Biomedical subjects

C Vitek

Publications and source records attributed to C Vitek.

8 recordsLinked to original sources

PubMed2000

Successful control of epidemic diphtheria in the states of the Former Union of Soviet Socialist Republics: lessons learned.

Epidemic diphtheria reemerged in the Russian Federation in 1990 and spread to all Newly Independent States (NIS) and Baltic States by the end of 1994. Factors contributing to the epidemic included increased susceptibility of both children and adults, socioeconomic instability, population movement, deteriorating health infrastructure, initial shortages of vaccine, and delays in implementing control measures. In 1995, aggressive control strategies were implemented, and since then, all affected countries have reported decreases of diphtheria; however, continued efforts by national health authorities and international assistance are still needed. The legacy of this epidemic includes a reexamination of the global diphtheria control strategy, new laboratory techniques for diphtheria diagnosis and analysis, and a model for future public health emergencies in the successful collaboration of multiple international partners. The reemergence of diphtheria warns of an immediate threat of other epidemics in the NIS and Baltic States and a longer-term potential for the reemergence of vaccine-preventable diseases elsewhere. Continued investment in improved vaccines, control strategies, training, and laboratory techniques is needed.

Adult↗

PubMed2000

Epidemic investigation of diphtheria, Republic of Kazakhstan, 1990-1996.

The diphtheria epidemic that began in Russia in 1990 reached Kazakhstan in 1992 when 45 case-patients (a 50% increase over 1991) were reported. In 1993, 82 case-patients were reported, and 489 were reported in 1994. The epidemic peaked in 1995 when 1105 case-patients were reported (incidence rate=6.7/100,000 population). In 1996, after public health practice modifications and several mass vaccinations, 455 case-patients were reported. From 1990 to 1996, children </=14 years old represented 35% (2234) of the reported case-patients (and 33% of the population) but had a disproportionate share (49%) of the fatalities. Females represented 63% of the adult case-patients. In 1996, 297 (65%) of 455 case-patients and 26 (84%) of 31 fatalities were unvaccinated. Kazakhstan controlled the diphtheria epidemic by using a multifaceted public health strategy of prevention and control, which included changing the routine immunization schedule, modifying the official list of contraindications to vaccination, conducting mass campaigns to vaccinate persons, and treating close contacts of case-patients with antibiotics.

Adolescent↗

PubMed2000

How many doses of diphtheria toxoid are required for protection in adults? Results of a case-control study among 40- to 49-year-old adults in the Russian Federation.

During the Russian diphtheria epidemic of the 1990s, adults had an unexpectedly high rate of disease. A retrospective, matched case-control study was done to measure the effectiveness of one, two, or three or more doses of diphtheria toxoid against diphtheria among 40- to 49-year-old Russians. Thirty-nine diphtheria case-patients and 117 controls were studied. Previous vaccinations were included if one dose was received within the previous 10 years. Five cases (13%) and 33 controls (28%) had received three or more doses of vaccine. The matched odds ratio was 0.3 (95% confidence interval, 0.1-0.9) for three or more doses compared with no doses, which was a vaccine effectiveness of 70% (95% confidence interval, 10-90). A trend existed toward milder disease with increasing doses (chi2 test for trend, P=.02). The results suggest that Russian adults, who were unlikely to have acquired immunity to diphtheria through immunization or natural infection, required at least three doses of diphtheria toxoid for reliable protection against disease.

Adult↗

PubMed2000

Epidemic diphtheria in the Newly Independent States of the Former Soviet Union: implications for diphtheria control in the United States.

The re-emergence of diphtheria in the Newly Independent States of the former Soviet Union in the 1990s raised global awareness of the potential for resurgent disease in countries with long-standing immunization programs. In the United States, the large population of susceptible adults and the possibility of a reintroduction of toxigenic strains of diphtheria create a setting in which diphtheria could spread. In addition, at least one focus of continued circulation of endemic toxigenic Corynebacterium diphtheriae has been identified. Few physicians now have expertise in the diagnosis and treatment of persons with diphtheria, and laboratory capacity is lacking throughout the country. These concerns highlight the importance of maintaining high levels of age-appropriate diphtheria toxoid vaccination, surveillance, accessible and reliable laboratory testing, and training of health care providers. Although the risk of resurgence of diphtheria in the United States is low, public health authorities must ensure that the capacity to recognize, diagnose, and control diphtheria is maintained.

Age Factors↗

PubMed1998

Measles outbreaks in Micronesia, 1991 to 1994.

