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Diseases / Rabies


What is it?: 

Rabies is a viral zoonotic disease responsible for an estimated 59 000 human deaths and over 3.7 million disability-adjusted life years (DALYs) lost every year. Rabies is almost invariably fatal once clinical signs appear, as a result of acute progressive encephalitis.1

Most cases occur in Africa and Asia, with approximately 40% of cases in children aged <15 years. All mammals are susceptible to infection by the rabies virus (RABV). Transmission of RABV by dogs is responsible for up to 99% of human rabies cases in rabies-endemic regions, with a small proportion due to transmission via wildlife (such as foxes, wolves, jackals, bats, racoons, skunks or mongoose).1

Human-to-human transmission of rabies has never been confirmed, except extremely rarely as a result of infected tissue and organ transplantation1

Clinical features: 

The initial presentation of rabies may be nonspecific and include flu-like symptoms such as malaise, fever or headache, which may last for days. There may be numbness and tingling sensation around the wound. After a few days, anxiety, confusion, spasm of swallowing muscles, paralysis, coma and death will occur.2

Mode of transmission: 

When humans are bitten or scratched, or when their broken skin is licked by an infected animal, the virus in the saliva of the infected animal enters the human body through the wound and travels through nerves to the brain, leading to encephalitis. Rarely, rabies may also be transmitted by inhalation of virus-containing aerosol or via transplantation of an infected organ.2

Incubation period: 

The incubation period is usually 2 to 3 months, but may vary from less than 1 week to over 1 year.2

  1. Dog owners should make sure their dogs are licensed and vaccinated against rabies.2
  2. Avoid contact with stray animals, including dogs, cats and monkeys.2
  3. Pre-exposure or post-exposure immunisation, combined with thorough wound cleaning, is the most effective method of preventing rabies. After being bitten by animal, wash wound thoroughly with liquid soap and water immediately. Then seek medical attention at the nearest Accident and Emergency Department. If necessary, post-exposure immunisation may be given by the attending doctor.2
  4. Pre-exposure immunisation is recommended when travelling to high-risk destination for long-stay travellers, short-stay travellers to remote rural regions without medical facilities, or travellers with extensive outdoor exposure or engaging in high-risk activities (such as hiking, trekking, cycling, animal handling and visiting bat-infested caves). Please visit the website of Travel Health Service of the Department of Health for more details.2

Once symptoms of rabies appear, the disease is nearly always fatal, and treatment is supportive.2


  1. World Health Organization. Rabies vaccines: WHO position paper. Apr 2018.
  2. Centre for Health Protection. Communicable diseases – Rabies. 3 Dce 2019. [ONLINE] Accessed 8 Mar 2021.