Enhanced surveillance for measles in low-incidence territories of the Russian Federation: defining a rate for suspected case investigation.

The rate of case investigation for measles-like illness (MLI) is an important indicator for the quality of measles surveillance in countries targeting measles elimination. However, a benchmark rate is still being discussed. We assessed different rates of investigation in 11 territories of the Russian Federation with low reported measles incidence during the previous 4-7 years. Each territory maintained their existing surveillance activities and also undertook additional surveillance activities for MLI over a 3-year period. The annual routine rate of investigation varied from 0·06 to 1·8/100,000 population; the overall rate of investigation, including enhanced surveillance, varied from 1·4 to 7·2/100,000. Forty-nine (30·8%) of 159 measles cases detected were identified through enhanced surveillance. Based on the results of this study, the Russian Federation concluded that a rate of routine investigation of 2/100,000 provided the best balance between available resources and sensitivity for detection of measles cases.

Pneumococcal bacteremia in Charleston County, South Carolina. A decade later.

Since nationwide surveillance for pneumococcal bacteremia in the United States is not done, community-based studies are useful alternative methods to monitor trends in this disease. Data on the incidence of pneumococcal bacteremia in Charleston County, South Carolina, from 1974 to 1976, have been used to support cost-effective pneumococcal vaccine programs for the elderly. We reevaluated the incidence of pneumococcal bacteremia in Charleston County in 1986 and 1987 to assess whether earlier estimates remained valid given changes in medical practice. During 1986 and 1987, overall annual incidence of pneumococcal bacteremia in Charleston County was 18.7 per 100,000 (95% confidence limits, 13.7 to 23.6 per 100,000), which represents a 2.3-fold increase over the earlier rate. The increase coincided with a 2.2-fold increase in the annual number of blood cultures processed at four Charleston County hospital laboratories from 1975 to 1987 despite only a 1.1-fold increase in the number of patients discharged from these hospitals. Annualized rates increased 2.3-fold for adults more than or equal to 65 years old to 53 per 100,000 and 4.6-fold for children less than 2 years old to 162 per 100,000. The case-fatality rate of bacteremic patients was 18%, compared with 21% in the earlier study. The case-fatality rate for adults more than or equal to 65 years of age was 44%. Ninety-one percent of adults 19 to 64 years old with bacteremia had underlying medical conditions for which pneumococcal vaccine is recommended; all persons 55 to 64 years old had at least one underlying condition. The marked increases in pneumococcal bacteremia rates detected are likely due to more routine culturing of blood from symptomatic patients with pneumococcal disease. These findings emphasize the need for effective programs promoting use of pneumococcal vaccine in high-risk groups, particularly those more than or equal to 65 years old, and the development of a more immunogenic vaccine for children less than 2 years old.

Immunization as a tool to combat antimicrobial resistance.

Vaccines and immunization programs can play a key role in addressing the growing challenge of antimicrobial resistance (AMR). Amongst the high priority vaccines in development are several AMR pathogens, including: Clostridium difficile, Staphylococcus aureus, Streptococcus pneumoniae, Mycobacterium tuberculosis and Neisseria gonorrhoeae. There is evidence that vaccination can reduce the prevalence of AMR microbes, as demonstrated by both pneumococcal and Haemophilus influenza b vaccines. Research continues on many vaccine-preventable diseases, many of these AMR pathogens, including HIV and universal influenza vaccines. Not only do vaccines prevent infections, they can also prevent secondary opportunistic infections from AMR microbes-for example, bacterial pneumonia following influenza infections. The reduced need to treat these opportunistic infections would also mitigate the advance of AMR microbes in our communities. However, vaccines are not a panacea. One downside to the use of vaccines to address AMR is vaccine hesitancy, which undermines efforts to achieve herd immunity, but this is being increasingly addressed by public health education campaigns.

Serum antibody response to pneumococcal vaccine in children with nephrotic syndrome.

Children with nephrotic syndrome are susceptible to serious pneumococcal disease and may be immunodeficient on the basis of abnormal humoral immune responses to natural antigens or immunoglobulin loss during relapse. As part of an ongoing study to evaluate pneumococcal anticapsular antibody concentration and immunologic competence, 27 steroid-responsive and six steroid-resistant patients with nephrotic syndrome, and 12 age-matched control subjects, were vaccinated with polyvalent pneumococcal vaccine. Antibody responders were defined as patients with at least a twofold increase in antibody after vaccination as well as an antibody concentration greater than 200 ng of anticapsular antibody nitrogen per milliliter (ngN/ml) after vaccination. Pneumococcal antibody concentrations before and after vaccination were significantly depressed in steroid-resistant patients when compared with control subjects (P less than .002) and with the steroid-responsive nephrotic syndrome group (P less then .001). Steroid-responsive nephrotic children who were not receiving corticosteroid therapy at the time of vaccination had significantly higher antibody concentrations to five pneumococcal types before vaccination and to seven types after vaccination compared with control subjects (P less than .05). Fewer steroid-responsive patients receiving corticosteroids achieved antibody concentrations greater than or equal to 200 ngN/ml against type 19F compared with patients not receiving steroids or with control subjects (P less than .05). These results suggest that pneumococcal vaccine is immunogenic in children with steroid-responsive nephrotic syndrome and may protect these patients from disease due to pneumococcal types contained in the vaccine.

