Licensed books on medicine
<< Previous || Next >> |
INFECTIOUS (VIRUS) HEPATITIS CARNIVOR
Infectious carnivorous hepatitis (lat. - Hepatitis infectiosa carni-vorum; English - Infectious canine hepatitis; carnivorous hepatitis, Pyart's disease) - an acute contagious disease characterized by fever, catarrh of the mucous membrane of the respiratory and digestive tract, damage to the eye, liver and central nervous system.
Historical background, distribution, hazard and damage. The hepatitis virus was first isolated Green (1928) in the United States from silver-black foxes. In the USSR, this disease in foxes and arctic foxes was described by A.P. Kiru-Muratov (1932), I.G. Lebenberg (1937). In dogs, infectious hepatitis was studied by S. Rubart (1947). The disease is common in many countries - the USA, Japan, Sweden, Denmark, England, Turkey, Russia, etc.
The causative agent of the disease. The causative agent of hepatitis carnivores is a DNA-containing virus from the genus Mastadenovirus of the Adenoviridae family. By virulence, the strains are somewhat different, but in antigenic terms they are all homogeneous. Depending on the severity of tropism to liver or brain tissue, virus strains are divided into neuro- and hepatotropic. The virus is cultured in cultures of epithelial cells, causing a pronounced CPD in them with the formation of intranuclear Taurus inclusions.
Virions of the causative agent of hepatitis carnivores are located in the nuclei of cells. Their structure includes precipitating, hemagglutinating and complement binding antigens. All strains have the same group and specific complement-binding antigens.
The virus is resistant to various physical factors. When frozen, dried and in a 50% solution of glycerol at room temperature, the virus remains virulent for several years, in nature it can persist for more than 2 years. At a temperature of 4 ° C, the virus remains active for more than 9 months, at 37 ° C - up to 39 days, 50 ° C - 150 min, 60 ° C - 3 ... 5 min, 100 ° C - 1 min. The causative agent is resistant to ether, chloroform and methanol and is unstable to formalin, lysol, phenol, freshly slaked lime, which inactivate it for 30 minutes.
Epizootology. In vivo, dogs of all ages and breeds are susceptible to infectious hepatitis, but young animals aged 1.5 ... 6 months are more sensitive. Animals older than Zlet rarely get sick. Arctic foxes, foxes, wolves and jackals also get sick. Mice, monkeys, and humans can be hidden carriers of the carnivorous infectious hepatitis virus.
The main source of the causative agent of the infection are dogs, re-convalescents and virus carriers, in which the virus is excreted in urine, nasal mucus, conjunctival secretions and feces. A characteristic epizootological feature of infectious hepatitis in dogs is a prolonged virus carriage, which continues in animals for several years. Wild animals and stray dogs serve as a reservoir of the virus in nature. Infection occurs by alimentary and contact routes.
There is evidence that female virus carriers can infect their puppies and male males during mating for several years.
The disease usually manifests itself in the form of sporadic cases or epizootic outbreaks. In fresh epizootic foci, livestock coverage sometimes reaches 70%. Often the epizootic of infectious hepatitis is seasonal - in spring and summer when young animals appear. Sporadic cases of the disease are noted at any time of the year, and they are mainly associated with an exacerbation of the latent or chronic course of the disease under the influence of any adverse conditions.
When a disease occurs in dog nurseries, a certain sequence is observed in the development of an epizootic of infectious hepatitis. In the initial period of the epizootic process, isolated cases of acute illness are recorded. Subsequently, in the absence of the necessary veterinary and sanitary measures, epizootics spread more widely, covering a significant number of dogs in the first 2 ... 3 weeks and gradually fading by the end of the 2nd ... 3rd month.
Morbidity and mortality depend on contributing and disease-promoting factors. Mortality in infectious hepatitis among dogs reaches 20%. Often, hepatitis is accompanied by other infectious diseases: salmonellosis, plague, Escherichiosis, which leads to a sharp increase in animal death and complicates the differential diagnosis.
Pathogenesis. Once in the body, the virus multiplies first in the regional lymph nodes, then appears in the blood. After 2 ... 3 days, it forms a cluster in the form of intranuclear inclusions in the endothelial cells of capillaries and venules of all organs, especially the liver and spleen. As a result of damage to the central part of the liver lobules, dystrophic changes in the organ parenchyma develop, which leads to a profound metabolic disorder and intoxication of the body. Increasing intoxication leads to dystrophic changes in the kidneys, heart muscle and multiple hemorrhages in the mucous membranes and serous membranes, as well as in parenchymal organs.
After the virus enters the central nervous system, a violation of its regulatory function occurs, accompanied by locomotor disorders. During the period of pronounced clinical signs, the virus is in the blood, in all secrets and excretions, later - only in the kidneys and urine.
