Epidemic meningococcal disease in Nairobi, Kenya, 1989. The Kenya/Centers for Disease Control (CDC) Meningitis Study Group.

An epidemic of meningococcal disease occurred in Nairobi, Kenya, during 1989, outside the "meningitis belt" of sub-Saharan Africa. About 3800 cases occurred between April and November (250/100,000 population). The case-fatality rate was 9.4% among hospitalized patients. Areas that included Nairobi's largest slums had particularly high attack rates. The epidemic displayed an unusual age distribution, with high attack rates among those 20-29 years old. A vaccination campaign was conducted. By early January, the weekly case count had fallen to 25 from a high of 272 (in September). A case-control study estimated the vaccine efficacy to be 87% (95% confidence interval, 67%-95%). A model estimated that the vaccination campaign reduced the number of cases by at least 20%. Multilocus enzyme electrophoretic typing demonstrated that the strain responsible for this large epidemic is closely related to strains that caused other recent epidemics, documenting further spread of what may be a particularly virulent clonal complex of group A Neisseria meningitidis.     

Epidemiological pattern of meningococcal disease in Valencia, Spain. Impact of a mass immunization campaign with meningococcal C polysaccharide vaccine

The objective of this study was to define the epidemiological pattern of meningococcal disease in the autonomous region of Valencia, Spain, and the impact of a mass immunization campaign against serogroup C meningococcus. Data were obtained from a prospective surveillance program for invasive bacterial diseases in children < 15 y of age that began in the Valencia region on 1 December, 1995. During the period 1996-98, 213 cases of meningococcal disease were detected, representing an annual incidence of 11.3/100,000 children < 15 y. Serogroup C accounted for 31% and 38.5% of cases in 1996 and 1997, respectively (annual incidences of 2.9 and 5.4 cases/100,000 children < 15 y). An immunization campaign with the meningococcal C polysaccharide vaccine, which included all persons between 18 months and 19 y of age, began in late 1997 (vaccination coverage of 86%). In 1998, the annual incidence of meningococcal C disease fell to 1.4 cases per 100,000 children < 15 y of age. These results mirror the increase in the reported incidence of serogroup C meningococcal disease in Spain in the 1990s, a trend that was reversed after the introduction of the mass vaccination campaign. Meningococcal polysaccharide vaccine seems to be an effective public health tool for the management of this serious communicable disease.     

Improved equity in measles vaccination from integrating insecticide‐treated bednets in a vaccination campaign,Madagascar

Objective To evaluate the effect of integrating ITN distribution on measles vaccination campaign coverage in Madagascar. Methods Nationwide cross‐sectional survey to estimate measles vaccination coverage, nationally, and in districts with and without ITN integration. To evaluate the effect of ITN integration, propensity score matching was used to create comparable samples in ITN and non‐ITN districts. Relative risks (RR) and 95% confidence intervals (CI) were estimated via log‐binomial models. Equity ratios, defined as the coverage ratio between the lowest and highest household wealth quintile (Q), were used to assess equity in measles vaccination coverage. Results National measles vaccination coverage during the campaign was 66.9% (95% CI 63.0–70.7). Among the propensity score subset, vaccination campaign coverage was higher in ITN districts (70.8%) than non‐ITN districts (59.1%) (RR = 1.3, 95% CI 1.1–1.6). Among children in the poorest wealth quintile, vaccination coverage was higher in ITN than in non‐ITN districts (Q1; RR = 2.4, 95% CI 1.2–4.8) and equity for measles vaccination was greater in ITN districts (equity ratio = 1.0, 95% CI 0.8–1.3) than in non‐ITN districts (equity ratio = 0.4, 95% CI 0.2–0.8). Conclusion Integration of ITN distribution with a vaccination campaign might improve measles vaccination coverage among the poor, thus providing protection for the most vulnerable and difficult to reach children.     