Pneumococcal vaccination. Controversies and opportunities.

The morbidity and mortality associated with pneumococcal infections are preventable in many high-risk individuals by immunization with 23-valent pneumococcal vaccine. While the clinical effectiveness of the current vaccine is less than ideal, use of the vaccine is cost effective. In spite of recommendations for pneumococcal vaccination of elderly and other high-risk persons, and federal reimbursement for vaccination Medicare enrollees, it was estimated in 1985 that only 10% to 15% of this target population was immunized. Strategies for immunizing high-risk individuals with pneumococcal vaccine need to involve physicians, public health professionals, health advocacy groups, and persons in the targeted populations.

Pneumococcal vaccination in a remote population of high-risk Alaska Natives.

In response to an increasing prevalence of serious pneumococcal disease among adult Alaska Natives of northwest Alaska, a 3-year program was begun in 1987 to identify residents of that remote region who were at high risk for developing invasive pneumococcal disease, to determine their pneumococcal vaccination status, and to deliver vaccine to at least 80 percent of those at risk. After reviewing public health nursing and Indian Health Service data bases, the authors identified 1,337 persons, 20 percent of the 6,692 residents of the region, at high risk for invasive pneumococcal infection, defined either by having a specific chronic disease or by age criteria. Cardiovascular disease and alcoholism were the two most common chronic diseases. Only 30 percent of those determined to be at high risk had received one or more doses of pneumococcal vaccine previously. Half of those persons had received their most recent vaccination 6 or more years earlier. The program used both customary and innovative methods to deliver 23-valent polysaccharide vaccine to 1,046 of those at high risk (78 percent), including 388 persons who were revaccinated. At the completion of the project, 1,123 persons, 84 percent of those at high risk, had received at least 1 dose. They included 1,088 persons, 81 percent of those at high risk, with vaccination within the previous 5 years as a result of the project, compared with a 15-percent rate prior to the vaccination phase of the project. The program demonstrated that high levels of vaccination against pneumococcal disease, exceeding Year 2000 objectives of 60 percent, are attainable in a remote rural Alaskan population.

Risk factors for infection with verocytotoxigenic Escherichia coli in cattle on Ontario dairy farms.

Risk factors for prevalent infection with verocytotoxigenic Escherichia coli (VTEC) were studied in a random sample of 886 cows and 592 calves under 3 months of age on 80 randomly selected dairy farms in southern Ontario. Fecal-culture supernatants from each animal were screened for verocytotoxicity using a Vero cell assay (VCA) and for verocytotoxin (VT) genes by a polymerase chain reaction (PCR) procedure. Up to 20 F. colt isolates from positive samples were tested for VT production using VCA and PCR. VTEC isolates were serotyped. Farm managers were interviewed using a standardized questionnaire to obtain information on farm- and individual animal-level management practices and characteristics. There was a significant (P < 0.001) positive association between age of calves and their VTEC infection status, and calves were significantly more likely to be infected than cows. The proportion of calves infected on the farm was positively associated with both the use of regular pails for feeding calves (as opposed to nipple bottles or nipple pails) and bringing new animals into the herd in the previous year.

Preventing congenital rubella infection in the European Region of WHO: 2010 target.

The World Health Organisation (WHO) Regional Office for Europe has recently published a strategic plan and surveillance guidelines for measles and congenital rubella infection. The strategy prioritises measles control activities but encourages the introduction of rubella vaccine when measles vaccine coverage has reached >90 %; although, many western European countries with suboptimal measles vaccine coverage are already using the combined measles, mumps and rubella (MMR) vaccine. Women in these countries may have an especially high risk of having an infant with congenital rubella syndrome. WHO is seeking to improve the surveillance for rubella and congenital rubella syndrome as a means to obtain better information on the burden of these diseases and engage policy decision makers in the need to support the WHO European Region's strategies for rubella.

Preventing congenital rubella infection in the European Region of WHO: 2010 target.

The World Health Organisation (WHO) Regional Office for Europe has recently published a strategic plan and surveillance guidelines for measles and congenital rubella infection. The strategy prioritizes measles control activities but encourages the introduction of rubella vaccine when measles vaccine coverage has reached >90 %; although, many western European countries with suboptimal measles vaccine coverage are already using the combined measles, mumps and rubella (MMR) vaccine. Women in these countries may have an especially high risk of having an infant with congenital rubella syndrome. WHO is seeking to improve the surveillance for rubella and congenital rubella syndrome as a means to obtain better information on the burden of these diseases and engage policy decision makers in the need to support the WHO European Region's strategies for rubella.

Prevalence of Salmonella and multiple antimicrobial-resistant Salmonella in California dairies.

