Whereas horizontal transmission of pathogens (germs) is between one cat to another both of whom are not in a parent to child relationship, vertical transmission is between mother and offspring as a foetus or kitten in utero.
For example, feline parvovirus can be spread vertically if the queen (mother cat) becomes infected whilst pregnant. The outcome of the infection depends on the stage of the pregnancy.
The infection can cause the birth of mummified kittens, underdevelopment of the cerebellum and poor coordination of the kittens due to cerebellar hypoplasia and abortion.
The feline leukemia virus and FIV can also be transmitted vertically.
Perhaps the most common feline diseases feline herpes virus which causes a cold in domestic cats. Research involving domestic cats has shown that feline herpes virus (FHV) is transmitted horizontally by close contact with body fluids from infected animals, such as nasal, ocular and oral secretions. Infections are common in animal shelters due to poor hygiene and close housing conditions which promote stress and which facilitate disease transmission.
Horizontal transmission can be from direct contact between cats such as when a part of a cat meets another cat or when a cat licks another cat or when fighting. Indirect horizontal transmission includes via bedding and feeding bowls (inanimate objects).
Airborne transmission of droplets produced when sneezing or coughing are particularly important in the spread of respiratory diseases. Some organisms can remain ‘alive’ for a long time in the environment especially in dark, damp conditions. Some ‘infectious agents’ need an intermediary for transmission from cat to cat. This applies to the tapeworm in which small rodents are the intermediate host and fleas the vector.