Study of the dog population and the rabies control activities in the Mirigama area of Sri Lanka

The national health authorities of Sri Lanka have adopted a combined strategy of rabies vaccination and stray dog removal to control endemic dog rabies. Despite the control efforts, an increase of animal and human rabies cases has occurred since 1994. As a consequence, a project to evaluate the national rabies control program has been started and a study focussing on the dog population and rabies control activities in a limited area of Mirigama was conducted. Information on canine abundance and the accessibility of dogs for rabies vaccination was obtained by a household survey, vaccination of dogs against rabies at several vaccination points, collar-marking, and transect line recapture. The number of unvaccinated dogs was estimated by using Bayesian methodology. The estimated number of dogs per square kilometre was 87 (95% credibility interval: 80, 93) for owned dogs and 108 (100, 116) for owned and ownerless dogs. Coverage after the immunisation campaign was 57.6% (53.3, 61.9%) if vaccination at the vaccination points was considered and 66% (60.4, 72.0%) if recently provided vaccination by private veterinarians was also taken into account. The proportion of households with at least one dog vaccinated varied between 59.1 and 94.2% within the catchment area of the different vaccination points. Unvaccinated dogs were puppies (12%), ownerless dogs (57%), and owned dogs, which were not presented for vaccination (31%). In order to improve the rabies immunisation coverage among dogs and to achieve complete elimination of rabies it was recommended that the 95% catchment area of each vaccination point be assessed, the distribution of vaccination points in the vaccination area be redefined if necessary, a system for the vaccination of dogs missing the vaccination campaign for dog owner-specific reasons be established, and an inexpensive marking system be used for vaccinated dogs.     

Diphtheria in Estonia, 1991-1996

Clinical diphtheria reappeared in Estonia in 1991. Between 1991 and 1996, 61 cases and 5 deaths occurred; 19 cases were among children 5-9 years of age, and 11 were among persons 40-49 years of age. From 1993-1995, vaccine supplies donated by Finland were used in vaccination programs. In 1995, the International Federation of Red Cross and Red Crescent Societies and the Estonian Red Cross launched a mass vaccination campaign targeting the adult population. By the end of 1997, it was estimated that 46% of adults had received at least one dose of vaccine. Although the vaccination campaigns did not target the pediatric population, vaccination coverage in school-aged children remained high due to continuing routine vaccination programs. The reappearance and epidemic of clinical diphtheria cases and the mass vaccination campaign efforts demonstrated that preventive measures are important and must be maintained in order to keep diphtheria under control.     

Perspectives of Allergists/Immunologists on the 2009–2010 H1N1 Vaccination Effort

Background. Persons with high-risk conditions such as asthma were a target group for national H1N1 vaccine recommendations. Allergists/immunologists (allergists) are a provider group that could vaccinate persons with asthma and other high-risk conditions. Their level of participation in and experiences with the 2009–2010 H1N1 vaccination campaign are unknown. Objective. To describe the experiences of allergists related to the 2009–2010 H1N1 vaccination campaign. Methods. A cross-sectional, mailed survey of a national sample of 1955 allergists providing outpatient care was conducted in June–September 2010. Results. The overall response rate was 72%. Most allergists “strongly recommended” H1N1 vaccine for children, and most “recommended” or “strongly recommended” vaccine for adults. The majority (71%) agreed to participate in the H1N1 vaccine campaign and received vaccine. Vaccine supply was a significant challenge, but otherwise few major problems were experienced with administering H1N1 vaccine. The majority of respondents, particularly among those who participated in the 2009–2010 H1N1 vaccination campaign, felt they would be very likely to vaccinate in the event of future influenza pandemic. Conclusions. The experiences of allergists in the H1N1 vaccine campaign were generally positive. Most allergists are willing to serve as vaccinators in future influenza pandemics, which will help facilitate broad access to vaccine for patients with asthma and other high-risk conditions.     

