Causes of cold in four-month-old babies

In fact, babies need careful care in all aspects of care, so that the baby's health can be guaranteed. Moreover, babies have particularly poor resistance and will catch a cold if they are not careful. So let us now understand the reasons why four-month-old babies catch a cold.

main reason:

The pathogens of colds are viruses. The most common ones include rhinovirus, coronavirus, influenza and parainfluenza viruses. Less common ones include respiratory syncytial virus, adenovirus, enterovirus, reovirus, herpes simplex virus and Epstein-Barr virus. Mycoplasma pneumoniae, group A, C, and G streptococci, and non-biological pathogenic factors such as allergic rhinitis, atrophic rhinitis, vasomotor rhinitis, deviated nasal septum, foreign bodies, etc. can all cause cold-like symptoms, which are not true colds.

1. Rhinovirus was isolated from a cold patient in 1956. It is a genus of the microRNA virus group. It is a non-enveloped single-stranded RNA virus with a diameter of 15 to 30 nm. It is resistant to ether but not acid (it is easily inactivated in a solution of pH 3) and can survive for 3 days in a dry environment. According to the serum neutralization test, there are more than 120 serum strains, which grow best in diploid cell culture at 33°C, can survive for a long time at -70°C, and can survive for several weeks at 4°C, but can be inactivated at 56°C for 30 minutes. 30% to 50% of colds are caused by a certain serotype of rhinovirus.

2. Coronavirus belongs to the coronavirus group. It is an enveloped single-stranded RNA virus that is sensitive to both ether and acid. The diameter is 80 to 150 nm, with unique rod-shaped peplomers protruding from the cyst, proliferating in the cytoplasm and maturing through budding from the cytoplasmic reticulum. At least three strains (B814, 229E and 0C43) can cause respiratory infections. Among them, 229E and OC43 are the causes of upper respiratory tract infections in children and adults, accounting for 15% to 20% of adult colds, and occasionally can cause pneumonia and epidemic chest pain.

3. Adenovirus is a non-enveloped, double-stranded DNA virus that replicates in the nucleus. It has a diameter of 70 to 90 nm and is a symmetrical icosahedron. It is relatively stable at low temperatures of -20°C. 41 serostrains have been isolated from humans, and there are still many intermediate strains. Clinically, it can manifest as various types of infection.

The above article gives you a detailed introduction to the reasons why four-month-old babies catch colds. I believe you already have a preliminary understanding of it. So in daily life, if your baby has a cold, you should go to the hospital for examination in time.