A cross-sectional survey was conducted on 75 randomly selected dairies in one California county. Salmonella was isolated from 12 (16%) dairies; S newport was isolated from 6 (8%). Chloramphenicol-resistant S newport and S dublin were isolated from 8 (10.7%) dairies. Dairies with Salmonella had higher average calf mortality rates (P = 0.064; odds ratio [OR], 3.8). Dairies with S newport had a greater than expected occurrence of illnesses in adult cows compared with dairies with no S newport (P = 0.048; OR, 6.7) or with no Salmonella serotypes isolated (P = 0.047; OR, 6.9). Dairies with chloramphenicol-resistant Salmonella were more likely to have used chloramphenicol during the preceding 18-month period compared with dairies with chloramphenicol-susceptible Salmonella or no Salmonella (P = 0.023; OR, 9.5).

Salmonella typhimurium DT104: a virulent and drug-resistant pathogen.

Salmonella typhimurium phage type (PT) or definitive type (DT) 104 is a virulent pathogen for humans and animals, particularly cattle. It has been isolated increasingly from humans and animals in the United Kingdom and several other European countries and, more recently, in the United States and Canada. Humans may acquire the infection from foods of animal origin contaminated with the infective organism. Farm families are particularly at risk of acquiring the infection by contact with infected animals or by drinking unpasteurized milk. The symptoms in cattle are watery to bloody diarrhea, a drop in milk production, pyrexia, anorexia, dehydration and depression. Infection may result in septicemic salmonellosis and, upon necropsy, a fibrinonecrotic enterocolitis may be observed. The infection occurs more commonly in the calving season than at other times. Feedlot cattle and pigs may also be affected. Prolonged carriage and shedding of the pathogen may occur. Symptoms in humans consist of diarrhea, fever, headache, nausea, abdominal pain, vomiting, and, less frequently, blood in the stool. Salmonella typhimurium DT104 strains are commonly resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline.

A Canadian multicentre case-control study of sporadic Escherichia coli 0157:H7 infection.

OBJECTIVE: To evaluate further risk factors for Escherichia coli 0157:H7 infection including consumer preferences related to the consumption of ground beef and the role of person-to-person transmission of this infection. PATIENTS AND METHODS: A case-control study of sporadic E coli 0157:H7 infection was undertaken in five Canadian cites from June to December 1991. One hundred cases of E coli 0157:H7 infection were age- and sex-matched to 200 neighbourhood controls. Cases and controls were interviewed face-to-face to obtain information on potential risk factors for infection and health outcomes. Daycare providers of case and control children were interviewed regarding risk factors for infection at the institutional level. Contacts of cases and controls who reported diarrhea in the seven days before the case onset date were also interviewed about their symptoms and risk factors. RESULTS: All cases had diarrhea during the course of their illness and 90 (90%) reported bloody diarrhea. Four (4%) were reported to have developed hemolytic uremic syndrome; however, there were no fatalities. Sixty-one (61%) of patients were hospitalized. Two variables were associated with infection in the final conditional logistic regression model: eating pink hamburger patties (odds ratio = 12.4, P=0.0001, population attributable fraction =40.2%) and contact with a nonhousehold member suffering from diarrhea (odds ratio = 7.0, P=0.0054, population attributable fraction = 10.3%) in the seven days before illness. Forty per cent of cases and controls who indicated that they prefer well done hamburgers said they would eat a 'pink' hamburger if served to them rather than ask that the hamburger be cooked longer. CONCLUSIONS: Health care workers should remain vigilant in their efforts to educate the public as to the risks associated with the consumption of ground beef that is inadequately cooked, and the importance of personal hygiene in the prevention of enteric illness.

Pneumococcal bacteremia in Hawaii: initial findings of a pneumococcal disease prevention project.

The Hawaii Department of Health (DOH) recently established a pneumococcal disease initiative to determine the scope of serious pneumococcal disease in residents of Hawaii and to investigate methods of increasing vaccine utilization in the State. The initial phase of the project involved a review of pneumococcal bacteremia at all 38 microbiology laboratories in Hawaii during 1986 and 1987. Two hundred twenty-two residents with bacteremia were identified. Eighty-six percent of adults had pneumonia as the primary source of bacteremia. In children greater than 5 years old, pneumonia was present in 24%, otitis media in 35%, and meningitis in 11%. Bacteremia with no apparent focus of infection was found in 30% of children. The overall annual incidence of pneumococcal bacteremia was 9/10(5) population. Rates were highest in children greater than 2 years old (103/10(5] and persons greater than or equal to 65 years old (22/10(5]. These are similar to rates reported from other populations in the United States during the 1970s and early 1980s, but are less than those detected in 2 more recent population-based studies. The overall case-fatality rate in our study was relatively low (16%); however, 35% of persons greater than or equal to 65 years old died. A record of previous pneumococcal vaccination was found in the medical records of only 2 (1%) patients. Our study confirms that pneumococcal bacteremia causes significant morbidity and mortality among elderly residents of Hawaii and suggests that vaccine coverage is very low among this high-risk population. Phase 2 of the initiative included surveys of Hawaii physicians and the public to ascertain attitudes toward pneumococcal immunization.(ABSTRACT TRUNCATED AT 250 WORDS)