Interruption of indigenous measles transmission in Bolivia since October 2000

Measles incidence in Bolivia declined after the introduction of campaign strategies in the 1980s. From 1990 to 1993, the peak incidence of measles (59 cases/100,000 population) was in 1992. In 1994, after the goal of interruption of measles transmission was adopted, a national vaccination campaign targeting children <15 years old was conducted and achieved 96% coverage. During 1995-1997, cases declined, although routine coverage was <90% in most years. During 1998-2000, a nationwide epidemic occurred among 2567 case-patients, most of whom were unvaccinated. A national vaccination campaign, with strong supervision, was conducted during November and December 1999 and targeted areas with low coverage. Only 122 cases were confirmed in 2000, with the last confirmed case occurring in October. Crucial to the control of the outbreak were sufficient resources and political support, intensive local planning, door-to-door vaccination with strict supervision, and rapid house-to-house coverage monitoring that improved accountability at the local level and timely and thorough outbreak investigations.     

Impact of a mass vaccination campaign against a meningitis epidemic in a refugee camp

Serogroup A meningococcus epidemics occurred in refugee populations in Zaire in August 1994. The paper analyses the public health impact of a mass vaccination campaign implemented in a large refugee camp. We compared meningitis incidence rates from 2 similar camps. In Kibumba camp, vaccination was implemented early in the course of the epidemic whilst in the control camp (Katale), vaccination was delayed. At a threshold of 15 cases per 100 000 population per week an immunization campaign was implemented. Attack rates were 94 and 134 per 100 000 in Kibumba and Katale respectively over 2 months. In Kibumba, one week after crossing the threshold, 121 588 doses of vaccine were administered covering 76% of all refugees. Vaccination may have prevented 68 cases (30% of the expected cases). Despite its rapid institution and the high coverage achieved, the vaccination campaign had a limited impact on morbidity due to meningitis. In the early phase in refugee camps, the relative priorities of meningitis vaccination and case management need to be better defined.     

Assessment of vaccination coverage among adults 30-49 years of age following a mass diphtheria vaccination campaign: Ukraine, April 1995

Ukraine has been experiencing epidemic diphtheria since 1991. In efforts to control this epidemic, a mass vaccination campaign was held in April 1995. Persons not vaccinated in the previous 3 years were considered eligible for vaccination with tetanus-diphtheria toxoids (Td). Two cluster sample surveys were conducted to determine vaccination coverage achieved. In the urban and rural survey areas, respectively, 628 and 618 persons 30-49 years of age were interviewed. Fifty-nine percent of urban and 58% of rural participants were eligible for vaccination. During the vaccination campaign, 58% (95% confidence interval [95% CI], 47.1-69.2) of eligible persons received Td in the urban area, compared with 92% (95% CI, 89.2-95.3) in the rural area. Apparent barriers to vaccination included misconceptions about the safety, efficacy, and need for booster doses of Td. Future vaccination campaigns should include targeted information and education messages. Mass vaccination campaigns can be successful in vaccinating large numbers of adults; however, in urban areas, additional efforts may be required to achieve levels of coverage adequate to confer herd immunity and interrupt the diphtheria epidemic.     

Economics of an adolescent meningococcal conjugate vaccination catch-up campaign in the United States.

