Between 1 January and 30 June 2006, 323 people in Turkey underwent investigation
for Crimean-Congo haemorrhagic fever (CCHF) virus infection [1]. Among these,
150 cases were laboratory confirmed using enzyme-linked immunosorbent assay
(ELISA) and real-time PCR tests. These laboratory-confirmed cases, including
11 fatal cases, were reported from 22 Turkish provinces. The six provinces
in Kelkit Valley, northeastern Turkey are the most affected (Tokat, Sivas,
Gümüshane, Amasya, Yozgat and Corum provinces, figure 1). Most
of the people investigated reported having been bitten by ticks.
No cases have been reported from popular tourist resorts on the Mediterranean
coast. In the past three years, the annual number of cases (and deaths)
was 150 (6) in 2003; 249 (13) in 2004, and 266 (13) in 2005. Compared with
previous years, the 150 confirmed cases in 2006 so far suggest increased
activity of the virus in the area, although detection, diagnosis and notification
may have improved.
Figure 1. Provinces most affected, Crimean-Congo haemorrhagic
fever, Turkey, as of 30 June 2006.
Control measures implemented in Turkey
Turkey’s Ministry of Health has implemented control measures, in collaboration
with the Ministries of the Environment and of Agriculture and Rural Affairs,
and enhanced CCHF surveillance has been established nationwide. Case management
guidelines, including a treatment protocol with ribavirin, have been distributed
to health care facilities throughout Turkey. Four reference hospitals with
isolation facilities have also been identified in Ankara, Erzurum, Sivas
and Samsun. People in the occupational categories most at risk have been
alerted and informed about personal protective measures. Public awareness
campaigns are ongoing, stressing personal protective measures to avoid tick
bites, and targeting the rural population through television, radio, posters
and leaflets, and the Turkish Ministry of Health has made information available
on its website [3].The World Health Organization Country Office in Turkey
and the WHO Regional Office for Europe are sharing information with the
Turkish Ministry of Health to closely monitor the evolution of the disease
activity
Crimean-Congo haemorrhagic fever
CCHF viral infections are endemic in many countries in Africa, eastern Europe
and Asia, and occur also in the Middle East. Previous outbreaks in Europe
have been reported in Turkey in 2001-2003 (83 cases), in Kosovo and in Albania
in 2001 (18 and 8 cases respectively). CCHF is a severe disease in humans,
with a high mortality rate of around 30%, with death occurring in the second
week of illness [4]. Following infection via tick bite, the incubation period
is usually one to three days, with a maximum of nine days. Haemorrhage is
typical of established viral haemorrhagic fevers, and represents a hazard
to healthcare workers if universal precautions are not strictly followed.
Early treatment with oral or intravenous ribavirin may shorten and ameliorate
the illness, so suspicion of the diagnosis can benefit both patient and
carers.
The CCHF virus belongs to (and is the most important human pathogen of)
the Nairovirus group of viruses which are transmitted mainly by ticks of
the Hyalomma genus. The animal reservoirs for the CCHF virus include hares,
birds, ticks, cattle, sheep and goats. Humans who become infected with CCHF
acquire the virus from direct contact with blood or other infected tissues
from livestock (or possibly another human), or they may become infected
from a tick bite. The majority of cases have occurred in those involved
with the livestock industry, such as agricultural workers, slaughterhouse
workers and veterinarians.
Advice to travellers to northeastern Turkey
The European Centre for Disease Prevention and Control advises travellers
to the affected area to take general preventive measures to minimise the
exposure to tick bites [2]:
|
Minimise exposure, wearing light-coloured clothing (this
makes it easier to see ticks) covering arms and legs; tuck trousers
into socks and keep sleeves rolled down. |
|
Use insect repellent on the exposed skin (eg, DEET 30%) and on clothes
(eg, permethrin); before using repellents, pregnant women and children
under the age of 12 years should consult a physician or pharmacist. |
|
Inspect the body after possible exposure, and remove ticks immediately
by steady, gentle traction, using forceps or tweezers. When removing
the tick, protect hands with gloves or tissue. Grasp the tick as close
to the skin as possible, and rotate the tick 1-2 times, pulling back
gently but firmly. Avoid leaving mouth parts in the skin. Wash the affected
area with water and soap, and disinfect with iodine. Observe the area
for a few days, and consult a doctor if a pustule, rash or other signs
develop at the site of the bite. |
People who have travelled to any endemic area and develop symptoms after
a tick bite should contact their physician.
Acknowledgements
Thanks to Dr Evelyn Depoortere, European Centre for Disease Prevention and
Control