Time to reverse second-dose decision
With vaccines becoming more plentiful, strategy to delay followup shot no longer valid
“If you don’t protect the staff, you may have beds but no staff. I understand the politics of vaccinating as many people as possible, but it doesn’t make sense to have hospital workers not fully protected.” — Dr. Thierry Mesana, CEO of Ottawa Heart Institute.
Since March 12, the OHI has had four outbreaks of COVID-19 involving 15 patients and 14 staff members; all had had at least one dose of vaccine. Dr. Mesana urged that all patient-facing health workers receive their second doses of vaccine without delay.
The Canadian Cardiovascular Society agrees. In an open letter, it stated, “We fear that our public health organizations and governments have underestimated the negative impact of incomplete vaccination on the health-care workforce, which has had a direct negative effect on the health of Canadians from both COVID and non-COVID-related illnesses.”
Globally, Canada has ranked as low as 64th in the immunization rate per capita. Due to the shortage, Ottawa and the provinces have asked physicians and nurses to support “off-label” use of vaccines when trying to protect our older and vulnerable patients and our professional colleagues. Initially, it might have been politically expedient to immunize two persons partially rather than one person fully.
Health Canada initially recommended the manufacturers’ instructions be followed, namely 1921 days between doses for PfizerBioNTech, 21-28 days for Moderna and 28 days to 12 weeks for AstraZeneca. However, because of the vaccine shortage, the National Advisory Committee on Immunization urged that the interval between the first and second dose be extended to four months. No other country endorses this. Conservative Health Critic Michelle Rempel Garner asked NACI chair Dr. Caroline Quach-Thanh, “Would you have made that recommendation if there had been more supply?” She replied, “Of course not.”
Dr. Mona Nemer stated, “I’m not aware of data showing there is efficacy beyond two months of the first dose.” She termed this a “population level experiment.”
The problem exists not only for front-line health workers, but for older persons. Dr. Marc Romney, professor at the University of British Columbia, found: “The antibody response was actively triggered in young, healthy people following a single dose of vaccine, while the response was clearly not as robust in older individuals This indicates that some older people — not only in long-term care but also in the community — may be incompletely protected after their initial dose.”
Very relevant is an article by the Canadian Medical Protective Association, the organization that defends MDs in cases of malpractice , entitled, “Risk management when using drugs or medical devices offlabel.” It defines this as “prescribing different dosages or frequencies, lengthening or shortening the duration of treatments, or using different routes of administration than indicated on the drug label.”
In order to minimize the risk of liability, the CMPA recommends one “consider if there is sufficient support from the medical literature for the off-label use of the medication or product.” This has not been demonstrated for a fourmonth interval between vaccine doses.
Consider an analogous situation: If an oncologist were to dramatically alter an accepted chemotherapy regimen and a patient suffered severe adverse effects, how would the CMPA defend him/her?
According to Toronto Public Health, 68 per cent of workplace COVID-19 outbreaks have occurred in offices, warehouses, construction sites, and food processing plants. Most of these workers lack paid sick benefits, and the federal Canada Recovery Sickness Benefit is an inadequate substitute. Inasmuch as the new federal budget did not improve the CRSB, Christine Elliott finally indicated that she was considering a provincial paid sick leave program.
Although vaccines alone cannot rapidly resolve the pandemic, Ontario is now targeting “hot zones” and will send mobile vaccination teams to workplaces and residences in high-risk areas. Toronto and Peel are temporarily closing workplaces that have outbreaks.
Ottawa and the provincial and territorial ministers of health should promptly reverse their decision to prolong the interval between first and second vaccine doses to four months, at least for health and other essential workers, pregnant women, older persons, patients with underlying chronic medical conditions, and those living in crowded, multi-generational homes.
Justin Trudeau has promised that two million Pfizer doses per week during May and 2.5 million per week during June will be delivered. If this is true, it should be feasible to target the “hot zones” and also eliminate the four-month delay between first and second doses for most high-risk persons.