For the signatories of the study published in BMJ Global Health, health policies and the global interest resulting from the financial and social crises make eradication of the virus possible, but, according to specialists from the University of Otago Wellington (New Zealand), the main objectives are to ensure greater vaccination coverage, capable of responding quickly to variants. "Although our analysis is preliminary, with several subjective elements, it seems to place the eradication of Covid-19 within the realm of the possible, especially in terms of technical feasibility", say the authors of the study, which includes comparative data from technical, socio-political factors and economics of Covid-19, polio and smallpox infections.
The researchers used a three-point scoring system for each of 17 variables, including availability of a safe and effective vaccine, lifetime immunity, the impact of public health measures, and effective government management of infection control. Political and public concern with economic and social repercussions or the acceptance of restrictive measures were also calculated. Mean scores in the study totalled 2.7 for smallpox, 1.6 for Covid-19, and 1.5 for polio. Smallpox was declared eradicated in 1980 and two of the three poliovirus serotypes have also been eradicated globally.
Experts recognise that, in relation to smallpox and polio, the technical challenges of eradicating Covid-19 include low vaccine acceptance and the emergence of more transmissible variants. “However, viral evolution has its limits. It is to be expected that the virus will eventually reach its maximum capacity and that new vaccines will be designed”, they argue.
Persistence of the virus in animal reservoirs could also frustrate efforts, but it doesn't appear to be a serious problem, the researchers add. On the other hand, the “unprecedented global interest in disease control and massive investment in pandemic vaccination” is highlighted. Unlike smallpox and polio, Covid-19 benefits from the additional impact of public health measures such as border control, social distancing and the use of masks, which “can be very effective if [they are] well implemented”.
Covid-19 elimination has been achieved and sustained over long periods in several Asian regions, “providing proof that global eradication is technically possible,” they summarise. Among the future challenges, the study identifies achieving international cooperation to fight “vaccine nationalism”.