The National Institute of Communicable Diseases‘s most recent communique notes that there have been five confirmed cases of rabies in humans in South Africa to date in 2019 and also warns on differing strengths of equine rabies immunoglobulin issued for use in SA.
A probable case of rabies was reported in a four- year-old girl who died in May 2019. The patient was bitten by a stray dog on the face and leg in April 2019, in the Mbobeni-surrounds, Eastern Cape Province. The patient received four doses of rabies vaccine post-exposure, but rabies immunoglobulin was not given. The child was admitted to a hospital in KwaZulu-Natal Province where rabies was sus- pected. Ante-mortem testing for this child was not confirmatory. This could be expected in an immun- ised person, as the detection of virus in samples such as saliva become problematic. Post-mortem investigations were not possible for this case. Given the history of exposure to a stray dog prior to ill- ness, and a clinical history that is compatible with the diagnosis of rabies, this case was classified as a probable rabies case in the absence of laboratory confirmation.
The administration of rabies immunoglobulin is a critical life-saving therapy in individuals with cate- gory 3 rabies virus exposures. The product requires infiltration at the site of virus inoculation, i.e. the wound site or sites, for immediate virus neutralising effect. Rabies vaccination is provided in addition but may require 7-10 days for protective antibodies to be produced.
Important alert: Equine rabies immunoglobulin (ERIG) 1 500 IU/5ML has been authorised under section 21 of the Medicines and Related Substances Act, and will be issued for use in South Africa. This strength of rabies immunoglobulin differs from other stock of ERIG which may be available at facilities, which is ERIG 1 000 IU/5ML. Healthcare workers are advised to check the package insert of all ERIG products to ensure that the right dosage and vol- ume is administered. The recommended dose for ERIG is 40 IU/Kg.
Commenting on these rabies fatalities and cases, which were reported in the NICD’s latest Communicable Diseases Communiqué, Dr Pete Vincent of Netcare Travel Clinics and Medicross Tokai, said that they reiterate the importance of educating South Africans about this vaccine-preventable infectious disease, which is invariably fatal if it not managed and treated timeously and appropriately.
“If you consider that, according to the World Health Organisation (WHO), rabies is still responsible for close on 60,000 deaths globally every year, most of them occurring in Africa and Asia, then our track record of rabies prevention here in South Africa looks relatively impressive,” Vincent said.
“Nevertheless, the threat of rabies, which is contracted from infected animals, is ever present, particularly in our rural areas where many pet dogs are not vaccinated against the virus. In addition, rabies is quite commonly reported among both wild and domestic animals in South Africa.”
“Improved awareness of rabies – including knowledge of what to do in the case of a bite from, or contact with, a rabid animal such as a dog – will go a long way towards assisting in protecting South Africans and our children from rabies. It is important to be aware that a post-exposure prophylaxis vaccine and treatment is available to prevent the disease, but it must be administered appropriately and as soon as possible after exposure to rabies to be effective,” he adds.
“WHO reports that more than 15m people worldwide receive this life-saving post-exposure vaccination every year. This is an astonishing number and provides an indication of just how widespread the occurrence of rabies infection in humans is and how important this prophylaxis vaccine has become in preventing this infectious disease. A further important measure in controlling rabies, which attacks the nervous system, is the on-going mass vaccination of dogs, which are responsible for the great majority of infections in humans.”
“Another common misconception is that all animals infected with the virus become highly aggressive. In fact, there are two different strains of the virus, which can cause quite different symptoms, with some rabid animals becoming very docile rather than aggressive. So, if you are able to catch a mongoose, for example, then it is highly likely that it has rabies. Also be aware of bats as their bites can transmit rabies.
“One therefore needs to watch for any change in behaviour in an animal, rather than just aggression. Infected wild animals, for example, may lose their fear of humans and become easily approachable. People should stay away from stray dogs or any animal displaying strange and unusual behaviour.
“There needs to be greater awareness of rabies particularly in rural areas where it tends to be more common. Such education could assist people in identifying potentially rabid animals, staying away from them and alerting the relevant authorities,” Vincent said.NICD Communique