A case of cholera in Kingston,Ont.

A case of cholera occurred in Kingston, Ont. in 1974 in a traveller from South Africa. Treatment, based on an understanding of the pathophysiology of cholera diarrhea and the mechanism of action of the Vibrio cholerae enterotoxin on gastrointestinal fluid loss, consisted of correcting the severe loss of fluid and electrolytes and the metabolic acidosis, as soon as the patient could tolerate taking fluids orally, further fluid replacement consisted increasingly of oral administration of glucose and saline. Tetracycline therapy was given only to shorten the duration of the acute illness.     

Outbreaks of avian cholera in Hope Bay, Antarctica

During austral summers 1999-2000 and 2000-01, two outbreaks of avian cholera occurred in the Hope Bay area (63 degrees 24'S, 56 degrees 59'W), located on the tip of the Antarctic Peninsula. Eighty-six dead birds were found: five kelp gulls (Larus dominicanus), 36 skuas (Stercorarius sp.), and 45 Adelie penguins (Pygoscelis adeliae). The carcasses were studied using clinical, pathological, and microbiological criteria. Water samples from ponds where birds were settled and samples from 90 healthy birds also were analyzed during the second outbreak. Pasteurella multocida isolates were identified by biochemical tests, capsular type, somatic serotype, and susceptibility to nine antibiotics. Molecular subtyping was performed by ApaI and SmaI pulsed-field gel electrophoresis (PFGE) and enterobacterial repetitive intergenic consensus (ERIC-PCR). In February 2000, mortality in skuas was 16% and 2% in kelp gulls. In the 2000-01 breeding season, mortality in south polar skuas was 47%, 24% in brown skuas, 1.4% in kelp gulls, and 0.01% in Adelie penguins. All birds had lesions of avian cholera. In kelp gulls the presentation was chronic, whereas skuas and penguins suffered subacute and acute disease, respectively. Fifty-five isolates recovered from dead birds and one from water were identified as P. multocida gallicida, type A:1. The strains presented a unique molecular pattern by PFGE and ERIC-PCR. A possible hypothesis to explain the origin of the outbreaks was that nonbreeder kelp gulls carried P. multocida gallicida to Hope Bay, and avian cholera was transmitted through water to skuas and penguins. This study reports avian cholera in new bird species, their potential role in the transmission of the disease, and the different responses of these species to the disease.     

Avian cholera in waterfowl in Saskatchewan, spring 1977.

Avian cholera was diagnosed in lesser snow geese (Anser c. caerulescens), Ross' geese (Anser rossii) and individuals of several other waterfowl species in a small area of south-western Saskatchewan over a 1 month period during the 1977 spring migration. Approximately 250 dead birds were found. This is apparently the first time avian cholera has been reported in migrating waterfowl in Canada. The site of the mortality was midway between the wintering and nesting areas of the two principal species, and the significance of the occurrence of the disease this far north is discussed.     

The cholera epidemics and the development of public health in Meiji Japan. 1. Modernity, cholera, and health thought

We present here the beginnings of public health politics in Meiji Japan (1868-1912). Due to a two century isolation of Japan, public health concepts developed in the West from the end of the 18th century were foreign in premodern Japan. Due to its isolation, Japan was also relatively preserved from some acute infectious diseases such as cholera. In this paper, we investigate the role of cholera epidemics in the emergence of public health concepts in the peculiar context of Meiji Japan. We show that chronic diseases such as tuberculosis and leprosy were neglected for a long time and that the Meiji government set priority on acute infectious diseases that were considered as long as they disturbed public order. Nevertheless, some physicians and government officials considered issues of welfare and poverty. We also review some emerging concepts of social medicine. We try to show, that in Japan as well as in Western nations, public health politics were not exempt of contradictions and paradoxes and a permanent tension existed between coercitive policies and conceptions of welfare and rights to health.     