BACKGROUND: In June 2005, the Advisory Committee on Immunization Practices recommended the newly licensed quadrivalent meningococcal conjugate vaccine for routine use among all US children aged 11 years. A 1-time catch-up vaccination campaign for children and adolescents aged 11-17 years, followed by routine annual immunization of each child aged 11 years, could generate immediate herd immunity benefits. The objective of our study was to analyze the cost-effectiveness of a catch-up vaccination campaign with quadrivalent meningococcal conjugate vaccine for children and adolescents aged 11-17 years. METHODS: We built a probabilistic model of disease burden and economic impacts for a 10-year period with and without a program of adolescent catch-up meningococcal vaccination, followed by 9 years of routine immunization of children aged 11 years. We used US age- and serogroup-specific surveillance data on incidence and mortality. Assumptions related to the impact of herd immunity were drawn from experience with routine meningococcal vaccination in the United Kingdom. We estimated costs per case, deaths prevented, life-years saved, and quality-adjusted life-years saved. RESULTS: With herd immunity, the catch-up and routine vaccination program for adolescents would prevent 8251 cases of meningococcal disease in a 10-year period (a 48% decrease). Excluding program costs, this catch-up and routine vaccination program would save US$551 million in direct costs and $920 million in indirect costs, including costs associated with permanent disability and premature death. At $83 per vaccinee, the catch-up vaccination would cost society approximately $223,000 per case averted, approximately $2.6 million per death prevented, approximately $127,000 per life-year saved, and approximately $88,000 per quality-adjusted life-year saved. Targeting counties with a high incidence of disease decreased the cost per life-year saved by two-thirds. CONCLUSIONS: Although costly, catch-up and routine vaccination of adolescents can have a substantial impact on meningococcal disease burden. Because of herd immunity, catch-up and routine vaccination cost per life-year saved could be up to one-third less than that previously assessed for routine vaccination of children aged 11 years.     

The elimination of indigenous measles transmission in England and Wales

Following a school-based measles-rubella vaccination campaign in November 1994, enhanced surveillance of measles, including IgM antibody testing of oral fluid from clinically diagnosed case-patients, was introduced in England and Wales. Between 1995 and 2001, 665 cases of measles were confirmed, including 371 (56%) confirmed only by IgM detection in oral fluid. Two hundred thirty-nine cases (36%) were sporadic and 426 (64%) were associated with 61 clusters. Fifty-four (23%) of the 239 sporadic cases and 26 (43%) of the 61 clusters were associated with a probable or possible importation of infection from overseas, and a wide variety of genotypes were identified in each calendar year. The effective reproduction number for measles over the period was estimated to be below 0.7. These data suggest that most measles in the UK is acquired following limited transmission from an imported infection, and they confirm that measles elimination has been achieved and sustained over this period.     

Studies of influenza vaccination among elderly nursing home residents

We conducted a questionnaire survey of influenza vaccination among elderly nursing home residents, and investigated the actual condition and the view of vaccination of elderly people. There was 272 elderly residents in Nagoya-shi, Kouseiin Medical Welfare Center, they were classified into the bed ridden group; 195cases (71.7%) according to the independence in activities of daily living, and 132cases (48.5%) were evaluated as the disturbance of community ability group. The number of vaccination in 2002/2003 was 163 residents (59.9%). When the vaccination group (163cases) was compared with the non-vaccination group (109cases), it becomes clear that the later has much bedridden or dementia. The reply of questionnaire was obtained from 139 cases (51.1%) among 272 residents. As a reason of the residents who received vaccine, a prevention was 70.2%, mostly over whelmingly. The following were 17.0% of a custom of annual vaccination, and the recommendation by doctor and family were 5.3% and 3.2%, respectively. The main reasons for having not received a vaccine was inability of recoganization 22.2%. The afraid of adverse reaction or allergy, the ache of a injection was following 17.8%, respectively. In order to raise the rate of the vaccination in elderly nursing home residents, we should make into consideration that the educational campaign of the safety of vaccine and how to develop motivation for vaccination to the elderly with cognitive decline.     

Stability of the age distribution of measles cases over time during outbreaks in Bangladesh, 2004-2006

Despite recommendations from WHO to conduct measles outbreak response vaccination campaigns based on the age distribution of cases at the beginning of an outbreak, few data exist to specifically examine whether the age distribution of cases remains constant over time in a measles outbreak. This analysis explores this question with use of measles outbreak surveillance data from Bangladesh from the period 2004-2006. Pearson χ(2) tests were conducted of age distributions over 2 periods during 41 large laboratory-confirmed measles outbreaks. Statistically significant changes in age distribution over time were observed in 24% of the outbreaks. No single pattern was detected in the shifts in age distribution; however, an increase in the proportion of cases occurring among infants <9 months of age was evident in 6 outbreaks. These findings suggest a need to consider the possibility of a shift in the age distribution over time when planning an outbreak response vaccination campaign.     

