Norovirus Surveillance: An Epidemiological Perspective.

Area of Science:

• Public Health
• Infectious Disease Epidemiology
• Gastroenterology

Background:

• Norovirus surveillance is challenging due to low healthcare seeking behavior among infected individuals.
• Gastrointestinal infection surveillance in England and Wales since 1992 highlighted the significant impact of norovirus outbreaks.
• Over 1800 norovirus hospital outbreaks affected more than 45,000 patients and staff in England during the initial surveillance period.

Purpose of the Study:

• To establish a dedicated surveillance system for norovirus outbreaks in hospitals.
• To collect timely and detailed information on norovirus outbreaks for public health response.
• To provide data for understanding norovirus epidemiology and informing potential interventions like vaccination.

Main Methods:

• Implementation of the Hospital Norovirus Outbreak Reporting Scheme (HNORS) starting January 2009.
• Infection control staff report outbreak details including symptom onset dates and necessary ward closures.
• Data collection focused on the initial three years of HNORS (2009-2011).

Main Results:

• HNORS reported 4,000 norovirus outbreaks between 2009 and 2011, impacting 40,000 patients and 10,000 staff.
• These outbreaks resulted in an average of 13,000 patient and 3,400 staff illnesses annually.
• An average of 15,000 hospital bed days were lost each year due to norovirus outbreaks.

Conclusions:

• The Hospital Norovirus Outbreak Reporting Scheme (HNORS) provides valuable data on the epidemiology of hospital-acquired norovirus.
• Integrated approaches combining laboratory testing and enhanced outbreak reporting are crucial for a comprehensive understanding of norovirus.
• Further research is essential, particularly with the potential development of a norovirus vaccine.