Russian Journal of Infection and ImmunityRussian Journal of Infection and ImmunityИнфекция и иммунитет2220-76192313-7398SPb RAACI198810.15789/2220-7619-LIV-1988REVIEWSОБЗОРЫReview ArticleLeptospirosis in VietnamЛептоспироз во ВьетнамеTokarevichN. K.ТокаревичНиколай Константинович
Russian Federation

PhD, MD (Medicine), Professor, Head of the Laboratory of Zoonoses

д.м.н., профессор, зав. лабораторией зооантропонозных инфекций

zoonoses@mail.ruBlinovaO. V.БлиноваОльга Владимировна
Russian Federation

PhD (Chemistry), Junior Researcher, Laboratory of Zoonoses

к.х.н., младший научный сотрудник лаборатории зооантропонозных инфекций

zoonoses@mail.ruSt. Petersburg Pasteur InstituteФБУН НИИ эпидемиологии и микробиологии имени Пастера3110202230122022126101910282206202223082022Copyright ©; 2022, Tokarevich N.K., Blinova O.V.Copyright ©; 2022, Токаревич Н.К., Блинова О.В.2022Tokarevich N.K., Blinova O.V.Токаревич Н.К., Блинова О.В.https://creativecommons.org/licenses/by/4.0https://iimmun.ru/iimm/article/view/1988

Leptospirosis poses a serious public health problem in many countries because about 1 million people suffer annually from this severe, often fatal, infection. At present, its importance has been increasing due to development of integration processes, globalization and intensification of economic activities, inevitable anthropogenic transformation of landscapes as well as rise in number of people with occupational risk of pathogen exposure. The burden of human leptospirosis is expected to rise with demographic shifts and climate change that result in heavy rainfall and flooding. Regarding leptospirosis, Southeast Asia, including Vietnam, is among the most vulnerable global regions. The objective of the review was to analyze available published data on the spread of leptospirosis in Vietnam. More than 100 research articles were analyzed allowing to state that in Vietnam synanthropic rodents (rats), agricultural (buffaloes, cattle, pigs) and domestic animals (cats, dogs) are the main sources of leptospirosis infection in humans. It is essential that rats (cats and dogs also) in Vietnam are used for food. Among all farm animals, pigs are of maximal importance as a source of infection in humans. In Vietnam, Leptospira prevalence in pigs varies widely, up to 73%. It depends significantly on the location, farm size, age and gender of animals, etc. A large variety of Leptospira serovars have been identified in pigs in Vietnam: Tarassovi, Bratislava, Australis, Javanica, Autumnalis, Grippotyphosa, and some others. Official Vietnam reporting of leptospirosis cases based on clinical data does not reflect the real-life incidence rate in humans. However, the available seroprevalence studies reveal that, on average, about 10% of the Vietnamese population are infected with Leptospira. Work in agriculture is the dominant risk factor for acquiring this infection. The highest Leptospira seroprevalence rates were detected in farmers, 63.2%. Serovar diversity is typical for pathogenic Leptospira circulating in Vietnam. In humans, the most frequent are antibodies to Hebdomadis, Wolffi and Icterohaemorrhagiae, but the frequency varied markedly across the country depending on the site, possibly with relation to the environment, as well as with economic activity of the local population. In Vietnam, geographic, climatic and social differences between northern, central and southern regions contribute to the specificity of local leptospirosis epidemiology. This emphasizes the advisability of developing special measures for leptospirosis prevention taking into account regional peculiarities.

Лептоспироз представляет серьезную проблему для здравоохранения многих стран, так как в мире ежегодно около 1 млн людей болеют этой тяжелой инфекцией, часто оканчивающейся летальным исходом. В настоящее время значение этой проблемы возрастает, что связано с развитием интеграционных процессов, обусловленных глобализацией экономики, интенсификацией хозяйственной деятельности, приводящей к антропогенной трансформации ландшафтов и расширению контингента лиц, входящих в угрожаемые профессии, а также глобальными климатическими изменениями. Юго-Восточная Азия, включая Вьетнам, относится к числу самых неблагополучных в отношении лептоспироза регионов мира. Целью работы является современный анализ литературных данных о распространении лептоспирозной инфекции во Вьетнаме. В ходе данной работы было проанализировано более 100 научных статей. Это позволило констатировать, что основными источниками лептоспирозной инфекции во Вьетнаме являются синантропные грызуны (крысы), сельскохозяйственные (буйволы, крупный рогатый скот, свиньи) и домашние (кошки и собаки) животные. Существенной особенностью заражения жителей Вьетнама является употребление ими в пищу крыс, кошек и собак. Из сельскохозяйственных животных в качестве источника инфекции наибольшее значение имеют свиньи. Показатели инфицированности этих животных лептоспирами колеблются в широких пределах, достигая 73%. Значение этих показателей существенно различаются в зависимости от территории обитания животных, от размера фермы, возраста, пола свиней, от количество осадков и ряда других факторов. У свиней во Вьетнаме было выявлено большое разнообразие сероваров лептоспир среди которых преобладали Tarassovi, Bratislava, Australis, Javanica, Autumnalis, Grippotyphosa и другие. Официальная отчетность о заболеваниях лептоспирозом, основанная на клинических данных, не отражает реальное количество больных во Вьетнаме. В среднем около 10% жителей Вьетнама инфицировано лептоспирами. Работа в сельском хозяйстве является доминирующим фактором риска заражения. Наиболее высокие показатели серопревалентности к лептоспирам были выявлены у фермеров — 63,2%. Для Вьетнама характерно большое разнообразие сероваров циркулирующих лептоспир. Наиболее часто у людей выявляются антитела к лептоспирам сероваров Hebdomadis, Wolffi и Icterohaemorrhagiae, но частота их встречаемости существенно различалась между собой в разных регионах, что, можно полагать, связано с ландшафтно-климатическим своеобразием территории, а также обусловлено хозяйственной деятельностью людей. Географические, климатические и социальные различия северной, центральной и южной части Вьетнама в значительной степени определяют эпидемиологические особенности лептоспироза. Это усиливает целесообразность разработки конкретных мер профилактики этой инфекции для каждой территории с учетом их специфики.

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