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This paper reviews the English language literature on the safety, immunogenicity and effectiveness in children infected with the human immunodeficiency virus (HIV) of vaccines currently recommended by WHO for use in national immunization programmes. Immunization is generally safe and beneficial for children infected with HIV, although HIV-induced immune suppression reduces the benefit compared with that obtained in HIV-uninfected children. However, serious complications can occur following immunization of severely immunocompromised children with bacillus Calmette-Guérin (BCG) vaccine. The risk of serious complications attributable to yellow fever vaccine in HIV-infected persons has not been determined. WHO guidelines for immunizing children with HIV infection and infants born to HIV-infected women differ only slightly from the general guidelines. BCG and yellow fever vaccines should be withheld from symptomatic HIV-infected children. Only one serious complication (fatal pneumonia) has been attributed to measles vaccine administered to a severely immunocompromised adult. Although two HIV-infected infants have developed vaccine-associated paralytic poliomyelitis, several million infected children have been vaccinated and the evidence does not suggest that there is an increased risk. The benefits of measles and poliovirus vaccines far outweigh the potential risks in HIV-infected children. The policy of administering routine vaccines to all children, regardless of possible HIV exposure, has been very effective in obtaining high immunization coverage and control of preventable diseases. Any changes in this policy would have to be carefully examined for a potential negative impact on disease control programmes in many countries.

Since its widespread introduction, the hepatitis B vaccine has become an essential part of infant immunization programmes globally. The vaccine has been particularly important for countries where the incidence of hepatitis B virus-related hepatocellular carcinoma is high. Effective treatment options for individuals with chronic hepatitis B infection were limited until 1998 when lamivudine, the first nucleoside analogue drug, was introduced. As a single treatment agent, however, lamivudine has a significant drawback: it induces lamivudine-resistant hepatitis B virus strains that may pose a risk to the global hepatitis B immunization programme. Mutations associated with drug treatment can cause changes to the surface antigen protein, the precise part of the virus that the hepatitis B vaccine mimics. However, the emergence of antiviral drug-associated potential vaccine escape mutants (ADAP-VEMs) in treated patients does not necessarily pose a significant, imminent threat to the global hepatitis B immunization programme. Nonetheless, there is already evidence that current treatment regimens have resulted in the selection of stable ADAPVEMs. Treatment is currently intended to prevent the long-term complications of hepatitis B virus infection, with little consideration given to potential adverse public health impacts. To address individual and public health concerns, trials are urgently needed to find the optimal combination of existing drugs that are effective but do not induce the emergence of ADAP-VEMs. This paper examines the mechanism of antiviral drug-selected changes in the portion of the viral genome that also affects the surface antigen, and explores their potential impact on current hepatitis B immunization programmes. Depuis son introduction a grande echelle, le vaccin contre l'hepatite B est devenu une composante essentielle des programmes de vaccination infantile partout dans le monde. Ce vaccin est particulierement important pour les pays ou I'incidence des carcinomes hepatocellulaires lies a une infection par le virus de I'hepatite B (VHB) est elevee. Jusqu'en 1998, date a laquelle est apparue la lamivudine, premier analogue nucleosidique, les options therapeutiques efficaces