Disadvantages of keeping a dog

Many people like to keep cats and dogs at home, especially puppies are the favorite of many people. Raising a puppy can not only accompany the children at home and serve as their playmates when they are bored, but also serve as a personal bodyguard to guard the house. Dogs are not only one of the best pet choices, but also a good friend of mankind. It is also very easy to raise a dog, so many people like to keep a dog.

It should be said that if there is a dog at home, it can be quite lively indeed, but not everyone is suitable for raising a dog, especially for those who have children or pregnant women at home. So what are the disadvantages of raising a dog?

1 Toxoplasma infection

1.1 Pathogen and Epidemiology Toxoplasma gondii is a protozoan disease with cats as the definitive host and humans, pigs, cattle, sheep, horses, rabbits, dogs, etc. as intermediate hosts. After people ingest Toxoplasma oocysts or cysts, the trophozoites not only accumulate in the intestines, liver, and lungs, but also enter the lymph and blood and spread throughout the body, causing an acute infection. When the body's immunity begins to form (1 to 2 weeks after infection), cysts are formed in the nerves, retinal cells, myocardial and skeletal muscle cells. The cysts parasitize in the human body for months, years or even lifelong, presenting a latent chronic infection state. Domestic animals that have close relationships with humans, such as cats, dogs, pigs, and sheep, can all become sources of infection. Importantly, pregnant women can infect their fetuses through vertical transmission. The rate of intrauterine infection of the fetus is 0.5% to 1.0%. The incidence rate in our country is 4% to 9%.

1.2 Adverse effects on the fetus The extent of the impact of toxoplasmosis on the fetus during pregnancy is closely related to the period when the pregnant woman is infected with Toxoplasma gondii. Severe fetal damage often occurs in early pregnancy, and miscarriage often occurs〔1〕. When pregnant women are infected in the first 3 months of pregnancy, about 15% of the embryos are infected, about 25% in the 4th to 6th months, and about 60% in the 7th to 9th months. Infection in early pregnancy has serious effects on the embryo, which may cause stillbirth, miscarriage or congenital malformations. Infection in mid-to-late pregnancy is 90% latent infection, which may affect fetal development or congenital toxoplasmosis after birth. In addition to fetal developmental retardation, toxoplasmosis is mainly characterized by central nervous system symptoms, including toxoplasmic meningitis, hydrocephalus, brain calcification, microcephaly, in addition to chorioretinitis, cataracts, mental retardation, etc.

1.3 Diagnosis of toxoplasmosis Pregnant women can use clinical symptoms and laboratory tests such as staining tests, indirect fluorescent antibody assay (IFA), which can measure IFA-IgM and IFA-IgG respectively; enzyme-linked immunosorbent assay (ELISA), DNA hybridization test and pathogen examination to find the results of Toxoplasma gondii test, such as IgM (+), IgG (-) indicates early Toxoplasma infection; IgM (-), IgG (+) indicates recent Toxoplasma infection; IgM (-), IgG (+) indicates immunity; IgM (-), IgG (-) indicates no Toxoplasma infection and no immunity.

2 Rubella virus infection

2.1 Pathogen and Epidemiology Rubella virus (RV) is an irregular spherical virus with a size of 50 to 70 nanometers. The viral core is a positive-strand single-stranded ribonucleic acid (RNA) with one nucleocapsid protein (C) and three envelope proteins, all of which are antigenic to humans. RV can replicate in sensitive cytoplasm, can be inactivated at 56℃ for 30 minutes, can survive for a long time at -60℃, and can be easily inactivated by ultraviolet lipid solvents. People are generally susceptible to RV infection. The source of infection is rubella patients. The patient is contagious from 1 week before the rash to 5 days after the rash appears. Pregnant women can be infected through vertical transmission to the embryo or fetus.

