Influenza is a highly contagious acute respiratory disease, usually self-limited. Attacking the respiratory tract in humans it's caused by infection with influenza type A or B virus that occurs in outbreaks which are varying in severity almost every winter.
The aims of this study are: to identify the serotypes of influenza cases during Hajj season in Makkah, Jeddah and Almadina and to provide baseline information for understanding epidemiology of influenza in Hajj.
Methodology
A cross sectional study was conducted during Hajj period (17/12/2005--- 6/1/2006) within some hospitals and airports in Makkah, Jeddah and Almadinah cities. The case was defined as any patient who is suffering from fever of at least 38°C, in combination with either cough or sore throat and time of onset of fever within the last 72 hours, and age one year and above.
Trained staffs were involved for collection, storage, transportation of specimen (throat swab) and filling the required structured questionnaire. Cross tables were constructed to compare different risk factors.
Results
Suspected influenza cases.The mean age of the cases and standard deviation was 51.6± 13.3 years. 100% of cases were Hajjis. They were of 15 nationalities, mainly from Iran and Turkey (14.8%) for each. The clinical features which are reported by the suspected influenza cases were fever which was reported by all cases, then cough (72.3%) and at least one was blocked nose (16%). 29.9% were vaccinated, and 14.2% used antibiotics.
Confirmed influenza cases: 9.7% of suspected influenza cases were confirmed by lab to have influenza virus. The mean age of the cases and standard deviation was 40.0± 15.0years. The cases were of 9 nationalities, majority of them from Pakistan (28.3%). The clinical features were fever (100%), cough (66.0%), and the least was blocked nose. Only 14.9% of the cases were vaccinated against influenza, and 25.5% used antibiotics. Most of the confirmed influenza cases had influenza type A viruses (76.6%), and 23.4% had influenza type B viruses, and the most predominant serotype among the confirmed influenza isolates was A/H1N1 which accounts for (34.0%), followed by FLU A not typed which accounts for (29.8%)
Conclusion
nfluenza viruses are important pathogens especially during Hajj season, and the influenza serotypes which spread in Hajj season are the same as those which spread all over the world and those which are known by the World Health Organization (WHO), and Centers for Disease Control and Prevention (CDC) and these serotypes are included in the influenza vaccine for 2005-06 season. So influenza prevention can be applied by using the influenza vaccine especially to the high risk groups, and to those who are going to Hajj.