pour traiter les individus atteints d'hepatite B chronique etaient limitees. En tant qu'agent therapeutique unique, la lamivudine presente cependant un inconvenient notable : elle induit I'apparition de souches de VHB resistantes a la lamivudine qui risqueraient de compromettre les programmes de vaccination contre I'hepatite B a l'echelle mondiale. Les mutations associees au traitement par ce medicament peuvent entrafner des modifications au niveau des proteines antigeniques de surface, c'est-a-dire precisement dans la partie du virus qu'imite le vaccin contre l'hepatite B. Cependant, l'apparition de << mutants d'echappement au vaccin >> potentiellement associes au traitement antiviral (ADAP-VEM), chez les malades traites ne represente pas necessairement une menace importante et imminente pour le programme mondial de vaccination contre I'hepatite B. Neanmoins, il existe deja des preuves de la selection par les schemas therapeutiques actuellement appliques de mutants ADAP-VEM stables. On administre aujourd'hui le traitement pour prevenir les complications a Iong terme d'une infection par le VHB, en accordant peu d'attention a ses impacts negatifs eventuels sur la sante publique. Pour repondre aux preoccupations individuelles et de sante publique, il est urgent de proceder a des essais pour selectionner une combinaison optimale de medicaments existants, qui soit efficace sans induire l'emergence de mutants ADAP-VEM. Le present article etudie le mecanisme regissant les modifications selectionnees par les antiviraux dans la partie du genome virai qui influe aussi sur l'antigene de surface ainsi que l'impact potentiel de ces modifications sur les programmes actueis de vaccination contre l'hepatite B. Desde su introduccion generalizada, la vacuna contra la hepatitis B se ha convertido en un elemento esencial de los programas de inmunizacion de los lactantes en todo el mundo, La vacuna ha sido ademas especialmente util en los paises con alta incidencia de carcinoma hepatocelular relacionado con el virus de la hepatitis B. Las opciones terapeuticas eficaces para las personas con hepatitis B cronica eran limitadas hasta 1998, ano en que se introdujo la lamivudina, el primer analogo nucleosidico. Como tratamiento unico, sin embargo, la lamivudina tiene un inconveniente importante, y es que induce la aparicion de cepas de virus de la hepatitis B resistentes a ese medicamento, fenomeno que puede hacer peligrar el programa mundial de inmunizacion contra la hepatitis B. Las mutaciones asociadas a la farmacoterapia pueden alterar la proteina dei antigeno de superficie, precisamente la parte dei virus mimetizada por la vacuna contra esa hepatitis. Sin embargo, la aparicion de posibles mutantes de escape de la vOEcuna asociados al uso de antivirales (MEV-AUAV) en los pacientes tratados no supone necesariamente una amenaza relevante e inminente para el programa mundial de inmunizacion contra la hepatitis B. Asi y todo, existen ya datos que demuestran que los actuales regimenes terapeuticos han provocado la aparicion de MEV-AUAV. EI tratamiento se orienta actualmente a prevenir las complicaciones a largo plazo de la infeccion que causa el virus de la hepatitis B, sin considerar apenas el impacto potencial en la salud publica. A fin de responder a la inquietud que ello ha suscitado en relacion con la salud individual y la salud publica, es preciso emprender urgentemente ensayos que permitan hallar la combinacion optima de medicamentos ya existentes que sean eficaces pero no induzcan la aparicion de MEV-AUAV. En este articulo se estudia el mecanismo de los cambios provocados por los antivirales en la parte dei genoma virai que afecta tambien al antigeno de superficie, y se analiza el impacto potencial en los actuales programas de inmunizacion contra la hepatitis B., Introduction Since its widespread introduction in 1983, the hepatitis B vaccine has become an essential part of infant immunization programmes globally, and is the key component of the global hepatitis [...]

