Patterns of Human Plague in Uganda, 2008-2016.

Plague is a highly virulent fleaborne zoonosis that occurs throughout many parts of the world; most suspected human cases are reported from resource-poor settings in sub-Saharan Africa. During 2008-2016, a combination of active surveillance and laboratory testing in the plague-endemic West Nile region of Uganda yielded 255 suspected human plague cases; approximately one third were laboratory confirmed by bacterial culture or serology. Although the mortality rate was 7% among suspected cases, it was 26% among persons with laboratory-confirmed plague. Reports of an unusual number of dead rats in a patient's village around the time of illness onset was significantly associated with laboratory confirmation of plague. This descriptive summary of human plague in Uganda highlights the episodic nature of the disease, as well as the potential that, even in endemic areas, illnesses of other etiologies might be being mistaken for plague.

[Analysis of diversity and identification of the genovariants of plague agent strains from Mongolian foci].

The genetic diversity of Yersinia pestis strains from the Mongolian natural plague foci has been investigated. A total of 32 strains isolated from western, eastern, and central aimaks, as well as from the territory of the Gobi region, have been studied. Twenty-four strains belong to the main Y. pestis subspecies, while eight belong to other subspecies. There is only one strain of biovar medievalis (genovariant 2.MED1) among the strains of the main subspecies, while the rest of the subspecies belong to the biovar antiqua. Biovar antiqua strains are split into three groups. Strains from the eastern part of the country were classified as genovariant 2.ANT3, and those from the western and central regions were classified as genovariant 3.ANT2, which was endemic for Mongolia. One strain from the Bayan-Ulegeiskii aimak had the rare genovariant 4.ANT. None of the strains of the biovar antiqua belonged to its ancient 0.ANT branch, which is inconsistent with the commonly accepted idea that ancient marmot's plague agent race originates from Mongolia. Six out of eight strains of the minor subspecies belonged to the ulegeica subspecies, which are endemic to Mongolia, one strain belonged to the microtus group, and the last belonged to a previously uncharacterized variant of the minor subspecies.

[Structural analysis of genes participating in melibiose fermentation and isocitrate lyase production in Yersinia pestis strains of main and non main subspecies].

Comparative analysis of nucleotide sequences of genes participating in melibiose fermentation and isocitrate lyase production was conducted in 90 natural Yersinia pestis strains of main and non main subspecies. It was ascertained that the lack of the ability to utilize disaccharide melibiose in strains of the main subspecies is caused by integration of the insertion sequence IS285 at 73 bp from the beginning of the structural gene melB that encodes the transport protein galactoside permease. In contrast, strains of non main subspecies (caucasica, altaica, and ulegeica) contain the intact gene melB and are capable of fermenting melibiose. Differences in the manifestation of the other differential trait, production of isocitrate lyase, are connected with the presence of mutation (insertion of two nucleotides +CC) in the regulatory gene iclR encoding repressor protein of the acetate operon, which is the reason for constitutive synthesis of this enzyme. Strains of non main subspecies do not contain mutations in gene iclR, and this correlates in these strains with their capacity for inducible synthesis of isocitrate lyase.

Pattern and spatial distribution of plague in Lushoto, north-eastern Tanzania.

A review of plague records from 1986 to 2002 and household interviews were carried out in the plague endemic villages to establish a pattern and spatial distribution of the disease in Lushoto district, Tanzania. Spatial data of households and village centres were collected and mapped using a hand held Global Positioning System and Geographical Information System. During the 16-year period, there were 6249 cases of plague of which 5302 (84.8%) were bubonic, 391 (6.3%) septicaemic, and 438 (7.0%) pneumonic forms. A total of 118 (1.9%) cases were not categorized. Females and individuals aged 7-18 years old were the most affected groups accounting for 54.4% (95% CI: 52.4-56.0) and 47.0% (95% CI: 45-49) of all reported cases, respectively. Most cases were found in villages at high altitudes (1700-1900m); and there was a decline in case fatality rate (CFR) in areas that experienced frequent outbreaks. Overall, there was a reduction in mean reporting time (from symptoms onset to admission) to an average of 1.35 days (95% CI: 1.30-1.40) over the years, although this remained high among adult patients (>18 years). Despite the decrease in the number of cases and CFR over the years, our findings indicate that Lushoto district experiences human plague epidemic every year; with areas at high altitudes being more prone to outbreaks. The continued presence of plague in this focus warrants further studies. Nonetheless, our findings provide a platform for development of an epidemic preparedness plan to contain future outbreaks.

[The plague in Madagascar: epidemiologic data from 1989 to 1995 and the national control program]. / La peste à Madagascar: données épidémiologiques de 1989 à 1995 et programme national de lutte.

After briefly reviewing the history and epidemiological cycle of the plague in Madagascar, we report a detailed analysis of 5,927 suspected cases of plague observed from 1989 to 1995 (average of 846 cases per year). Of those, 1,337 individuals (average of 191 cases per year) were confirmed (by isolation of Yersinia pestis) or indicated to be probable for plague (by positive smears). Since 1994, we observed an increasing number of confirmed and probable cases (252 cases in 1995). Most of the cases occurred between October and April in the central highlands, inside a geographical triangle limited by Alaotra lake, Itasy lake and the city of Fianarantsoa. Two exceptional epidemics occurred in the harbor of Majunga in 1991 and 1995. The bubonic plague was the most frequent clinical from (91.3%), with primarily an inguinal localization (67.8%). The mean case fatality rate was 19% of the confirmed or probable cases (14.8% for the bubonic form and 57.1% for the pneumonic form). The bubonic plague was significantly more frequent between the ages of 5 and 14 years, as compared to the general population, while the pneumonic plague was more frequent over 15 years of age. Males were more effected by the bubonic form, as the sex ratio (m:f) was 1.3. The national control program for plague is being strengthened to improve 1) the patient's early diagnosis and care system; 2) the measures for the prevention of epidemics; 3) the epidemiological surveillance; and 4) the studies on the biology of the plague vectors, rodents and fleas, and the agent, bacilli, in Madagascar.

[The epidemiologic classification of plague morbidity]. / Epidemiologicheskaia klassifikatsiia zabolevaemosti chumoi.

On the basis of the analysis of plague morbidity in the world in the XX century all epidemic foci are subdivided into 3 groups: primary, indirect primary and secondary. Each group is characterized by its specific type of morbidity in accordance with infective factors: factors connected with the natural foci of infection in group 1, economic and synanthropic factors, as well as laboratory infections, in group 2 and anthroponotic factors in group 3. In its turn, each type of morbidity differs in routes, sources, mechanisms and clinical forms of infection. In accordance with the conditions of infection, the natural foci of plague can be subdivided into mono-, oligo- and multifactor foci. The typing of plague morbidity facilitates more target-oriented organization of antiplague measures.

Radiographic manifestations of plaque in New Mexico, 1975-1980. A review of 42 proved cases.

The radiographic findings in 42 proved cases of plague are examined. There was a high association between bilateral alveolar infiltrates and secondary pneumonic plague; however, these findings were not completely specific, as they were also seen in some patients who had disseminated intravascular coagulation or shock lung, In an endemic area and in the proper clinical setting, any patient with bilateral alveolar infiltrates should be considered to have secondary pneumonic plague until proved otherwise.