Marketing paediatric influenza vaccination: results of a major metropolitan trial

Please cite this paper as: Van Buynder et al. (2010) Marketing paediatric influenza vaccination: results of a major metropolitan trial. Influenza and Other Respiratory Viruses 5(1), 33–38. Objectives After a cluster of rapidly fulminant influenza related toddler deaths in a Western Australian metropolis, children aged six to 59 months were offered influenza vaccination in subsequent winters. Some parental resistance was expected and previous poor uptake of paediatric influenza vaccination overseas was noted. A marketing campaign addressing barriers to immunization was developed to maximise uptake. Design Advertising occurred in major statewide newspapers, via public poster displays and static ‘eye‐lite’ displays, via press releases, via a series of rolling radio advertisements, via direct marketing to child care centres, and via a linked series of web‐sites. Parents were subsequently surveyed to assess reasons for vaccination. Main Outcome Results The campaign produced influenza vaccination coverage above that previously described elsewhere and led to a proportionate reduction in influenza notifications in this age group compared to previous seasons. Conclusions Influenza in children comes with significant morbidity and some mortality. Paediatric influenza vaccination is safe, well tolerated and effective if two doses are given. A targeted media campaign can increase vaccine uptake if it reinforces the seriousness of influenza and addresses community ‘myths’ about influenza and influenza vaccine. The lessons learned enabling enhancements of similar programs elsewhere.     

Measles epidemic and investigation of the vaccination history in Chiba Prefecture in 2000. A report from Chiba epidemiological surveillance of tuberculosis and infectious diseases

A middle-scale epidemic of measles was occurred in Chiba Prefecture, from the beginning of the year in 2000 to September. The Chiba epidemiological surveillance of tuberculosis and infectious diseases committee conducted an investigation of the vaccination history of measles patients, to obtain the prevailing situation of measles and the efficacy of the vaccination. This report summarized results of the epidemiological investigation of measles vaccination history. A total of 1,665 cases were reported during the period. The ratio of the under 1-year-old (who usually do not receive measles vaccine) to all reported cases was 11.4%. The ratio of the vaccinees for the reported cases was 11.8% and this ratio increased in the 5 years old or over. In particular, the 9-year-old age group (26.2%), and 10-14-year-old age group (23.3%) showed a higher ratio than the other age groups. These results indicate that early vaccine inoculation to the under 1-year old group and improvement of the vaccination rate are necessary to prevent measles epidemic. The results also suggest revaccination to higher age groups might be effective.     

A review of the current impact of measles in the People's Republic of China

Before the vaccine era, epidemics of measles occurred in alternate years on the mainland of China. During epidemic years the annual incidence was as high as 1,000-5,000 cases/100,000 population, with a fatality rate of 1% to 2%. In 1965, when highly attenuated measles vaccine was developed in China, a vaccination campaign was launched throughout the country. In its early years, the immunization program was not implemented simultaneously at all places, and outbreaks that continued to occur in some areas resulted in a moderate local incidence of measles despite a decline in the overall incidence. From the late 1970s on, stronger measures were taken by local health authorities with regard to measles vaccination. By 1980 the incidence had dropped further; in that year the number of reported cases was 570,037, with 3,862 deaths. Both morbidity and mortality related to measles dropped drastically after vaccination from levels in the prevaccine era, but measles still accounts for an appreciable proportion of all cases of infectious disease.     