2.2 Adverse effects on the fetus Congenital rubella infection often occurs when the mother is first infected, and the harm to the fetus after being infected with the rubella virus mainly depends on the gestational age. The relationship between the malformation rate of rubella and the gestational age is that the malformation rate of the fetus at 1 month of age is 33%, 2 months of age is 25%, 3 months of age is 9%, 4 months of age is 4%, and 5 months of age is 1%. It only occurs occasionally after that. Embryonic rubella formation defects must occur during a critical period of embryonic tissue division or differentiation, when embryonic tissues are selective and susceptible to RV infection. Organs such as the heart, central nervous system, eyes, and ears are infected and develop defects in the early embryonic stage, while the cerebellum is infected and develops defects in the late embryonic stage. RV infection can be primary infection or secondary infection. The initial infection is dangerous to the embryo and fetus and can cause inflammatory changes

And inhibit the proliferation and differentiation of fetal cells, resulting in maldevelopment of certain organs and congenital abnormalities, including patent ductus arteriosus, pulmonary artery stenosis, atrial septal defect, microphthalmia, cataracts, glaucoma, liver and spleen enlargement, and nervous system developmental disorders. Reinfection is generally not dangerous because the presence of antibodies makes viremia unlikely.

2.3 Antenatal diagnosis of RV intrauterine infection Infection during the embryonic period can only be diagnosed in pregnant women, but one-third of pregnant women with rubella do not show clinical symptoms, so serological diagnosis must be used. Serological diagnosis of rubella in pregnant women can be made by hemagglutination inhibition test (HI), complement fixation test (CF), enzyme-linked immunosorbent assay (ELISA) or radioimmunoassay (RIA) to measure the positive conversion rate of antibodies in the blood.

3 Herpes simplex virus infection

3.1 Pathogen and Epidemiology Herpes simplex virus (HSV) is round in shape, with a double-stranded linear DNA core and a three-layer shell structure on the outside. HSV has two serotypes, namely HSV-I type, which often infects the oral mucosa, upper body skin, and lymph nodes, accounting for 10%. It mainly causes herpes on the skin, mucous membranes or organs of the upper body, but rarely infects the fetus. HSV-II is genital herpes, accounting for 90%〔2〕. It mainly causes herpes on the genitals (labia, clitoris, cervix, etc.), anus and skin below the waist, and direct sexual transmission accounts for the vast majority. Infected pregnant women can transmit the virus directly to their fetus. HSV can be easily killed by ultraviolet radiation, lipid solvents, and common disinfectants. The sources of HSV infection are patients and carriers. After primary infection, a small number of viruses can remain latent for a long time and become latent infections. Pregnancy can cause HSV reactivation in the body of pregnant women and cause relapses. The incidence rate of pregnant women is 2 to 3 times that of non-pregnant women.

3.2 Adverse effects on the fetus: Herpes simplex infection of the embryo is rare, but the fetus can be infected through the placenta by the herpes virus in the uterus, resulting in miscarriage, premature birth, stillbirth and birth defects. Birth defects commonly include microcephaly, microphthalmia, chorioretinitis, etc. The HSV-II infection rate that can cause congenital infection is mainly in pregnant women, which is 3 times higher than that in non-pregnant women. Most neonatal HSV-II infections are caused by infection through the birth canal during delivery, but if it is transmitted through the placenta in utero, the consequences for the fetus are serious. It is currently recognized that cases of severe transplacental infection of the fetus are rare. Newborns infected through the birth canal show systemic disseminated infection, with a neonatal mortality rate as high as 70% to 80%. Most survivors suffer from central nervous system sequelae.

3.3 Diagnosis of HSV The main symptoms of HSV infection in pregnant women with reproductive organs are herpes, ulcers and pain on the cervix, vagina and external genitalia. The symptoms of infection in the birth canal in newborns are herpes in the eyes, skin or mouth. Symptoms of the central nervous system include lethargy, vomiting, fever, etc. In severe cases, the infection can spread to organs such as the liver, spleen, and adrenal glands. The laboratory mainly uses lesion specimens to isolate HSV serological diagnosis, enzyme-linked immunosorbent assay (ELISA), and measurement of specific IgM in the serum of newborns.

4 Cytomegalovirus infection

4.1 Pathogen and Epidemiology Cytomegalovirus (CMV) can only infect humans. The characteristic lesions of CMV infection are enlargement of infected cells and the presence of eosinophilic and alkalitropic inclusion bodies in the nucleus and cytoplasm, respectively. Cytomegalovirus has the biological characteristics of latent activity and is mostly latent infection, which can be activated by pregnancy. The replication cycle is about 36 to 48 hours. CMV at pH.

It should be said that raising a dog has its good side, but of course it also has its bad side, so before raising a dog it is best to make sure whether you can accept these shortcomings of the dog. Of course, it should be said that if you pay attention to some details in daily life, such as hygiene, then raising a dog is actually a very good choice.