Generally speaking, Hong Kong is a relatively safe place for cats and dogs. However, owners should also be aware of some common and dangerous pet diseases in Hong Kong, such as tick fever.
cattle tick fever
Tick fever is very common in Hong Kong. It's somewhat similar to malaria, as ticks inject the babesia parasite into dogs through bites. Common symptoms include anemia, pale gums, fatigue, shortness of breath, and very dark urine.
There is currently no vaccine to prevent tick fever, but it is treatable; however, it can be life-threatening if not treated promptly. Tick fever rarely affects cats or humans, but mostly affects dogs.

Leptospirosis
Leptospirosis is uncommon in Hong Kong, but it is a very dangerous infectious disease. Dogs are highly susceptible to leptospirosis when they drink contaminated stagnant water, stagnant pond water, or river water from the street. Leptospirosis is a bacterial infection that can cause serious damage to internal organs. Although leptospirosis is treatable, the mortality rate is extremely high. Currently, there are not many cases of leptospirosis in Hong Kong, with most infections concentrated in the Peak and Mid-Levels areas. Vaccination against leptospirosis does not guarantee complete immunity in pets, but it can significantly reduce the risk of infection.
In Hong Kong, dogs are typically vaccinated annually with G6 or C5 vaccines to prevent canine distemper, hepatitis, parvovirus, etc., as well as leptospirosis and heartworm prevention. They also receive a rabies booster every three years and have their dog tags renewed.

heatstroke
In the sweltering summer heat, the chances of dogs suffering from heatstroke while out for walks are very high. Owners should remember to prevent heatstroke by stopping every 15 minutes to let their dogs drink water; owners can also sprinkle some cool water on their dogs' backs to help cool them down. Symptoms of heatstroke include panting, confusion, unsteady gait, loss of balance, and even blood in the urine. If you suspect your pet has heatstroke, immediately stop all activity, sprinkle cool water on your dog to try and cool it down, and then immediately take it to a veterinary clinic. If it's just mild heatstroke, the dog can rest at home, but if the owner has any concerns, they should seek veterinary assistance as soon as possible.
Fortunately, the risks to cats in Hong Kong are not too high. Since most cats live indoors, they encounter fewer risks than typical stray cats. Cats need to receive the F3 vaccine annually to prevent feline influenza and feline panleukopenia (FPL) , and they also need regular deworming. Feline leukemia and feline infectious disease ( FIV ) are relatively rare in Hong Kong, so owners can choose not to vaccinate their indoor cats against these diseases.