Influenza among U.K. Pilgrims to Hajj, 2003

1882 Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 10, No. 10, October 2004 been in contact with people with fever for several weeks before his illness. He lived in close proximity to goats and cattle, but no blood samples were taken from these animals. Although no ticks were found on nearby goats, 10 Amblyomma and Hyalomma ticks were collected from three cattle. Ticks were negative for CCHF virus isolation on suckling mice and RT-PCR amplification. No other case of fever accompanied by hemorrhage was reported in the area, and none of the patient’s 14 close contacts became ill. Of the four close contacts from whom blood samples were taken, analyses for IgM and IgG antibodies against CCHF virus were negative by ELISA. While no clinical case of CCHF has ever been reported in Senegal, studies dating from 1969 indicate that CCHF virus had been found in various locations in the country (2,3). In the village of Bandia, in the same district where the reported case was observed, a study conducted from 1986 to 1988 showed a prevalence of anti-CCHF IgG of 3.2% in the human population (4). Another study, conducted in the same area from 1989 to 1992, showed seroconversions for several ruminants and isolated the virus from ticks (5). During CCHF outbreaks, an average of 30% of people who had the disease died (case-fatality ratio). It is often discovered during nosocomial outbreaks, as was the case in Mauritania, a country on Sénégal’s northern border, in 2003 (P. Nabeth, unpub. data). To prevent outbreaks of CCHF, public awareness campaigns aimed at the populations most at risk—livestock farmers, butchers, and health personnel—must be conducted, and the epidemiologic alert systems must be strengthened. In addition, conditions that enhance maintenance of the virus in nature and its transmission to humans must be better understood so adequate control measures can be developed. Pierre Nabeth,* Moussa Thior,† Ousmane Faye,* and François Simon* *Institut Pasteur de Dakar, Dakar, Sénégal; and †Centre de santé, Popenguine, Sénégal