The course and clinical manifestation. With the natural infection of dogs with the infectious hepatitis virus, the incubation period lasts from 3 to 9 days, in fur animals - 10 ... 20 days.
Often there is an acute course of hepatitis. In a sick dog, depression, lethargy, refusal to feed, increased thirst, vomiting with an admixture of bile, unilateral or bilateral keratitis and tonsillitis are noted. The animal is less mobile, it lies more, it rises with difficulty, and its gait is shaky when moving. At the same time, body temperature rises, rhinitis, diarrhea develop, mucous membranes acquire icteric color. With pressure on the area of the liver, soreness is established. Convulsions and paralysis of the extremities often appear.
With an increase in body temperature, disorders of the cardiovascular system appear. The number of heart beats increases to 90 ... 110 in 1 min or more. The quality of the heart beat is enhanced, and the pulse in the severe course of the disease is weakened, sometimes arrhythmic. Rapid breathing - up to 40 ... 50 in 1 min. Wheezing is heard in the lungs.
A blood test reveals pronounced leukopenia at the beginning of the disease — 2 ... Ztys / μl [(2 ... 3) 109 / l] of leukocytes, then leukocytosis — up to 30 ... 35 thousand / μl [(30 ... 35) 109 / l]. The leukocyte formula during the infectious process almost always undergoes regular changes. In the early days, there is a relative increase in the proportion of neutrophils with the disappearance of eosinophils and a shift to the left to young, a decrease in the proportion of lymphocytes to 7 ... 15%, monocytosis. The toxic granularity of neutrophils is characteristic, in many animals plasma cells appear in the blood. In the acute period of the disease, ESR is significantly accelerated — up to 20 ... 30, less often up to 60 mm / h. Within 24 hours, ESR reaches 70 ... 80 mm / h. A decrease in the number of white blood cells and eosinophils, as well as a pronounced shift to the left are unfavorable indicators indicating a malignant course of the disease. Conversely, a sharp increase in the number of leukocytes and the restoration of the normal number of eosinophils indicate the recovery of the animal.
The duration of the disease in dogs is different - from several days to 2 ... 3 weeks. Animals perish, being in a deep coma, completely not responding to external stimuli.
In the chronic course of hepatitis in dogs, the symptoms of the disease are mild and undefined. The most commonly observed emaciation of the animal, relapsing fever, anemia of the mucous membranes, gastroenteritis, and swelling of the subcutaneous tissue.
Chronically ill females most often abort or bring non-viable puppies. Keratitis of one or both eyes is also noted for a long time.
The latent form of the disease is accompanied by the release of the virus without signs of the disease, but hepatitis can occur under the influence of adverse factors that reduce the body's resistance.
A distinctive feature of the disease in foxes is a permanent lesion of the central nervous system, manifested in the form of acute encephalitis with convulsions that turn into paralysis and coma. Seizures are usually short-lived - 3 ... 5 minutes, but occur several times a day. In the period between them, the animal is oppressed, moves slowly, and stumbles upon standing objects. Sometimes itchy skin is expressed, indigestion and keratitis are noted. Kills up to 50% of young animals and up to 10% of adult animals. Death occurs 2 ... 3 days after the onset of the disease.
Pathological signs. Changes in organs and tissues with infectious hepatitis are extremely diverse and depend on the duration and severity of the infection process.
During an external examination of the corpse, anemia of the mucous membranes, icteric staining and conjunctival hyperemia are noted. On anemic mucous membranes, especially on the gums, there are spot hemorrhages. Tonsils are often hyperemic, swollen. Changes in other organs (except the liver) are not strictly specific. A characteristic sign is hemorrhages of various localization.
The most typical changes are established in the liver. It is increased in volume, brown or dark red in color, with fibrinous plaque on the surface. The walls of the gallbladder are swollen. In most cases, a transparent yellowish or bloody exudate, in the form of pure blood, is found in the abdominal cavity.
A constant sign of infectious hepatitis is gelatinous edema and thymus congestion, in most cases with multiple
hemorrhages in it. The adjacent tissues are edematous, edema can spread to the neck, lower chest and mediastinum.
The spleen is often enlarged and full-blooded. Sometimes on the edges are foci of a heart attack. In the stomach, usually there is only mucus of a dark brown or almost black color. On the mucous membrane of the stomach hemorrhages, sometimes erosion, are possible. In the intestines, only minor changes are more often noted, but sometimes the mucous membrane of the thin and thick sections is thickened, covered with a large amount of mucus and multiple hemorrhages. The kidneys are in most cases enlarged, the capsule is easily removed. The parenchyma is pierced by point and banded hemorrhages. In the section, the figure is smoothed, the border between the cortical and cerebral layer is not expressed.
