No 5 - 2012

Rabies prophylaxis

In connection with animal bites acquired in Denmark, bat bites are usually the only indication for prophylactic rabies treatment. In case of substantiated suspicion following other animal bites, the animal should first be examined by a veterinary that, if necessary, will destroy the animal and arrange further rabies investigation.

In other parts of the world, rabies is more widespread. Transmission occurs through the penetrating bite of an animal infected with rabies or - on rare occasions – results from direct contact between infected saliva and mucous membranes or wounds.
Prophylactic treatment after possible exposure should be discussed with the Department of Epidemiology, where human rabies immunoglobulin (HRIG) and vaccine may be ordered by general practitioners at the expense of the National Health Service.
Pre- and post-exposure prophylaxis recommendations, EPI-NEWS 37/10.

Post-exposure prophylaxis

In 2010 a total of 150 patients received prophylactic rabies treatment following animal bites, Table 1.
A total of 80 persons were treated with HRIG in addition to vaccination.

Ten persons were given prophylactic treatment because of bat bites in Denmark, and two bats were tested for rabies.
One person in Denmark was bitten by a dog imported from Greece, and another was bitten by a sheep presenting with neurological symptoms.

As bat rabies was previously detected in a limited number of Danish sheep, EPI-NEWS 24/03, the four affected sheep were tested. All sheep tested negative for rabies virus and treatment was terminated.

Furthermore, 92 Danes were exposed to rabies in Asia (including 54 in Thailand and seven on Bali), 36 in other European countries (including 26 in Turkey), five in Africa and five in Central and South America. Among the 54 persons treated following possible rabies exposure in Thailand, 28 were bitten by dogs, 23 by monkeys/apes and three by cats.

Commentary

Possible exposure to rabies abroad was the primary cause of post-exposure prophylaxis, as 92% of all treated cases had travelled abroad, including 40% to Thailand.
The increasing trend in the number of persons who receive prophylactic treatment following animal bites in Thailand continues, EPI-NEWS 4/11. The increase in the number of post-exposure treatment following animal bites abroad is probably due to a combination of growing awareness and increased travel activity.

When giving advice prior to foreign travel, it is important to mention the risk of rabies associated with contact to animals. Travellers should be advised to limit contact to animals and to see a physician without delay in case of a bite.
(A.H. Christiansen, S. Cowan, Department of Epidemiology)

Rabies in animals

Since 1982, Denmark has been free of classic rabies virus, whereas infection with such type is endemic in Greenland, where arctic foxes frequently transmit the infection to sled dogs and other mammals.

In 2011, classic rabies virus was detected in a sheep from Greenland, Table 2.
Bats are a reservoir for EBLV (European Bat Lyssavirus). EBLV was initially detected in bats in Denmark in 1985, and the most recent positive finding occurred in 2009.

Rabies outbreak on the islands of Svalbard

The autumn of 2011 saw a rabies outbreak on the Norwegian islands of Svalbard following more than ten years with no cases of the disease.
In September, two Arctic foxes tested positive to classic rabies virus, and subsequently eight reindeer has been diagnosed with the disease. Due to the outbreak, about 300 persons have received post-exposure prophylaxis. The Norwegian authorities have initiated a range of measures with a view to controlling the outbreak. No numan cases have been observed.

(T. B. Rasmussen, National Veterinary Institute, Technical University of Denmark, Lindholm)

Theme day: Copenhagen rainstorm 2 July 2011

On 26 January, the Central Infectious Hygiene Unit (CIHU) and the Department of Epidemiology held a status meeting covering the inundations following the Copenhagen rainstorm on 2 July 2011. About 60 persons participated, including healthcare professionals, water experts and companies who had answered a questionnaire. The rainstorm was extraordinarily heavy, but the foreseen climate changes carry a risk of similar inundations in future.
The problem associated with large amounts of rain water is that it may overload the sewerage system which may, in turn, cause disease in the persons who come into contact with the sewage.

Disease following the rainstorm

A total of five persons were notified with leptospirosis. Two were admitted to hospital and one died, EPI-NEWS 34b/11. Furthermore, a questionnaire including 257 persons with occupational exposure demonstrated that 22% had fallen ill. The most frequently presenting symptoms were diarrhoea, colds and headaches. The questionnaire also demonstrated that disease was associated with smoking (hand to mouth contact) and lack of hand washing.

Prevention

Future city planning should include solutions facilitating the diversion of rain water before it reaches the sewers. Furthermore, it is important that everyone who comes into contact with inundated water employs personal protection gear including gloves and boots. Physicians should be aware that patients who have come into contact with the inundated water may be at risk of contracting a number of diseases.

(L. Müller, O. Wojcik, Dept. of Epidemiology J. Holt, A. Kjerulf, CIHU)

1 February 2012