Aboriginal and Torres Strait Islanders have suffered violence and extreme prejudice in every walk of life as a result of the European colonisation of Australia. We acknowledge the ongoing colonial legacy to this suffering and discuss how cultural safety is a solution to overcoming some elements of the disadvantages that still beset Aboriginal and Torres Strait Islander people in terms of accessing health care. Accessible and culturally safe health services are critical in reducing health inequalities for First Nations' people because of the burden of ill-health they experience. 'Cultural safety' in this context refers to approaches that strengthen and respectfully engage with Aboriginal and Torres Strait Islander cultures in mainstream services. Alongside holistic Indigenous health and primary prevention approaches, a broad range of medical, socio-cultural and allied health support is needed to alleviate these inequalities. In this article, we describe how the working relationship between Aboriginal Hospital Liaison Officers and Social Workers in public hospitals in Victoria, Australia, contributes to cultural safety, and thereby improves the quality of care and a reduction in discharges against medical advice by Aboriginal patients. We conclude that elements of this model may be applicable to improving care for First Nation peoples in other countries. [ABSTRACT FROM AUTHOR]

The Expanded Programme on Immunization (EPI) in Papua New Guinea (PNG) was launched in 1977. Subsequently, it has been extremely difficult to reach every child with all scheduled vaccines for a number of reasons. Even when the reasons have been identified (such as difficult terrain making access difficult), it has proved difficult to overcome these roadblocks. Indeed, the overall vaccine coverage has remained stagnant for over a decade. PNG is not reaching its immunization goals and is one of the poorest-performing countries in the South Pacific. Nonetheless, some provinces are able to achieve high coverage, even in the current environment. One of the reasons seems to be the quality of leadership at provincial and district levels. The emergence of successful public health authorities is a real light at the end of a dark tunnel. Low coverage, particularly relating to polio vaccine and measles-containing vaccine, continues to be a risk for large outbreaks, potentially causing high numbers of death and illness. This risk is not uniform throughout the country, but is especially severe in areas and communities with low coverage. In the 2013 measles outbreak, there may have been as many as 75,000 cases, placing other Pacific island countries at potential risk. Encouragingly, donors are looking to invest large amounts of capital into refurbishing the cold chain. Although funds are not plentiful in PNG and will not be for the foreseeable future, money in itself is not the constraint. The fundamental systems in place to run the health services are not yet running smoothly. Until these are sorted out, more cash will not fix it. [ABSTRACT FROM AUTHOR]

Introduction:Standard measles control strategies include achieving high levels of measles vaccine coverage using routine delivery systems, supplemented by mass immunization campaigns as needed to close population immunity gaps. Areas covered:This review looks at how supplementary immunization activities (SIAs) have contributed to measles control globally, and asks whether such a strategy has a place in Pacific Islands today. Expert commentary:Very high coverage with two doses of measles vaccine seems to be the optimal strategy for controlling measles. By 2015, all but two Pacific Islands had introduced a second dose in the routine schedule; however, a number of countries have not yet reached high coverage with their second dose. The literature and the country reviews reported here suggest that a high coverage SIA combined with one dose of measles vaccine given in the routine system will also do the job. The arguments for and against the use of SIAs are complex, but it is clear that to be effective, SIAs need to be well designed to meet specific needs, must be carried out effectively and safely with very high coverage, and should, when possible, carry with them other public health interventions to make them even more cost-effective. [ABSTRACT FROM PUBLISHER]

There is an ever-expanding technology that is aimed at making the administration of vaccines safer. Conventional ways of administering vaccines are being upgraded, modified or replaced by a wide variety of innovations. The paradigm of liquid vaccines, needles and syringes is slow to change, but already developments are ocurring that will change for ever the way vaccines are administered and will improve the safety record of immunization. The oral route of vaccine administration has generally been thought of as safe, but until now only the polio vaccine has been widely used in this way. The conventional method of vaccine administration is by injection. Many ingenious devices have become available that now make injecting safer. Inventors are now looking imaginatively to alternative routes and technologies for delivering vaccines.Vaccines are genreally manufactured to extremely high standards and rarely are shown to be the cause of safety issues. People remain the weakest safety link is vaccine administration. Technologies that bypasses the ability of man to make bad decisions or to behave incorrectly are of tremendous value. The vaccine world is in the middle of a radical re-think about how vaccines might best be administered. The presentation of the vaccine can be altered to fit new technologies such as powder jet guns, or skin patches. Even the conventional needle and syringe have evolved to much safer versions, and are set to continue this evolution. All this means even safer vaccines and their delivery. [Copyright &y& Elsevier]

While a number of studies remain to be completed, evidence is mounting that there is no demonstrable risk for infants immunized with vaccines containing thiomersal. Epidemiological studies in the US have shown no developmental or other central nervous system abnormalities resulting from exposure to vaccines containing thiomersal. During the initial evaluation of thiomersal in vaccines during 1999, the toxicological profile of ethyl mercury was unknown and presumed to be the same as that of methyl mercury. Enough evidence has accumulated since then to indicate the profiles of the two compounds are different in crucial aspects. To date, one study has measured blood levels of total mercury in vaccinated infants and reports only a brief low-level exposure with rapid excretion of mercury. It is not yet known for sure how much (if any) vaccine-derived ethyl mercury in the blood crosses the blood–brain barrier.For the most part, the use of thiomersal as a vaccine preservative has been convincingly shown to be safe. The scientific evidence is not yet sufficiently strong to provide the same level of assurance for thiomersal-containing vaccines for use in pregnant women or the premature or low birth weight infant. There is an increased sensitivity of the fetal brain to mercury whether it is ethyl or methyl mercury. While there is no evidence to support the contention, it is at least theoretically possible that very low birth weight premature infants may be at increased risk from thiomersal-containing vaccines. Until such time as the scientific evidence is to hand, thiomersal-free presentations of hepatitis B are to be preferred for the birth dose.Given the same levels of exposure, adults are at much lower levels of risk because of increased body mass. It is not possible to prove that thiomersal is completely safe-epidemiology can only quantify a risk, not prove its absence. [Copyright &y& Elsevier]