In the chronic course of the disease, anemia, exhaustion, and degenerative changes in the parenchymal organs in the form of granular protein and fatty degeneration are noted. In some cases, such changes are especially pronounced in the heart, liver, kidneys and sometimes in skeletal muscle. The liver is enlarged, compacted, with a peculiar pattern of muscularity, fatty degeneration is strongly expressed.
During histological examination, the most characteristic and permanent changes are found in the liver, especially in the central part of the lobules. Sinusoidal capillaries are dilated and filled with blood, in which there are many young red blood cells. At the same time, serous effusion in the Disse space is noted. Hepatic cells in a state of granular dystrophy and necrobiosis.
The presence of liver parenchyma, Kupffer cells and vascular endothelium of intranuclear Taurus inclusions (Rubart's body) is characteristic of infectious dog hepatitis. The most severe histological changes affect the endothelium of the cerebral vessels. Often note its proliferation, the presence of oblong Taurus inclusions, which create a picture of elongated nuclei with an edge standing chromatin.
Diagnostics and differential diagnostics. Infectious hepatitis is diagnosed based on an analysis of epizootological data, clinical signs, pathological changes, and laboratory tests for the presence of Rubart's bodies in smear smears or histological sections of the liver.
Intranuclear inclusions - Rubart's bodies, which are a homogeneous mass of a round or oval shape located in the center of the nucleus with an enlightenment zone around them, are found in smear imprints and histological sections. Chromatin and nucleoli are located on the periphery of the nucleus in the form of point clusters, painted in dark blue. Intranuclear inclusions are painted in bluish-reddish or pink color, clearly contrasting with the general background of the drug.
Currently, various serological and biological methods have also been successfully tested for laboratory diagnosis of hepatitis. Among them, the RDP has found wide application. This reaction is used for retrospective diagnosis of viral hepatitis, for the detection of a virus with known antisera, as well as for differential diagnosis.
In addition to RDP, in laboratory diagnosis of canine infectious hepatitis, RSK, RGA, RZHA, RIF, RN and bioassay are used by infecting puppies in the anterior chamber of the eye and isolating the virus in cell culture.
Infectious hepatitis in dogs must be differentiated from plague, leptospirosis, salmonellosis, and parvovirus enteritis in dogs. Crucial importance is given to laboratory research methods.
Immunity, specific prevention. In cases of hepatitis-infected animals, regardless of the severity of the transferred infection, a long-lasting, almost lifetime immunity is formed. Antibodies against the virus appear on the 15 ... 21st day after infection and reach a maximum on the 30th day.
Monovalent and associated inactivated vaccines and hyperimmune sera are used for specific prophylaxis. Vaccination creates immunity lasting up to 1 year.
Treatment. Polyvalent serum against the plague of carnivores, infectious hepatitis and parvovirus enteritis of dogs has high therapeutic efficacy at the onset of the disease. Of the symptomatic therapies, B vitamins, ascorbic acid, multivitamins, hepatoprotectors — Sirepar, Essential, Karsil, and others — have received the greatest use. For second infections, patients are prescribed antibacterial drugs.
Control measures. In the event of the occurrence of the disease, general veterinary-sanitary measures are carried out, the basis of which should be based on the principle of complexity: prevention of infection from outside; timely identification and isolation of patients; carrying out disinfection measures using a 10 ... 15% solution of freshly slaked lime or a 2% solution of sodium hydroxide, as well as other disinfectants widely used in veterinary practice.
In fur farms, in the event of the occurrence of infectious hepatitis, restrictions are introduced and prohibit the import, export, rearrangement, weighing, scoring, tattooing and animal exhibitions. Ill animals are kept in isolation and killed after maturation of the hairline. They carry out general sanitary measures to destroy the pathogen in the external environment. Restrictions are removed 30 days after the last case of recovery or death of the animal from hepatitis.
Control questions and tasks. 1. Describe the epizootological features of the disease. 2. What are the symptoms of the disease in various stages? 3. Describe the most characteristic pathological and histological changes. 4. What are laboratory diagnostics and differential diagnosis? 5. What is the treatment for carnivorous infectious hepatitis? 6. Describe prevention and control measures.
| << Previous || Next >> |
| = Skip to textbook content = |
INFECTIOUS (VIRUS) HEPATITIS CARNIVOR
- Infectious Carnivore Hepatitis
Carnivorous infectious hepatitis (hepatitis infectiosa) is an acute contagious viral disease characterized by fever, catarrh of the mucous membranes of the respiratory tract and intestines, damage to the liver, gall bladder and a violation of the central nervous system. Etiology. Pathogen DNA-containing virus of the Adenoviridae family, type I. Epithelial, neuro- and hepatotropic, can cause
- Question 14 Viral hepatitis
- inflammation of the liver tissue caused by viruses. Hepatitis viruses belong to different taxa and differ in biochemical and molecular characteristics, but all these viruses are united by the fact that they cause hepatitis in humans. Chronic liver diseases, including viral hepatitis B and C, are among the ten leading causes of death in the world. Currently, a large number of viruses are known.
