Safe injection practices in a primary health care setting in Oman.

We conducted a national survey of injection practices in 78 government health facilities in Oman in 2001. Data were obtained by interview and observation. The overall standards were good and the stock of disposable equipment was adequate. Recapping of needles was only observed in 1 facility but in 28%, waste disposal boxes contained recapped needles and 17.9% reported needle-stick injuries in the past year. In 9% of the institutions, sharps were observed around the facility, in 12.8% unsupervised disposal containers were seen and in 11.5% unsafe storage of full boxes was observed. While disposal of the used waste was done away from the health facility, only 33.3% disposed of it by correct incineration.

How best to estimate the global burden of pertussis?

In most countries, pertussis surveillance is inadequate for accurately estimating numbers of cases or deaths. Good estimates are needed to help set priorities for vaccination programmes. We aimed to develop a simple, reliable, and explicit method for estimating pertussis cases and deaths for children under 15 years to calculate the global disease burden in 1999. We estimated the proportion of susceptible children becoming infected in countries with poor vaccination coverage (<70%) in 1999 at 30% by 1 year, 80% by 5 years, and 100% by 15 years of age and for countries with good coverage (> or =70%) at 10% by 1 year, 60% by 5 years, and 100% by 15 years. Vaccine efficacy was estimated at 80% for preventing infection and 95% for preventing deaths. We used UN population estimates and vaccination coverage reported to WHO (adjusted for specific survey data if available). Case fatality ratios for countries with high and low child mortality were derived from published and unpublished work. For some countries with good vital events registration we used reported deaths adjusted for underascertainment. In 1999 there were an estimated 48.5 million pertussis cases in children worldwide. Deaths from pertussis were estimated at 390000 and at 295000 after adjustment for local data sources. Based on this approach, disability-adjusted life years from pertussis (12.7 million) in 2000 exceeded those of other preventable diseases such as lung cancer (11.4 million) and meningitis (5.8 million). This simple approach yields estimates that can be used for setting vaccination programme priorities. Better data are needed on the public health importance of pertussis in high mortality countries, the benefits of incomplete vaccination, and the harm from delayed vaccination.

The Immunization Monitoring Program Active (IMPACT) prospective five year study of Canadian children hospitalized for chickenpox or an associated complication.

BACKGROUND: Varicella vaccine was approved for use in Canada in 1998. A major goal of universal varicella vaccine programs is to reduce severe infection and associated complications. Baseline data are essential against which to judge the effectiveness of routine childhood immunization. OBJECTIVE: To describe morbidity and mortality among children hospitalized for chickenpox. Methods. From January 1, 1991, to March 31, 1996, chickenpox admissions to 11 pediatric referral centers were actively identified. Patient and illness characteristics were compared for 3 subgroups defined by prior health: healthy; unhealthy but immunocompetent; immunocompromised. RESULTS: Of 861 cases 488 (56.7%) were healthy, 75(8.7%) were unhealthy and 298 (34.6%) were immunocompromised. The immunocompromised children differed from healthy/unhealthy cases in mean age (6.4 vs. 4.0/4.6 years, respectively, P < 0.0001); median interval from rash onset to admission (2 vs. 5/5 days, P < 0.0001); complication rate (20% vs. 90%/79%; P = 0.001); and rate of acyclovir therapy (98% vs. 24%/39%; P = 0.001). Unhealthy vs. healthy cases had a higher frequency (P < 0.01) of intensive care (13.3% vs. 4.7%), ventilation (9.3% vs. 2.0%) and death (4% vs. 0.2%). CONCLUSION: These data provide a baseline for morbidity/mortality resulting from chickenpox before varicella vaccine use in Canada.

Injuries and risk factors for injuries from the 29 May 1982 tornado, Marion, Illinois.

