The Centers for Disease Control and Prevention (CDC) recently issued a health advisory regarding a drift of influenza A (H3N2) viruses this flu season, which may possibly lead to a decrease in flu vaccine effectiveness. In light of this development, the CDC re-iterated the importance of neuraminidase inhibitor antivirals for the prevention and treatment of influenza, as adjunct to vaccination. By reducing viral shedding, antiviral agents may reduce infectivity and therefore slow the further transmission of influenza; if this occurs in widespread fashion, it has been suggested that community transmission of influenza could be reduced.
In a new study published in PLOS One, researchers aimed to assess the effectiveness of neuraminidase inhibitors for use in quick containment of influenza by combining data from pre- and post-exposure prophylaxis studies and comparing it to findings from previous systematic reviews and meta-analyses.
A total of nine randomized controlled trials and eight observational studies were used in this investigation. Following prophylaxis, neuraminidase inhibitors provided 67–89% protection for individuals. Compared to placebo, a significantly lower pooled odds of lab confirmed seasonal or influenza A(H1N1)pdm09 infection was seen with both oseltamivir and zanamivir usage, indicating that both these agents are effective as prophylaxis for individuals and households, regardless of whether the drugs were taken pre- or post-exposure. The same observation, however, could not made beyond the household setting since no studies were found which directly supported the use of neuraminidase inhibitors for prevention of population-wide, community transmission of influenza. The authors conclude that beyond the household setting, the evidence for use of neuraminidase inhibitors on community transmission in wider population settings is limited.