Impact of the meningococcal C conjugate vaccine in Spain: an epidemiological and microbiological decision

The new meningococcal C conjugate vaccine became available in Spain and was included in the infant vaccination schedule in 2000. A catch-up campaign was carried out in children under six years of age. As a consequence, the incidence of meningococcal disease caused by serogroup C has fallen sharply during the last three epidemiological years in Spain. The risk of contracting serogroup C disease in 2002/2003 fell by 58% when compared with the season before the conjugate vaccine was introduced. There was also an important decrease in mortality. Three deaths due to serogroup C occurred in the age groups targeted for vaccination in 2002/2003, compared with 30 deaths in the same age groups in the season before the launch of the vaccine campaign. In the catch-up campaign the vaccine coverage reached values above 92%. For the 2001, 2002 and 2003 routine childhood immunisation programme coverage values ranged from 90% to 95%. During the past three years a total of 111 cases of serogroup C disease have been reported in patients in the vaccine target group. Most of the vaccination failures occurred during the epidemiological year 2002/2003. Eight (53%) vaccine failures occurred in children who had been routinely immunised in infancy, and could be related to a lost of protection with time since vaccination. The isolation of several B:2a:P1.5 strains (ST-11 lineage) is noteworthy. These may have their origin in C:2a:P1.5 strains which, after undergoing genetic recombination at the capsular operon level, express serogroup B. These strains could have relevant epidemic potential.     

Evaluation of urban measles mass campaigns for children aged 9-59 months in Mali

There are an estimated 234,000 cases of measles and 13,851 measles-related deaths per year in Mali. In 1998 and 1999, 548,309 children aged 9-59 months were vaccinated against measles during mass campaigns in urban centers across Mali. After the first campaign, measles incidence decreased by 95% in districts encompassing vaccinated urban centers and by 41% in nonvaccinated districts. There was no shift in the proportion of cases by age group in vaccinated centers. Measles in vaccinated districts after the campaign was likely related to persistent transmission in age groups not targeted for vaccination and among children living in nonvaccinated districts. The second campaign (1999) did not change the incidence of measles in vaccinated compared with nonvaccinated centers. Urban mass measles vaccination probably did not affect overall measles transmission in Mali. Mass vaccination of all children in Mali, targeting a larger age group, will be necessary to reach measles control objectives.     

Impact of measles in France

Although measles vaccine has been licensed since 1968, immunization against measles has not met with much success in France, partly because the disease is no longer feared. The level of vaccination coverage appears to be less than 20%. Indeed, the present epidemiologic situation is similar to the natural situation in a developed country. A multicenter, retrospective hospital survey revealed that 1,157 patients with measles were hospitalized during a 30-month period in five areas (total population, 4.2 million). Analysis of the preliminary results of this survey and of available national data showed an incidence of 5.6-7.5 cases per 1,000 population; a hospitalization rate of one per 10,000; a death rate of 0.56 per 1 million; and a disability rate of 0.48 per 1 million. Encephalitis (the definition of which should be reappraised) occurred once in 2,850 cases, and subacute sclerosing panencephalitis was not rare (incidence, one case per 2.6 million people). The problem posed by measles is sufficiently grave to justify a national campaign urging the widespread vaccination of children.     

Measles incidence before and after mass vaccination campaigns in Burkina Faso

Burkina Faso conducted mass measles vaccination campaigns among children aged 9 months to 4 years during December 1998 and December 1999. The 1998 campaign was limited to six cities and towns, while the 1999 campaign was nationwide. The last year of explosive measles activity in Burkina Faso was 1996. Measles surveillance data suggest that the 1998 urban campaigns did not significantly impact measles incidence. After the 1999 national campaign, the total case count decreased during 2000 and 2001. However, 68% of measles cases occurred among children aged 5 years or older who were not included in the mass vaccination strategy. During 2000 and 2001, areas with high measles incidence were characterized by low population density and presence of mobile and poor populations. Measles control strategies in Sahelian Africa must balance incomplete impact on virus circulation with cost of more aggressive strategies that include older age groups.