Abstract: Objective: To measure immunization coverage among children aged 12–23 months in Papua New Guinea (PNG) and to assess if and why there are differences between hard-to-reach and more accessible communities. Methods: WHO cluster sampling methodology was employed to measure immunization coverage in PNG''s four regions. Survey data were re-analyzed according to a local assessment of geographical accessibility indicated by census unit type: urban, rural and hard-to-reach. Census units were designated as hard-to-reach if they were five or more kilometres from a health centre. Findings: Nationwide coverage for most antigens falls below the national target of 80% although there are regional differences with Islands performing the best. Late doses are a major concern: just 4% were fully immunized with valid (“on time”) doses by 1 year of age. Coverage was lower in both rural and remote communities: at 6 months 48% of children from urban units had received three valid doses of DTP-3 but only 16% in rural areas and 13% in hard-to-reach communities. Reasons for failure to immunize varied: 21% of mothers said their child was not immunized because distance, travel conditions or cost of transportation prevented access to local health centres; 27% cited a lack of knowledge or misconceptions about immunization; while 29% believed it was because of an issue with the health system. Conclusions: Throughout PNG there is an urgent need to increase immunization coverage and to ensure that children are immunized on time according to the schedule. Both coverage and timeliness of doses are worse for children living in hard-to-reach and rural areas. Achieving national immunization targets requires improvements in health service delivery, including outreach, especially for remote and rural communities, as well as greater community education and social mobilisation in support of immunization services. [Copyright &y& Elsevier]

There is nothing new about supervision in primary health care service delivery. Supervision was even conducted by the Egyptian pyramid builders. Those supervising have often favoured ridicule and discipline to push individuals and communities to perform their duties. A traditional form of supervision, based on a top-down colonial model, was originally attempted as a tool to improve health service staff performance. This has recently been replaced by a more liberal "supportive supervision". While it is undoubtedly an improvement on the traditional model, we believe that even this version will not succeed to any great extent until there is a better understanding of the human interactions involved in supervision. Tremendous cultural differences exist over the globe regarding the acceptability of this form of management. While it is clear that health services in many countries have benefited from supervision of one sort or another, it is equally clear that in some countries, supervision is not carried out, or when carried out, is done inadequately. In some countries it may be culturally inappropriate, and may even be impossible to carry out supervision at all. We examine this issue with particular reference to immunization and other primary health care services in developing countries. Supported by field observations in Papua New Guinea, we conclude that supervision and its failure should be understood in a social and cultural context, being a far more complex activity than has so far been acknowledged. Social science-based research is needed to enable a third generation of culture-sensitive ideas to be developed that will improve staff performance in the field.

Objective: An in-depth evaluation of rural immunization services in Papua New Guinea was conducted to determine the reasons for poor immunization coverage, as well as to document the impact of recent efforts to strengthen the national immunization program., Method: A qualitative process was used to complement quantitative monitoring data. An interview process, based on open-ended questions, active listening and observation, was designed whereby a team of program supervisors collected information from rural health staff. The teams interviewed health staff in 30 health centres that were selected to provide examples of contrasting field situations., Results: This qualitative review provided valuable detail about why immunization services were failing, encompassing locally specific weaknesses, such as logistic reasons for not conducting outreach, and generic systemic problems such as lack of access to funding. In addition, the information gathered provided details on local solutions developed by better-performing facilities. Both these aspects added significant value to quantitative measures of program performance (derived from national health information system data and analysis of supervision checklists). The review also captured a number of behavioural reasons that will need to be overcome before an improvement in the services can be expected., Conclusions and Implications: This in-depth evaluation provided valuable information about problems in peripheral immunization clinics and identified local solutions. The high level of detail collected will be important for planning future strengthening of the health system. The study modelled a supportive form of supervision with the potential to improve outcomes from future supervisory visits. Some of the major barriers to improved immunization were locally specific organizational issues, as well as complex human problems. While some issues can be remedied through further strengthening of immunization systems, others lack easy, rapid solutions.