BACKGROUND: Several islands in Micronesia experienced large measles outbreaks, during 1991 through 1994. Except for Guam, none of the islands had reported measles outbreaks during the previous 20 years. METHODS: To characterize the outbreaks, measles surveillance data, hospital records and death certificates were reviewed. Preoutbreak vaccination coverage rates were assessed by reviewing public health vaccination records. Viral isolates were genetically sequenced to determine the source of transmission. Linear regression analysis was performed to assess the effectiveness of outbreak control measures. RESULTS: Between 1991 and 1994 more than 1300 measles cases and 16 measles-related deaths were reported in Micronesia. Preoutbreak vaccination coverage rates among 2-year-old children were 55 to 94%. Genetic sequencing of the viral isolates and epidemiologic investigations suggested transmission between islands and new importations from outside of Micronesia. The highest attack rates were among children ages < 5 years (20/1000) and 10 to 19 years (38/1000). Compared with attack rates among children ages < 1 and 10 to 19 years, attack rates were lower among those ages 5 to 9 years, in whom 2-dose vaccination coverage rates were highest (P < 0.001). Early and rapid implementation of mass vaccination campaigns was significantly associated with shorter duration of outbreaks (P = 0.049). CONCLUSION: The measles outbreaks in Micronesia show that island populations may be highly susceptible to measles. High two-dose vaccination coverage levels must be maintained to prevent such outbreaks. Early and rapidly implemented mass measles vaccination campaigns were effective in control of island outbreaks. Strengthening public health infrastructure and surveillance is necessary for early identification of outbreaks and rapid implementation of mass campaigns.

Adolescent↗

PubMed1998

Diphtheria.

Explore the source record for details and available documents.

Child↗

PubMed1997

Risk of occupational exposure to potentially infectious nonhuman primate materials and to simian immunodeficiency virus.

Five hundred fifty persons who worked with nonhuman primates (NHP) or with NHP material in 13 North American research institutions were surveyed for potential occupational exposures and tested for antibodies to simian immunodeficiency virus (SIV). Needlesticks and mucocutaneous exposures were reported more frequently among persons who handled SIV-negative or SIV-status-unknown (SIV-N/U) animals (36% and 35%) or who worked with SIV-N/U material in the laboratory (18% and 17%) than among persons who handled SIV-positive NHP (SIV-P) (9% and 4%) or worked with SIV-P material (6% and 8%). The risk for needlesticks when working with both SIV-N/U and SIV-P animals and the risk for mucocutaneous exposures from SIV-N/U animals increased with the number of years working with NHP. Persons who performed invasive tasks (e.g., obtaining blood samples, performing surgery/autopsies) were more likely than others to sustain needlesticks (adjusted OR = 3.55, 95%CI = 1.40-9.02). Two (0.4%) of 550 persons had antibodies to SIV. One appears to be infected with SIV, as previously reported. These data suggest that persons who work with NHP or with NHP material are at risk for occupational exposure to potentially infectious materials including SIV. Prevention strategies are needed to reduce the risk for needlesticks and mucocutaneous exposures around all NHP, and safety guidelines should emphasize prevention options for invasive tasks performed with animals.

Animals↗

PubMed1996

An international collaborative study of the effects of coinfection with human T-lymphotropic virus type II on human immunodeficiency virus type 1 disease progression in injection drug users.

To determine whether human T-lymphotropic virus (HTLV) type II coinfection affects progression of human immunodeficiency virus type 1 (HIV) infection, longitudinal data on 370 HIV-infected injection drug users (IDUs) with known HIV seroconversion dates from four cohort studies were pooled. HTLV infection was determined by EIA and confirmed and typed by Western blot. Proportional hazards models were used to determine whether HTLV-II infection was associated with AIDS or AIDS-related mortality. Regression analyses were used to compare declines in CD4 cell percents in singly and dually infected persons. Of 370 IDUs, 61 (16%) were HTLV-II-coinfected. During follow-up, 43 (12%) developed and 24 (6%) died of AIDS. HTLV-II coinfection was not associated with progression to AIDS (relative hazard [RH], .82; 95% confidence interval [CI], 0.34-1.94]) or AIDS mortality (RH, 1.69; 95% CI, 0.62-4.60). Rates of decline in CD4 cell percent were similar in singly and dually infected IDUs. These results suggest that HTLV-II does not affect the progression of HIV infection.

Acquired Immunodeficiency Syndrome↗