On 29 May 1982, a tornado struck Marion, Illinois. As a result, ten people were killed, 38 were hospitalized, and 196 were examined in hospital emergency rooms. In order to describe injuries and to identify risk factors that might have increased or reduced the risk of injuries, we (1) conducted a telephone survey of all persons we could identify who were in the path of the tornado and (2) reviewed the emergency room logs and records and admission files of hospitals that provided initial care. Overall, 19.3% of people who were in the path of the tornado were injured during the impact. Only 39.0% of people examined in emergency rooms were injured as a direct result of the impact. The remainder were injured while rescuing, cleaning up, or just walking in the disaster area. Behaviours that were most protective were being in a house on the lowest floor, staying underground in a basement, protecting one's body with something like a blanket, and staying away from windows. Neither lying down nor opening doors or windows seemed to decrease the risk of being injured. Our results emphasize the need for early warnings and public education about protective behaviours.

An epidemiological description of lightning-related deaths in the United States.

To better quantify and update the health impact of lightning and to compare potential sources of information, we reviewed data from the National Centre for Health Statistics (NCHS) database for 1968 through 1985 and from the North Carolina Medical Examiner (NCME) computerized database for 1972 through 1984. We epidemiologically characterized all lightning-related deaths identified in these databases. Results of our analysis are presented together with previously published information from the National Oceanic and Atmospheric Administration and from the National Institute for Occupational Safety and Health. In the US, Wyoming has the highest average annual lightning-related death rate (0.196/100,000), whereas Florida has the largest cumulative incidence of deaths (200) for this 18-year period. Death rates are the highest for males and for people 10-19 years old. There is a tendency toward a slight, but steady, decrease in the yearly incidence of lightning-related deaths. One-third of the fatalities are job-related. Both the NCHS and NCME databases are limited in describing the circumstances and aetiologies of these deaths.

Skin test reactions to a phenol-soluble antigen of Brucella abortus among veterinary students, Lyon, France, 1984.

In December 1984, 424 students at the National Veterinary College, Lyon, France, were skin-tested with a phenol-soluble antigen of Brucella abortus B19. Of all students, 2.6% had a positive intradermal reaction indicating previous contact with Brucella. Prevalence of positive reactions was significantly lower among students from the three first school years (less than 2%) compared with students in their last school year (5.9%). These results are discussed and compared to the prevalence of brucellosis among cattle. Specificity (94%) of the intradermal testing resembles that of serological testing but its sensitivity (75%) seems to be better.

Measles in adults in Canada and the United States: implications for measles elimination and eradication.

BACKGROUND: Despite the implementation of mass school catch-up campaigns for measles in Canada, an outbreak of measles occurred in early 1997 mostly affecting the adult population. The higher incidence in Canada in adults led us to compare immunization policies and the evolution of measles among adults in Canada and the US. METHODS: Based on information gathered from both national immunization programmes and surveillance systems. RESULTS: Although the proportion of cases occurring in adults has increased tremendously in both countries in the past decade, there was no increase in measles incidence in these populations. The most likely factors to explain the higher rate of measles occurring in adults in Canada are the younger age at administration of first dose in Canada, the delay in implementation of a second dose policy in Canada compared with the US combined with the lack of prematriculation immunization requirements in Canadian colleges and universities, and the higher rate of overseas travel to and from Canada. The situation in Canada may also have been exacerbated by incomplete efforts to control measles for many years without attempting to eliminate the disease. CONCLUSIONS: In order to prevent measles in adults, high-risk groups must be identified and catch-up for selected groups considered. Vaccination of international travellers to endemic areas should be recommended until global elimination has been achieved. Appropriate measles control strategies in younger populations seem to be effective in preventing measles in adults. The experience in Canada and the US suggests that measles transmission in adults is unlikely to be a major impediment to regional elimination or global eradication.

Immunisation safety: a priority of the World Health Organization's Department of Vaccines and Biologicals.

In 1999, the World Health Organization (WHO) Department of Vaccines and Biologicals launched the Immunisation Safety Priority Project to boost its activities in this area, with the aim of establishing a comprehensive system to ensure the safety of all immunisations given in national immunisation programmes. Countries are the primary focus of this project. The WHO has a role to play not only because of its technical and normative role but also because of its privileged relationship with country authorities and other partners, its global vision and mandate, and because it is perceived as free from conflicts of interest. There are four areas of focus in the project: quality control and assessment tools to ensure vaccine safety from clinical trials up to and including the point of use;research and development of safer and simpler delivery systems; access to safer and more efficient systems for vaccine delivery and sharps waste management; and mechanisms to respond promptly and effectively to vaccine safety concerns. The project emphasises the importance of advocating safety and developing necessary infrastructure and human resource to properly deal with immunisation related safety issues at a national level.