Serotype cycles in cholera dynamics

Interest in understanding strain diversity and its impact on disease dynamics has grown over the past decade. Theoretical disease models of several co-circulating strains indicate that incomplete cross-immunity generates conditions for strain-cycling behaviour at the population level. However, there have been no quantitative analyses of disease time-series that are clear examples of theoretically expected strain cycling. Here, we analyse a 40-year (1966-2005) cholera time-series from Bangladesh to determine whether patterns evident in these data are compatible with serotype-cycling behaviour. A mathematical two-serotype model is capable of explaining the oscillations in case patterns when cross-immunity between the two serotypes, Inaba and Ogawa, is high. Further support that cholera's serotype-cycling arises from population-level immunity patterns is provided by calculations of time-varying effective reproductive rates. These results shed light on historically observed serotype dominance shifts and have important implications for cholera early warning systems.     

Apudocytes in experimental cholera vaccination

The morphofunctional state of apudocytes in the gastrointestinal tract and immunocompetent organs (spleen, mesenteric lymph nodes) of mice immunized with chemical bivalent cholera vaccine was studied. The study revealed that the APUD system of the intestine and the argyrophil elements of the immunocompetent organs of white mice gave a response to the oral administration of commercial cholera vaccine. The reaction of the APUD system of the gastrointestinal tract was manifested by a significant increase in the number of apudocytes and their greater synthesizing activity in the immunized animals during the period of maximum immunological transformation of the macroorganism. The immunization of mice with Vibrio cholerae facilitated the maintenance of homeostasis in the macroorganism and prevented appearance of morphological disturbances in its organs and system after subsequent challenge with V. cholerae.     

Eltor cholera in Latin America

Cholera epidemics in South and Central America in the period 1991-1999 are characterized. The mechanisms of existence of Vibrio eltor in environmental objects have been substantiated. The causes and conditions of endemic foci formation which determine the infection spread not only within the countries of the subcontinent, but also far beyond its borders are shown. The effectiveness of cholera control interventions is evaluated.     

Role of neuraminidase from cholera vibrions in the pathogenesis of experimental cholera]

A study was made of a possible effect of neuraminidase of cholera vibrios on cholera pathogenesis. It was shown that in intraintestinal injection of cholera vibrios of the El Tor biotype to nursling rabbits neuraminidase could be revealed in their intestine 5 to 8 hours after the infection. Addition of neuraminidase to the weakly cholerogenic strain cholera vibrios intensified its cholerogenic action in infection of the animals. The antineuraminidase serum administered to the infected rabbits prevented clinical manifestations of experimental cholera, although it failed to always eliminate the cholerogenic syndrome (revealed during autopsy). At the same time neuraminidase did not influence the capacity of cholerogen to produce the cholerogenic syndrome. The authors consider that the action of the enzyme should occur at the early stages of the pathogenic process, and could be associated with creation of conditions for the attachement of cholera causative agent to the intestinal wall or for the action of their exotoxin.     

霍乱疫苗中残余霍乱毒素检测方法的建立及验证

采用间接酶联免疫法,即用神经节苷脂包被,加入待检样品,再加入兔抗霍乱毒素B亚单位抗体,用标准样品的吸光值(A值)对标准样品的浓度绘制4-参数拟合曲线,根据标准曲线计算出待测样品中的CT浓度。结果显示,在浓度范围(0.6～16)ng/ml之间,CT标准浓度和检测浓度成线性关系,r2=0.9986。精确度在浓度范围(0.6～16)ng/ml,CT的平均回收率在96.24%～114.44%之间。精密度:批内变异CV%≤12.98%,批间变异CV%≤18.48%。特异性CT浓度在10ng/ml时,平均回收率为102.6%;CT浓度在5ng/ml时,平均回收率为111.17%;CT浓度在2.5ng/ml时,平均回收率为123.83%。实验表明该方法可检测霍乱疫苗原液中CT的含量。