The UK Department of Public Health (PHE) issued a warning on Monday for all residents of the country, after men contracted the disease.
Although "there is no risk" for the general public, the families of the victims, their friends and the medical staff present there are being monitored and will receive the vaccine if necessary, clearly the health agency.
Rabies, which is usually fatal when symptoms appear, is a contagious viral disease that affects the brain and central nervous system. Early manifestations include anxiety, headache and fever, which can cause hallucinations and respiratory failure, according to PHE.
This virus is transmitted to humans through animal bites or scratches and the first symptoms can occur between 3 and 12 weeks later.
No human has rabies in the UK for animals – other than bats – for more than 100 years, PHE reported. The agency added that the disease was not circulating in wild or domestic animals in the country.
However, five Britons contaminated rabies against animals abroad between 2000 and 2017.
PHE used the incident to remind its citizens of the risks when traveling abroad. "This is an important reminder of the precautions that people must take when traveling to countries where rabies is present," PHE immunization chief Mary Ramsay said in a statement.
"If an animal bites you, scratches you or licks you, you should wash the wound or place the exposure with lots of water and soap, and consult a doctor without delay," the health agency said.
If, after being exposed to animals with rabies, there is rapid treatment, the vaccine "is very effective in preventing disease," PHE said.
Geoffrey Smith, leader of the pathology department at the University of Cambridge, explained that rabies is one of several diseases in which vaccines can be effective after infection. "But this depends on how quickly it is done and also where the patient is bitten," he said.
"After a bite in the leg, there is more time to vaccinate before the virus reaches the brain through nerve cells, rather than if the wound is behind the neck."
Rabies occurs in more than 150 countries and regions throughout the world. Every year, more than 59,000 people die from rabies: the poor and disadvantaged are the ones most affected when there is limited access to medical care.
It is estimated that 95% of cases occur in Africa and Asia, according to the World Health Organization, with more than 99% of cases due to dog bites.
Smith also explained that not only dogs and cats are carriers of rabies. "Almost all mammals can be infected by the rabies virus and large reservoirs are bats," he said.