Current thoughts on the risks and benefits of immunisation.

Despite a continuous search for safer and more immunogenic vaccines, adverse reactions still occur. Adverse reactions to vaccines are generally mild; severe events resulting in death or permanent damage are rare. In every instance, the benefits of preventing the disease far outweigh the risks of vaccination. In the early days of vaccine development, a number of accidents were associated with faulty production. Most recent problems encountered with the use of vaccines are due to programmatic errors. Because of the large number of doses administered it is probable that there will be some temporal and merely coincidental association between adverse events and vaccine administration. Immunisation has a direct protective effect for the individual and an indirect effect on herd immunity for the community. The major goal of postmarketing surveillance is the early detection of and appropriate response to adverse events in order to curtail a negative impact on immunisation programmes. Risk-benefit analyses for immunisation are faced with a number of potential difficulties; definition of the risks and benefits themselves, individual versus community risks and benefits, and the continuously evolving nature of risks with changes in disease epidemiology. Based on risk-benefit studies, for an individual just as for the community, it may not always be of interest to use the vaccine with the lowest complication rate. Good immunisation programmes should help to decrease the risk of adverse effects.

Measles vaccines: a review of adverse events.

A great deal of controversy has recently been generated over the publication of several articles implicating measles vaccine in the induction of Crohn's disease and autism. The publication of this work has already had a negative impact on measles vaccine acceptance in the UK. These allegations are particularly troubling because they arise in the context of increased use of measles vaccine as global control of measles nears and the international community considers strategies for a drive towards eradication. In 1994, the US Institute of Medicine reviewed the world literature and published a comprehensive review of adverse events associated with measles-containing vaccines. Reviewing the literature published between 1994 and the present day, reveals that there is considerable new data suggesting that modified gelatin rather than egg proteins is responsible for most episodes of anaphylaxis following measles vaccination. New work weakens the possible links between measles vaccine and subacute sclerosing panencephalitis and Guillain-Barré syndrome, but strengthens the rare association of measles-containing vaccines with post infectious encephalomyelitis. The alleged associations between measles vaccination and Crohn's disease and autism are based upon weak science and have largely been refuted by a large volume of stronger work. A review of the data generated in the last 4 years amply demonstrates the continued efforts of the scientific community to monitor and understand true measles vaccine-associated adverse events. The rapidity and clarity of this same community's debunking of the spurious associations with Crohn's disease and autism suggests that those charged with vaccination programmes have learned from past mistakes. During 30 years of worldwide use, measles vaccination has proven to be one of the safest and most successful health interventions in the history of mankind. It is not a 'perfect' vaccine, but the benefits of measles vaccination far outweigh the risks even in countries with low incidence of measles and high rates of measles vaccine coverage.

Isolation and plaque purification of a syncytial forming component of myxoma virus.

Using the endpoint dilution and plaque purification technique performed on rabbit kidney cells, two stable syncytial clones of myxoma virus have been isolated. No eosinophilic intracytoplasmic inclusion bodies nor intranuclear granulations could be detected in cells infected with these clones. Traditional plaques with the central area of detached cells surrounded by round cells also could not be recognized. However, when enough virus was added, one large complete syncytium developed in 24 on the monolayer. Syncytial activity was associated with the entire particle. This was the first time that myxoma virus is reported to demonstrate such an intense syncytial activity.

Carbon source assimilation and fermentation tests: study of 77 animal Pasteurella strains by a microtechnique.

77 strains of Pasteurella from various animal species were tested using the API micromethod for their ability to assimilate 147 carbon substrates and ferment 49 carbohydrates. Typical profiles of P. multocida and P. haemolytica were determined. This micromethod should prove useful in establishing the biotypes of Pasteurella species and in studying their epidemiology and pathogenicity.

Manufacturing processes at two French rapeseed oil companies: possible relationships to toxic oil syndrome in Spain.

