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M V Szczeniowski

Publications and source records attributed to M V Szczeniowski.

6 recordsLinked to original sources

A search for Ebola virus in animals in the Democratic Republic of the Congo and Cameroon: ecologic, virologic, and serologic surveys, 1979-1980. Ebola Virus Study Teams.

More than 30 years after the first outbreak of Marburg virus disease in Germany and Yugoslavia and 20 years after Ebola hemorrhagic fever first occurred in central Africa, the natural history of filoviruses remains unknown. In 1979 and 1980, animals in the Democratic Republic of the Congo and Cameroon were collected during the dry season near the site of the 1976 Ebola hemorrhagic fever epidemic. The study objectives were to identify local animals and search for evidence of Ebola virus in their tissues. A total of 1664 animals representing 117 species was collected, including >400 bats and 500 rodents. Vero and CV-1 cells and IFA and RIA were used for virus and antibody detection, respectively. No evidence of Ebola virus infection was found. This study was limited in time and animal collections and excluded insects and plants. Long-term, prospective, multidisciplinary comparative studies will yield more information than will repeat short forays on the ecology of filoviruses.

Animals↗

Human monkeypox: disease pattern, incidence and attack rates in a rural area of northern Zaire.

Human monkeypox is a zoonosis that occurs sporadically in the tropical rainforest of western and central Africa. This article presents the results of epidemiological features of 91 monkeypox patients reported in Bumba zone in northern Zaire during the period 1981 to 1985. Their age ranged from 7 months to 29 years (93% below 15 years of age). 11% of patients had visible smallpox vaccination scars. Deaths occurred sporadically; the overall case-fatality rate was 9%. 91 patients arose in 61 separate outbreaks; 42 of them consisted of only a single case. The source of infection was suspected to be animal for 70 cases, and human for the remaining 21 cases. The illness occurred in all months of the year. There was a considerable clustering of cases in the northern part of the zone. The average annual incidence rate in the observed zone was 0.63 cases per 10,000 population with marked differences in age, time and place. The average annual primary attack rate among unvaccinated individuals (1.7/10,000) sharply contrasted with those vaccinated (0.04/10,000). The secondary attack rate for contacts without vaccination scar (4.3%) differed significantly from those who had been vaccinated in past (0.7%). Many unvaccinated contacts living under conditions of maximal exposure to index cases escaped not only the disease but also infection. The low incidence rate of human monkeypox indicates its limited public health importance even in a well-known enzootic area.

Adolescent↗

Human monkeypox: secondary attack rates.

Data on human monkeypox collected in Zaire during the six years 1981-86 were analysed to assess the extent of interhuman transmission of monkeypox virus. Among the 2278 persons who had close contact with 245 monkeypox patients infected from an animal source, 93 fell ill and were presumed to have been infected from the known human source: 69 of these were spread in the first generation, 19 in the second generation, and the remaining five cases in the third and fourth generation.The secondary attack rates were correlated with the age, sex, place of residence, and vaccination status of the contacts. There was an overall 3% probability of becoming ill following infection from a known human source. The affected household was the main focal point for interhuman transmission of monkeypox virus. The highest attack rate (11.7%) occurred among unvaccinated household contacts in the age group 0-4 years. However, the majority of susceptible persons who had been close to patients in the confined space of poorly ventilated huts failed to develop illness. There was no evidence of an increase in the secondary attack rate between 1970-80 and 1981-86.The inefficient spread from person to person, even in conditions of maximum exposure, supports the concept that monkeypox virus is poorly adapted for sustained transmission between humans and that such transmission does not pose a significant health problem.

Adolescent↗

[Human monkey pox: its clinico-epidemiological characteristics].

During the course of the smallpox eradication programme, a new eruptive disease clinically resembling smallpox was discovered in Zaire. The disease, which was named monkeypox after the virus, is a zoonosis occurring sporadically in countries of western and central Africa with tropical rain forest. The studies carried out in Zaire from 1980 through 1985 showed that monkeypox affects mainly children in relatively small remote villages whose population has traditionally frequent contacts with wild animals. Apart from the wildlife, the virus can be transmitted from man to man, but among other sources of infection sick persons did not exceed 20%. Presumed human transmission has occurred in 38 out of 61 outbreaks of human monkeypox and only once reached the third and once the fourth generation; the transmission in all affected villages under observation has extinguished itself. Considering the sporadic and relatively rare occurrence of the disease and expected complications following the immunization with vaccinia which protects from monkeypox, introduction of mass vaccination in the areas at risk is hardly justified at present.

Africa, Central↗

Human monkeypox.

Human monkeypox, occurring in the tropical rainforest of west and central Africa, is regarded as the most important orthopoxvirus infection for epidemiological surveillance during the post-smallpox era. This disease, first recognized in Zaïre in 1970 resembles smallpox clinically but differs epidemiologically. Clinical features, their evolution and sequelae of monkeypox could be compared with discrete ordinary or modified type of smallpox. A case-fatality rate of 14% has been observed but some cases can be exceedingly mild or atypical and may easily remain undetected and unreported. Pronounced lymphadenopathy has been the only clinical feature found commonly in monkeypox but not in smallpox. Fifty-seven cases of human monkeypox have occurred since 1970, in the tropical rainforests in six west and central African countries, the majority of them (45) being reported from Zaïre. The disease appears to be more frequent in dry season. Children below ten years of age comprise 84% of the cases. Smallpox vaccination protects against monkeypox. Clusters of cases have been observed in certain areas within countries and within affected households. Human-to-human spread has possibly occurred seven times. No cases of possible tertiary spread were observed. The secondary attack rate among susceptible close household contacts was 10%, among all susceptible contacts 5%. This is much lower than that occurring with smallpox, which is between 25-40%. The limited avidity of monkeypox virus for human beings indicates that monkeypox is probably a zoonosis, although the animal reservoir(s) have not yet been identified. The low transmissibility, resulting in low frequency of disease in man indicates that monkeypox is not a public health problem. Human monkeypox has been a relatively newly recognized disease. Studies are in progress to identify the natural cycle of monkeypox virus and to define better its clinical and epidemiological characteristics. Special surveillance is maintained in endemic areas with the aim to provide assurance that in spite of waning immunity of the human population following cessation of the smallpox vaccination, the disease does not constitute a potential danger to man.

Adolescent↗

Outbreak of human monkeypox, Democratic Republic of Congo, 1996 to 1997.

Human monkeypox is a zoonotic smallpox-like disease caused by an orthopoxvirus of interhuman transmissibility too low to sustain spread in susceptible populations. In February 1997, 88 cases of febrile pustular rash were identified for the previous 12 months in 12 villages of the Katako-Kombe Health Zone, Democratic Republic of Congo (attack rate = 22 per 1,000; case-fatality rate = 3.7%). Seven were active cases confirmed by virus isolation. Orthopoxvirus- neutralizing antibodies were detected in 54% of 72 patients who provided serum and 25% of 59 wild-caught animals, mainly squirrels. Hemagglutination-inhibition assays and Western blotting detected antibodies in 68% and 73% of patients, respectively. Vaccinia vaccination, which protects against monkeypox, ceased by 1983 after global smallpox eradication, leading to an increase in the proportion of susceptible people.

Adolescent↗