[Infectious Diseases News Brief]

Influenza: Canada
Season to date (24 August-13 December 2003), Health Canada has received 25,680 reports of laboratory tests for influenza; 3,540 tests (13.8%) were positive, including 3,538 influenza A detections (99.9%) and 2 influenza B detections (0.1%). The National Microbiology Laboratory has antigenetically characterized 294 influenza viruses; 267 (91%) A/Fujian/411/02(H3N2)-like, 25 (8.5%) A/Panama/2007/99(H3N2)-like, 1 (0.3%) A/New Caledonia/20/99(H1N1)-like and 1 (0.3%) H1N2. There has been a total of 210 outbreaks, including long-term care facilities/retirement lodges (119), hospitals (13) and schools (78), with a sharp increase in week 50 due to 23 new outbreaks reported in Ontario. British Columbia has reported two deaths in children that may be associated with influenza; however, laboratory confirmation is still pending. Current data in Canada, the U.S. and globally indicate that the impact of A/Fujian is still within the expected range observed for previous severe flu seasons.
Source: FluWatch, 7 December to 13 December 2003 (Week 50), The Centre for Infectious Disease Prevention and Control, Health Canada.

Influenza: United States
Since 28 September, World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) laboratories have tested 32,854 specimens for influenza viruses; 9,464 (28.8%) were positive. Of these, 9,395 (99.3%) were influenza A viruses, and 69 (0.7%) were influenza B viruses. Of the 9,395 influenza A viruses, 2,113 (22.5%) have been subtyped; 2,112 (>99.9%) were influenza A (H3N2) viruses, and one (<0.1%) was an influenza A (H1) virus. All 50 states have reported laboratory-confirmed influenza this season. Of 269 influenza viruses characterized antigenically, 265 were influenza A (H3N2) viruses, two were influenza A (H1) viruses, and two were influenza B viruses. The hemagglutinin proteins of the influenza A (H1) viruses were similar antigenically to the hemagglutinin of the vaccine strain A/New Caledonia/20/99. Of the 265 influenza A (H3N2) isolates that have been characterized, 62 (23%) were similar antigenically to the vaccine strain A/Panama/2007/99 (H3N2), and 203 (77%) were similar to a drift variant, A/Fujian/411/2002 (H3N2). Both influenza B viruses characterized were similar antigenically to B/Sichuan/379/99.
Source: Morbidity and Mortality Weekly Report, Volume 52, Number 50, 19 December 2003.

Syphilis: San Francisco
During the summer of 1999, an outbreak of early syphilis among men who have sex with men (MSM) who met their sex partners on the Internet presaged a rapidly expanding syphilis epidemic in San Francisco. By 2002, San Francisco had the highest rates of primary and secondary syphilis of any metropolitan area in the United States. During 1998-2002, the number of early syphilis cases increased, from 41 cases in 1998 to 495 cases in 2002. Concomitant with the increase in early syphilis was an increase in the proportion of cases among MSM, from 22% in 1998 to 88% in 2002. To assess the association between early syphilis infection and use of the internet by MSM to meet sex partners, the San Francisco Department of Public Health (SFDPH) analyzed surveillance data and case reports. The results of that analysis suggest that public health officials might find the internet to be an important tool for 1) promoting disease awareness, prevention, and control and 2) accessing sex partners of syphilis patients to conduct appropriate partner notification, evaluation, and management. The findings underscore the need for public health officials to understand the role of the internet in facilitating the spread of sexually transmitted diseases (STDs), including the human immunodeficiency virus (HIV). With the assistance of community partners, other jurisdictions can examine the online social/sexual networks that are used commonly in their gay and bisexual communities and develop an effective means of communicating prevention and control messages online.
Source: Morbidity and Mortality Weekly Report, Volume 52, Number 50, 19 December 2003.

Please Note: There will be no issue the week of 2 January 2004.

The details given are for information only and may be very provisional. Where incidents are considered of national importance and are ongoing, the initial report will be updated as new information becomes available.

[Infectious Diseases News Brief]