The toxic oil syndrome (TOS) epidemic that occurred in Spain in spring 1981 has been associated with the consumption of rapeseed oil that was denatured with aniline for industrial use but diverted for human consumption. The precise aetiologic agent in the oil responsible for the outbreak has not been identified. To learn more about possible contaminants and how the contamination might have occurred, we visited two French companies that process rapeseed oil and that were identified in Spanish administrative and judicial records as the ones exporting aniline-denatured rapeseed oil to Spain in 1981. With the apparently full and voluntary co-operation of personnel at both companies, we reviewed the processes involved in manufacturing, treating and transporting rapeseed oil, and we have summarized the information provided to us. Of particular importance is the finding that oil exported to Spain was taken from stock, the rest of which was sold for human consumption in the French domestic market, apparently without any adverse health effects. The differences between the oil exported to Spain and the oil sold as food in France were that aniline equivalent to 2% of the weight of the oil was added to most of the Spanish oil but not to that sold in France, and that contamination of the Spanish oil may have occurred in the tank trucks used for transportation to Spain, which had previously carried industrial chemicals. There is no assurance that the trucks were cleaned appropriately for transporting a food product before the oil was loaded for the journey to Spain. Since the clinical manifestations of TOS are not those of aniline toxicity, we conclude that the aetiological agent of TOS is likely to be one of the following: (1) a contaminant in the aniline, (2) a contaminant introduced during transportation, (3) a reaction product of normal oil components or materials used in refining with either aniline or the potential contaminants mentioned under (1) or (2) above.

Lightning-related mortality and morbidity in Florida.

Cases of lightning-related deaths and injuries that occurred in Florida in 1978-87 were reviewed to determine the factors involved, to quantify the morbidity and mortality related to lightning strikes, and to describe epidemiologically the injuries and circumstances involved. Statewide information on deaths was obtained from death certificates, autopsy reports, and investigative reports. Information about morbidity was obtained from the Florida Hospital Cost Containment Board data base and the National Climatic Data Center data base for all Florida counties, as well as from hospitals in selected counties. Lightning-related deaths totaled 101 in Florida during the period 1978-87, an annual average of 10.1. Eight percent of the victims were from other States. The overall yearly death rate for State residents was 0.09 per 100,000 population, with the highest rate being that for men aged 15-19 years, 0.38 per 100,000. Thirteen percent of victims were females. The ratio of lightning-related injuries to deaths in Florida was estimated at about four to one. Thirty percent of all deaths were occupationally related. The first strikes of lightning from a thunderstorm may be the most dangerous, not in terms of impact, but because of the element of surprise. During thunderstorms, people may seek shelter under isolated trees because they believe erroneously that a tree offers protection from lightning, or perhaps because their top priority is to escape from rain rather than lightning. People may not seek adequate shelter during thunderstorms because they do not know the dangers of remaining outdoors or their judgment is impaired by drugs or alcohol.

Epidemiology of influenza vaccination in Canada.

To assess influenza vaccine coverage among Canadian adults, questions about the fall/winter 1990-91 immunization campaign were added to the Statistics Canada 1991 General Social Survey. A total of 11,924 usable responses were obtained (response rate 80%). Overall, an estimated 13.8% (95% CI 13.1-14.5) of the Canadian population surveyed and 44.8% (95% CI 42.7-46.9) of the population 65 years of age and over received a "flu" shot during the fall/winter 1990-91 immunization campaign. A logistic regression model run separately in populations less than 65 years of age and in populations 65 and over reveals that, by far, the major predictor for receiving influenza vaccine was a recommendation by a nurse or physician. Two major reasons listed by persons 65 and over for not receiving the flu vaccine were 1) the belief they hardly ever get the flu (39%), and 2) they fear side effects (22%).

Evaluation of the promotional materials used during the measles mass immunization campaign in Ontario and British Columbia.

