As COVID-19 pandemic precautions drop off, medical experts are worried about a resurgence of RSV, a respiratory disease that is known to particularly affect children younger than two years.
RSV, also known as Respiratory Syncytial Virus, is an infection that appears to be rising in Australia, and more recently in the United States.
The Canadian Medical Association Journal (CMAJ) said in a commentary this week that RSV could see a resurgence in Canada if new precautions are not taken.
The article was authored by Pascal M. Lavoie, Frederic Reicherz, Alfonso Solimano and Joanne M. Langley, a group of doctors and researchers affiliated with the Department of Pediatrics at the University of British Columbia and the BC Children's Hospital.
"It is crucial that we continue to monitor respiratory illnesses to inform RSV prevention programs and help protect vulnerable patients. This may involve administering RSV monoclonal antibody therapy in high-risk children off season, which is a major departure from standard practice," said the article.
The authors have said since the beginning of the pandemic, many countries have observed a near total disappearance of RSV and influenza cases. They provided figures from Canada's Centre for Immunization and Respiratory Infectious Diseases. From August 2020 to May 2021, there were 239 positive RSV cases reported in Canada. During a similar period the year before, from August 2019 to May 2020, there were 18,860 positive RSV cases in Canada.
The article also said that for many months, Canada has had such a low incidence of RSV infection, it may mean that pregnant women and infants have had lower exposure and therefore pediatric immunity levels may be low.
The article also said it was likely that during the pandemic, pregnant women were less likely to be exposed to RSV, and thus less likely to boost their RSV antibodies to levels usually seen in the winter.
"This raises a possibility that infants are less well protected than usual and could become sicker if they are infected this summer," said the article.
The article said the RSV season in Canada is usually late fall to early spring. The authors said a proactive approach is needed in Canada. RSV often presents itself as a serious form of bronchiolitis, said the article.
"In anticipation of a possible resurgence of RSV in Canada, we suggest the following approach. First, as pandemic-related physical distancing measures are relaxed, health care providers should continue to emphasize basic hygiene measures such as washing hands," said the article.
"We support ongoing efforts to keep vulnerable infants from coming into contact with people with respiratory illness. Other protective measures like breastfeeding when possible and avoiding exposure to second-hand smoke should be continued and emphasized. Second, confirmatory RSV testing should continue, following usual indications, to provide surveillance data. Third, pediatric ICUs should anticipate an increase in severe RSV cases, as reported in Australia. Respiratory syncytial virus programs should prepare to administer immunoprophylaxis off season, to the highest-risk infants, if cases increase to levels that normally trigger the fall season start."
The authors said that RSV numbers in Canada have not spiked in any way, there should still be an effort toward preparation.
"In Canada, RSV programs have not yet prospectively defined how many cases of RSV infection would constitute a resurgence, but it seems reasonable to consider that even a few cases should trigger communications with stakeholders, particularly considering that for months we have seen zero cases every week in many jurisdictions. Nonetheless, it is worth mentioning that whether the use of RSV monoclonal therapy off season is cost-effective in this context is unclear. We do not anticipate drug shortages, but new arrangements may need to be co-ordinated for shipments and storage of Palivizumab, in preparation for a resurgence of RSV, earlier than usual," said the article.