- ACUTE VIRAL HEPATITIS
HBs are a big problem in childhood infectious diseases. Recent classifications distinguish 5 hepatotropic viruses that cause hepatitis B: A, B, D, C, E. These viruses, despite the fact that they belong to different taxonometric groups, cause a similar disease, the main manifestation of which is parenchymal hepatitis. The classification of acute HBV is based on the epidemiological principle, and
- VIRAL HEPATITIS DUCK
Ducklings viral hepatitis (lat. - Hepatits viriosa anaticularum; Duck virus hepatitis; infectious ducklings hepatitis, ducklings hepatitis, HHV) is an acute ducklings disease characterized by liver damage and high mortality, which occurs in adult ducks without symptoms. Historical background, distribution, hazard and damage. In 1949, in the USA, among the bred ducklings of Peking breed
- Viral hepatitis ducklings
Ducklings viral hepatitis (hepatitis viralis anatum) is an acute highly contagious disease of young ducklings, characterized by liver damage and nervous phenomena. Etiology. The causative agent of the disease is an RNA-containing, simply organized virus of the Picornaviridae family. The virus is easily cultivated on chicken, duck, goose embryos and in primary duck embryo cell cultures, with
- Viral hepatitis b
ETIOLOGY Hepatitis B virus. EPIDEMIOLOGY Infection of newborns from HBjAg-positive mothers occurs during or immediately after delivery. Transplacental transmission of the virus is rare. Если мать перенесла острый (симптоматический) гепатит в III триместре беременности или вскоре после родов, риск инфицирования плода намного больше, чем в тех случаях, когда заболевание пришлось
- Viral hepatitis ducklings
Это острая контагиозная болезнь, которая характеризуется поражением печени. К заболеванию восприимчивы утята преимущественно в возрасте 1-30 дней и реже — 40-60 дней. Взрослые утки, как правило, не болеют, но переболевшие вирусным гепатитом в молодом возрасте остаются до конца жизни вирусоносителями и вирусовыделителями. Возбудитель вирусного гепатита устойчив к высокой температуре. Находясь
- ИНФЕКЦИОННЫЙ ГЕПАТИТ (HEPATITIS INFECTIOSA)
Инфекционный гепатит - острая контагиозная вирусная болезнь, протекающая с лихорадкой, воспалительными процессами в дыхательных путях, желудочно-кишечном тракте, некротическими изменениями в паренхиматозных органах, особенно в печени. Etiology. Предположение о вирусной природе болезни впервые высказал в 30-х годах Каудри, а Рубарт подтвердил это экспериментально. Вирус проходит через
- вирусный гепатит В (клиника, диагностика, лечение)
Этиология: вирус гепатита В (ВГВ, HBV) - ДНК-овый гепаднавирус. Белок вирусной оболочки представлен поверхност-ным антигеном (HBsAg) - «австралийский» АГ, нуклеокапсид содержит сердцевинный (core) антиген (HBcAg), инфекционный (HBeAg), HBxAg, ДНК и ферменты (полимеразу и протеинкиназу). Каждый из антигенов ВГВ вызывает гуморальный иммунный ответ, проявляющийся выработкой соответствующих антител
- вирусный гепатит А (клиника, лабораторная диагностика, лечение)
Этиология: ВГА (семейства пикорнавирусов). Эпидемиология: источник инфекции - больной всеми формами острого инфекционного процесса (особое значение больные безжелтушными и бессимптомными формами). Механизм передачи: фекально-оральный, заражение происходит при употреблении инфицированной воды и пищи, иногда контактно-бытовым путем. Наибольшая восприимчивость к гепатиту А характерна для детей.
- LESSON 11 TOPIC. INFECTIOUS DISEASES. VIRAL INFECTIONS
Motivational characteristic of the topic. Knowledge of the topic materials is necessary for the assimilation of infectious diseases in clinical departments. In the doctor’s practical work, knowledge of the morphological manifestations of viral infections is necessary for the clinical and anatomical analysis of the manifestations of infectious diseases in sectional observations. The general purpose of the lesson. According to morphological characteristics, learn to identify the causes and
- Эпштейна—Барра вирусная инфекция (инфекционный мононуклеоз)
Инфекционный мононуклеоз — острое инфекционное заболевание, вызываемое вирусом Эпштейна—Барра из группы герпетиформных, характеризующееся лихорадочным состоянием, ангиной, увеличением лимфатических узлов, печени и селезенки, появлением атипичных мононуклеаров в периферической крови и гетерофильных антител. Etiology. Вирус по своей морфологической структуре не отличается от вируса простого