OBJECTIVE: To evaluate the promotional materials used during measles mass immunization campaign. DESIGN: A telephone survey was conducted among parents of targeted children in Ontario and British Columbia (BC). RESULTS: The leaflet distributed at school was considered to be the most useful source of information for 79% and 69% of the parents of school-aged children in Ontario and BC, respectively. Newspaper articles (27%) and information obtained through public health nurses (24%) were the most appreciated sources of information for the parents of preschoolers only. There was a notable increase in the proportion of parents who considered measles immunization important as well as those who had concerns about measles immunization at the time of the interview compared with the period before the mass campaign. CONCLUSION: The leaflet distributed at school (for parents of school-aged children) and newspaper articles and information obtained from public health nurses (for the parents of preschoolers only) were found to be the most useful sources of information.

Seroprevalence of measles- and rubella-specific antibodies among military recruits, Canada, 1991.

A study of the seroprevalence of measles- and rubella-specific antibodies among military recruits in Canada in 1991 was undertaken to: 1) determine the proportion of military recruits who are measles and/or rubella seropositive when they enter the military; 2) detect general problems in the immune coverage in the young adult population; and 3) determine the proportion of measles seronegativity attributable to non-response, waning immunity or lack of exposure to either the disease or the vaccine. One initial blood sample was collected from all 399 recruits enrolled in basic training during the month of January 1991, prior to immunization with measles-mumps-rubella vaccine (MMR). Another sample was obtained from 354 of these recruits 3 to 5 weeks following this immunization. Only 18 (4.5%) recruits had negative measles-specific neutralization on the first sample. Only 12 (3.0%) recruits had negative measles-specific EIA on the first sample. All recruits had neutralization titres 40 or higher on the second sample. A total of 43 (10.8%) individuals had negative results for rubella EIA before immunization, 35 of which (81.4%) tested positive on the second sample.

[Postmarketing surveillance of secondary effects of vaccines]. / La surveillance des effets secondaires des vaccins après leur commercialisation.

Despite a continuous search for safer and more efficacious vaccines, adverse events continue to occur following vaccine administration. Adverse events are usually mild. Serious adverse events that could result in death or permanent sequelae are extremely rare. In all cases, benefits associated with immunization greatly outweigh the risks. Due to the large number of doses administered, it is probable that there are purely temporal associations between some adverse events and vaccine administration. Since immunization is sometimes mandatory with vaccines usually administered to healthy individuals and their benefits expanded to the community at large, adverse events are difficult to accept. Primary objectives of vaccine-associated adverse events surveillance is the early detection and appropriate and quick response to such events in order to lessen the negative impact on immunization programs and on the health of the individuals. Specific aspects of vaccine postmarketing surveillance are presented.

The 1987 forest fire disaster in California: assessment of emergency room visits.

During a 5-d period that commenced on August 30, 1987, dry lightning strikes ignited more than 1,500 fires that destroyed in excess of 600,000 acres of California forests. To evaluate the public health impact of the smoke on the general population, all hospital emergency rooms located in the six counties most severely affected by smoke or fire were surveyed. Selected hospital information was abstracted for a 2 1/2-wk period during the fires and during two reference periods. During the period of major forest fire activity, visits of persons with asthma and chronic obstructive pulmonary disease increased in number (observed/expected ratios of 1.4 and 1.3, respectively), as did visits of persons with sinusitis, upper respiratory infections, and laryngitis. A few patients with acute respiratory or eye irritation also visited the emergency rooms. Even recognizing the limited sensitivity of emergency room surveys, the overall public health impact was relatively modest. The increased respiratory morbidity detected in this survey, however, supports the notion that persons with pre-existing respiratory disease represent a sensitive subpopulation, who should be targeted for purposes of public health intervention when exposure to forest fire smoke is likely.

Evaluation of immunization coverage in the adult population of Canada.

The immunization coverage of the adult population, availability of records and knowledge of proper schedules were assessed using the Canada Omnibus Survey, a door to door survey of a modified probability sample conducted four times a year. In total, 8021 interviews were completed over four periods. Only 43% of individuals 65 years of age or older reported receiving a dose of influenza vaccine during the year preceding the interview. Twenty-one per cent (38% of those under 25 and 9% of those 65 and older) reported having an immunization booklet at home. Twelve per cent believed that there were no vaccines that they should be receiving regularly. Only 61% of those who believed they should receive some shots regularly knew when the next one was due. Overall, 48% felt they had enough information about the vaccines they should receive. This information will help target immunization programs for the adult population.