pertussis has been reduced dramatically in most developed countries and to a lesser degree in many developing countries. The introduction of acellular vaccines in the 1990s has further consolidated this success by reducing the reactogenicity of the vaccine and thus improving its acceptability. However, the success of pertussis vaccination is not as complete as that of other vaccines with which it is often coadministered, such as diphtheria and tetanus. Whereas diphtheria and tetanus have become extremely rare in most developed countries, pertussis has been found to be on the rise again. Typically a disease of young children, pertussis is now seen mostly among adolescents, adults and most importantly, small infants. No vaccine has yet been developed for neonates but two vaccine manufacturers (GlaxoSmithKline and Sanofi-Pasteur) have developed pertussis vaccines that can be administered to adolescents and/or adults. Such vaccines have already been licensed in several countries worldwide and are currently being reviewed by the US Food and Drug Administraion for licensure in the USA. The World Health Organization regularly issues position papers on vaccines and has just published its latest regarding pertussis vaccines. In light of the latest vaccine developments, this position paper is very timely. This article discusses the latest World Health Organization position and its potential implications for health policy makers worldwide.

Rubella and congenital rubella syndrome: global update.

Worldwide, it is estimated that there are more than 100.000 infants born with congenital rubella syndrome (CRS) each year. In 1998, standard case definitions for surveillance of CRS and rubella were developed by the World Health Organization (WHO). In 2001, 123 countries/territories reported a total of 836.356 rubella cases. In the future more countries are expected to report on rubella as a global measles/rubella laboratory network is further developed under the coordination of WHO. Operational research is being conducted to improve rubella surveillance. This includes projects on initiating CRS surveillance, comparative studies on diagnostic laboratory methods, and molecular epidemiology research to expand the global understanding of patterns of rubella virus circulation. In 1996 a WHO survey found that 78 od 214 reporting countries/territories (36%) were using rubella vaccine in their routine immunization services. By the en of 2002 a total of 124 of the 214 counties/territories (58%) were using rubella vaccine. Rubella vaccine use varies by stage of economic development: 100% for industrialized countries, 71% for countries with economies in transition, and 48% for developing countries. A safe effective rubella vaccine is available, and there are proven vaccination strategies for preventing rubella and CRS. A WHO position paper provides guidance on programmatic aspects of rubella vaccine introduction. The introduction of rubella vaccine is cost-effective and cost-beneficial but requires ongoing strengthening of routine immunization services and surveillance systems.

Local reactions during allergen immunotherapy do not require dose adjustment

Background: The recent World Health Organization position paper on allergen immunotherapy states that local reactions to immunotherapy are not predictive of subsequent systemic reactions. Nevertheless, in clinical practice dose adjustment after local reactions continues to be recommended, presumably in an effort to prevent future systemic reactions. Objective: We sought to determine whether dose adjustment versus no adjustment for local reactions during allergen immunotherapy influences the occurrence of subsequent systemic reactions. Methods: In a single-site allergy clinic before October 1, 1997, local reactions after allergen vaccine injection resulted in adjustment of the subsequent dose. After October 1, 1997, no dose adjustments were made for immediate and late local reactions. For the same 9-month period before and after the change in local reaction dose-adjustment policy, systemic reaction rates were compared retrospectively. For individuals experiencing a systemic reaction, local reaction rates and local reactions immediately preceding a systemic reaction were also compared before and after the policy change. Results: Comparing the 9-month period (October 1996-June 1997) preceding the policy change and the 9 months (October 1997-June 1998) after the change in policy, the systemic reaction rates (0.80% and 1.01%, respectively) were not statistically different (P = .24). Among those experiencing a systemic reaction, the rate of local reactions was unchanged (7.3% and 4.7%, respectively; P = .07), and the rate of local reactions immediately preceding a systemic reaction did not increase (18.8% and 10.5%, respectively; P = .37). The sensitivity of a local reaction predicting a systemic reaction at the next immunotherapy dose was 15%. Conclusions: A local reaction is a very insensitive predictor for a subsequent systemic reaction at the next allergen vaccine dose. Dose adjustment for most local reactions is unnecessary and may delay therapy, increase costs, and put the patient at increased risk of dose administration errors. (J Allergy Clin Immunol 2000;106:840-3.)

Double-blind placebo-controlled evaluation of sublingual-swallow immunotherapy with standardized Parietaria judaica extract in children with allergic rhinoconjunctivitis

Background: Sublingual-swallow immunotherapy was recently recognized in the World Health Organization Position Paper (Allergen immunotherapy: therapeutic vaccines for allergic diseases) “as a viable alternative to parenteral injection therapy to treat allergic diseases” in adults. More controlled studies were required to assess the efficacy and safety of this treatment in children. Objective: This study was carried out to assess the clinical efficacy and safety profile of sublingual-swallow immunotherapy with high-dose allergen in children with allergies. Methods: We used a double-blind placebo-controlled design. Forty-one children with Parietaria -induced rhinoconjunctivitis were randomized to receive sublingual standardized Parietaria judaica extract (n = 20) or placebo (n = 21) for 2 years. The cumulative dose of allergen was 375 times higher than that used in parenteral immunotherapy and the cumulative dose of Par j 1 major allergen was 52.5 mg over 2 years. The main efficacy assessment criteria were symptoms and rescue medication scores recorded on the patients’ diary cards. Secondary criteria were changes in skin and conjunctival specific reactivity as well as blood parameters, analyzed after 1 and 2 years of immunotherapy. The safety of the treatment was assessed by evaluating the frequency and severity of adverse effects. Results: A significant reduction in rhinitis symptoms was observed in the active treatment group during the second season ( P = .02), with no difference in medication scores. A significant decrease in skin reactivity ( P = .002 after 2 years of treatment) and an increase in the threshold dose for conjunctival allergen provocation test ( P = .02) were observed in the active treatment group compared with the group receiving placebo. A significant increase in specific IgG 4 levels ( P = .02) was also observed in the active group. Immunotherapy was well tolerated. Conclusion: Sublingual-swallow immunotherapy in Parietaria -allergic children provided a clinical benefit and a decreased specific reactivity to the allergen. The safety profile of this treatment, which constitutes an important issue, indicated good tolerance and compliance. (J Allergy Clin Immunol 1999;104:425-32.)