The majority of Pandemic H1N1 influenza cases might have been mild in the Middlesex-London area, but the local health unit considers this a learning experience – call it a test run – for a more severe pandemic outbreak.
Challenges faced during the Pandemic H1N1 influenza outbreak in the community have taught the Middlesex-London Health Unit many lessons in how to successfully organize mass immunization campaigns.
Bryna Warshawsky, Associate Medical Officer of Health for the health unit, presented a final summary on the Pandemic H1N1 Influenza at the Board of Health meeting Feb. 18. Warshawsky outlines the number of cases reported in the area, as well as the health unit’s response to raise public awareness and conduct its vaccination campaign.
Warshawsky says Pandemic H1N1 influenza was more widespread than the numbers indicate. The reported number of cases may be skewed because most people with symptoms did not seek medical attention and only a select few were tested, as recommended by the health unit.
“We really have no idea of the number of cases in our community,” she says. “There actually were a large number of people who got ill; we know that from looking at school absenteeism. At the peak of the disease there were a lot of people who were sick … Many people just managed at home and never needed to seek medical care.
“What this points out to us is how fast influenza can spread in the community and how many people can get sick in a short period of time.”
The first local resident with a laboratory-confirmed case of Pandemic H1N1 was reported on May 6 and his infection was reportedly acquired during travel to Mexico. By the end of summer, there were 23 laboratory-confirmed cases and 29 influenza A cases likely to be the Pandemic H1N1 strain. This was relatively mild compared to other areas of the province.
The second wave hit in early October and the numbers steadily decreased through December. In total, 224 laboratory-confirmed cases of Pandemic H1N1 influenza and 167 influenza A cases likely to be Pandemic H1N1 were reported among Middlesex-London residents. Of this number, 92 people were hospitalized and eight people died – most had underlying medical conditions.
From Oct. 26, when the vaccine became available, until Dec. 17 the health unit ran 111 large community clinics and several smaller clinics for selected populations. In January, five ‘catch-up’ clinics were held for those unable to receive the vaccine in the previous months.
A total of 105,287 Pandemic H1N1 influenza vaccinations were provided as of Jan. 29, as well as 21,274 seasonal influenza vaccinations. Both vaccines are still available at select locations in the Middlesex-London area.
One of the unique challenges of organizing a vaccination campaign of this size was the limited supply of the vaccine during the first few weeks it was available. Typically the health unit provides an influenza vaccine to whomever wants it, however the limited availability necessitated the implementation of eligibility criteria.
“We had to be sure the people we were vaccinating were the appropriate people according to the eligibility criteria that were established federally and provincially. That was hard because they were also a different group than you would normally expect to prioritize a vaccine to,” says Warshawsky.
Running a total of 116 community clinics required a large amount of staff and volunteers, and collaboration with community partners.
For the first time the health unit used Twitter to notify social media users about developments in its response to the outbreak, along with rapidly changing information, such as wait times at immunization clinics.
The health unit also published a weekly surveillance report from Sept. 11-Dec. 20, and resumed Jan. 11 until present to inform the public about the spread of the virus in the community. A dedicated H1N1 section on the website was created to post information.
The London Transit strike, which occurred during the immunization campaign, potentially limited access for some who rely on public transportation.
The total cost of the campaign as of Dec. 31 was more than $1.9 million, which will be reimbursed by the Ministry of Health and Long-Term Care.
“Overall I think it was a very successful campaign. It focused a lot on communication and we’ve been refining those all along, using the new mechanisms and tools and we were able to communicate frequently,” says Warshawsky.
“We were able to vaccinate a large number of people and we could have done that more rapidly if we’d had the vaccine available. We were limited by the vaccine supply.”
It is unlikely to have another wave of the illness this flu season because of the number of people vaccinated and the amount of people who have already contracted the virus and have built up immunity, she says. However, it is possible it will return next flu season.
A formal evaluation, including debriefing with the Incident Management Team, an online survey of staff and health unit volunteers is underway.
To view the complete report visit https://www.healthunit.com/articlesPDF/15645.pdf.